The calculation of value quot for highspeed register set to three
was wrong. This patch fixes the calculation so that the serial port
for baudrates bigger then 576000 baud is working correctly.
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Precedence of & and >> is not the same and is not left to right.
shift has higher precedence and should be done after the mask.
Add parentheses around the masks.
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no real value in displaying "Serial: IMX driver" in every boot.
The uart_register_driver() can fail and even so the "Serial: IMX driver" will
be displayed, which is not really helpful.
This is particularly annoying when booting multi_v7_defconfig kernel on a SoC
that is not a i.MX and even though this message gets displayed.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When kzalloc() fails the core MM will already complain about it, so there is
no need to have the error message locally.
Remove the unneeded error message.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Instead of jumping to 'error_out1' label we can simplify the code and return the
error code directly.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On a imx system with ttymxc0, ttymxc1 and ttymxc4 registered we see the
following output from 'cat /proc/interrupts':
$ cat /proc/interrupts
CPU0
...
58: 39 GIC 58 2020000.serial
67: 115 GIC 67 21f8000.i2c
The only uart irq that appears is ttymxc0, which is the console.
As ttymxc1 and ttymxc4 will only have their irq registered at imx_startup(),
they are not shown right after probe.
Transmitting to ttymxc1 and ttymxc4 will cause their irqs to be registered, but
the output shows:
$ echo "111111" > /dev/ttymxc1
$ echo "444444" > /dev/ttymxc4
$ cat /proc/interrupts
CPU0
...
58: 150 GIC 58 2020000.serial
59: 1 GIC 59
62: 1 GIC 62
67: 115 GIC 67 21f8000.i2c
,which misses printing the associated device address.
In order to fix this, register all the irqs inside the probe function via
devm_request_irq(), which will correctly report the serial interrupts associated
with their correspondent serial device and also helps simplyfing the code by
avoiding the calls to free_irq().
$ echo "111111" > /dev/ttymxc1
$ echo "444444" > /dev/ttymxc4
$ cat /proc/interrupts
CPU0
....
58: 202 GIC 58 2020000.serial
59: 1 GIC 59 21e8000.serial
62: 1 GIC 62 21f4000.serial
67: 115 GIC 67 21f8000.i2c
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For the case in which we just provide an address as an argument to the
earlycon console type like:
earlycon=msm_serial_dm,0xf991e000
We would report this as an IO port based mapping and not as MMIO. Simple
fix to use the port->iotype to decide which message to print.
Signed-off-by: Kumar Gala <galak@codeaurora.org>
Acked-by: Mark RUtland <mark.rutland@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We need the fixes in drivers/tty/tty_io.c that were done in there for
future patches in this branch.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit e676253b19 ("serial/8250: Add support for RS485 IOCTLs") added
references to TIOC[SG]RS48 on 8250_core.c. This change triggered the
need to define them in all the arches that uses tty/serial.
This made #ifdef TIOC[SG]RS48 obsolete.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit e676253b19 ("serial/8250: Add support for RS485 IOCTLs") added
references to TIOC[SG]RS48 on 8250_core.c. This change triggered the
need to define them in all the arches that uses tty/serial.
This made #ifdef TIOC[SG]RS48 obsolete.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The dma pointer under struct uart_8250_port is currently left
unassigned for non-ACPI platforms. It should be pointing to the dma
member in struct dw8250_data like how it was done for ACPI, so the core
8250 code will try to request for DMA when registering the port
If DMA is not enabled in device tree, request DMA will fail and the
driver will fall back to PIO
Signed-off-by: Ray Jui <rjui@broadcom.com>
Reviewed-by: JD (Jiandong) Zheng <jdzheng@broadcom.com>
Reviewed-by: Scott Branden <sbranden@broadcom.com>
Tested-by: Scott Branden <sbranden@broadcom.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch allows to read the REV_ID register in SPI mode and consequently
to properly detect the max3109. Indeed in SPI mode, this register is only
accessible by using indirect addressing.
Signed-off-by: Gregory Hermant <gregory.hermant@calao-systems.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 32726d2d55 ("ARM: SAMSUNG: Remove legacy clock code") removed
the Kconfig symbol SAMSUNG_CLOCK. Remove the last checks for its macro,
and the dead code they hide, too.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use container_of instead of casting first structure member.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds the required pieces to 8250-OMAP UART driver for DMA
support. The TX burst size is set to 1 so we can send an arbitrary
amount of bytes.
The RX burst is currently set to 48 which means we receive an DMA
interrupt every 48 bytes and have to reprogram everything. Less bytes in
the RX-FIFO mean that no DMA transfer will happen and the UART will send a
RX-timeout _or_ RDI event at which point the FIFO will be manually purged.
There is a workaround for TX-DMA on AM33xx where we put the first byte
into the FIFO to kick start the DMA process. Haven't seen this problem on
OMAP36xx (beagle board xm) or DRA7xx.
On AM375x there is "Usage Note 2.7: UART: Cannot Acknowledge Idle
Requests in Smartidle Mode When Configured for DMA Operations" in the
errata document. This problem persists even after disabling DMA in the
UART and will be addressed in the HWMOD.
v10:
- delay update_registers() from set_termios() until TX-DMA is
done. It has been reported / proved that invoking
update_registers() while TX-DMA is in progress may stall the
DMA operation and it won't finish.
- use the new omap DMA-TX-RX hooks and DMA only interrupt
routine.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We have (or will have) custom DMA callbacks in the omap driver due to
the different behaviour in the RX and TX case. To make this work
we need a few changes in the IRQ handler to invoke the rx_handler again
after the "manual" mode or retry the tx_handler again before falling
back to the manual mode.
Heikki didn't want to see the extra hacks in the generic / default irq
handler and Peter wasn't too happy about an OMAP-only IRQ handler. The
way I planned it is to use this extra IRQ routine only in DMA case. If
Peter dislike this approach then I hope Heikki doesn't block changes in
the default IRQ handler :)
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The omap needs a DMA request pending right away. If it is
enqueued once the bytes are in the FIFO then nothing will happen
and the FIFO will be later purged via RX-timeout interrupt.
This patch enqueues RX-DMA request on completion but not if it
was aborted on error. The first enqueue will happen in the driver
in startup.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch provides mostly a copy of serial8250_tx_dma() +
__dma_tx_complete() with the following extensions:
- DMA bug
At least on AM335x the following problem exists: Even if the TX FIFO is
empty and a TX transfer is programmed (and started) the UART does not
trigger the DMA transfer.
After $TRESHOLD number of bytes have been written to the FIFO manually the
UART reevaluates the whole situation and decides that now there is enough
room in the FIFO and so the transfer begins.
This problem has not been seen on DRA7 or beagle board xm (OMAP3). I am not
sure if this is UART-IP core specific or DMA engine.
The workaround is to use a threshold of one byte, program the DMA
transfer minus one byte and then to put the first byte into the FIFO to
kick start the transfer.
- support for runtime PM
RPM is enabled on start_tx(). We can't disable RPM on DMA complete callback
because there is still data in the FIFO which is being sent. We have to wait
until the FIFO is empty before we disable it.
For this to happen we fake a TX sent error and enable THRI. Once the
FIFO is empty we receive an interrupt and since the TTY-buffer is still
empty we "put RPM" via __stop_tx(). Should it been filed then in the
start_tx() path we should program the DMA transfer and remove the error
flag and the THRI bit.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The OMAP has a few corner cases where it needs a share of kindness of
affection to do the right thing. Heikki Krogerus suggested that instead
adding the quirks into the default DMA implementation, OMAP could get
its own copy of the function. And Alan suggested the same thing so here
we go.
This patch provides callbacks for custom TX/RX DMA implementation. If
there are not setup / used, then the default (current) implementation is
used.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After dmaengine_terminate_all() has been invoked then both DMA drivers
(edma and omap-dma) do not invoke dma_cookie_complete() to mark the
transfer as complete. This dma_cookie_complete() is performed by the
Synopsys DesignWare driver which is probably the only one that is used
by omap8250-dma and hence don't see following problem…
…which is that once a RX transfer has been terminated then following
query of channel status reports DMA_IN_PROGRESS (again: the actual
transfer has been canceled, there is nothing going on anymore).
This means that serial8250_rx_dma() never enqueues another DMA transfer
because it (wrongly) assumes that there is a transer already pending.
Vinod Koul refuses to accept a patch which adds this
dma_cookie_complete() to both drivers and so dmaengine_tx_status() would
report DMA_COMPLETE instead (and behave like the Synopsys DesignWare
driver already does). He argues that I am not allowed to use the cookie
to query the status and that the driver already cleaned everything up after
the invokation of dmaengine_terminate_all().
To end this I add a bookkeeping whether or not a RX-transfer has been
started to the 8250-dma code. It has already been done for the TX side.
*Now* we learn about the RX status based on our bookkeeping and don't
need dmaengine_tx_status() for this anymore.
Cc: vinod.koul@intel.com
Reviewed-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Right now it is possible that serial8250_tx_dma() fails and returns
-EBUSY. The caller (serial8250_start_tx()) will then enable
UART_IER_THRI which will generate an interrupt once the TX FIFO is
empty.
In serial8250_handle_irq() nothing will happen because up->dma is set
and so serial8250_tx_chars() won't be invoked. We end up with plenty of
interrupts and some "too much work for irq" output.
This patch introduces dma_tx_err in struct uart_8250_port to signal that
the last invocation of serial8250_tx_dma() failed so we can fill the TX
FIFO manually. Should the next invocation of serial8250_start_tx()
succeed then the dma_tx_err flag along with the THRI bit is removed and
DMA only usage may continue.
Reviewed-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch provides a 8250-core based UART driver for the internal OMAP
UART. The long term goal is to provide the same functionality as the
current OMAP uart driver and DMA support.
I tried to merge omap-serial code together with the 8250-core code.
There should should be hardly a noticable difference. The trigger levels
are different compared to omap-serial:
- omap serial
TX: Interrupt comes after TX FIFO has room for 16 bytes.
TX of 4096 bytes in one go results in 256 interrupts
RX: Interrupt comes after there is on byte in the FIFO.
RX of 4096 bytes results in 4096 interrupts.
- this driver
TX: Interrupt comes once the TX FIFO is empty.
TX of 4096 bytes results in 65 interrupts. That means there will
be gaps on the line while the driver reloads the FIFO.
RX: Interrupt comes once there are 48 bytes in the FIFO or less over
"longer" time frame. We have
1 / 11520 * 10^3 * 16 => 1.38… ms
1.38ms to react and purge the FIFO on 115200,8N1. Since the other
driver fired after each byte it had ~5.47ms time to react. This
_may_ cause problems if one relies on no missing bytes and has no
flow control. On the other hand we get only 85 interrupts for the
same amount of data.
It has been only tested as console UART on am335x-evm, dra7-evm and
beagle bone. I also did some longer raw-transfers to meassure the load.
The device name is ttyS based instead of ttyO. If a ttyO based node name
is required please ask udev for it. If both driver are activated (this
and omap-serial) then this serial driver will take control over the
device due to the link order
v9…v10:
- Tony noticed that omap3 won't show anything after waking up
from core off. In v9 I reworked the register restore and set
IER to 0 by accident. This went unnoticed because start_tx
usually sets ier (either due to DMA bug or due to TX-complete
IRQ).
- dropped EFR and SLEEP from capabilities. We do have both but
nobody should touch it. We already handle SLEEP ourself.
- make the private copy of the registers (like EFR) u8 instead
u32
- drop MDR1 & DL[ML] reset in restore registers. Does not look
required it is set to the required value later.
- update MDR1 & SCR only if changed.
- set MDR1 as the last thing. The errata says that we should
setup everything before MDR1 set.
- avoid div by 0 in omap_8250_get_divisor() if baud rate gets
very large (Frans Klaver fixed the same thing omap-serial)
- drop "is in early stage" from Kconfig.
v8…v9:
- less on a file seems to hang the am335x after a while. I
believe I introduce this bug a while ago since I can reproduce
this prior to v8. Fixed by redoing the omap8250_restore_regs()
v7…v8:
- redo the register write. There is now one function for that
which is used from set_termios() and runtime-resume.
- drop PORT_OMAP_16750 and move the setup to the omap file. We
have our own set termios function anyway (Heikki Krogerus)
- use MEM instead of MEM32. TRM of AM/DM37x says that 32bit
access on THR might result in data abort. We only need 32bit
access in the errata function which is before we use 8250's
read function so it doesn't matter.
v4…v7:
- change trigger levels after some tests with raw transfers.
v3…v4:
- drop RS485 support
- wire up ->throttle / ->unthrottle
v2…v3:
- wire up startup & shutdown for wakeup-irq handling.
- RS485 handling (well the core does).
v1…v2:
- added runtime PM. Could somebody could please double check
this?
- added omap_8250_set_termios()
Reviewed-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Frans Klaver <frans.klaver@xsens.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
if I boot with console=ttyS0 and the omap driver is module I end up with
| console [ttyS0] disabled
| omap8250 44e09000.serial: ttyS0 at MMIO 0x44e09000 (irq = 88, base_baud = 3000000) is a 8250
| Unable to handle kernel paging request at virtual address c07a9de0
| Modules linked in: 8250_omap(+)
| CPU: 0 PID: 908 Comm: modprobe Not tainted 3.17.0-rc5+ #1593
| PC is at serial8250_console_setup+0x0/0xc8
| LR is at register_console+0x13c/0x3a4
| [<c0078788>] (register_console) from [<c02d0340>] (uart_add_one_port+0x3cc/0x420)
| [<c02d0340>] (uart_add_one_port) from [<c02d38a4>] (serial8250_register_8250_port+0x298/0x39c)
| [<c02d38a4>] (serial8250_register_8250_port) from [<bf006274>] (omap8250_probe+0x218/0x3dc [8250_omap])
| [<bf006274>] (omap8250_probe [8250_omap]) from [<c02e3424>] (platform_drv_probe+0x2c/0x5c)
| [<c02e3424>] (platform_drv_probe) from [<c02e1eac>] (driver_probe_device+0x104/0x228)
…
| [<c009fa48>] (SyS_init_module) from [<c000e6e0>] (ret_fast_syscall+0x0/0x30)
| Code: 7823603b f8314620 051b3013 491ed416 (44792204)
because serial8250_console_setup() is already gone.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Frans reworded the two comments with better English for better
understanding. His review hit the mailing list after the patch got
applied so here is an incremental update.
Reported-by: Frans Klaver <frans.klaver@xsens.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When using mxs-auart based console, sometime we need the sysrq function
to help debugging kernel. The sysrq code is basically there,
this patch just simply enable it.
Signed-off-by: Janusz Uzycki <j.uzycki@elproma.com.pl>
Reviewed-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This error message is not necessary. The driver core code will print all
probe error messages. It also resolves some error codes to proper error
messages. For example -EPROBE_DEFER will only be printed as an info message.
This patch removes the error message as the core prints the same
information.
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A port count mismatch occurs if mutex_lock_interruptible()
exits uart_open() and the port has already been opened. This may
prematurely close a port on an open tty. Since uart_close() is _always_
called if uart_open() fails, the port count must be corrected if errors
occur.
Always increment the port count in uart_open(), regardless of errors;
always decrement the port count in uart_close(). Note that
tty_port_close_start() decrements the port count when uart_open()
was successful.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uart_start() only claims the port->lock to call __uart_start(),
which does the actual processing. Eliminate the extra acquire/release
in uart_write(); call __uart_start() directly with port->lock already
held.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The key function of uart_add_one_port() is to cross-reference the
UART driver's port structure with the serial core's state table;
keep the assignments together and document this crucial association.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty_port_init() initializes close_delay and closing_wait to these
same values; remove.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The wrapped line looks wrong and out-of-place; leave it as
>80 char line.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The low-level uart driver may modify termios settings to override
settings that are not compatible with the uart, such as CRTSCTS.
Thus, callers of the low-level uart driver's set_termios() method must
hold termios_rwsem write lock to prevent concurrent access to termios,
in case such override occurs.
The termios_rwsem lock requirement does not extend to console setup
(ie., uart_set_options), as console setup cannot race with tty
operations. Nor does this lock requirement extend to functions which
cannot be concurrent with tty ioctls (ie., uart_port_startup() and
uart_resume_port()).
