Commit Graph

1896 Commits

Author SHA1 Message Date
Kumar Gala fe655de171 tty/serial: earlycon: Fix print for implied MMIO case
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>
2014-11-05 19:45:52 -08:00
Greg Kroah-Hartman 28e1445c65 Merge branch 'tty-linus' into 'tty-testing'
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>
2014-11-05 19:43:23 -08:00
Ricardo Ribalda Delgado c015b4ad2a serial/sc16is7xx: Remove obsolete #ifset TIOC[SG]RS485
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>
2014-11-05 19:29:05 -08:00
Ricardo Ribalda Delgado aad31088db serial/max310x: Remove obsolete #ifset TIOC[SG]RS485
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>
2014-11-05 19:29:05 -08:00
Ray Jui a8b26e1af9 serial: 8250_dw: Add DMA support for non-ACPI platforms
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>
2014-11-05 19:24:07 -08:00
Gregory Hermant 32304d7533 max310x: max3109_detect should use indirect addressing in SPI mode for REVID register
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>
2014-11-05 19:24:07 -08:00
Paul Bolle 510d483285 serial: samsung: Remove checks for CONFIG_SAMSUNG_CLOCK
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>
2014-11-05 19:22:09 -08:00
Fabian Frederick f9c1b28e89 tty: ar933x_uart: use container_of to resolve ar933x_uart_port from uart_port
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>
2014-11-05 19:20:53 -08:00
Fabian Frederick 6f414130e8 serial: use container_of to resolve uart_sunzilog_port from uart_port
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>
2014-11-05 19:20:53 -08:00
Fabian Frederick afc5438b4c serial: pnx8xxx: use container_of to resolve pnx8xxx_port from uart_port
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>
2014-11-05 19:20:53 -08:00
Fabian Frederick b70e5e9d71 serial: amba-pl010: use container_of to resolve uart_amba_port from uart_port
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>
2014-11-05 19:20:52 -08:00
Fabian Frederick 726657653f serial: sunsab: use container_of to resolve uart_sunsu_port from uart_port
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>
2014-11-05 19:20:52 -08:00
Fabian Frederick 9a6962c531 serial: sunsu: use container_of to resolve uart_sunsu_port from uart_port
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>
2014-11-05 19:20:52 -08:00
Fabian Frederick edb20c7aa5 tty: use container_of to resolve uart_pmac_port from uart_port
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>
2014-11-05 19:20:52 -08:00
Fabian Frederick a15ad34834 TTY: jsm: use container_of to resolve jsm_channel from uart_port
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>
2014-11-05 19:20:52 -08:00
Fabian Frederick e789d26887 serial: cpm_uart: use container_of to resolve uart_cpm_port from uart_port
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>
2014-11-05 19:20:52 -08:00
Fabian Frederick 22d4d44c4c serial: mpsc: use container_of to resolve mpsc_port_info from uart_port
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>
2014-11-05 19:20:52 -08:00
Fabian Frederick 2413b32062 serial: use container_of to resolve uart_ip22zilog_port from uart_port
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>
2014-11-05 19:20:52 -08:00
Fabian Frederick c9db776b57 serial: sa1100: use container_of to resolve sa1100_port from uart_port
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>
2014-11-05 19:20:52 -08:00
Fabian Frederick b6b30d67f3 serial: use container_of to resolve uart_sio_port from uart_port
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>
2014-11-05 19:20:52 -08:00
Sebastian Andrzej Siewior 0a0661ddb8 tty: serial: 8250: omap: add dma support
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>
2014-11-05 19:13:34 -08:00
Sebastian Andrzej Siewior 77285243a6 tty: serial: 8250: omap: add custom irq handling
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>
2014-11-05 19:13:34 -08:00
Sebastian Andrzej Siewior 0e31c8d173 tty: serial: 8250_omap: add custom DMA-RX callback
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>
2014-11-05 19:10:07 -08:00
Sebastian Andrzej Siewior 31a171328e tty: serial: 8250_omap: add custom DMA-TX callback
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>
