Commit Graph

3211 Commits

Author SHA1 Message Date
Tony Lindgren 4e0f5cc650 serial: 8250_omap: Fix probe and remove for PM runtime
Otherwise the interconnect related code implementing PM runtime will
produce these errors on a failed probe:

omap_uart 48066000.serial: omap_device: omap_device_enable() called from invalid state 1
omap_uart 48066000.serial: use pm_runtime_put_sync_suspend() in driver?

Note that we now also need to check for priv in omap8250_runtime_suspend()
as it has not yet been registered if probe fails. And we need to use
pm_runtime_put_sync() to properly idle the device like we already do
in omap8250_remove().

Fixes: 61929cf016 ("tty: serial: Add 8250-core based omap driver")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 11:08:30 +01:00
Paul Gortmaker f99b63afb9 serial: hp300: mask the warning for people just doing build coverage
Currently this warning is triggered for allmodconfig on m68k.  It is
well intentioned, in that if you are building the driver but not
enabling one of the platforms where the hardware exists, you get a
warning.

The warning dates back to pre-git days, and now we have COMPILE_TEST
so we can use that to mask the warning for people who are obviously
just doing build coverage on tree wide changes.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-serial@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 11:08:30 +01:00
Yasir-Khan 5935a2b3a5 serial: xuartps: Enable uart loopback mode
This patch adds xilinx uart loopback support by modifying the
cdns_uart_set_mctrl function to handle the switch to loopback mode.
After this patch, the loopback mode can be enabled/disabled by
setting/clearing the TIOCM_LOOP modem bit via TIOCMBIS/TIOCMBIC
ioctls respectively.

Signed-off-by: Yasir-Khan <yasir_khan@mentor.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 11:08:30 +01:00
Vignesh R aa75941ca1 serial: 8250_omap: Remove rx_dma_broken flag
8250 UART DMA support was marked broken by default as it was not
possible to pause ongoing RX DMA transfer. Now that both SDMA and
EDMA can support pause operation for RX DMA transactions, don't set
rx_dma_broken to true by default. With this patch 8250_omap driver will
use DMA by default.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:44:37 +01:00
Vignesh R b6ffcf2108 serial: 8250_omap: Add OMAP_DMA_TX_KICK quirk for AM437x
UART uses as EDMA as dma engine on AM437x SoC and therefore, requires
OMAP_DMA_TX_KICK quirk just like AM33xx. So, enable OMAP_DMA_TX_KICK
quirk for AM437x platform as well. While at that, drop use of
of_machine_is_compatible() and instead pass quirks via device data.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:44:37 +01:00
Vignesh R 75f54acc08 serial: 8250_omap: pause DMA only if DMA transfer in progress
It is possible that DMA transfer is already complete but, completion
handler is yet to be called, when dmaengine_pause() is called in case of
error condition(like break/rx timeout). This leads to dmaengine_pause()
API to return EINVAL (as descriptor is already NULL) causing
rx_dma_broken flag to be set and effectively disabling RX DMA.
Fix this by calling dmaengine_pause() only when transfer is in progress.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:44:37 +01:00
Martin Blumenstingl 8c9faa556a tty: serial: meson: allow baud-rates higher than 115200
The vendor driver allows setting baud-rates higher than 115200 baud.
There is a check in the vendor driver which prevents using more than
115200 baud during startup, however it does not have such a check in
.set_termios.
Higher baud-rates are often used by the bluetooth modules embedded into
the SDIO wifi chips (Amlogic devices use brcmfmac based wifi chips quite
often, 2000000 baud seems to be a common value for the UART baud-rate in
Amlogic's "libbt").

I have tested this on a Meson GXL device with uart_A (to which the
bluetooth module is connected, where initialization times out with
115200 baud) and uart_AO (which I manually set to 2000000 baud  and then
connected with my USB UART adapter to that).