Further, always claim the port mutex to protect hardware
re-reprogramming in the set_termios() uart driver method. Note this
is unnecessary for console initialization in uart_set_options()
which cannot be concurrent with other uart operations.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty buffers (and any line discipline buffers) must be flushed after
the UART hardware has shutdown; otherwise, a racing open on the same
tty may receive data from the previous session, which is a security
hazard. However, holding the port mutex while flushing the line
discipline buffers creates a lock inversion if the set_termios()
handler takes the port mutex (as it does in the followup patch,
'serial: Fix locking for uart driver set_termios method'.
Flush the ldisc buffers after dropping the port mutex; the tty lock
is still held which prevents a concurrent open() from advancing while
flushing. Since no new rx data is possible after uart_shutdown() until
a new open reinitializes the port, the later flush has no impact on
what data is being discarded.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the context of the final tty & port close, flushing the tx
ring buffer after the hardware has already been shutdown and
the ring buffer freed is neither required nor desirable.
uart_flush_buffer() performs 3 operations:
1. Resets tx ring buffer indices, but the tx ring buffer has
already been freed and the indices are reset if the port is
re-opened.
2. Calls uart driver's flush_buffer() method
5 in-tree uart drivers define flush_buffer() methods:
amba-pl011, atmel-serial, imx, serial-tegra, timbuart
These have been refactored into the shutdown() method, if
required.
3. Kicks the ldisc for more writing, but this is undesirable.
The file handle is being released; any waiting writer will
will be kicked out by tty_release() with a warning. Further,
the N_TTY ldisc may generate SIGIO for a file handle which
is no longer valid.
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty_ldisc_flush() first clears the line discipline input buffer,
then clears the tty flip buffers. However, this allows for existing
data in the tty flip buffers to be added after the ldisc input
buffer has been cleared, but before the flip buffers have been cleared.
Add an optional ldisc parameter to tty_buffer_flush() to allow
tty_ldisc_flush() to pass the ldisc to clear.
NB: Initially, the plan was to do this automatically in
tty_buffer_flush(). However, an audit of the behavior of existing
line disciplines showed that performing a ldisc buffer flush on
ioctl(TCFLSH) was not always the outcome. For example, some line
disciplines have flush_buffer() methods but not ioctl() methods,
so a ->flush_buffer() command would be unexpected.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When changing the ldisc on one end of a pty pair, there may be
waiting readers/writers on the other end which may not exit from
the ldisc i/o loop, preventing tty_ldisc_lock_pair_timeout() from
acquiring the other side's ldisc lock.
Only acquire this side's ldisc lock; although this will no longer
prevent the other side from writing new input, that input will not
be processed until after the ldisc change completes. This has no
effect on normal ttys; new input from the driver was never disabled.
Remove tty_ldisc_enable_pair().
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When hanging up one end of a pty pair, there may be waiting
readers/writers on the other end which may not exit, preventing
tty_ldisc_lock_pair() from acquiring the other side's ldisc lock.
Only acquire this side's ldisc lock; although this will no longer
prevent the other side from writing new input, that input will not
be processing until after the ldisc hangup is complete.
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty_ldisc_lock(), tty_ldisc_unlock(), and tty_ldisc_lock_nested()
are low-level aliases for the underlying lock mechanism. Rename
with double underscore to allow for new, higher level functions
with those names.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When releasing one end of a pty pair, that end may just have written
to the other, which the input processing worker, flush_to_ldisc(), is
still working on but has not completed the copy to the other end's
read buffer. So input may not appear to be available to a waiting
reader but yet TTY_OTHER_CLOSED is now observed. The n_tty line
discipline has worked around this by waiting for input processing
to complete and then re-checking if input is available before
exiting with -EIO.
Since the tty/ldisc lock reordering, the wait for input processing
to complete can now occur during final close before setting
TTY_OTHER_CLOSED. In this way, a waiting reader is guaranteed to
see input available (if any) before observing TTY_OTHER_CLOSED.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With the revised tty lock order and lockdep annotation, claiming
the pty slave lock is now safe while still holding the pty master lock.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Eliminate the requirement of specifying the tty lock nesting at
lock time; instead, set the lock subclass for slave ptys at pty
install (normal ttys and master ptys use subclass 0).
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When releasing the master pty, the slave pty also needs to be locked
to prevent concurrent tty count changes for the slave pty and to
ensure that only one parallel master and slave release observe the
final close, and proceed to destruct the pty pair. Conversely, when
releasing the slave pty, locking the master pty is not necessary
(since the master's state can be inferred by the slave tty count).
Introduce tty_lock_slave()/tty_unlock_slave() which acquires/releases
the tty lock of the slave pty. Remove tty_lock_pair()/tty_unlock_pair().
Dropping the tty_lock is no longer required to re-establish a stable
lock order.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The local o_tty variable in tty_release() is now accessed only
when closing the pty master.
Set o_tty to slave pty when closing pty master, otherwise NULL;
use o_tty != NULL as replacement for pty_master.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Passing the 'other' tty to tty_release_checks() only makes sense
for a pty pair; make o_tty scope local instead.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Passing the 'other' tty to tty_ldisc_release() only makes sense
for a pty pair; make o_tty function local instead.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Perform work flush for both ends of a pty pair within tty_flush_works(),
rather than calling twice.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the slave side closes and its tty count is 0, the pty
pair can be destroyed; the master side must have already
closed for the slave side tty count to be 0. Thus, only the
pty master close must check if the slave side has closed by
checking the slave tty count.
Remove the pre-computed closing flags and check the actual count(s).
Regular ttys are unaffected by this change.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Holding the tty_lock() is necessary to prevent concurrent changes
to the tty count that may cause it to differ from the open file
list count. The tty_lock() is already held at all call sites.
NB: Note that the check for the pty master tty count is safe because
the slave's tty_lock() is held while decrementing the pty master
tty count.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Releasing the tty locks while waiting for the tty wait queues to
be empty is no longer necessary nor desirable. Prior to
"tty: Don't take tty_mutex for tty count changes", dropping the
tty locks was necessary to reestablish the correct lock order between
tty_mutex and the tty locks. Dropping the global tty_mutex was necessary;
otherwise new ttys could not have been opened while waiting.
However, without needing the global tty_mutex held, the tty locks for
the releasing tty can now be held through the sleep. The sanity check
is for abnormal conditions caused by kernel bugs, not for recoverable
errors caused by misbehaving userspace; dropping the tty locks only
allows the tty state to get more sideways.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Holding tty_mutex is no longer required to serialize changes to
the tty_count or to prevent concurrent opens of closing ttys;
tty_lock() is sufficient.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that re-open is not permitted for a legacy BSD pty master,
using TTY_CLOSING to indicate when a tty can be torn-down is
no longer necessary.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Holding tty_mutex for a tty re-open is no longer necessary since
"tty: Clarify re-open behavior of master ptys". Because the
slave tty count is no longer accessed by tty_reopen(), holding
tty_mutex to prevent concurrent final tty_release() of the slave
pty is not required.
As with "tty: Re-open /dev/tty without tty_mutex", holding a
tty kref until the tty_lock is acquired is sufficient to ensure
the tty has not been freed, which, in turn, is sufficient to
ensure the tty_lock can be safely acquired and the tty count
can be safely retrieved. A non-zero tty count with the tty lock
held guarantees that release_tty() has not run and cannot
run concurrently with tty_reopen().
Change tty_driver_lookup_tty() to acquire the tty kref, which
allows the tty_mutex to be dropped before acquiring the tty lock.
Dropping the tty_mutex before attempting the tty_lock allows
other ttys to be opened and released, without needing this
tty_reopen() to complete.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Opening /dev/tty (ie., the controlling tty for the current task)
is always a re-open of the underlying tty. Because holding the
tty_lock is sufficient for safely re-opening a tty, and because
having a tty kref is sufficient for safely acquiring the tty_lock [1],
tty_open_current_tty() does not require holding tty_mutex.
Repurpose tty_open_current_tty() to perform the re-open itself and
refactor tty_open().
[1] Analysis of safely re-opening the current tty w/o tty_mutex
get_current_tty() gets a tty kref from the already kref'ed tty value of
current->signal->tty while holding the sighand lock for the current
task. This guarantees that the tty pointer returned from
get_current_tty() points to a tty which remains referenceable
while holding the kref.
Although release_tty() may run concurrently, and thus the driver
reference may be removed, release_one_tty() cannot have run, and
won't while holding the tty kref.
This, in turn, guarantees the tty_lock() can safely be acquired
(since tty->magic and tty->legacy_mutex are still a valid dereferences).
The tty_lock() also gets a tty kref to prevent the tty_unlock() from
dereferencing a released tty. Thus, the kref returned from
get_current_tty() can be released.
Lastly, the first operation of tty_reopen() is to check the tty count.
If non-zero, this ensures release_tty() is not running concurrently,
and the driver references have not been removed.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Opening the slave BSD pty first already returns -EIO from the slave
pty_open(), which in turn causes the newly installed tty pair to be
released before returning from tty_open(). However, this can also
cause a parallel master BSD pty open to fail because the pty pair
destruction may already been taking place in tty_release().
Failing at driver->install() if the slave pty is opened first ensures
that a pty master open cannot fail, because the driver tables will
not have been updated so tty_driver_lookup_tty() won't find the
master pty (and attempt to "re-open" it).
In turn, this guarantees that any tty with a tty->count == 0 is
in final close (rather than never opened).
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Although perhaps not obvious, the TTY_CLOSING bit is set when the
tty count has been decremented to 0 (which occurs while holding
tty_lock). The only other case when tty count is 0 during a re-open
is when a legacy BSD pty master has been opened in parallel but
after the pty slave, which is unsupported and returns an error.
Thus !tty->count contains the complete set of degenerate conditions
under which a tty open fails.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Re-opening master ptys is not allowed. Once opened and for the remaining
lifetime of the master pty, its tty count is 1. If its tty count has
dropped to 0, then the master pty was closed and TTY_CLOSING was set,
and destruction may begin imminently.
Besides the normal case of a legacy BSD pty master being re-opened
(which always returns -EIO), this code is only reachable in 2 degenerate
cases:
1. The pty master is the controlling terminal (this is possible through
the TIOCSCTTY ioctl). pty masters are not designed to be controlling
terminals and it's an oversight that tiocsctty() ever let that happen.
The attempted open of /dev/tty will always fail. No known program does
this.
2. The legacy BSD pty slave was opened first. The slave open will fail
in pty_open() and tty_release() will commence. But before tty_release()
claims the tty_mutex, there is a very small window where a parallel
master open might succeed. In a test of racing legacy BSD slave and
master parallel opens, where:
slave open attempts: 10000 success:4527 failure:5473
master open attempts: 11728 success:5789 failure:5939
only 8 master open attempts would have succeeded reaching this code and
successfully opened the master pty. This case is not possible with
SysV ptys.
Always return -EIO if a master pty is re-opened or the slave is opened
first and the master opened in parallel (for legacy BSD ptys).
Furthermore, now that changing the slave's count is not required,
the tty_lock is sufficient for preventing concurrent changes to the
tty being re-opened (or failing re-opening).
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that tty_ldisc_hangup() does not drop the tty lock, it is no
longer possible to observe TTY_HUPPING while holding the tty lock
on another cpu.
Remove TTY_HUPPING bit definition.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Dropping the tty lock to acquire the tty->ldisc_sem allows several
race conditions (such as hangup while changing the ldisc) which requires
extra states and testing. The ldisc_sem->tty_lock lock order has
not been required since tty buffer ownership was moved to tty_port.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty->ldisc_sem write lock is sufficient for serializing changes
to tty->ldisc; holding the tty lock is not required.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Added recognition of EndRun Technologies PCIe PTP slave card
and setup two ttySx ports for communication with the card for
retrieval of PTP based time and to communicate with the card's
Linux OS.
Signed-off-by: Mike Skoog <mskoog@endruntechnologies.com>
Signed-off-by: Mike Korreng <mkorreng@endruntechnologies.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The stale comment refers to lock behavior which was eliminated in
commit 6d76bd2618,
n_tty: Make N_TTY ldisc receive path lockless.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Packet mode can only be set for a pty master, and a pty master is
always in raw mode since its termios cannot be changed.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The pty master read() can miss the wake up for a packet mode
status change. For example,
CPU 0 | CPU 1
n_tty_read() | n_tty_packet_mode_flush()
... | .
if (packet & link->ctrl_status) { | .
/* no new ctrl_status ATM */ | .
| spin_lock
| ctrl_status |= TIOCPKT_FLUSHREAD
| spin_unlock
| wake_up(link->read_wait)
} |
set_current_state(TASK_INTERRUPTIBLE) |
... |
The pty master read() will now sleep (assuming there is no input) having
missed the read_wait wakeup.
Set the task state before the condition test.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Updates to the packet mode enable require holding the ctrl_lock;
the serialization prevents corruption of adjacent fields.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Because pty_set_pktmode() does not claim the slave's ctrl_lock
to clear ->ctrl_status (to avoid unnecessary lock nesting),
pty_set_pktmode() may accidentally erase new ->ctrl_status updates.
For example,
CPU 0 | CPU 1
pty_set_pktmode() | pty_start()
spin_lock(master's ctrl_lock) |
tty->packet = 1 |
| if (tty->link->packet)
| spin_lock(slave's ctrl_lock)
| tty->ctrl_status = TIOCPKT_START
tty->link->ctrl_status = 0 |
Ensure the clear of ->ctrl_status occurs before packet mode is set
(and observable on another cpu).
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The slave's ctrl_lock serializes updates to the ctrl_status field
only, whereas the master's ctrl_lock serializes updates to the
packet mode enable (ie., the master does not have ctrl_status and
the slave does not have packet mode). Thus, claiming the slave's
ctrl_lock to access ->packet is useless.
Unlocked reads of ->packet are already smp-safe.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Interrupts are enabled in the n_tty_read() loop, ioctl(TIOCPKT)
and pty driver flush_buffer() routine; no need to save and restore
local interrupt state.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty driver's set_termios() method is called with interrupts
enabled; there is no need to save and restore the local interrupt state.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Packet mode is unique to the pty driver; move the packet mode state
change code from the generic tty ioctl handler to the pty driver.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The pty master's termios should never be set; currently, all code
paths which call the driver's set_termios() method ensure that the
pty slave's termios is being set.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The session and foreground process group pid references will be
non-NULL if tiocsctty() is stealing the controlling tty from another
session (ie., arg == 1 in tiocsctty()).
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Setting the controlling terminal for a session occurs with either
the first open of a non-pty master tty or with ioctl(TIOCSCTTY).
Since only the session leader can set the controlling terminal for
a session (and the session leader cannot change), it is not
necessary to prevent a process from attempting to set different
ttys as the controlling terminal concurrently.
So it's only necessary to prevent the same tty from becoming the
controlling terminal for different session leaders. The tty_lock()
is sufficient to prevent concurrent proc_set_tty() for the same
tty.
Remove the tty_mutex lock region; add tty_lock() to tiocsctty().
While this may appear to allow a race condition between opening
the controlling tty via tty_open_current_tty() and stealing the
controlling tty via ioctl(TIOCSCTTY, 1), that race condition already
existed. Even if the tty_mutex prevented stealing the controlling tty
while tty_open_current_tty() returned the original controlling tty,
it cannot prevent stealing the controlling tty before tty_open() returns.
Thus, tty_open() could already return a no-longer-controlling tty when
opening /dev/tty.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tiocspgrp() is the lone caller of session_of_pgrp(); relocate and
limit to file scope.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Claim a read lock on the tasklist_lock while setting the controlling
terminal for the session leader. This fixes multiple races:
1. task_pgrp() and task_session() cannot be safely dereferenced, such
as passing to get_pid(), without holding either rcu_read_lock() or
tasklist_lock
2. setsid() unwisely allows any thread in the thread group to
make the thread group leader the session leader; this makes the
unlocked reads of ->signal->leader and signal->tty potentially
unordered, stale or even have spurious values.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty parameter to __proc_set_tty() cannot be NULL; all
call sites have already dereferenced tty.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Only the current task itself can set its controlling tty (other
than before the task has been forked). Equivalent to existing usage.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move the controlling tty-related functions and remove forward
declarations for __proc_set_tty() and proc_set_tty().
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty_pair_get_pty() has no in-tree users and tty_pair_get_tty()
has only one file-local user. Remove the external declarations,
the export declarations, and declare tty_pair_get_tty() static.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In ST16650V2 based serial uarts, while initalizing the PM state,
LCR registers are being initialized to 0 in serial8250_set_sleep().
If console port is already initialized and being used, this will
throws garbage in the console.
