The driver core clears the driver data to NULL after device_release
or on probe failure, since commit 0998d063
(device-core: Ensure drvdata = NULL when no driver is bound).
Thus, it is not needed to manually clear the device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Acked-by: NBarry Song <baohua.song@csr.com>
Acked-by: NTony Prisk <linux@prisktech.co.nz>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Since commit ab78029e (drivers/pinctrl: grab default handles from device core),
we can rely on device core for setting the default pins. Compile tested only.

Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Since commit 0c375501 (serial: imx: enable the clocks for console), the
imx_startup() function calls clk_prepare_enable conditionally, so we
need to call clk_disable_unprepare inside imx_shutdown() under the same
condition to avoid unbalanced clock calls.

This avoids the following warning:

------------[ cut here ]------------
WARNING: CPU: 0 PID: 70 at drivers/clk/clk.c:780 __clk_disable+0x68/0x84()
Modules linked in:
CPU: 0 PID: 70 Comm: mountall Not tainted 3.10.0-rc4-next-20130607+ #435
Backtrace:
[<800116a4>] (dump_backtrace+0x0/0x10c) from [<80011844>] (show_stack+0x18/0x1c)
 r6:8069f4e8 r5:0000030c r4:00000000 r3:00000000
[<8001182c>] (show_stack+0x0/0x1c) from [<8053bce0>] (dump_stack+0x78/0x94)
[<8053bc68>] (dump_stack+0x0/0x94) from [<80023df8>] (warn_slowpath_common+0x6c/0x8c)
 r4:00000000 r3:00000000
[<80023d8c>] (warn_slowpath_common+0x0/0x8c) from [<80023e3c>] (warn_slowpath_null+0x24/0x2c)
 r8:bf2ed008 r7:bfaa9810 r6:000f0013 r5:bf824b80 r4:bf824b80
[<80023e18>] (warn_slowpath_null+0x0/0x2c) from [<8041af84>] (__clk_disable+0x68/0x84)
[<8041af1c>] (__clk_disable+0x0/0x84) from [<8041b098>] (clk_disable+0x20/0x2c)
 r4:600f0013 r3:00000001
[<8041b078>] (clk_disable+0x0/0x2c) from [<802c93e8>] (imx_shutdown+0xbc/0xec)
 r5:bf824b80 r4:bfaa9810
[<802c932c>] (imx_shutdown+0x0/0xec) from [<802c63a0>] (uart_port_shutdown+0x34/0x40)
 r5:bf86f860 r4:bfaa9810
[<802c636c>] (uart_port_shutdown+0x0/0x40) from [<802c68c0>] (uart_shutdown+0x98/0xc4)
 r4:bf86f800 r3:00000000
[<802c6828>] (uart_shutdown+0x0/0xc4) from [<802c7514>] (uart_close+0x5c/0x198)
 r7:bfaa9810 r6:bf274400 r5:bf86f86c r4:bf86f800
[<802c74b8>] (uart_close+0x0/0x198) from [<802ac648>] (tty_release+0xf8/0x500)
[<802ac550>] (tty_release+0x0/0x500) from [<800c5a30>] (__fput+0x9c/0x208)
[<800c5994>] (__fput+0x0/0x208) from [<800c5bac>] (____fput+0x10/0x14)
[<800c5b9c>] (____fput+0x0/0x14) from [<80040234>] (task_work_run+0xb4/0xec)
[<80040180>] (task_work_run+0x0/0xec) from [<80029238>] (do_exit+0x2b0/0x920)
 r8:8000e144 r7:000000f8 r6:bf306300 r5:00000000 r4:bfac1180
[<80028f88>] (do_exit+0x0/0x920) from [<80029a4c>] (do_group_exit+0x50/0xd4)
 r7:000000f8
[<800299fc>] (do_group_exit+0x0/0xd4) from [<80029ae8>] (__wake_up_parent+0x0/0x28)
 r7:000000f8 r6:00000001 r5:0006f7ae r4:0006f79a
[<80029ad0>] (SyS_exit_group+0x0/0x18) from [<8000dfc0>] (ret_fast_syscall+0x0/0x30)
---[ end trace 16d080eb7efea4e9 ]---
Reported-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The console's clocks are disabled after the uart driver is probed.
It makes that we can see less log from the console now
(though we still can get all the log by the `dmesg`).