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:38:57 +01:00
Arvind Yadav 2cc32b18d1 tty: serial: 8250: 8250_gsc:- Handle return NULL error from ioremap_nocache
Here, If ioremap_nocache will fail. It will return NULL.
Kernel can run into a NULL-pointer dereference.
This error check will avoid NULL pointer dereference.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:20:23 +01:00
Lokesh Vutla 28ec9570a2 serial: omap: Add omapserial earlycon
Add DT earlycon for omap_serial driver. This boot console is included
with CONFIG_SERIAL_EARLYCON=y, CONFIG_OF=y, CONFIG_SERIAL_OMAP=y, and
CONFIG_OF_EARLY_FLATTREE=y.

This boot console is enabled with the command line option "earlycon"
(without "=<name>...") when the DT 'stdout-path' property matches a
compatible uart.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:20:23 +01:00
Alexander Sverdlin 7951ffc9ea serial: pl011: Mark console as CON_ANYTIME
Exactly as in a80c49db ("serial8250: Mark console as CON_ANYTIME"),
to enable printk() during CPU hot-plugging.

Actually most of the serial console drivers do not use per-cpu resources
and can be marked as CON_ANYTIME.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:20:23 +01:00
Bhumika Goyal 1ea146a7dc tty: serial: constify dev_pm_ops structures
Declare dev_pm_ops structures as const as they are only stored in the pm
field of a device_driver structure. This field is of type const, so
dev_pm_ops structures having similar properties can be declared const
too.

Size details after cross compiling the .o file for blackfin architecture.

File size before:
  text	   data	    bss	    dec	    hex	filename
   3572	    320	     16	   3908	    f44 tty/serial/bfin_sport_uart.o

File size after:
   text	   data	    bss	    dec	    hex	filename
   3664	    228	     16	   3908	    f44 tty/serial/bfin_sport_uart.o

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:20:23 +01:00
Andy Shevchenko 216e234d66 serial: 8250_mid: set PCI master only for DMA capable device
There is no need to set PCI bus mastering when device is not doing any DMA. It
includes MSI type of interrupts. Currently only UART on Denverton, which is DMA
capable, might have MSI enabled.

Taking above into account enable bus mastering for Denverton case only.

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:20:23 +01:00
Andy Shevchenko 6d59225f2d serial: 8250_mid: enable MSI on Denverton
Enable MSI type of interrupt if PCI BIOS supports it.

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:20:23 +01:00
Andy Shevchenko 4831e0d905 serial: 8250_mid: handle interrupt correctly in DMA case
Starting from Tangier B0 and continuing on Anniedale the HSU DMA interrupt
line is actually shared with UART. Handling them independently is racy and
quite often comes with the following traceback.

 irq 54: nobody cared (try booting with the "irqpoll" option)
 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.0-rc6-edison64-86244934+ #1
 Hardware name: Intel Corporation Merrifield/BODEGA BAY, BIOS 542 2015.01.21:18.19.48
  ffff88003f203eb0 ffffffff8130e718 ffff880032627000 ffff88003262709c
  ffff88003f203ed8 ffffffff810a3960 ffff880032627000 0000000000000000
  ffff880032627000 ffff88003f203f10 ffffffff810a3cc7 ffff880032627000
 Call Trace:
  <IRQ>
  [<ffffffff8130e718>] dump_stack+0x4d/0x65
  [<ffffffff810a3960>] __report_bad_irq+0x30/0xc0
  [<ffffffff810a3cc7>] note_interrupt+0x227/0x270
  [<ffffffff810a1380>] handle_irq_event_percpu+0x40/0x50
  [<ffffffff810a13b7>] handle_irq_event+0x27/0x50
  [<ffffffff810a42d5>] handle_fasteoi_irq+0x85/0x150
  [<ffffffff8101d7fe>] handle_irq+0x6e/0x120
  [<ffffffff8105b8bc>] ? _local_bh_enable+0x1c/0x50
  [<ffffffff8101d0d6>] do_IRQ+0x46/0xd0
  [<ffffffff818cef3f>] common_interrupt+0x7f/0x7f
  <EOI>
  [<ffffffff818cdead>] ? mwait_idle+0x7d/0x140
  [<ffffffff81024c9a>] arch_cpu_idle+0xa/0x10
  [<ffffffff818ce150>] default_idle_call+0x20/0x30
  [<ffffffff810908fd>] cpu_startup_entry+0x16d/0x1d0
  [<ffffffff818c882d>] rest_init+0x6d/0x70
  [<ffffffff81f93e8f>] start_kernel+0x3e2/0x3ef
  [<ffffffff81f9343d>] x86_64_start_reservations+0x38/0x3a
  [<ffffffff81f93529>] x86_64_start_kernel+0xea/0xed
 handlers:
 [<ffffffff81411670>] serial8250_interrupt
 Disabling IRQ #54