Signed-off-by: Sudhir Sreedharan <ssreedharan@mvista.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes commit 2dea53bf57,
"serial: of-serial: add PM suspend/resume support", which disables
the uart clock on suspend, but also causes a hardware hang on register
access if no_console_suspend command line option is used.
Also, not every of_serial device is an 8250 port, so the serial8250
suspend/resume functions should only be applied to a real 8250 port.
Signed-off-by: Jingchang Lu <jingchang.lu@freescale.com>
Tested-by: Joseph Lo <josephl@nvidia.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sparse lock annotations cannot represent conditional acquire, such
as mutex_lock_interruptible() or mutex_trylock(), and produce sparse
warnings at _every_ correct call site.
Remove lock annotations from tty_write_lock() and tty_write_unlock().
Fixes sparse warnings:
drivers/tty/tty_io.c:1083:13: warning: context imbalance in 'tty_write_unlock' - wrong count at exit
drivers/tty/tty_io.c:1090:12: warning: context imbalance in 'tty_write_lock' - wrong count at exit
drivers/tty/tty_io.c:1211:17: warning: context imbalance in 'tty_write_message' - unexpected unlock
drivers/tty/tty_io.c:1233:16: warning: context imbalance in 'tty_write' - different lock contexts for basic block
drivers/tty/tty_io.c:1285:5: warning: context imbalance in 'tty_send_xchar' - different lock contexts for basic block
drivers/tty/tty_io.c:2653:12: warning: context imbalance in 'send_break' - different lock contexts for basic block
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The struct uart_port.flags field is type upf_t, as are the matching
bit definitions. Change local mask variable to type upf_t.
Fixes sparse warnings:
drivers/tty/serial/serial_core.c:620:22: warning: invalid assignment: |=
drivers/tty/serial/serial_core.c:620:22: left side has type unsigned int
drivers/tty/serial/serial_core.c:620:22: right side has type restricted upf_t
drivers/tty/serial/serial_core.c:622:22: warning: invalid assignment: |=
drivers/tty/serial/serial_core.c:622:22: left side has type unsigned int
drivers/tty/serial/serial_core.c:622:22: right side has type restricted upf_t
drivers/tty/serial/serial_core.c:624:17: warning: restricted upf_t degrades to integer
drivers/tty/serial/serial_core.c:626:22: warning: invalid assignment: &=
drivers/tty/serial/serial_core.c:626:22: left side has type unsigned int
drivers/tty/serial/serial_core.c:626:22: right side has type restricted upf_t
drivers/tty/serial/serial_core.c:629:20: warning: restricted upf_t degrades to integer
drivers/tty/serial/serial_core.c:632:20: warning: restricted upf_t degrades to integer
drivers/tty/serial/serial_core.c:643:22: warning: invalid assignment: |=
drivers/tty/serial/serial_core.c:643:22: left side has type unsigned int
drivers/tty/serial/serial_core.c:643:22: right side has type restricted upf_t
drivers/tty/serial/serial_core.c:645:22: warning: invalid assignment: |=
drivers/tty/serial/serial_core.c:645:22: left side has type unsigned int
drivers/tty/serial/serial_core.c:645:22: right side has type restricted upf_t
drivers/tty/serial/serial_core.c:647:17: warning: restricted upf_t degrades to integer
drivers/tty/serial/serial_core.c:649:22: warning: invalid assignment: &=
drivers/tty/serial/serial_core.c:649:22: left side has type unsigned int
drivers/tty/serial/serial_core.c:649:22: right side has type restricted upf_t
drivers/tty/serial/serial_core.c:652:20: warning: restricted upf_t degrades to integer
drivers/tty/serial/serial_core.c:655:20: warning: restricted upf_t degrades to integer
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 299245a145,
serial: core: Privatize modem status enable flags, introduced
the upstat_t type and matching bit definitions. The purpose is to
produce sparse warnings if the wrong bit definitions are used
(by warning of implicit integer conversions).
Fix implicit conversion to integer return type from uart_cts_enabled()
and uart_dcd_enabled().
Fixes the following sparse warnings:
drivers/tty/serial/serial_core.c:63:30: warning: incorrect type in return expression (different base types)
drivers/tty/serial/serial_core.c:63:30: expected int
drivers/tty/serial/serial_core.c:63:30: got restricted upstat_t
include/linux/serial_core.h:364:30: warning: incorrect type in return expression (different base types)
include/linux/serial_core.h:364:30: expected bool
include/linux/serial_core.h:364:30: got restricted upstat_t
include/linux/serial_core.h:364:30: warning: incorrect type in return expression (different base types)
include/linux/serial_core.h:364:30: expected bool
include/linux/serial_core.h:364:30: got restricted upstat_t
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Only print one warning when a task is on the read_wait or write_wait
wait queue at final tty release.
Cc: <stable@vger.kernel.org> # 3.4.x+
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Kernel oops can cause the tty to be unreleaseable (for example, if
n_tty_read() crashes while on the read_wait queue). This will cause
tty_release() to endlessly loop without sleeping.
Use a killable sleep timeout which grows by 2n+1 jiffies over the interval
[0, 120 secs.) and then jumps to forever (but still killable).
NB: killable just allows for the task to be rewoken manually, not
to be terminated.
Cc: <stable@vger.kernel.org> # since before 2.6.32
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uart_get_baud_rate() will return baud == 0 if the max rate is set
to the "magic" 38400 rate and the SPD_* flags are also specified.
On the first iteration, if the current baud rate is higher than the
max, the baud rate is clamped at the max (which in the degenerate
case is 38400). On the second iteration, the now-"magic" 38400 baud
rate selects the possibly higher alternate baud rate indicated by
the SPD_* flag. Since only two loop iterations are performed, the
loop is exited, a kernel WARNING is generated and a baud rate of
0 is returned.
Reproducible with:
setserial /dev/ttyS0 spd_hi base_baud 38400
Only perform the "magic" 38400 -> SPD_* baud transform on the first
loop iteration, which prevents the degenerate case from recognizing
the clamped baud rate as the "magic" 38400 value.
Reported-by: Robert Święcki <robert@swiecki.net>
Cc: <stable@vger.kernel.org> # all
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The goldfish_ttys[] array has "goldfish_tty_line_count" number of
elements. It's allocated in goldfish_tty_create_driver(). This test
should be >= instead of >.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/goldfish.c:160:46: warning: Using plain integer as NULL pointer
drivers/tty/goldfish.c:320:22: warning: Using plain integer as NULL pointer
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
n_tty_{read,write} are wait loops with sleeps in. Wait loops rely on
task_struct::state and sleeps do too, since that's the only means of
actually sleeping. Therefore the nested sleeps destroy the wait loop
state.
Fix this by using the new woken_wake_function and wait_woken() stuff,
which registers wakeups in wait and thereby allows shrinking the
task_state::state changes to the actual sleep part.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: oleg@redhat.com
Link: http://lkml.kernel.org/r/20140924082242.323011233@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull slave-dmaengine updates from Vinod Koul:
"For dmaengine contributions we have:
- designware cleanup by Andy
- my series moving device_control users to dmanegine_xxx APIs for
later removal of device_control API
- minor fixes spread over drivers mainly mv_xor, pl330, mmp, imx-sdma
etc"
* 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma: (60 commits)
serial: atmel: add missing dmaengine header
dmaengine: remove FSLDMA_EXTERNAL_START
dmaengine: freescale: remove FSLDMA_EXTERNAL_START control method
carma-fpga: move to fsl_dma_external_start()
carma-fpga: use dmaengine_xxx() API
dmaengine: freescale: add and export fsl_dma_external_start()
dmaengine: add dmaengine_prep_dma_sg() helper
video: mx3fb: use dmaengine_terminate_all() API
serial: sh-sci: use dmaengine_terminate_all() API
net: ks8842: use dmaengine_terminate_all() API
mtd: sh_flctl: use dmaengine_terminate_all() API
mtd: fsmc_nand: use dmaengine_terminate_all() API
V4L2: mx3_camer: use dmaengine_pause() API
dmaengine: coh901318: use dmaengine_terminate_all() API
pata_arasan_cf: use dmaengine_terminate_all() API
dmaengine: edma: check for echan->edesc => NULL in edma_dma_pause()
dmaengine: dw: export probe()/remove() and Co to users
dmaengine: dw: enable and disable controller when needed
dmaengine: dw: always export dw_dma_{en,dis}able
dmaengine: dw: introduce dw_dma_on() helper
...
The atmel serial driver uses dmaengine APIs but never included the dmaengine
header as it was getting inculded thru one of driver headers.
commit 3d588f83e4 - "dmaengine: dw: split
dma-dw.h to platform and private parts" broke this as it moved headers
around. Fix this by doing the right thing to include the dmaengine header
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 08f738be88 (serial: at91: add tx dma support)
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The drivers should use dmaengine_terminate_all() API instead of
accessing the device_control which will be deprecated soon
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Pull scheduler updates from Ingo Molnar:
"The main changes in this cycle were:
- Optimized support for Intel "Cluster-on-Die" (CoD) topologies (Dave
Hansen)
- Various sched/idle refinements for better idle handling (Nicolas
Pitre, Daniel Lezcano, Chuansheng Liu, Vincent Guittot)
- sched/numa updates and optimizations (Rik van Riel)
- sysbench speedup (Vincent Guittot)
- capacity calculation cleanups/refactoring (Vincent Guittot)
- Various cleanups to thread group iteration (Oleg Nesterov)
- Double-rq-lock removal optimization and various refactorings
(Kirill Tkhai)
- various sched/deadline fixes
... and lots of other changes"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
sched/dl: Use dl_bw_of() under rcu_read_lock_sched()
sched/fair: Delete resched_cpu() from idle_balance()
sched, time: Fix build error with 64 bit cputime_t on 32 bit systems
sched: Improve sysbench performance by fixing spurious active migration
sched/x86: Fix up typo in topology detection
x86, sched: Add new topology for multi-NUMA-node CPUs
sched/rt: Use resched_curr() in task_tick_rt()
sched: Use rq->rd in sched_setaffinity() under RCU read lock
sched: cleanup: Rename 'out_unlock' to 'out_free_new_mask'
sched: Use dl_bw_of() under RCU read lock
sched/fair: Remove duplicate code from can_migrate_task()
sched, mips, ia64: Remove __ARCH_WANT_UNLOCKED_CTXSW
sched: print_rq(): Don't use tasklist_lock
sched: normalize_rt_tasks(): Don't use _irqsave for tasklist_lock, use task_rq_lock()
sched: Fix the task-group check in tg_has_rt_tasks()
sched/fair: Leverage the idle state info when choosing the "idlest" cpu
sched: Let the scheduler see CPU idle states
sched/deadline: Fix inter- exclusive cpusets migrations
sched/deadline: Clear dl_entity params when setscheduling to different class
sched/numa: Kill the wrong/dead TASK_DEAD check in task_numa_fault()
...
Pull powerpc updates from Michael Ellerman:
"Here's a first pull request for powerpc updates for 3.18.
The bulk of the additions are for the "cxl" driver, for IBM's Coherent
Accelerator Processor Interface (CAPI). Most of it's in drivers/misc,
which Greg & Arnd maintain, Greg said he was happy for us to take it
through our tree.
There's the usual minor cleanups and fixes, including a bit of noise
in drivers from some of those. A bunch of updates to our EEH code,
which has been getting more testing. Several nice speedups from
Anton, including 20% in clear_page().
And a bunch of updates for freescale from Scott"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (130 commits)
cxl: Fix afu_read() not doing finish_wait() on signal or non-blocking
cxl: Add documentation for userspace APIs
cxl: Add driver to Kbuild and Makefiles
cxl: Add userspace header file
cxl: Driver code for powernv PCIe based cards for userspace access
cxl: Add base builtin support
powerpc/mm: Add hooks for cxl
powerpc/opal: Add PHB to cxl mode call
powerpc/mm: Add new hash_page_mm()
powerpc/powerpc: Add new PCIe functions for allocating cxl interrupts
cxl: Add new header for call backs and structs
powerpc/powernv: Split out set MSI IRQ chip code
powerpc/mm: Export mmu_kernel_ssize and mmu_linear_psize
powerpc/msi: Improve IRQ bitmap allocator
powerpc/cell: Make spu_flush_all_slbs() generic
powerpc/cell: Move data segment faulting code out of cell platform
powerpc/cell: Move spu_handle_mm_fault() out of cell platform
powerpc/pseries: Use new defines when calling H_SET_MODE
powerpc: Update contact info in Documentation files
powerpc/perf/hv-24x7: Simplify catalog_read()
...
- Add pvscsi frontend and backend drivers.
- Remove _PAGE_IOMAP PTE flag, freeing it for alternate uses.
- Try and keep memory contiguous during PV memory setup (reduces
SWIOTLB usage).
- Allow front/back drivers to use threaded irqs.
- Support large initrds in PV guests.
- Fix PVH guests in preparation for Xen 4.5
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Merge tag 'stable/for-linus-3.18-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull Xen updates from David Vrabel:
"Features and fixes:
- Add pvscsi frontend and backend drivers.
- Remove _PAGE_IOMAP PTE flag, freeing it for alternate uses.
- Try and keep memory contiguous during PV memory setup (reduces
SWIOTLB usage).
- Allow front/back drivers to use threaded irqs.
- Support large initrds in PV guests.
- Fix PVH guests in preparation for Xen 4.5"
* tag 'stable/for-linus-3.18-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (22 commits)
xen: remove DEFINE_XENBUS_DRIVER() macro
xen/xenbus: Remove BUG_ON() when error string trucated
xen/xenbus: Correct the comments for xenbus_grant_ring()
x86/xen: Set EFER.NX and EFER.SCE in PVH guests
xen: eliminate scalability issues from initrd handling
xen: sync some headers with xen tree
xen: make pvscsi frontend dependant on xenbus frontend
arm{,64}/xen: Remove "EXPERIMENTAL" in the description of the Xen options
xen-scsifront: don't deadlock if the ring becomes full
x86: remove the Xen-specific _PAGE_IOMAP PTE flag
x86/xen: do not use _PAGE_IOMAP PTE flag for I/O mappings
x86: skip check for spurious faults for non-present faults
xen/efi: Directly include needed headers
xen-scsiback: clean up a type issue in scsiback_make_tpg()
xen-scsifront: use GFP_ATOMIC under spin_lock
MAINTAINERS: Add xen pvscsi maintainer
xen-scsiback: Add Xen PV SCSI backend driver
xen-scsifront: Add Xen PV SCSI frontend driver
xen: Add Xen pvSCSI protocol description
xen/events: support threaded irqs for interdomain event channels
...
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Merge tag 'locks-v3.18-1' of git://git.samba.org/jlayton/linux
Pull file locking related changes from Jeff Layton:
"This release is a little more busy for file locking changes than the
last:
- a set of patches from Kinglong Mee to fix the lockowner handling in
knfsd
- a pile of cleanups to the internal file lease API. This should get
us a bit closer to allowing for setlease methods that can block.
There are some dependencies between mine and Bruce's trees this cycle,
and I based my tree on top of the requisite patches in Bruce's tree"
* tag 'locks-v3.18-1' of git://git.samba.org/jlayton/linux: (26 commits)
locks: fix fcntl_setlease/getlease return when !CONFIG_FILE_LOCKING
locks: flock_make_lock should return a struct file_lock (or PTR_ERR)
locks: set fl_owner for leases to filp instead of current->files
locks: give lm_break a return value
locks: __break_lease cleanup in preparation of allowing direct removal of leases
locks: remove i_have_this_lease check from __break_lease
locks: move freeing of leases outside of i_lock
locks: move i_lock acquisition into generic_*_lease handlers
locks: define a lm_setup handler for leases
locks: plumb a "priv" pointer into the setlease routines
nfsd: don't keep a pointer to the lease in nfs4_file
locks: clean up vfs_setlease kerneldoc comments
locks: generic_delete_lease doesn't need a file_lock at all
nfsd: fix potential lease memory leak in nfs4_setlease
locks: close potential race in lease_get_mtime
security: make security_file_set_fowner, f_setown and __f_setown void return
locks: consolidate "nolease" routines
locks: remove lock_may_read and lock_may_write
lockd: rip out deferred lock handling from testlock codepath
NFSD: Get reference of lockowner when coping file_lock
...
cycle:
- Increase the default ARCH_NR_GPIO from 256 to 512. This
was done to avoid having a custom <asm/gpio.h> header for
the x86 architecture - GPIO is custom and complicated
enough as it is already! We want to move to a radix to
store the descriptors going forward, and finally get rid
of this fixed array size altogether.