2014-11-05 19:10:07 -08:00
Sebastian Andrzej Siewior f1a297bb04 tty: serial: 8250: allow to use custom DMA implementation
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>
2014-11-05 19:07:48 -08:00
Sebastian Andrzej Siewior 0fcb7901f9 tty: serial: 8250_dma: keep own book keeping about RX transfers
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>
2014-11-05 19:05:13 -08:00
Sebastian Andrzej Siewior b220282156 tty: serial: 8250_dma: handle error on TX submit
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>
2014-11-05 19:05:13 -08:00
Sebastian Andrzej Siewior 61929cf016 tty: serial: Add 8250-core based omap driver
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>
2014-11-05 19:05:13 -08:00
Sebastian Andrzej Siewior f31b5d27be tty: serial: 8250: make serial8250_console_setup() non _init
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>
2014-11-05 19:02:59 -08:00
Sebastian Andrzej Siewior 6a529abae8 tty: serial: 8250: Fix wording in runtime-PM comments
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>
2014-11-05 19:02:59 -08:00
Janusz Uzycki 914d3b17e9 serial: mxs-auart: add sysrq support
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>
2014-11-05 18:56:47 -08:00
Markus Pargmann d4ac0633ad tty: serial: omap: Remove probe error message
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>
2014-11-05 18:56:47 -08:00
Peter Hurley 91b32f5413 serial: core: Fix port count when uart_open() errors
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>
2014-11-05 18:53:55 -08:00
Peter Hurley 64dbee3105 serial: core: Remove extra locking in uart_write()
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>
2014-11-05 18:53:55 -08:00
Peter Hurley 2b702b9b68 serial: core: Colocate crucial structure linkage
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>
2014-11-05 18:53:55 -08:00
Peter Hurley 1f0afd1607 serial: core: Remove redundant timeout assignments
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>
2014-11-05 18:53:55 -08:00
Peter Hurley 74866e7593 serial: core: Unwrap >80 char line in uart_close()
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>
2014-11-05 18:53:55 -08:00
Peter Hurley 7c8ab967e3 serial: Fix locking for uart driver set_termios() method
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>
2014-11-05 18:53:54 -08:00
Peter Hurley 2e75891083 serial: core: Flush ldisc after dropping port mutex in uart_close()
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>
2014-11-05 18:53:54 -08:00
Peter Hurley 479e9b94fd serial: Refactor uart_flush_buffer() from uart_close()
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>
2014-11-05 18:53:54 -08:00
Mike Skoog 1bc8cde46a 8250_pci: Added driver for Endrun Technologies PTP PCIe card.
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>
2014-11-05 16:36:01 -08:00
Sudhir Sreedharan edf4edacb3 tty: serial: 8250_core: restore the LCR register in set_sleep
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>
2014-11-05 16:23:34 -08:00
Jingchang Lu 513e438581 serial: of-serial: fix up PM ops on no_console_suspend and port type
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>
2014-11-05 16:23:34 -08:00
Peter Hurley 91f189de46 serial: Fix sparse warnings in uart_throttle()/uart_unthrottle()
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>
2014-11-05 16:15:43 -08:00
Peter Hurley d4260b5169 serial: Fix upstat_t sparse warnings
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>
2014-11-05 16:15:43 -08:00
Peter Hurley 547039ec50 serial: Fix divide-by-zero fault in uart_get_divisor()
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>
2014-11-05 16:14:09 -08:00
Linus Torvalds 52d589a01d Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma
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
  ...
2014-10-18 18:11:04 -07:00
Vinod Koul 6b997bab20 serial: atmel: add missing dmaengine header
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>
2014-10-16 14:08:05 +05:30
Vinod Koul 2856fcdc1f Merge branch 'topic/dma_control_cleanup_acks' into for-linus 2014-10-15 21:38:49 +05:30
Vinod Koul 2bcd90d56c serial: sh-sci: use dmaengine_terminate_all() API
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>
2014-10-15 21:31:00 +05:30