Fix this by handling interrupt only in one place.

The issue is discussed here: https://github.com/andy-shev/linux/issues/5

Moreover this also fixes another bug when Rx DMA returns wrong residue and we
can't rely on it.

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:20:23 +01:00
Jason Uy 6a171b2993 serial: 8250_dw: Allow hardware flow control to be used
In the most common use case, the Synopsys DW UART driver does not
set the set_termios callback function.  This prevents UPSTAT_AUTOCTS
from being set when the UART flag CRTSCTS is set.  As a result, the
driver will use software flow control as opposed to hardware flow
control.

To fix the problem, the set_termios callback function is set to the
DW specific function.  The logic to set UPSTAT_AUTOCTS is moved so
that any clock error will not affect setting the hardware flow
control.

Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Jason Uy <jason.uy@broadcom.com>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:20:23 +01:00
Laurent Pinchart dfc80387ae serial: sh-sci: Compute the regshift value for SCI ports
SCI instances found in SH SoCs have different spacing between registers
depending on the SoC. The platform data contains a regshift field that
tells the driver by how many bits to shift the register offset to
compute its address. We can compute the regshift value automatically
based on the memory resource size, there's no need to pass the value
through platform data.

Fix the sh7750 SCI and sh7760 SIM port memory resources length to ensure
proper computation of the regshift value.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:17:05 +01:00
Laurent Pinchart 97ed9790c5 serial: sh-sci: Remove unused platform data capabilities field
The field isn't set by any platform but is only used internally in the
driver to hold data parsed from DT. Move it to the sci_port structure.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:17:05 +01:00
Laurent Pinchart d5cb1319a9 serial: sh-sci: Remove manual break debouncing
The sh-sci driver implements manual break debouncing for a few SH
platforms by reading the value of the RX pin port register. This feature
is optional and the driver considers all negative or zero values of the
platform data port_reg field as invalid. As the four platforms that set
the field to a register address all use an address higher than
0x7fffffff, the driver will always consider the value as invalid and
never perform debouncing. The feature is unused, remove it.