- Endgame patching of the gpio_remove() semantics initiated
by Abdoulaye Berthe. It is not accepted by the system that
the removal of a GPIO chip fails during e.g. reboot or
shutdown, and therefore the return value has now painfully
been refactored away. For special cases like GPIO expanders
on a hot-pluggable bus like USB, we may later add some
gpiochip_try_remove() call, but for the cases we have now,
return values are moot.
- Some incremental refactoring of the gpiolib core and ACPI
GPIO library for more descriptor usage.
- Refactor the chained IRQ handler set-up method to handle
also threaded, nested interrupts and set up the parent IRQ
correctly. Switch STMPE and TC3589x drivers to use this
registration method.
- Add a .irq_not_threaded flag to the struct gpio_chip, so
that also GPIO expanders that block but are still not
using threaded IRQ handlers.
- New drivers for the ARM64 X-Gene SoC GPIO controller.
- The syscon GPIO driver has been improved to handle the
"DSP GPIO" found on the TI Keystone 2 SoC:s.
- ADNP driver switched to use gpiolib irqchip helpers.
- Refactor the DWAPB driver to support being instantiated
from and MFD cell (platform device).
- Incremental feature improvement in the Zynq, MCP23S08,
DWAPB, OMAP, Xilinx and Crystalcove drivers.
- Various minor fixes.
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Merge tag 'gpio-v3.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO changes from Linus Walleij:
"This is the bulk of GPIO changes for the v3.18 development cycle:
- Increase the default ARCH_NR_GPIO from 256 to 512. This was done
to avoid having a custom <asm/gpio.h> header for the x86
architecture - GPIO is custom and complicated enough as it is
already! We want to move to a radix to store the descriptors going
forward, and finally get rid of this fixed array size altogether.
- Endgame patching of the gpio_remove() semantics initiated by
Abdoulaye Berthe. It is not accepted by the system that the
removal of a GPIO chip fails during eg reboot or shutdown, and
therefore the return value has now painfully been refactored away.
For special cases like GPIO expanders on a hot-pluggable bus like
USB, we may later add some gpiochip_try_remove() call, but for the
cases we have now, return values are moot.
- Some incremental refactoring of the gpiolib core and ACPI GPIO
library for more descriptor usage.
- Refactor the chained IRQ handler set-up method to handle also
threaded, nested interrupts and set up the parent IRQ correctly.
Switch STMPE and TC3589x drivers to use this registration method.
- Add a .irq_not_threaded flag to the struct gpio_chip, so that also
GPIO expanders that block but are still not using threaded IRQ
handlers.
- New drivers for the ARM64 X-Gene SoC GPIO controller.
- The syscon GPIO driver has been improved to handle the "DSP GPIO"
found on the TI Keystone 2 SoC:s.
- ADNP driver switched to use gpiolib irqchip helpers.
- Refactor the DWAPB driver to support being instantiated from and
MFD cell (platform device).
- Incremental feature improvement in the Zynq, MCP23S08, DWAPB, OMAP,
Xilinx and Crystalcove drivers.
- Various minor fixes"
* tag 'gpio-v3.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (52 commits)
gpio: pch: Build context save/restore only for PM
pinctrl: abx500: get rid of unused variable
gpio: ks8695: fix 'else should follow close brace '}''
gpio: stmpe: add verbose debug code
gpio: stmpe: fix up interrupt enable logic
gpio: staticize xway_stp_init()
gpio: handle also nested irqchips in the chained handler set-up
gpio: set parent irq on chained handlers
gpiolib: irqchip: use irq_find_mapping while removing irqchip
gpio: crystalcove: support virtual GPIO
pinctrl: bcm281xx: make Kconfig dependency more strict
gpio: kona: enable only on BCM_MOBILE or for compile testing
gpio, bcm-kona, LLVMLinux: Remove use of __initconst
gpio: Fix ngpio in gpio-xilinx driver
gpio: dwapb: fix pointer to integer cast
gpio: xgene: Remove unneeded #ifdef CONFIG_OF guard
gpio: xgene: Remove unneeded forward declation for struct xgene_gpio
gpio: xgene: Fix missing spin_lock_init()
gpio: ks8695: fix switch case indentation
gpiolib: add irq_not_threaded flag to gpio_chip
...
Here's the big tty/serial driver patchset for 3.18-rc1.
Lots of little things in here, some good work from Peter Hurley on the
tty core, and in lots of drivers. There are also lots of other driver
updates in here as well, full details in the changelog below.
All have been in the linux-next tree for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
"Here's the big tty/serial driver patchset for 3.18-rc1.
Lots of little things in here, some good work from Peter Hurley on the
tty core, and in lots of drivers. There are also lots of other driver
updates in here as well, full details in the changelogs.
All have been in the linux-next tree for a while"
* tag 'tty-3.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (99 commits)
Revert "serial/core: Initialize the console pm state"
tty: serial: 8250: use 32bit variable for rpm_tx_active
tty: serial: msm: Add earlycon support
serial/core: Initialize the console pm state
serial: asc: Conditionally use readl_relaxed (COMPILE_TEST)
serial: of-serial: add PM suspend/resume support
m68k: AMIGA_BUILTIN_SERIAL should depend on TTY
asm/uapi: Add definition of TIOC[SG]RS485
tty/metag_da: Add console_poll module parameter
serial: 8250_pci: remove rts_n override from Baytrail quirk
serial: cadence: Add generic earlycon support
serial: imx: change the wait even to interruptiable
serial: imx: terminate the RX DMA when the UART is suspending
serial: imx: fix throttle/unthrottle callbacks for hardware assisted flow control
serial: 8250: Add Quark X1000 to 8250_pci.c
tty: omap-serial: pull out calculation from baud_is_mode16
tty: omap-serial: fix division by zero
xen_hvc: no reason to write the type key on xenstore
tty: serial: 8250_core: remove UART_IER_RDI in serial8250_stop_rx()
tty: serial: 8250_core: use the ->line argument as a hint in serial8250_find_match_or_unused()
...
Cheers,
Rusty.
PS. My virtio-next tree is empty: DaveM took the patches I had. There might
be a virtio-rng starvation fix, but so far it's a bit voodoo so I will
get to that in the next two days or it will wait.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module update from Rusty Russell:
"Nothing major: support for compressing modules, and auto-tainting
params.
PS. My virtio-next tree is empty: DaveM took the patches I had. There
might be a virtio-rng starvation fix, but so far it's a bit voodoo
so I will get to that in the next two days or it will wait"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
moduleparam: Resolve missing-field-initializer warning
kbuild: handle module compression while running 'make modules_install'.
modinst: wrap long lines in order to enhance cmd_modules_install
modsign: lookup lines ending in .ko in .mod files
modpost: simplify file name generation of *.mod.c files
modpost: reduce visibility of symbols and constify r/o arrays
param: check for tainting before calling set op.
drm/i915: taint the kernel if unsafe module parameters are set
module: add module_param_unsafe and module_param_named_unsafe
module: make it possible to have unsafe, tainting module params
module: rename KERNEL_PARAM_FL_NOARG to avoid confusion
The DEFINE_XENBUS_DRIVER() macro looks a bit weird and causes sparse
errors.
Replace the uses with standard structure definitions instead. This is
similar to pci and usb device registration.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
This reverts commit a86713b153.
Kevin Hilman writes:
Multiple boot failures on ARM[1] were bisected down to this
patch.
How was this patch tested, and on which platforms?
Also, the changelog states that this should be done only for
UART_CAP_SLEEP, but the patch does it for every UART.
Greg, I suggest this patch be dropped from tty-next until it has
been better described and tested.
[1] http://lists.linaro.org/pipermail/kernel-build-reports/2014-October/005550.html
Reported-by: Kevin Hilman <khilman@kernel.org>
Cc: Sudhir Sreedharan <ssreedharan@mvista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no need for yet another copy of the command line, just
use boot_command_line like everyone else.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Add support for DT based and command line based early console on platforms
with the msm serial hardware.
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For console devices having UART_CAP_SLEEP capability, the uart_pm_state has
to be initialized to UART_PM_STATE_ON. Otherwise the LCR regiser values
are reinitialized when uart_change_pm is called from uart_configure_port.
Signed-off-by: Sudhir Sreedharan <ssreedharan@mvista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 08177ece59 ("serial: asc: Adopt readl_/writel_relaxed()) is
regressing the m68k allmodconfig build. This is due to the unconditional
use of readl_relaxed() which, although documented, does not currently
exist for m68k.
This is trivially fixable for st-asc because we can just update the
asc_in() accessor to make this conditional.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Srinivas Kandagatla <srinivas.kandagatla@gmail.com>
Cc: Maxime Coquelin <maxime.coquelin@st.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds PM suspend/resume support for the of-serial driver
to provide power management support on devices attatched to it.
Signed-off-by: Jingchang Lu <jingchang.lu@freescale.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently the metag_da console channel is write only, it doesn't get
polled for incoming data. This is for performance & latency reasons as
polling blocks the processor for a significant amount of time waiting
for the JTAG probe to respond to the request and restart the thread.
This means that the console channel cannot be used for a login prompt,
so ttyDA2 is usually used instead.
In a virtual environment with a virtual DA such as QEMU however the
polling is much cheaper as the request can be handled immediately. It is
useful to be able to enable polling in such an environment in order to
get both the kernel log and a usable login prompt on the same DA
channel.
Add a console_poll module parameter which allows polling to be enabled
for the console channel. It defaults to off as that is the current
behaviour for good reason on real hardware.
It can be enabled by appending metag_da.console_poll to the kernel
command line.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It should not be used together with Auto Flow Control, and
Auto Flow Control is always enabled on Baytrail.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add earlycon support for the cadence serial port.
This is based on recent patches:
"tty/serial: pl011: add generic earlycon support"
(sha1: 0d3c673e78)
"tty/serial: add arm/arm64 semihosting earlycon"
(sha1: d50d7269eb)
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The wait_event() makes the application hang for ever in the following case:
[1] the hardware flow control is enabled.
[2] the other end (or the remote end) is terminated, and the TX is still
waiting for the hardware flow control signal to become asserted.
This patch fixes it by changing the wait_event to wait_event_interruptible.
Signed-off-by: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the uart port is suspending, the RX data is useless.
So in this case, we can terminate the RX DMA right now.
Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
when the 'CTSC' bit is negated. 'CTS' has no function when 'CTSC' is asserted.
0: The CTS pin is high (inactive)
1: The CTS pin is low (active)
For throttle, it needs to clear 'CTS' and 'CTSC' bits.
For unthrottle, it needs to enable 'CTS' and 'CTSC' bits.
The patch just fix the issue.
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Quark X1000 contains two designware derived 8250 serial ports.
Each port has a unique PCI configuration space consisting of
BAR0:UART BAR1:DMA respectively.
Unlike the standard 8250 the register width is 32 bits for RHR,IER etc
The Quark UART has a fundamental clock @ 44.2368 MHz allowing for a
bitrate of up to about 2.76 megabits per second.
This patch enables standard 8250 mode
Signed-off-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To determine the correct divisor, we need to know the difference between
the desired baud rate and the actual baud rate. The calculation for this
difference is implemented twice within omap_serial_baud_is_mode16().
Pull out the calculation for easier maintenance.
While at it, remove the CamelCasing from the variable names.
Signed-off-by: Frans Klaver <frans.klaver@xsens.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the chosen baud rate is large enough (e.g. 3.5 megabaud), the
calculated n values in serial_omap_is_baud_mode16() may become 0. This
causes a division by zero when calculating the difference between
calculated and desired baud rates. To prevent this, cap the n13 and n16
values on 1.
Division by zero in kernel.
[<c00132e0>] (unwind_backtrace) from [<c00112ec>] (show_stack+0x10/0x14)
[<c00112ec>] (show_stack) from [<c01ed7bc>] (Ldiv0+0x8/0x10)
[<c01ed7bc>] (Ldiv0) from [<c023805c>] (serial_omap_baud_is_mode16+0x4c/0x68)
[<c023805c>] (serial_omap_baud_is_mode16) from [<c02396b4>] (serial_omap_set_termios+0x90/0x8d8)
[<c02396b4>] (serial_omap_set_termios) from [<c0230a0c>] (uart_change_speed+0xa4/0xa8)
[<c0230a0c>] (uart_change_speed) from [<c0231798>] (uart_set_termios+0xa0/0x1fc)
[<c0231798>] (uart_set_termios) from [<c022bb44>] (tty_set_termios+0x248/0x2c0)
[<c022bb44>] (tty_set_termios) from [<c022c17c>] (set_termios+0x248/0x29c)
[<c022c17c>] (set_termios) from [<c022c3e4>] (tty_mode_ioctl+0x1c8/0x4e8)
[<c022c3e4>] (tty_mode_ioctl) from [<c0227e70>] (tty_ioctl+0xa94/0xb18)
[<c0227e70>] (tty_ioctl) from [<c00cf45c>] (do_vfs_ioctl+0x4a0/0x560)
[<c00cf45c>] (do_vfs_ioctl) from [<c00cf568>] (SyS_ioctl+0x4c/0x74)
[<c00cf568>] (SyS_ioctl) from [<c000e480>] (ret_fast_syscall+0x0/0x30)
Signed-off-by: Frans Klaver <frans.klaver@xsens.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The backend type is chosen by the toolstack. Regardless, the frontend
should not care, especially given that it cannot have an effect as the
backend is started before this code is run.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial8250_do_startup() adds UART_IER_RDI and UART_IER_RLSI to ier.
serial8250_stop_rx() should remove both.
This is what the serial-omap driver has been doing and is now moved to
the 8250-core since it does no look to be *that* omap specific.
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tony noticed that the old omap-serial driver picked the uart "number"
based on the hint given from device tree or platform device's id.
The 8250 based omap driver doesn't do this because the core code does
not honour the ->line argument which is passed by the driver.
This patch aims to keep the same behaviour as with omap-serial. The
function will first try to use the line suggested ->line argument and
then fallback to the old strategy in case the port is taken.
That means the the third uart will always be ttyS2 even if the previous
two have not been enabled in DT.
Reviewed-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The serial8250_do_startup() function unconditionally clears the
interrupts and for that it reads from the RX-FIFO without checking if
there is a byte in the FIFO or not. This works fine on OMAP4+ HW like
AM335x or DRA7.
OMAP3630 ES1.1 (which means probably all OMAP3 and earlier) does not like
this:
|Unhandled fault: external abort on non-linefetch (0x1028) at 0xfb020000
|Internal error: : 1028 [#1] ARM
|Modules linked in:
|CPU: 0 PID: 1 Comm: swapper Not tainted 3.16.0-00022-g7edcb57-dirty #1213
|task: de0572c0 ti: de058000 task.ti: de058000
|PC is at mem32_serial_in+0xc/0x1c
|LR is at serial8250_do_startup+0x220/0x85c
|Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
|Control: 10c5387d Table: 80004019 DAC: 00000015
|[<c03051d4>] (mem32_serial_in) from [<c0307fe8>] (serial8250_do_startup+0x220/0x85c)
|[<c0307fe8>] (serial8250_do_startup) from [<c0309e00>] (omap_8250_startup+0x5c/0xe0)
|[<c0309e00>] (omap_8250_startup) from [<c030863c>] (serial8250_startup+0x18/0x2c)
|[<c030863c>] (serial8250_startup) from [<c030394c>] (uart_startup+0x78/0x1d8)
|[<c030394c>] (uart_startup) from [<c0304678>] (uart_open+0xe8/0x114)
|[<c0304678>] (uart_open) from [<c02e9e10>] (tty_open+0x1a8/0x5a4)
Reviewed-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While comparing the OMAP-serial and the 8250 part of this I noticed that
the latter does not use run time-pm. Here are the pieces. It is
basically a get before first register access and a last_busy + put after
last access. This has to be enabled from userland _and_ UART_CAP_RPM is
required for this.
The runtime PM can usually work transparently in the background however
there is one exception to this: After serial8250_tx_chars() completes
there still may be unsent bytes in the FIFO (depending on CPU speed vs
baud rate + flow control). Even if the TTY-buffer is empty we do not
want RPM to disable the device because it won't send the remaining
bytes. Instead we leave serial8250_tx_chars() with RPM enabled and wait
for the FIFO empty interrupt. Once we enter serial8250_tx_chars() with
an empty buffer we know that the FIFO is empty and since we are not going
to send anything, we can disable the device.
That xchg() is to ensure that serial8250_tx_chars() can be called
multiple times and only the first invocation will actually invoke the
runtime PM function. So that the last invocation of __stop_tx() will
disable runtime pm.
NOTE: do not enable RPM on the device unless you know what you do! If
the device goes idle, it won't be woken up by incomming RX data _unless_
there is a wakeup irq configured which is usually the RX pin configure
for wakeup via the reset module. The RX activity will then wake up the
device from idle. However the first character is garbage and lost. The
following bytes will be received once the device is up in time. On the
beagle board xm (omap3) it takes approx 13ms from the first wakeup byte
until the first byte that is received properly if the device was in
core-off.
v5…v8:
- drop RPM from serial8250_set_mctrl() it will be used in
restore path which already has RPM active and holds
dev->power.lock
v4…v5:
- add a wrapper around rpm function and introduce UART_CAP_RPM
to ensure RPM put is invoked after the TX FIFO is empty.
v3…v4:
- added runtime to the console code
- removed device_may_wakeup() from serial8250_set_sleep()
Cc: mika.westerberg@linux.intel.com
Reviewed-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The OMAP UART provides support for HW assisted flow control. What is
missing is the support to throttle / unthrottle callbacks which are used
by the omap-serial driver at the moment.
This patch adds the callbacks. It should be safe to add them since they
are only invoked from the serial_core (uart_throttle()) if the feature
flags are set.
Reviewed-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While transmitting a START/STOP char for tcflow(TCION/TCIOFF), prevent
a termios change. Otherwise, a garbage in-band flow control char
may be sent, if the termios change overlaps the transmission setup.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Relocate the file-scope function, send_prio_char(), as a global
helper tty_send_xchar(). Remove the global declarations for
tty_write_lock()/tty_write_unlock(), as these are file-scope only now.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use newly-introduced tty->flow_lock to serialize updates to
tty->flow_stopped (via tcflow()) and with concurrent tty flow
control changes from other sources.
Merge the storage for ->stopped and ->flow_stopped, now that both
flags are serialized by ->flow_lock.
The padding bits are necessary to force the compiler to allocate the
type specified; otherwise, gcc will ignore the type specifier and
allocate the minimum number of bytes necessary to store the bitfield.
In turn, this would allow Alpha EV4 and EV5 cpus to corrupt adjacent
byte storage because those cpus use RMW to store byte and short data.
gcc versions < 4.7.2 will also corrupt storage adjacent to bitfields
smaller than unsigned long on ia64, ppc64, hppa64 and sparc64, thus
requiring more than unsigned int storage (which would otherwise be
sufficient to workaround the Alpha non-atomic byte/short storage problem).
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a master pty is set to packet mode, flow control changes to
the slave pty cause notifications to the master pty via reads and
polls. However, these tests are occurring for all ttys, not
just ptys.
Implement flow control packet mode notifications in the pty driver.
Only the slave side implements the flow control handlers since
packet mode is asymmetric; the master pty receives notifications
for slave-side changes, but not vice versa.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Without serialization, the flow control state can become inverted
wrt. the actual hardware state. For example,
CPU 0 | CPU 1
stop_tty() |
lock ctrl_lock |
tty->stopped = 1 |
unlock ctrl_lock |
| start_tty()
| lock ctrl_lock
| tty->stopped = 0
| unlock ctrl_lock
| driver->start()
driver->stop() |
In this case, the flow control state now indicates the tty has
been started, but the actual hardware state has actually been stopped.
Introduce tty->flow_lock spinlock to serialize tty flow control changes.
Split out unlocked __start_tty()/__stop_tty() flavors for use by
ioctl(TCXONC) in follow-on patch.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uart_set_termios() is called with interrupts enabled; no need to
save and restore the interrupt state when taking the uart port lock.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 64851636d5,
serial: bfin-uart: Remove ASYNC_CTS_FLOW flag for hardware automatic CTS,
open-codes uart_handle_cts_change() when CONFIG_SERIAL_BFIN_HARD_CTSRTS
to skip start and stop tx.
But the CTS interrupt handler _still_ calls uart_handle_cts_change();
only call uart_handle_cts_change() if !CONFIG_SERIAL_BFIN_HARD_CTSRTS.
cc: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty->hw_stopped is not used by the tty core and is thread-unsafe;
hw_stopped is a member of a bitfield whose fields are updated
non-atomically and no lock is suitable for serializing updates.
Replace serial core usage of tty->hw_stopped with uport->hw_stopped.
Use int storage which works around Alpha EV4/5 non-atomic byte storage,
since uart_port uses different locks to protect certain fields within the
structure.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The serial core uses the tty port flags, ASYNC_CTS_FLOW and
ASYNC_CD_CHECK, to track whether CTS and DCD changes should be
ignored or handled. However, the tty port flags are not safe for
atomic bit operations and no lock provides serialized updates.
Introduce the struct uart_port status field to track CTS and DCD
enable states, and serialize access with uart port lock. Substitute
uart_cts_enabled() helper for tty_port_cts_enabled().
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The serial core provides two helper functions, uart_handle_dcd_change()
and uart_handle_cts_change(), for UART drivers to use at interrupt
time. The serial core expects the UART driver to hold the uart port lock
when calling these helpers to prevent state corruption.
If lockdep enabled, trigger a warning if the uart port lock is not held
when calling these helper functions.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We are trying to smoke out the use of the return value from
gpiochip_remove() from the kernel, this has been missed.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch fixes COMPILE_TEST build of serial_mctrl_gpio module for
architectures with custom termios.h header.
sparc64:allmodconfig:
In file included from drivers/tty/serial/serial_mctrl_gpio.c:21:0:
include/uapi/asm-generic/termios.h:22:8: error: redefinition of 'struct termio'
./arch/sparc/include/uapi/asm/termbits.h:16:8: note: originally defined here
make[3]: *** [drivers/tty/serial/serial_mctrl_gpio.o] Error 1
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
this remove all reference to gpio_remove retval in all driver
except pinctrl and gpio. the same thing is done for gpio and
pinctrl in two different patches.
Signed-off-by: Abdoulaye Berthe <berthe.ab@gmail.com>
Acked-by: Michael Büsch <m@bues.ch>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add new PCI IDs to cover newer Intel SoCs such as Braswell.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
That field has been deprecated in favour of getting the necessary information
from ACPI or DT.
However, we still need to deal systems that are PCI only (no ACPI to back up)
like Intel Bay Trail. In order to support such systems, we explicitly bind
setup() to the appropriate DMA filter function and its corresponding parameter.
Then when serial8250_request_dma() doesn't find the channel via ACPI or DT, it
falls back to use the given filter function.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The device has a highspeed register which influences the calcualtion
of the divisor. The chip lacks support for some baudrates. When requested,
we set the divisor to the next smaller baudrate and adjust the c_cflag
accordingly.
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The architectures supported by this driver, arm and sh, have expensive
implementations of writel(), reliant on spin locks and explicit L2 cache
management. These architectures provide a cheaper writel_relaxed() which
is much better suited to peripherals that do not perform DMA. The
situation with readl()/readl_relaxed()is similar although less acute.
This driver does not use DMA and will be more power efficient and more
robust (due to absence of spin locks during console I/O) if it uses the
relaxed variants.
The driver supports COMPILE_TEST and therefore falls back to writel()
when writel_relaxed() does not exist.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@gmail.com>
Cc: Maxime Coquelin <maxime.coquelin@st.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: kernel@stlinux.com
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The patch fixes the following build error of CLPS711X serial driver for
targets without GPIOLIB support:
>> drivers/tty/serial/serial_mctrl_gpio.c:44:6: error: redefinition of 'mctrl_gpio_set'
void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
^
In file included from drivers/tty/serial/serial_mctrl_gpio.c:23:0:
drivers/tty/serial/serial_mctrl_gpio.h:80:6: note: previous definition of 'mctrl_gpio_set' was here
void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
^
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit: e676253b19 [3/21] serial/8250: Add
support for RS485 IOCTLs, adds a building error on arch m32r.
All error/warnings:
drivers/tty/serial/8250/8250_core.c: In function 'serial8250_ioctl':
>> drivers/tty/serial/8250/8250_core.c:2859:3: error: implicit declaration of function 'copy_from_user' [-Werror=implicit-function-declaration]
if (copy_from_user(&rs485_config, (void __user *)arg,
^
>> drivers/tty/serial/8250/8250_core.c:2871:3: error: implicit declaration of function 'copy_to_user' [-Werror=implicit-function-declaration]
if (copy_to_user((void __user *)arg, &up->rs485,
^
cc1: some warnings being treated as errors
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
security_file_set_fowner always returns 0, so make it f_setown and
__f_setown void return functions and fix up the error handling in the
callers.
Cc: linux-security-module@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The tx_empty() callback currently checks the TXEMPTY bit in the interrupt
status register to decided whether the FIFO should be reported as empty or
not. The bit in this register gets set when the FIFO state transitions from
non-empty to empty but is cleared again in the interrupt handler. This means
it is not suitable to be used to decided whether the FIFO is currently empty
or not. Instead use the TXEMPTY bit from the status register which will be
set as long as the FIFO is empty.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In set_termios(), interrupts where not disabled if UART_ENABLE_MS() was
false.
Tested on at91sam9g35.
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Cc: stable <stable@vger.kernel.org> # >= 3.16
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Another new ACPI identifier for the 8250 dw bindings to cover newer Intel
SoCs such as Braswell.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The OMAP version of the 8250 can actually use 1:1 serial8250_startup().
However it needs to be extended by a wake up irq which should to be
requested & enabled at ->startup() time and disabled at ->shutdown() time.
v2…v3: properly copy callbacks
v1…v2: add shutdown callback
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no way to access a struct uart_8250_port for a specific
line. This is only required outside of the 8250/uart callbacks like for
devices' suspend & remove callbacks. For those the 8250-core provides a
wrapper like serial8250_unregister_port() which passes the struct
to the proper function based on the line argument.
For run time suspend I need access to this struct not only to make
serial_out() work but also to properly restore up->ier and up->mcr.
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many local variables were given the same name as a global. This
is valid, but generates many shadow warnings in W=2 builds. Resolve
them by changing the local names. Also change local variables
named "up" because they shadow the semaphore "up" function. Also
moved the outer declaration of the variable "a" because it is
only used in one block, and that resolves all of the shadow warnings
for the other declarations of "a" that have different types.
Change diacr => dia, kbd => kb, rep => rpt, up => udp.
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Current code relies on the UART clock pre-divisor to be already
configured in the baud rate register. Calculate it in the driver
and set explicitly instead, also return the "real" effective baud
rate, which is generally slightly different from the requested value.
While at this, also ensure that break signal timing is updated when
baud rate changes.
Signed-off-by: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds simple polling functions for single-character transmit
and receive, as used by kgdb.
Signed-off-by: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Newer WonderMedia chips introduced another flag in the UART line control
register, which controls whether RTS/CTS signalling should be handled in
the driver or by the hardware itself.
This patch ensures that the kernel can control RTS/CTS (including
disabling it altogether) by forcing this flag to software mode on affected
chips (only WM8880 so far).
Also remove the redundant copy of the binding doc, while we are here.
Signed-off-by: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
At present this console is optionally registered by NULL checking
arch_kgdb_ops.enable_nmi. In practice this requires the architecture
dependant code to implement some kind of control (e.g. module arguments)
to enable/disable this feature.
The kernel already provides us the perfectly adequate console= argument
to enable/disable consoles. Let's use that instead!
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Universally adopt container_of() for all pointer conversion from
uart_port to uart_amba_port.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Looking at the get_poll_char() function of the 8250.c serial driver,
we learn:
* poll_get_char() doesn't have to save/disable/restore the interrupt
registers. No interrupt handling is needed in this function at all.
Remove it.
* Don't block in case there is no data available. So instead blocking
in the do {} while loop, just return with NO_POLL_CHAR, immediately .
Additionally, while the i.MX6 register URXD[7-0] contain the RX_DATA,
the upper bits of this register (URXD[15-10]) might contain some
control flags. To ensure that these are not returned with the data
read, just mask out URXD[7-0].
These changes fix the 'hang' working with kdb:
$ echo ttymxc3 > /sys/module/kgdboc/parameters/kgdboc
$ echo g >/proc/sysrq-trigger
[0]kdb> help
...
<hang>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Prepare for spin lock assertion; move non-trivial assignment into
function body.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Existing callers of serial8250_modem_status() [1] hold the uart port
lock; document.
[1] In-tree callers of serial8250_modem_status()
drivers/tty/serial/8250/8250_fsl.c
fsl8250_handle_irq()
drivers/tty/serial/8250/8250_core.c
serial8250_handle_irq()
serial8250_console_write()
serial8250_get_mctrl() *
* Call graphs for callers of serial8250_get_mctrl() from the function
which acquires the uart port lock
drivers/tty/serial/serial_core.c
uart_port_startup()
uart_tiocmget()
uart_set_termios()
uart_carrier_raised()
ops->get_mctrl() ---> serial8250_get_mctrl()
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If CONFIG_SERIAL_BFIN_CTSRTS is set, compile fails because of missing
declarations for the gpio_* api. Include necessary header.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The serial core may call the UART driver's start_tx() even if
tx is stopped; the UART driver must verify tx should be enabled
before transmitting.
Reported-by: Sam Ravnborg <sam@ravnborg.org>
cc: David S. Miller <davem@davemloft.net>
cc: <sparclinux@vger.kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mpc52xx_uart_send_xchar() is _identical_ to the default serial core
x_char handling behavior in uart_send_xchar().
Remove mpc52xx_uart_send_xchar().
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
START_CHAR() & STOP_CHAR() can be disabled if set to '\0'
(__DISABLED_CHAR). UART drivers which define a send_xchar()
handler must not transmit __DISABLED_CHAR.
Document requirement.
Affected drivers:
sunsab
sunhv
cc: David S. Miller <davem@davemloft.net>
cc: <sparclinux@vger.kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uart_unthrottle() attempts to avoid sending START and the previous
x_char if the previous x_char has not yet been sent. However, this
optimization could leave the sender in a throttled state; for example,
if the sender is throttled and this unthrottle coincides with a manual
tcflow(TCION) from user-space, then neither START would be sent.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The UART driver is expected to clear port->x_char after
transmission while holding the port->lock. However, the serial
core fails to take the port->lock before assigning port->xchar.
This allows for the following race
CPU 0 | CPU 1
|
| serial8250_handle_irq
| ...
| serial8250_tx_chars
| if (port->x_char)
| serial_out(up, UART_TX, port->x_char)
uart_send_xchar |
port->x_char = ch |
| port->x_char = 0
port->ops->start_tx() |
|
The x_char on CPU 0 will never be sent.
Take the port->lock in uart_send_xchar() before assigning port->x_char.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The serial core expects the UART driver to transmit x_char
(START/STOP chars) even if tx is stopped and before data already
in the tx ring buffer if possible. Also, sending x_char must
not cause additional data in the tx ring buffer to transmit
if tx is stopped.
Cause x_char to be transmitted before any other data is sent.
Auto-stop tx if the tx ring buffer is empty or tx should be stopped.
Only perform one write wakeup if tx ring buffer space is below
threshold.
x_char handling in DMA mode is still broken; add FIXME.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 06aa82e498.
This commit purports to enable auto CTS flow control for the 8250
UART driver. However, the 8250 UART driver already supports auto
CTS flow control via UART_CAP_AFE and UART_CAP_EFR. Indeed, this
patch introduces another DT attribute for which an existing firmware
flag already exists ("auto-flow-control"). Furthermore, the use of
UPF_HARD_FLOW requires the UART driver to define .throttle and
.unthrottle methods, neither of which are defined for the 8250 UART
driver (which will result in a NULL ptr dereference). Finally, this patch
supposes to fix existing bugs in the serial core for auto CTS-enabled
hardware, but does not include the class of hardware for which these
bugs exist.
CC: Murali Karicheri <m-karicheri2@ti.com>
CC: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Delete successive assignments to the same location.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
expression i;
@@
*i = ...;
i = ...;
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The SoC has four fully functional UARTs which use the same programming
model. They are named UART_A, UART_B, UART_C and UART_AO (Always-On)
which cannot be powered off.
Signed-off-by: Carlo Caione <carlo@caione.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Several architectures (e.g. microblaze, um, and score) have already have
extern 'setup_memory', so need use 'nozomi_setup_memory' instead of, or
will cause compiling issue.