Debouncing could be implemented properly in the future using the pinctrl
and GPIO APIs if desired.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:17:05 +01:00
Laurent Pinchart 219fb0c143 serial: sh-sci: Remove the platform data dma slave rx/tx channel IDs
Only SH platforms still use platform data for the sh-sci, and none of
them declare DMA channels connected to the SCI. Remove the corresponding
platform data fields and simplify the driver accordingly.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:17:05 +01:00
Laurent Pinchart b2f20ed9c4 serial: sh-sci: Extend sci_port_params with more port parameters
The fifo size, overrun register and mask, sampling rate mask and error
mask all depend on the port type only and don't need to be computed at
runtime. Add them to the sci_port_parameters structure.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:17:05 +01:00
Laurent Pinchart daf5a8959a serial: sh-sci: Constify platform data
The driver modifies platform data for internal purpose only. Fix that
and make the platform data structure const.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:17:05 +01:00
Laurent Pinchart e095ee6b44 serial: sh-sci: Replace regmap array with port parameters
Turn the regmap two-dimensional array to an array of port parameters and
store a pointer to the port parameters in the sci_port structure. This
will allow handling additional port type dependent parameters.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:17:05 +01:00
Laurent Pinchart 40b34ddb03 serial: sh-sci: Remove initialization of zero fields in sci_port_params
The compiler zeros uninitialized fields, don't zero them manually.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:17:05 +01:00
Laurent Pinchart a752ba18af serial: sh-sci: Fix register offsets for the IRDA serial port
Even though most of its registers are 8-bit wide, the IRDA has two
16-bit registers that make it a 16-bit peripheral and not a 8-bit
peripheral with addresses shifted by one. Fix the registers offset in
the driver and the platform data regshift value.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:17:05 +01:00
Laurent Pinchart 3d73f32bfa serial: sh-sci: Don't rely on platform data flags when not needed
The UPF_BOOT_AUTOCONF platform data flag is set by all platforms,
hardcode it.

The UPF_IOREMAP flag is set by a single SH platform and thus needs to be
kept. However, for ARM platforms, we can base the decision on whether an
OF node is present and bypass the platform data flags completely.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:17:04 +01:00
Laurent Pinchart 9f8325b3c1 serial: sh-sci: Set the SCSCR TE and RE bits in the driver
The Transmit Enable and Receive Enable bits are set in the scscr field
of all instances of the sh-sci platform data. Set them in the driver
directly to prepare for their removal from platform data.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 14:17:04 +01:00
Greg Kroah-Hartman 11cca3d12f Merge 4.10-rc4 into tty-next
We want the serial/tty fixes in here as well to build on top of.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-16 16:57:54 +01:00
David Lechner a2d6a987bf serial: 8250: Add new port type for TI DA8xx/66AK2x
This adds a new UART port type for TI DA8xx/OMAPL13x/AM17xx/AM18xx/66AK2x.
These SoCs have standard 8250 registers plus some extra non-standard
registers.

The UART will not function unless the non-standard Power and Emulation
Management Register (PWREMU_MGMT) is configured correctly. This is
currently handled in arch/arm/mach-davinci/serial.c for non-device-tree
boards. Making this part of the UART driver will allow UART to work on
device-tree boards as well and the mach code can eventually be removed.

Signed-off-by: David Lechner <david@lechnology.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:25 +01:00
Jean Delvare 194588930c serial: 8250_mid: make option visible
Hiding tristate options with "if EXPERT" is usually not a good idea.
You can decide that the driver should be included by default, but you
don't know if the user wants it built-in or as a module. Hiding the
option prevents the user from making that decision.

This is even more problematic when said option selects other options.
You end up with several device drivers forcibly built into the kernel.

In this specific case, drivers 8250_mid, virt-dma, hsu_dma and
hsu_dma_pci end up being built-in as soon as SERIAL_8250=y. It is
very common for distribution kernels to build the subsystem core code
into the kernel, because almost everybody will need it, but build all
the device drivers as modules. This should be made possible.

So drop the "if EXPERT" and make SERIAL_8250_MID visible.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Fixes: 1fc969c759 ("serial: 8250_mid: make module available only on X86")
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:25 +01:00
Jean Delvare dce22df190 serial: 8250_lpss: make option visible
Hiding tristate options with "if EXPERT" is usually not a good idea.
You can decide that the driver should be included by default, but you
don't know if the user wants it built-in or as a module. Hiding the
option prevents the user from making that decision.

This is even more problematic when said option selects other options.
You end up with several device drivers forcibly built into the kernel.

In this specific case, drivers 8250_lpss, dw_dmac_core and
dw_dmac_pci end up being built-in as soon as SERIAL_8250=y. It is
very common for distribution kernels to build the subsystem core code
into the kernel, because almost everybody will need it, but build all
the device drivers as modules. This should be made possible.