The related error (with allmodconfig for microblaze):
CC [M] drivers/tty/nozomi.o
drivers/tty/nozomi.c:526:13: error: conflicting types for 'setup_memory'
static void setup_memory(struct nozomi *dc)
^
In file included from include/linux/mm.h:51:0,
from ./arch/microblaze/include/asm/io.h:17,
from include/linux/io.h:22,
from include/linux/pci.h:31,
from drivers/tty/nozomi.c:46:
./arch/microblaze/include/asm/pgtable.h:569:6: note: previous declaration of 'setup_memory' was here
void setup_memory(void);
^
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no need to init .owner field.
Based on the patch from Peter Griffin <peter.griffin@linaro.org>
"mmc: remove .owner field for drivers using module_platform_driver"
This patch removes the superflous .owner field for drivers which
use the module_platform_driver API, as this is overriden in
platform_driver_register anyway."
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no need to init .owner field.
Based on the patch from Peter Griffin <peter.griffin@linaro.org>
"mmc: remove .owner field for drivers using module_platform_driver"
This patch removes the superflous .owner field for drivers which
use the module_platform_driver API, as this is overriden in
platform_driver_register anyway."
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The symbol is defined in drivers/tty/serial/8250/Kconfig as
"SERIAL_8250", not just "8250".
Signed-off-by: Daniele Forsi <dforsi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the N_TTY line discipline receives data and wakes readers to
process the input, polling writers are also mistakenly woken. This
is because, although readers and writers are differentiated by
different wait queues (tty->read_wait & tty->write_wait), both
wait queues are polled together. Thus, reader wakeups without poll
flags still cause poll(POLLOUT) to wakeup.
For received data, wakeup readers with POLLIN. Preserve the
unspecific wakeup in n_tty_packet_mode_flush(), as this action
should flag both POLLIN and POLLOUT.
Fixes epoll_wait() for edge-triggered EPOLLOUT.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Frank reports that after continuing in kgdb the RX stale event
doesn't occur until after the RX fifo is filled up with exactly
the amount of characters programmed for the RX watermark (in this
case it's 48). To read a single character from the uartdm
hardware we force a stale event so that any characters in the RX
packing buffer are flushed into the RX fifo immediately instead
of waiting for a stale timeout or for the fifo to fill. Forcing
that stale event asserts the stale interrupt but we never clear
that interrupt via UART_CR_CMD_RESET_STALE_INT in the polling
functions. So when kgdb continues the stale interrupt is left
pending in the hardware and we don't timeout with a stale event,
like we usually would if a user typed one character on the
console, until the reset stale interrupt and stale event commands
are sent. Frank could get things working again by running
handle_rx_dm(). By putting enough characters into the fifo he
could trigger a watermark interrupt, and thus cause
handle_rx_dm() to run finally resetting the stale interrupt
and enabling the stale event so that single characters would
cause timeouts again.
The fix is to just do what the interrupt routine was doing all
along and clear the stale interrupt and enable the event again.
Doing this also smooths over any differences in the fifo behavior
between v1.3 and v1.4 hardware allowing us to skip forcing the
uart into single character mode.
Reviewed-by: Frank Rowand <frank.rowand@sonymobile.com>
Tested-by: Frank Rowand <frank.rowand@sonymobile.com>
Fixes: f7e54d7ad7 "msm_serial: Add support for poll_{get,put}_char()"
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The prefix suggests the number should be printed in hex, so use
the %x specifier to do that.
Found by using regex suggested by Joe Perches.
Signed-off-by: Hans Wennborg <hans@hanshq.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CLPS711X serial driver uses the system wide registers to control the
modem signals. Now gpio-syscon driver can be used for this purposes.
mctrl_gpio helpers allow us to create GPIO bindings for any of modem/tty
control signals that extends the functionality of the driver.
This patch makes such change.
This change does not break any current DT bindings, since DT support
for this platform is not introduced yet.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
printk replaced with corresponding dev_* .
fixed two broken user-visible strings used by the corresponding printk.
the null check for uport->dev and port->dev is removed as dev_* will check for
null while printing.
printing of dev_name(uport->dev) and dev_name(port->dev) also removed as those
are being printed by dev_* .
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make the of_device_id arrays const, as it is handled as const by all OF
functions.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fixed below checkpatch.pl warning:
WARNING: else is not generally useful after a break or return
Signed-off-by: Kiran Padwal <kiran.padwal@smartplayin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes below checkpatch.pl warning and it remove extra blank lines:
WARNING: Missing a blank line after declarations
Signed-off-by: Kiran Padwal <kiran.padwal@smartplayin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fixed below checkpatch.pl warning:
WARNING: braces {} are not necessary for any arm of this statement
Signed-off-by: Kiran Padwal <kiran.padwal@smartplayin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch lets you set the RS485 cappabilites of the device through
TIOCSRS485 and TIOCGRS485 as defined on Documentation/serial/serial-rs485.txt
In order to probe the device, the PNP id and the device id is used.
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch allow the users of the 8250 infrastructure to define a
handler for RS485 configration.
If no handler is defined the 8250 driver will work as usual.
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Acked-by: Alan Cox <alan@linux.intel.com>
--
v2:Change suggested by Alan "One Thousand Gnomes":
- Move rs485 structure further down on the uart_8250_port structure
drivers/tty/serial/8250/8250_core.c | 39 +++++++++++++++++++++++++++++++++++++
include/linux/serial_8250.h | 3 +++
2 files changed, 42 insertions(+)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add device ids for additional Neo cards. The ids come from the dgnc
driver.
Signed-off-by: Bill Pemberton <wfp5p@worldbroken.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add flags field to struct kernel_params, and add the first flag: unsafe
parameter. Modifying a kernel parameter with the unsafe flag set, either
via the kernel command line or sysfs, will issue a warning and taint the
kernel.
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Jon Mason <jon.mason@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
window:
Group changes to the device tree. In preparation for adding device tree
overlay support, OF_DYNAMIC is reworked so that a set of device tree
changes can be prepared and applied to the tree all at once. OF_RECONFIG
notifiers see the most significant change here so that users always get
a consistent view of the tree. Notifiers generation is moved from before
a change to after it, and notifiers for a group of changes are emitted
after the entire block of changes have been applied
Automatic console selection from DT. Console drivers can now use
of_console_check() to see if the device node is specified as a console
device. If so then it gets added as a preferred console. UART devices
get this support automatically when uart_add_one_port() is called.
DT unit tests no longer depend on pre-loaded data in the device tree.
Data is loaded dynamically at the start of unit tests, and then unloaded
again when the tests have completed.
Also contains a few bugfixes for reserved regions and early memory setup.
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Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux
Pull device tree updates from Grant Likely:
"The branch contains the following device tree changes the v3.17 merge
window:
Group changes to the device tree. In preparation for adding device
tree overlay support, OF_DYNAMIC is reworked so that a set of device
tree changes can be prepared and applied to the tree all at once.
OF_RECONFIG notifiers see the most significant change here so that
users always get a consistent view of the tree. Notifiers generation
is moved from before a change to after it, and notifiers for a group
of changes are emitted after the entire block of changes have been
applied
Automatic console selection from DT. Console drivers can now use
of_console_check() to see if the device node is specified as a console
device. If so then it gets added as a preferred console. UART
devices get this support automatically when uart_add_one_port() is
called.
DT unit tests no longer depend on pre-loaded data in the device tree.
Data is loaded dynamically at the start of unit tests, and then
unloaded again when the tests have completed.
Also contains a few bugfixes for reserved regions and early memory
setup"
* tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux: (21 commits)
of: Fixing OF Selftest build error
drivers: of: add automated assignment of reserved regions to client devices
of: Use proper types for checking memory overflow
of: typo fix in __of_prop_dup()
Adding selftest testdata dynamically into live tree
of: Add todo tasklist for Devicetree
of: Transactional DT support.
of: Reorder device tree changes and notifiers
of: Move dynamic node fixups out of powerpc and into common code
of: Make sure attached nodes don't carry along extra children
of: Make devicetree sysfs update functions consistent.
of: Create unlocked versions of node and property add/remove functions
OF: Utility helper functions for dynamic nodes
of: Move CONFIG_OF_DYNAMIC code into a separate file
of: rename of_aliases_mutex to just of_mutex
of/platform: Fix of_platform_device_destroy iteration of devices
of: Migrate of_find_node_by_name() users to for_each_node_by_name()
tty: Update hypervisor tty drivers to use core stdout parsing code.
arm/versatile: Add the uart as the stdout device.
of: Enable console on serial ports specified by /chosen/stdout-path
...
Merge more incoming from Andrew Morton:
"Two new syscalls:
memfd_create in "shm: add memfd_create() syscall"
kexec_file_load in "kexec: implementation of new syscall kexec_file_load"
And:
- Most (all?) of the rest of MM
- Lots of the usual misc bits
- fs/autofs4
- drivers/rtc
- fs/nilfs
- procfs
- fork.c, exec.c
- more in lib/
- rapidio
- Janitorial work in filesystems: fs/ufs, fs/reiserfs, fs/adfs,
fs/cramfs, fs/romfs, fs/qnx6.
- initrd/initramfs work
- "file sealing" and the memfd_create() syscall, in tmpfs
- add pci_zalloc_consistent, use it in lots of places
- MAINTAINERS maintenance
- kexec feature work"
* emailed patches from Andrew Morton <akpm@linux-foundation.org: (193 commits)
MAINTAINERS: update nomadik patterns
MAINTAINERS: update usb/gadget patterns
MAINTAINERS: update DMA BUFFER SHARING patterns
kexec: verify the signature of signed PE bzImage
kexec: support kexec/kdump on EFI systems
kexec: support for kexec on panic using new system call
kexec-bzImage64: support for loading bzImage using 64bit entry
kexec: load and relocate purgatory at kernel load time
purgatory: core purgatory functionality
purgatory/sha256: provide implementation of sha256 in purgaotory context
kexec: implementation of new syscall kexec_file_load
kexec: new syscall kexec_file_load() declaration
kexec: make kexec_segment user buffer pointer a union
resource: provide new functions to walk through resources
kexec: use common function for kimage_normal_alloc() and kimage_crash_alloc()
kexec: move segment verification code in a separate function
kexec: rename unusebale_pages to unusable_pages
kernel: build bin2c based on config option CONFIG_BUILD_BIN2C
bin2c: move bin2c in scripts/basic
shm: wait for pins to be released when sealing
...
This is the bulk of new SoC enablement and other platform changes for 3.17:
* Samsung S5PV210 has been converted to DT and multiplatform
* Clock drivers and bindings for some of the lower-end i.MX 1/2 platforms
* Kirkwood, one of the popular Marvell platforms, is folded into the
mvebu platform code, removing mach-kirkwood.
* Hwmod data for TI AM43xx and DRA7 platforms.
* More additions of Renesas shmobile platform support
* Removal of plat-samsung contents that can be removed with S5PV210 being
multiplatform/DT-enabled and the other two old platforms being removed.
New platforms (most with only basic support right now):
* Hisilicon X5HD2 settop box chipset is introduced
* Mediatek MT6589 (mobile chipset) is introduced
* Broadcom BCM7xxx settop box chipset is introduced
+ as usual a lot other pieces all over the platform code.
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Merge tag 'soc-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC platform changes from Olof Johansson:
"This is the bulk of new SoC enablement and other platform changes for
3.17:
- Samsung S5PV210 has been converted to DT and multiplatform
- Clock drivers and bindings for some of the lower-end i.MX 1/2
platforms
- Kirkwood, one of the popular Marvell platforms, is folded into the
mvebu platform code, removing mach-kirkwood
- Hwmod data for TI AM43xx and DRA7 platforms
- More additions of Renesas shmobile platform support
- Removal of plat-samsung contents that can be removed with S5PV210
being multiplatform/DT-enabled and the other two old platforms
being removed
New platforms (most with only basic support right now):
- Hisilicon X5HD2 settop box chipset is introduced
- Mediatek MT6589 (mobile chipset) is introduced
- Broadcom BCM7xxx settop box chipset is introduced
+ as usual a lot other pieces all over the platform code"
* tag 'soc-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (240 commits)
ARM: hisi: remove smp from machine descriptor
power: reset: move hisilicon reboot code
ARM: dts: Add hix5hd2-dkb dts file.
ARM: debug: Rename Hi3716 to HIX5HD2
ARM: hisi: enable hix5hd2 SoC
ARM: hisi: add ARCH_HISI
MAINTAINERS: add entry for Broadcom ARM STB architecture
ARM: brcmstb: select GISB arbiter and interrupt drivers
ARM: brcmstb: add infrastructure for ARM-based Broadcom STB SoCs
ARM: configs: enable SMP in bcm_defconfig
ARM: add SMP support for Broadcom mobile SoCs
Documentation: arm: misc updates to Marvell EBU SoC status
Documentation: arm: add URLs to public datasheets for the Marvell Armada XP SoC
ARM: mvebu: fix build without platforms selected
ARM: mvebu: add cpuidle support for Armada 38x
ARM: mvebu: add cpuidle support for Armada 370
cpuidle: mvebu: add Armada 38x support
cpuidle: mvebu: add Armada 370 support
cpuidle: mvebu: rename the driver from armada-370-xp to mvebu-v7
ARM: mvebu: export the SCU address
...
With memoryless node support being worked on, it's possible that for
optimizations that a node may not have a non-NULL zonelist. When
CONFIG_NUMA is enabled and node 0 is memoryless, this means the zonelist
for first_online_node may become NULL.
The oom killer requires a zonelist that includes all memory zones for
the sysrq trigger and pagefault out of memory handler.
Ensure that a non-NULL zonelist is always passed to the oom killer.
[akpm@linux-foundation.org: fix non-numa build]
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull sparc updates from David Miller:
1) Add sparc RAM output to /proc/iomem, from Bob Picco.
2) Allow seeks on /dev/mdesc, from Khalid Aziz.
3) Cleanup sparc64 I/O accessors, from Sam Ravnborg.
4) If update_mmu_cache{,_pmd}() is called with an not-valid mapping, do
not insert it into the TLB miss hash tables otherwise we'll
livelock. Based upon work by Christopher Alexander Tobias Schulze.
5) Fix BREAK detection in sunsab driver when no actual characters are
pending, from Christopher Alexander Tobias Schulze.
6) Because we have modules --> openfirmware --> vmalloc ordering of
virtual memory, the lazy VMAP TLB flusher can cons up an invocation
of flush_tlb_kernel_range() that covers the openfirmware address
range. Unfortunately this will flush out the firmware's locked TLB
mapping which causes all kinds of trouble. Just split up the flush
request if this happens, but in the long term the lazy VMAP flusher
should probably be made a little bit smarter.
Based upon work by Christopher Alexander Tobias Schulze.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next:
sparc64: Fix up merge thinko.
sparc: Add "install" target
arch/sparc/math-emu/math_32.c: drop stray break operator
sparc64: ldc_connect() should not return EINVAL when handshake is in progress.
sparc64: Guard against flushing openfirmware mappings.
sunsab: Fix detection of BREAK on sunsab serial console
bbc-i2c: Fix BBC I2C envctrl on SunBlade 2000
sparc64: Do not insert non-valid PTEs into the TSB hash table.
sparc64: avoid code duplication in io_64.h
sparc64: reorder functions in io_64.h
sparc64: drop unused SLOW_DOWN_IO definitions
sparc64: remove macro indirection in io_64.h
sparc64: update IO access functions in PeeCeeI
sparcspkr: use sbus_*() primitives for IO
sparc: Add support for seek and shorter read to /dev/mdesc
sparc: use %s for unaligned panic
drivers/sbus/char: Micro-optimization in display7seg.c
display7seg: Introduce the use of the managed version of kzalloc
sparc64 - add mem to iomem resource
Pull networking updates from David Miller:
"Highlights:
1) Steady transitioning of the BPF instructure to a generic spot so
all kernel subsystems can make use of it, from Alexei Starovoitov.
2) SFC driver supports busy polling, from Alexandre Rames.
3) Take advantage of hash table in UDP multicast delivery, from David
Held.
4) Lighten locking, in particular by getting rid of the LRU lists, in
inet frag handling. From Florian Westphal.
5) Add support for various RFC6458 control messages in SCTP, from
Geir Ola Vaagland.
6) Allow to filter bridge forwarding database dumps by device, from
Jamal Hadi Salim.
7) virtio-net also now supports busy polling, from Jason Wang.
8) Some low level optimization tweaks in pktgen from Jesper Dangaard
Brouer.