So drop the "if EXPERT" and make SERIAL_8250_LPSS visible.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Fixes: a13e19cf3d ("serial: 8250_lpss: split LPSS driver to separate module")
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:25 +01:00
Jean Delvare f1e8c710e2 serial: 8250_pci: make option visible
Hiding tristate options with "if EXPERT" is usually not a good idea.
You can decide that the driver should be included by default, but you
don't know if the user wants it built-in or as a module. Hiding the
option prevents the user from making that decision.

In this specific case, driver 8250_pci ends up being built-in as soon
as SERIAL_8250=y. It is very common for distribution kernels to build
the subsystem core code into the kernel, because almost everybody
will need it, but build all the device drivers as modules. This
should be made possible.

So drop the "if EXPERT" and make SERIAL_8250_PCI visible.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:25 +01:00
Alexey Brodkin 699a11ba7e serial: 8250_port: Remove dangerous pr_debug()
With CONFIG_DYNAMIC_DEBUG if dyndbg enables debug output in
8250_port.c deadlock happens inevitably on UART IRQ handling.

That's the problematic execution path:
---------------------------->8------------------------
UART IRQ:
  serial8250_interrupt() ->
    serial8250_handle_irq(): lock "port->lock" ->
      pr_debug() ->
        serial8250_console_write(): bump in locked "port->lock".

      OR (if above pr_debug() gets removed):
      serial8250_tx_chars() ->
        pr_debug() ->
          serial8250_console_write(): bump in locked "port->lock".
---------------------------->8------------------------

So let's get rid of those not that much useful debug entries.

Discussed problem could be easily reproduced with QEMU for x86_64.
As well as this fix could be mimicked with muting of dynamic debug for
the problematic lines as simple as:
---------------------------->8------------------------
dyndbg="+p; file 8250_port.c line 1756 -p; file 8250_port.c line 1822 -p"
---------------------------->8------------------------

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Phillip Raffeck <phillip.raffeck@fau.de>
Cc: Anton Wuerfel <anton.wuerfel@fau.de>
Cc: "Matwey V. Kornilov" <matwey@sai.msu.ru>
Cc: Yegor Yefremov <yegorslists@googlemail.com>
Cc: Thor Thayer <tthayer@opensource.altera.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:25 +01:00
Fabio Estevam 7b7e8e8e8f serial: imx: Allow passing 'rst-gpios' for rs485 mode
According to Documentation/devicetree/bindings/serial/serial.txt the
generic 'rts-gpios' property can be used to specify the GPIO for RTS
functionality.

Currently it is not possible to use the imx UART port in rs485 mode when
the 'rts-gpios' property is passed in the device tree.

The imx uart driver only checks for the presence of the built-in RTS pin,
via 'uart-has-rtscts' property and disable the rs485 flag if this property
is absent.

So fix this logic by also checking if RTS pin has been passed via GPIO.

Tested on a imx6dl based board.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Tested-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:25 +01:00
Andy Shevchenko 3f08087826 serial: 8250_lpss: avoid potential kernel crash when remove
This is a follow up to the commit a9b01b5823 ("serial: 8250_mid fix calltrace
when hotplug 8250 serial controller") in which the kernel crash was described
for another 8250 based driver. It appears that we have the very same issue in
8250_lpss. Fix it by unregistering serial driver first.

Cc: Liwei Song <liwei.song@windriver.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:25 +01:00
Javier Martinez Canillas abe81f3b8e tty: serial: msm: Fix module autoload
If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.

Export the module alias information using the MODULE_DEVICE_TABLE() macro.

Before this patch:

$ modinfo drivers/tty/serial/msm_serial.ko | grep alias
$

After this patch:

$ modinfo drivers/tty/serial/msm_serial.ko | grep alias
alias:          of:N*T*Cqcom,msm-uartdmC*
alias:          of:N*T*Cqcom,msm-uartdm
alias:          of:N*T*Cqcom,msm-uartC*
alias:          of:N*T*Cqcom,msm-uart

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:25 +01:00
Matwey V. Kornilov 9c4b60fe53 serial: 8250: moxa: Store num_ports in brd
When struct moxa8250_board is allocated, then num_ports should
be initialized in order to use it later in moxa8250_remove.

Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:25 +01:00
Ji-Ze Hong (Peter Hong) 6def047c29 serial: 8250_fintek: Add resource check for Fintek F81504/508/512
Add resource type check for Fintek F81504/508/512, BAR3/4/5 must be
IORESOURCE_IO.

Fintek is trying to make F81504/508/512 works on MMIO interface, but
it's still in progress. We found some issue when the experiment IC
when the BAR3/4/5 is IORESOURCE_MEM. It'll cause wrong operation with
IO resource. So we'll add the resource check for this.

Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:24 +01:00
John Crispin 552df698e9 tty: update my email address
This patch updates my email address as I no longer have access to the old
one.

Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:24 +01:00
Martin Blumenstingl ec84aa0a92 tty: serial: lantiq: implement earlycon support
This allows enabling earlycon for devices with a Lantiq serial console
by splitting lqasc_serial_port_write() from lqasc_console_write() and
re-using the new function for earlycon's write callback.

The kernel-parameter name matches the driver name ("lantiq"), similar
to how other drivers implement this.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:24 +01:00
Christophe JAILLET 2aaa957361 serial: pic32_uart: Fix 'request_irq' and 'free_irq' inconsistancy
'request_irq' and 'free_irq' should have the same 'dev_id'.
Here one uses 'port', and the other one uses 'sport'.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:24 +01:00
Marek Szyprowski ba3d6f8f10 serial: samsung: Simplify DMA engine initialization code
dma_request_slave_channel_compat() requires filter function and mask, which
are not needed on device tree based platforms, so simplify the code by
calling the more appropriate dma_request_chan() function. This additionally
gives us proper error handling, because the new function returns error
codes instead of NULL on failure.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:24 +01:00
Wolfgang Ocker f87fa71e6f serial: mxs-auart: support CMSPAR termios cflag
If CMSPAR is set in the c_cflag of termios, "stick" parity is enabled.

Tested on an i.MX28 system

Signed-off-by: Wolfgang Ocker <weo@reccoware.de>
Acked-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:24 +01:00
Alexander Shiyan 11652fc7b7 serial: max310x: Add support for newer silicon revisions
New IC MAX14830 has 0xB4 silicon revision ID.
This patch adds support for such ICs.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:24 +01:00
Nikita Yushchenko 54a44d54be tty: serial: fsl_lpuart: fix del_timer_sync() vs timer routine deadlock
Problem found via lockdep:

- lpuart_set_termios() calls del_timer_sync(&sport->lpuart_timer) while
  holding sport->port.lock

- sport->lpuart_timer routine is lpuart_timer_func() that calls
  lpuart_copy_rx_to_tty() that acquires same lock.

To fix, move Rx DMA stopping out of lock, as it already is in other places
in the same file.

While at it, also make Rx DMA start/stop code to look the same is in
other places in the same file.

Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Tested-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:24 +01:00
Pan Bian 623ac1d4a5 tty: serial: sh-sci: set error code when kasprintf fails
When the call to kasprintf() returns a NULL pointer, function
sci_request_irq() frees the preallocated memory and returns 0 is
returned. Because 0 means no error, the caller of sci_request_irq()
will keep going, and the freed memory may be used or freed again. To
avoid the above issue, this patch assigns "-ENOMEM" to the return
variable ret.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=188691

Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12 11:51:24 +01:00
Herbert Xu 6741f551a0 Revert "tty: serial: 8250: add CON_CONSDEV to flags"
This commit needs to be reverted because it prevents people from
using the serial console as a secondary console with input being
directed to tty0.