9) Add support for ipv6 address generation modes, so that userland
can have some input into the process. From Jiri Pirko.
10) Consolidate common TCP connection request code in ipv4 and ipv6,
from Octavian Purdila.
11) New ARP packet logger in netfilter, from Pablo Neira Ayuso.
12) Generic resizable RCU hash table, with intial users in netlink and
nftables. From Thomas Graf.
13) Maintain a name assignment type so that userspace can see where a
network device name came from (enumerated by kernel, assigned
explicitly by userspace, etc.) From Tom Gundersen.
14) Automatic flow label generation on transmit in ipv6, from Tom
Herbert.
15) New packet timestamping facilities from Willem de Bruijn, meant to
assist in measuring latencies going into/out-of the packet
scheduler, latency from TCP data transmission to ACK, etc"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1536 commits)
cxgb4 : Disable recursive mailbox commands when enabling vi
net: reduce USB network driver config options.
tg3: Modify tg3_tso_bug() to handle multiple TX rings
amd-xgbe: Perform phy connect/disconnect at dev open/stop
amd-xgbe: Use dma_set_mask_and_coherent to set DMA mask
net: sun4i-emac: fix memory leak on bad packet
sctp: fix possible seqlock seadlock in sctp_packet_transmit()
Revert "net: phy: Set the driver when registering an MDIO bus device"
cxgb4vf: Turn off SGE RX/TX Callback Timers and interrupts in PCI shutdown routine
team: Simplify return path of team_newlink
bridge: Update outdated comment on promiscuous mode
net-timestamp: ACK timestamp for bytestreams
net-timestamp: TCP timestamping
net-timestamp: SCHED timestamp on entering packet scheduler
net-timestamp: add key to disambiguate concurrent datagrams
net-timestamp: move timestamp flags out of sk_flags
net-timestamp: extend SCM_TIMESTAMPING ancillary data struct
cxgb4i : Move stray CPL definitions to cxgb4 driver
tcp: reduce spurious retransmits due to transient SACK reneging
qlcnic: Initialize dcbnl_ops before register_netdev
...
Fix detection of BREAK on sunsab serial console: BREAK detection was only
performed when there were also serial characters received simultaneously.
To handle all BREAKs correctly, the check for BREAK and the corresponding
call to uart_handle_break() must also be done if count == 0, therefore
duplicate this code fragment and pull it out of the loop over the received
characters.
Patch applies to 3.16-rc6.
Signed-off-by: Christopher Alexander Tobias Schulze <cat.schulze@alice-dsl.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
If gsmld_attach_gsm fails, the gsm is not used anymore.
tty core will not call gsmld_close to do the cleanup work.
tty core just restore to the tty old ldisc.
That always causes memory leak.
Signed-off-by: xinhui.pan <xinhuiX.pan@intel.com>
Reported-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The DMA is a function 0 of the multifunction device where SPI host is attached.
Thus, we may avoid to hardcode PCI slot number.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Just a simple cleanup of init_timer with setting the fields manually.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The s->clk never gets setup in sc16is7xx_probe() and instead was using a
local clk variable, but then testing the uninitialized s->clk during
teardown
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jon Ringle <jringle@gridpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The 8250_dw driver fails to probe if the specified clock isn't
registered at probe time. Even if a clock frequency is given,
the required clock might be gated because it wasn't properly
enabled.
This happened to me when the device is registered through DT,
and the clock was part of an MFD, the PRCM found on A31 and A23
SoCs. Unlike core clocks that are registered with OF_CLK_DECLARE,
which happen almost immediately after the kernel starts, the
clocks are registered as sub-devices of the PRCM MFD platform
device. Even though devices are registered in the order they are
found in the DT, the drivers are registered in a different,
arbitrary order. It is possible that the 8250_dw driver is
registered, and thus associated with the device and probed, before
the clock driver is registered and probed.
8250_dw then reports unable to get the clock, and fails. Without
a working console, the kernel panics.
This patch adds support for deferred probe handling for the clock
and reset controller. It also fixes the cleanup path if
serial8250_register_8250_port fails.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Allwinner A31 and A23 SoCs have a reset controller
maintaining the UART in reset by default.
This patch adds optional reset support to the driver.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the current calculation, if the required baud rate is above 262143,
we get an overflow.
This patch uses a 64bits variable to do the maths.
Also, we remove the '+1' to avoid a divide by zero if the input clock
rate is something unexpected.
Indeed, if the input clock rate is zero, it is preferable to be notified,
since the UART won't work anyway.
Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In order to prevent an asc instance to be used as early console, BUG_ON is
used on either mapbase or membase being NULL.
Problem is that this condition is also true when we set console to be a ttyASx
different to the first asc instance being probed.
Instead of calling BUG_ON, it now returns -ENXIO when either mapbase or
membase is NULL.
Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make of_device_id array const, because all OF functions handle it as const.
Signed-off-by: Kiran Padwal <kiran.padwal@smartplayin.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gsm->num is the index of gsm_mux[], it's invalid before calling gsm_activate_mux.
Signed-off-by: xinhui.pan <xinhuiX.pan@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Current code allocates too much data for tty_groups member of uart_port struct,
so fix it.
Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 3d1c90d48c ("serial: altera_jtaguart: Adpot
uart_console_write()") introduced the usage of uart_console_write() but
didn't change the signature of altera_jtaguart_console_putc() to take a
pointer to struct uart_port instead of struct console, breaking the
driver's console support and leading to the following warning:
> drivers/tty/serial/altera_jtaguart.c: In function 'altera_jtaguart_console_write':
> >> drivers/tty/serial/altera_jtaguart.c:350:2: warning: passing argument 4 of 'uart_console_write' from incompatible pointer type [enabled by default]
> uart_console_write(port, s, count, altera_jtaguart_console_putc);
> ^
> In file included from drivers/tty/serial/altera_jtaguart.c:25:0:
> include/linux/serial_core.h:317:6: note: expected 'void (*)(struct uart_port *, int)' but argument is of type 'void (*)(struct console *, int)'
> void uart_console_write(struct uart_port *port, const char *s,
Fix this by adjusting the signature of altera_jtaguart_console_putc()
accordingly.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All Samsung platforms are now using the Common Clock Framework and the
legacy clock code is being removed, so remove related dead code from
samsung-serial driver as well.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Add tunable RX interrupt trigger I/F of FIFO buffers.
Serial devices are used as not only message communication devices but control
or sending communication devices. For the latter uses, normally small data
will be exchanged, so user applications want to receive data unit as soon as
possible for real-time tendency. If we have a sensor which sends a 1 byte data
each time and must control a device based on the sensor feedback, the RX
interrupt should be triggered for each data.
According to HW specification of serial UART devices, RX interrupt trigger
can be changed, but the trigger is hard-coded. For example, RX interrupt trigger
in 16550A can be set to 1, 4, 8, or 14 bytes for HW, but current driver sets
the trigger to only 8bytes.
This patch makes some devices change RX interrupt trigger from userland.
<How to use>
- Read current setting
# cat /sys/class/tty/ttyS0/rx_trig_bytes
8
- Write user setting
# echo 1 > /sys/class/tty/ttyS0/rx_trig_bytes
# cat /sys/class/tty/ttyS0/rx_trig_bytes
1
<Support uart devices>
- 16550A and Tegra (1, 4, 8, or 14 bytes)
- 16650V2 (8, 16, 24, or 28 bytes)
- 16654 (8, 16, 56, or 60 bytes)
- 16750 (1, 16, 32, or 56 bytes)
<Change log>
Changes in V9:
- Use attr_group instead of dev_spec_attr_group of uart_port structure
Changes in V8:
- Divide this patch from V7's patch based on Greg's comment
Changes in V7:
- Add Documentation
- Change I/F name from rx_int_trig to rx_trig_bytes because the name
rx_int_trig is hard to understand how users specify the value
Changes in V6:
- Move FCR_RX_TRIG_* definition in 8250.h to include/uapi/linux/serial_reg.h,
rename those to UART_FCR_R_TRIG_*, and use UART_FCR_TRIGGER_MASK to
UART_FCR_R_TRIG_BITS()
- Change following function names:
convert_fcr2val() => fcr_get_rxtrig_bytes()
convert_val2rxtrig() => bytes_to_fcr_rxtrig()
- Fix typo in serial8250_do_set_termios()
- Delete the verbose error message pr_info() in bytes_to_fcr_rxtrig()
- Rename *rx_int_trig/rx_trig* to *rxtrig* for several functions or variables
(but UI remains rx_int_trig)
- Change the meaningless variable name 'val' to 'bytes' following functions:
fcr_get_rxtrig_bytes(), bytes_to_fcr_rxtrig(), do_set_rxtrig(),
do_serial8250_set_rxtrig(), and serial8250_set_attr_rxtrig()
- Use up->fcr in order to get rxtrig_bytes instead of rx_trig_raw in
fcr_get_rxtrig_bytes()
- Use conf_type->rxtrig_bytes[0] instead of switch statement for support check
in register_dev_spec_attr_grp()
- Delete the checking whether a user changed FCR or not when minimum buffer
is needed in serial8250_do_set_termios()
Changes in V5.1:
- Fix FCR_RX_TRIG_MAX_STATE definition
Changes in V5:
- Support Tegra, 16650V2, 16654, and 16750
- Store default FCR value to up->fcr when the port is first created
- Add rx_trig_byte[] in uart_config[] for each device and use rx_trig_byte[]
in convert_fcr2val() and convert_val2rxtrig()
Changes in V4:
- Introduce fifo_bug flag in uart_8250_port structure
This is enabled only when parity is enabled and UART_BUG_PARITY is enabled
for up->bugs. If this flag is enabled, user cannot set RX trigger.
- Return -EOPNOTSUPP when it does not support device at convert_fcr2val() and
at convert_val2rxtrig()
- Set the nearest lower RX trigger when users input a meaningless value at
convert_val2rxtrig()
- Check whether p->fcr is existing at serial8250_clear_and_reinit_fifos()
- Set fcr = up->fcr in the begging of serial8250_do_set_termios()
Changes in V3:
- Change I/F from ioctl(2) to sysfs(rx_int_trig)
Changed in V2:
- Use _IOW for TIOCSFIFORTRIG definition
- Pass the interrupt trigger value itself
Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some serial drivers (like 8250), want to add sysfs files. We need to do
so in a race-free way, so allow any port to be able to specify an
attribute group that should be added at device creation time.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
At present it is not possible to boot with the ttyNMI0 console treating
character input normally, instead character input triggers a prompt
telling the user how to trigger the knock detector and enter the
debugger. To use the console normally requires that kdb be entered and
the nmi_console command be used to enable the console (or if only kgdb
is present then gdb must directly manipulate the value of
kgdb_nmi_tty_enabled).
This patch automates the management of kgdb_nmi_tty_enabled by keeping
track of the number of file handles that are open for reading and using
that to determine how to tty should operate.
The approach means that:
1. Behaviour before init starts is unchanged.
2. If the userspace runs a getty or some other interactive process on
/dev/console (or explicitly on /dev/ttyNMI0) the tty will treat
character input like any other tty.
3. If the userspace doesn't use /dev/console or if it uses /dev/console
only to log messages (O_WRONLY) then the user prompt is retained.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: kgdb-bugreport@lists.sourceforge.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Follow commit 2970b7f5ea ("serial: altera: Adopt
uart_console_write()") and don't open code the LF to LFCR conversion in
altera_jtaguart either. Use uart_console_write() instead.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The of_node is derived from pdev for every usage, define a
device_node variable instead.
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The cases should comes before default in a switch.
Even if we want the case and default to share same code.
Its good to define the case first followed by default.
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
UART modules on some SoCs only differ in the fifosize of each
UART channel. Its useless to duplicate the drv_data structure
or create a compatible name for such a change.
We can get fifosize via the device tree nodes (not mandating it).
Also updates the documentation.
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It helps to cast struct uart_port to struct uart_8250_port at runtime.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This add the 32-bit register version LPUART support with big-endian
byte order.
Signed-off-by: Jingchang Lu <jingchang.lu@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the error of the same bit rate is detected, we will need to select
the recive margin is large. Current code holds the minimum error, it does
not have to check the recive margin. This adds this calculation.
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If bit-rate calculation result of HSCIF is expect 255 from 0,
driver does not calculate error bit. However, we need to round
the value to calculate error bit in the case of negative value.
This rounds the value of bit-rate using clamp(), and bit-rate is the
case of negative value, it enables the calculation of the error bit.
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the decimal point is discarded calculation of BRR.
Therefore, it can not calculate a value close to the correct value.
This patch fixes this problem by using DIV_ROUND_CLOSEST.
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In 2c964a2f "drivers: tty: Merge alloc_tty_struct and
initialize_tty_struct", I messed up the refactorization of
pty_common_install, causing use-after-free and NULL pointer derefs on
various error paths. This should fix it.
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The two functions alloc_tty_struct and initialize_tty_struct are
always called together. Merge them into alloc_tty_struct, updating its
prototype and the only two callers of these functions.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 16052827d9 ("dmaengine/dma_slave:
introduce inline wrappers") changed the code to use the new API, but forgot
to update an error message.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: linux-serial@vger.kernel.org
--
v2:
- New
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| drivers/tty/serial/arc_uart.c:516:2: warning: (near initialization for 'arc_serial_pops.poll_put_char') [enabled by default]
This partially undoes "serial/arc: use uart_console_write() helper" by
restoring the prototpye of poll helper and use a different one in
uart_console_write()
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This driver does not currently use uart_console_write() and instead
provides is own LF to LFCR conversion in it's console_write() method.
We should use the library function instead.
Cmopile tested only (with ARCH=arm).
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Cc: nios2-dev@lists.rocketboards.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Olof Johansson pointed out that usually the company name is picked as
namespace prefix to specific properties. So expect "energymicro,location"
but fall back to the previously introduced name "efm32,location".
Cc: Olof Johansson <olof@lixom.net>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix breakage introduced by
commit c557d392fb,
'serial: Test for no tx data on tx restart'.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace open-coded test for empty tx ring buffer with equivalent
helper function, uart_circ_empty(). No functional change.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 717f3bbab3,
'serial_core: Fix conditional start_tx on ring buffer not empty'
exposes an incorrect assumption in several drivers' start_tx methods;
the tx ring buffer can, in fact, be empty when restarting tx while
performing flow control.
Affected drivers:
sunsab.c
ip22zilog.c
pmac_zilog.c
sunzilog.c
m32r_sio.c
imx.c
Other in-tree serial drivers either are not affected or already
test for empty tx ring buffer before transmitting.
Test for empty tx ring buffer in start_tx() method, after transmitting
x_char (if applicable).
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Seth Bollinger <sethb@digi.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Cc: stable <stable@vger.kernel.org> # 3.15
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To support big-endian CPUs use the string versions of the io
read/write macros on the TX/RX fifos and the non-raw variants of
the readl/writel macros throughout. This way we don't byteswap
the characters coming from the fifos but we properly deal with
the little-endian nature of the serial hardware while controlling
it.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The TXX9_SIFCR_TDIL_MASK define is cut and pasted twice so we can delete
the second instance.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
blackfin uart port drivers mistakenly set the struct uart_port
flags bit UPF_BUG_THRE (which only has meaning to the 8250 core)
while trying to set ASYNC_CTS_FLOW.
Uart port drivers can override termios settings based on actual
hardware support in their .set_termios method; the serial core
sets the appropriate port flags based on the overrides.
Overriding only the initial termios settings is accomplished
by only perform those overrides if the old termios parameter is
NULL.
CC: Sonic Zhang <sonic.zhang@analog.com>
CC: adi-buildroot-devel@lists.sourceforge.net
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Uart port drivers may reconfigure termios settings based on available
hardware support; set/clear ASYNC_CTS_FLOW and ASYNC_CHECK_CD _after_
calling the port driver's .set_termios method.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since at least before 2.6.30, it has not been possible to observe
a hung up file pointer in a tty driver's open() method unless/until
the driver open() releases the tty_lock() (eg., before blocking).