IOW, if you boot with console=ttyS0 console=tty0 then all kernels
prior to this commit will produce output on both ttyS0 and tty0
but input will only be taken from tty0.  With this patch the serial
console will always be the primary console instead of tty0,
potentially preventing people from getting into their machines in
emergency situations.

Fixes: d03516df83 ("tty: serial: 8250: add CON_CONSDEV to flags")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-11 08:35:17 +01:00
Daniel Jedrychowski 2bed8a8e70 Clearing FIFOs in RS485 emulation mode causes subsequent transmits to break
When in RS485 emulation mode, __do_stop_tx_rs485() calls
serial8250_clear_fifos().  This not only clears the FIFOs, but also sets
all bits in their control register (UART_FCR) to 0.

One of the effects of this is the disabling of the FIFOs, which turns
them into single-byte holding registers.  The rest of the driver doesn't
know this, which results in the lions share of characters passed into a
write call to be dropped.

(I can supply logic analyzer screenshots if necessary)

This fix replaces the serial8250_clear_fifos() call to
serial8250_clear_and_reinit_fifos() - this prevents the "dropped
characters" issue from manifesting again while retaining the requirement
of clearing the RX FIFO after transmission if the SER_RS485_RX_DURING_TX
flag is disabled.

Signed-off-by: Daniel Jedrychowski <avistel@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-11 08:35:17 +01:00
Gabriel Krisman Bertazi c130b666a9 8250_pci: Fix potential use-after-free in error path
Commit f209fa03fc ("serial: 8250_pci: Detach low-level driver during
PCI error recovery") introduces a potential use-after-free in case the
pciserial_init_ports call in serial8250_io_resume fails, which may
happen if a memory allocation fails or if the .init quirk failed for
whatever reason).  If this happen, further pci_get_drvdata will return a
pointer to freed memory.

This patch reworks the PCI recovery resume hook to restore the old priv
structure in this case, which should be ok, since the ports were already
detached. Such error during recovery causes us to give up on the
recovery.

Fixes: f209fa03fc ("serial: 8250_pci: Detach low-level driver during
  PCI error recovery")
Reported-by: Michal Suchanek <msuchanek@suse.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-11 08:35:17 +01:00
Richard Genoud b389f173aa tty/serial: atmel: RS485 half duplex w/DMA: enable RX after TX is done
When using RS485 in half duplex, RX should be enabled when TX is
finished, and stopped when TX starts.

Before commit 0058f0871e ("tty/serial: atmel: fix RS485 half
duplex with DMA"), RX was not disabled in atmel_start_tx() if the DMA
was used. So, collisions could happened.

But disabling RX in atmel_start_tx() uncovered another bug:
RX was enabled again in the wrong place (in atmel_tx_dma) instead of
being enabled when TX is finished (in atmel_complete_tx_dma), so the
transmission simply stopped.

This bug was not triggered before commit 0058f0871e
("tty/serial: atmel: fix RS485 half duplex with DMA") because RX was
never disabled before.

Moving atmel_start_rx() in atmel_complete_tx_dma() corrects the problem.

Cc: stable@vger.kernel.org
Reported-by: Gil Weber <webergil@gmail.com>
Fixes: 0058f0871e
Tested-by: Gil Weber <webergil@gmail.com>
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-11 08:18:45 +01:00
Richard Genoud 89d8232411 tty/serial: atmel_serial: BUG: stop DMA from transmitting in stop_tx
If we don't disable the transmitter in atmel_stop_tx, the DMA buffer
continues to send data until it is emptied.
This cause problems with the flow control (CTS is asserted and data are
still sent).

So, disabling the transmitter in atmel_stop_tx is a sane thing to do.

Tested on at91sam9g35-cm(DMA)
Tested for regressions on sama5d2-xplained(Fifo) and at91sam9g20ek(PDC)

Cc: <stable@vger.kernel.org> (beware, this won't apply before 4.3)
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-11 08:18:45 +01:00