This is because tty_open() adds the file pointer while holding
the tty_lock() _and_ doesn't release the lock until after calling
the tty driver's open() method. [ Before tty_lock(), this was
lock_kernel(). ]
Since __tty_hangup() first waits on the tty_lock() before
enumerating and hanging up the open file pointers, either
__tty_hangup() will wait for the tty_lock() or tty_open() will
not yet have added the file pointer. For example,
CPU 0 | CPU 1
|
tty_open | __tty_hangup
.. | ..
tty_lock | ..
tty_reopen | tty_lock / blocks
.. |
tty_add_file(tty, filp) |
.. |
tty->ops->open(tty, filp) |
tty_port_open |
tty_port_block_til_ready |
.. |
while (1) |
.. |
tty_unlock | / unblocks
schedule | for each filp on tty->tty_files
| f_ops = tty_hung_up_fops;
| ..
| tty_unlock
tty_lock |
.. |
tty_unlock |
Note that since tty_port_block_til_ready() and similar drop
the tty_lock while blocking, when woken, the file pointer
must then be tested for having been hung up.
Also, fix bit-rotted drivers that used extra_count to track the
port->count bump.
CC: Mikael Starvik <starvik@axis.com>
CC: Samuel Ortiz <samuel@sortiz.org>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix ASYNC_* constant usage that should be the corresponding UPF_*
constant.
CC: Grant Likely <grant.likely@linaro.org>
CC: Rob Herring <robh+dt@kernel.org>
CC: devicetree@vger.kernel.org
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty->closing cannot be set on ipw_open() because the ipwireless tty
driver does not call any functions that set tty->closing.
CC: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty->closing informs the line discipline that the hardware will
be shutting down imminently, and to disable further input other
than soft flow control (but to still allow additional output).
However, the tty lock is the necessary lock for preventing
concurrent changes to tty->closing. As shown by the call-tree
audit [1] of functions that modify tty->closing, the tty lock
is already held for those functions.
[1]
Call-tree audit of functions that modify tty->closing
* does not include call tree to tty_port_close(), tty_port_close_start(),
or tty_port_close_end() which is already documented in
'tty: Document locking for tty_port_close{,start,end}' that shows
callers to those 3 functions hold the tty lock
tty_release()
tty->ops->close() --+
|
__tty_hangup() |
tty->ops->close() --+
|
mp_close():drivers/staging/sb105x/sb_pci_mp.c
dngc_tty_close():drivers/staging/dgnc/dgnc_tty.c
dgap_tty_close():drivers/staging/dgap/dgap_tty.c
dgrp_tty_close():drivers/staging/dgrp/dgrp_tty.c
rp_close():drivers/tty/rocket.c
hvsi_close():drivers/tty/hvc/hvsi.c
rs_close():drivers/tty/serial/68328serial.c
rs_close():drivers/tty/serial/crisv10.c
uart_close():drivers/tty/serial/serial_core.c
isdn_tty_close():drivers/isdn/i4l/isdn_tty.c
tty3215_close():drivers/s390/char/con3215.c
tty_open()
tty_ldisc_setup() ----+
|
__tty_hangup() |
tty_ldisc_hangup() ---+
|
tty_set_ldisc() --------+
tty_ldisc_restore() --+
|
+- tty_ldisc_open()
ld->ops->open() --+
|
+- n_tty_open()
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty lock is held when the tty driver's hangup() method is called
(from the lone call-site, __tty_hangup()). The call-tree audit [1]
of tty_port_hangup() is a closed graph of the callers of
tty_port_hangup(); ie., all callers originate only from __tty_hangup().
Of these callers, none drop the tty lock prior to calling
tty_port_hangup().
[1]
Call-tree audit of tty_port_hangup()
__tty_hangup()
tty->ops->hangup() --+
|
rs_hangup():arch/ia64/hp/sim/simserial.c
line_hangup():arch/um/drivers/line.c
gdm_tty_hangup():drivers/staging/gdm724x/gdm_tty.c
fwtty_hangup():drivers/staging/fwserial/fwserial.c
acm_tty_hangup():drivers/usb/class/cdc-acm.c
serial_hangup():drivers/usb/serial/usb-serial.c
ipoctal_hangup():drivers/ipack/devices/ipoctal.c
cy_hangup():drivers/tty/cyclades.c
isicom_hangup():drivers/tty/isicom.c
rp_hangup():drivers/tty/rocket.c
dashtty_hangup():drivers/tty/metag_da.c
moxa_hangup():drivers/tty/moxa.c
gsmtty_hangup():drivers/tty/n_gsm.c
goldfish_tty_hangup():drivers/tty/goldfish.c
ehv_bc_tty_hangup():drivers/tty/ehv_bytechan.c
mxser_hangup():drivers/tty/mxser.c
kgdb_nmi_tty_hangup():drivers/tty/serial/kgdb_nmi.c
ifx_spi_hangup():drivers/tty/serial/ifx6x60.c
ntty_hangup():drivers/tty/nozomi.c
capinc_tty_hangup():drivers/isdn/capi/capi.c
mgslpc_hangup():drivers/char/pcmcia/synclink_cs.c
sdio_uart_hangup():drivers/mmc/card/sdio_uart.c
rfcomm_tty_hangup():net/bluetooth/rfcomm/tty.c
|
+- tty_port_hangup()
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty lock is held when the tty driver's open() method is called
(from tty_open()). The call-tree audit [1] of tty_port_block_til_ready()
is a closed graph of the callers of tty_port_block_til_ready();
ie., all callers originate only from tty_open().
Of these callers, none drop the tty lock.
Also, document tty_port_block_til_ready() may drop and reacquire
the tty lock when blocking, which means the tty or tty_port may have
changed state.
[1]
Call-tree audit of tty_port_block_til_ready()
* does not include call tree of tty_port_open() which is already
documented in 'tty: Document locking from tty_port_open()'
tty_open()
tty->ops->open() --+
|
cy_open():drivers/tty/cyclades.c
rp_open():drivers/tty/rocket.c
rs_open():drivers/tty/amiserial.c
moxa_open():drivers/tty/moxa.c
gsmtty_open():drivers/tty/n_gsm.c
rs_open():drivers/tty/serial/68328serial.c
uart_open():drivers/tty/serial/serial_core.c
isdn_tty_open():drivers/isdn/i4l/isdn_tty.c
mgslpc_open():drivers/char/pcmcia/synclink_cs.c
|
+- tty_port_block_til_ready()
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty lock is held when the tty driver's open method is called
(from the lone call-site, tty_open()). The call-tree audit [1] of
tty_port_open() is a closed graph of the callers of tty_port_open();
ie., all callers originate from only tty_open().
Of these callers, none drop the tty lock.
Also, document that tty_port_block_til_ready() may drop and reacquire
the tty lock when blocking, which means the tty or tty_port may have
changed state.
[1]
Call-tree audit of tty_port_open()
tty_open()
tty->ops->open() --+
|
rs_open():arch/ia64/hp/sim/simserial.c
*line_open():arch/um/drivers/line.c
gdm_tty_open():drivers/staging/gdm724x/gdm_tty.c
fwtty_open():drivers/staging/fwserial/fwserial.c
acm_tty_open():drivers/usb/class/cdc-acm.c
serial_open():drivers/usb/serial/usb-serial.c
pti_tty_driver_open():drivers/misc/pti.c
ipoctal_open():drivers/ipack/devices/ipoctal.c
isicom_open():drivers/tty/isicom.c
dashtty_open():drivers/tty/metag_da.c
goldfish_tty_open():drivers/tty/goldfish.c
ehv_bc_tty_open():drivers/tty/ehv_bytechan.c
mxser_open():drivers/tty/mxser.c
kgdb_nmi_tty_open():drivers/tty/serial/kgdb_nmi.c
ifx_spi_open():drivers/tty/serial/ifx6x60.c
smd_tty_open():drivers/tty/serial/msm_smd_tty.c
ntty_open():drivers/tty/nozomi.c
capinc_tty_open():drivers/isdn/capi/capi.c
tpk_open():drivers/char/ttyprintk.c
sdio_uart_open():drivers/mmc/card/sdio_uart.c
rfcomm_tty_open():net/bluetooth/rfcomm/tty.c
|
+- tty_port_open()
* line_open() is the .open method for 2 um drivers
declared in ./arch/um/drivers/stdio_console.c and
in ./arch/um/drivers/ssl.c, and not called directly
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty lock is held when the tty driver's .close method is called
(from the two lone call-sites of tty_release() and __tty_hangup()).
The call-tree audit[1] of tty_port_close(), tty_port_close_start,
and tty_port_close_end() is a closed graph of the callers of these
3 functions; ie., all callers originate from only tty_release()
or __tty_hangup().
Of these callers, none drop the tty lock.
Also, document tty_port_close_start() may drop and reacquire the
tty lock in tty_wait_until_sent_from_close(), which means the tty
or tty_port may have changed state (but not reopened or hung up).
[1]
Call-tree audit of tty_port_close, tty_port_close_start, and tty_port_close_end()
tty_release()
tty->ops->close() --+
|
__tty_hangup() |
tty->ops->close() --+
|
+- rp_close():drivers/tty/rocket.c -------------------+
+- uart_close():drivers/tty/serial/serial_core.c -----+
| +- tty_port_close_start()
|
|
+- close():drivers/tty/synclinkmp.c ------------------+
+- rs_close():drivers/tty/amiserial.c ----------------+
+- gsmtty_close():drivers/tty/n_gsm.c ----------------+
+- mxser_close():drivers/tty/mxser.c -----------------+
+- close():drivers/tty/synclink_gt.c -----------------+
+- mgsl_close():drivers/tty/synclink.c ---------------+
+- isdn_tty_close():drivers/isdn/i4l/isdn_tty.c ------+
+- mgslpc_close():drivers/char/pcmcia/synclink_cs.c --+
+- ircomm_tty_close():net/irda/ircomm/ircomm_tty.c ---+
| |
rs_close():arch/ia64/hp/sim/simserial.c |
*line_close():arch/um/drivers/line.c |
gdm_tty_close():drivers/staging/gdm724x/gdm_tty.c
fwtty_close():drivers/staging/fwserial/fwserial.c
acm_tty_close():drivers/usb/class/cdc-acm.c
serial_close():drivers/usb/serial/usb-serial.c
pti_tty_driver_close():drivers/misc/pti.c
ipoctal_close():drivers/ipack/devices/ipoctal.c
cy_close():drivers/tty/cyclades.c
isicom_close():drivers/tty/isicom.c
dashtty_close():drivers/tty/metag_da.c
moxa_close():drivers/tty/moxa.c
goldfish_tty_close():drivers/tty/goldfish.c
ehv_bc_tty_close():drivers/tty/ehv_bytechan.c
kgdb_nmi_tty_close():drivers/tty/serial/kgdb_nmi.c
ifx_spi_close():drivers/tty/serial/ifx6x60.c
smd_tty_close():drivers/tty/serial/msm_smd_tty.c
ntty_close():drivers/tty/nozomi.c
capinc_tty_close():drivers/isdn/capi/capi.c
tpk_close():drivers/char/ttyprintk.c
sdio_uart_close():drivers/mmc/card/sdio_uart.c |
rfcomm_tty_close():net/bluetooth/rfcomm/tty.c |
| |
+- tty_port_close():drivers/tty/tty_port.c -----------+
|
+- tty_port_close_start()
+- tty_port_close_end()
* line_close() is the .close method for 2 um drivers,
declared in ./arch/um/drivers/stdio_console.c and
in ./arch/um/drivers/ssl.c, and not called directly
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The DMA burst size must match the transmit FIFO depth in order
to make sure all character are transmitted. This patch calculates
DMA burst size by using FIFO depth rather than use the hardcoded
16 bytes. This is required since some UARTs (e.g. UART2 on Vybrid)
have a FIFO depth of 8 bytes.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The DMA RX timeout calculation is done based on FIFO buffer size and
port timeout when setting up DMA. However, both variables are not
necessarily initialized at DMA initialization time, which can lead
to a division by zero.
Move the timeout calculation to set_termios where both variables
are initialized.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a tty is opened for the serial console, the termios c_cflag
settings are inherited from the console line settings.
However, if the tty is subsequently closed, the termios settings
are lost. This results in a garbled console if the console is later
suspended and resumed.
Preserve the termios c_cflag for the serial console when the tty
is shutdown; this reflects the most recent line settings.
Fixes: Bugzilla #69751, 'serial console does not wake from S3'
Reported-by: Valerio Vanni <valerio.vanni@inwind.it>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Rx dma descriptor allocated without the DMA_ACK flags so that
once after tarnsfer done or terminated, client can ack the descriptor
to free it for later use.
If the Rx DMA is terminated for some reason then rx-dma descriptor
is not getting acked which causes the memory leak and list of usage
desc to grow continuously.
Hence, acknowledge the rx-dma descriptor once transfer is terminated
to avoid memory leak and desc list to grow.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When channel is require to stop transmit then update the Tx circular
buffer only when DMA based transfer is in progress. If there is no
DMA based transfer then no need to update the Tx buffer.
Signed-off-by: Pradeep Goudagunta <pgoudagunta@nvidia.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Every uart driver that provides a console driver needs to
be built-in for the console code to work, we get a build
error for modular console drivers.
This changes the SERIAL_HS_LPC32XX_CONSOLE symbol to depend
on the SERIAL_HS_LPC32XX driver being built-in, just like
we do for all the other uart drivers.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When CONFIG_SERIAL_PXA_CONSOLE is disabled, the serial_pxa_get_poll_char
and serial_pxa_put_poll_char functions are not defined, and we can't
reference them.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This allows a param less earlycon to pick up the earlyconsole from
chosen/stdout-path
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With this change both earlyprintk and earlycon coexist
We switch over to latter in next patch
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The ARC UART MMIO helpers would take arc_uart_port and then reference
generic uart_port->membase member. So change them to difrectly refer to
uart_port and fix call sites accordingly.
This removes the need for to_arc_port() converion almost eveeywhere and
makes code a bit easier to read.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
First try to find the named clock variants then fall back to the already
existing handling of a nameless declared baudclk.
This also adds the missing documentation for this already existing variant.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The flags member has upf_t type and corresponding macros to define them. This
patch converts ASYNC_SKIP_TEST to UPF_SKIP_TEST in 8250_dw.c.
Otherwise we got a sparse warning:
drivers/tty/serial/8250/8250_dw.c:302:46: warning: restricted upf_t degrades to integer
drivers/tty/serial/8250/8250_dw.c:302:62: warning: restricted upf_t degrades to integer
drivers/tty/serial/8250/8250_dw.c:302:26: warning: incorrect type in assignment (different base types)
drivers/tty/serial/8250/8250_dw.c:302:26: expected restricted upf_t [usertype] flags
drivers/tty/serial/8250/8250_dw.c:302:26: got unsigned int
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This replaces the Baytrail specific custom set_termios hook
with a more generic one where the clock framework is used to
set the rate. The method also doesn't need to be limited to
just Baytrail, so it's used with all ACPI platforms.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When building multi_v7_defconfig with CONFIG_ARM_LPAE=y the following warning
is seen:
drivers/tty/serial/samsung.c: In function 's3c24xx_serial_init_port':
drivers/tty/serial/samsung.c:1229:2: warning: format '%x' expects argument of type 'unsigned int', but argument 2 has type 'resource_size_t' [-Wformat]
Use %pa to print 'resource_size_t' type to fix the warning.
Reported-by: Olof's autobuilder <build@lixom.net>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a risk that the variable will be used without being initialized.
This was largely found by using a static code analysis program called cppcheck.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
the current codes send 1 bytes, then after getting TX done interrupt,
send subsequent bytes. it causes redundant interrupts.
for example, if we have 3 bytes in TX buffer, the TX flow is:
1. send 1 byte
2. get TX down interrupt
3. send the left 2 bytes
4. get TX down interrupt
this patch moves to send more bytes and decrease interrupts, the new
flow is:
1. send 3 bytes
2. get TX down interrupt
Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Call uart_write_wakeup() after writing the hardware FIFO and updateing the FIFO
pointers.
This fixes high latency and jitter on PPP over Serial links.
Reported-by: Jun Shih <Jun.Shih@pason.com>
Tested-by: Jun Shih <Jun.Shih@pason.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@men.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch makes enable_ms() optional, so we can eliminate a lot of
empty enable_ms() implementations from driver code.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch removes s5p64x0 related serial because of removing
support for s5p64x0 SoCs.
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Current driver code relies on probe order of particular samsung-uart
instances, which makes it impossible to get proper initialization of
ports when not all ports are available on board, not even saying of
deterministic device naming.
This patch fixes this on DT-enabled systems by using DT aliases for
ports as instance ID, if specified, or falling back to legacy method
otherwise to provide backwards compatibility.
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Migrating to use devres managed APIs devm_kzalloc, devm_ioremap and
devm_clk_get.
Signed-off-by: Tushar Behera <tushar.b@samsung.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Matthias Brugger