So enable the clocks for console, and we can see all the log again.

This patch also disables the sport->clk_per when we fail to enable
the sport->clk_ipg;
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When CONFIG_SERIAL_IMX_CONSOLE is not selected the following build warnings
appear:

drivers/tty/serial/imx.c:274:13: warning: 'imx_port_ucrs_save' defined but not used [-Wunused-function]
drivers/tty/serial/imx.c:283:13: warning: 'imx_port_ucrs_restore' defined but not used [-Wunused-function]

imx_port_ucrs_save() and imx_port_ucrs_restore() are only used when
CONFIG_CONSOLE_POLL or CONFIG_SERIAL_IMX_CONSOLE are selected, so protect these
functions declaration with a proper ifdef.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Current code opens the clocks when the uart driver is probed.
This will wastes some power if several uarts are enabled, but not really
used.

So close these clocks for uart, and enable the clocks only when
the uart is used.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The uart works in the DCE mode by default, but sometime we need it
works at the DTE mode.

This patch adds the support for the DTE mode.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We only want to enable hardware flow control if RTS/CTS pins
are connected.
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch enables the overrun error (ORE) interrupt and increases the
counter in case of overrun.
Signed-off-by: NAlexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit 677fe555 (serial: imx: Fix recursive locking bug) introduces an
uninitialized variable warning as below.

  CC      drivers/tty/serial/imx.o
drivers/tty/serial/imx.c: In function ‘imx_console_write’:
include/linux/spinlock.h:340:2: warning: ‘flags’ may be used uninitialized in this function [-Wuninitialized]
drivers/tty/serial/imx.c:1214:16: note: ‘flags’ was declared here

Initialize the variable to suppress the warning.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Acked-by: NDirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 9ec1882d (tty: serial: imx: console write routing is unsafe
on SMP) introduced a recursive locking bug in imx_console_write().

The callchain is:

imx_rxint()
  spin_lock_irqsave(&sport->port.lock,flags);
  ...
  uart_handle_sysrq_char();
    sysrq_function();
      printk();
        imx_console_write();
          spin_lock_irqsave(&sport->port.lock,flags); <--- DEAD

The bad news is that the kernel debugging facilities can dectect the
problem, but the printks never surface on the serial console for
obvious reasons.

There is a similar issue with oops_in_progress. If the kernel crashes
we really don't want to be stuck on the lock and unable to tell what
happened.

In general most UP originated drivers miss these checks and nobody
ever notices because CONFIG_PROVE_LOCKING seems to be still ignored by
a large number of developers.

The solution is to avoid locking in the sysrq case and trylock in the
oops_in_progress case.

This scheme is used in other drivers as well and it would be nice if
we could move this to a common place, so the usual copy/paste/modify
bugs can be avoided.

Now there is another issue with this scheme:

CPU0 	    	     	 CPU1
printk()
			 rxint()
			   sysrq_detection() -> sets port->sysrq
			 return from interrupt
  console_write()
     if (port->sysrq)
     	avoid locking

port->sysrq is reset with the next receive character. So as long as
the port->sysrq is not reset and this can take an endless amount of
time if after the break no futher receive character follows, all
console writes happen unlocked.

While the current writer is protected against other console writers by
the console sem, it's unprotected against open/close or other
operations which fiddle with the port. That's what the above mentioned
commit tried to solve.

That's an issue in all drivers which use that scheme and unfortunately
there is no easy workaround. The only solution is to have a separate
indicator port->sysrq_cpu. uart_handle_sysrq_char() then sets it to
smp_processor_id() before calling into handle_sysrq() and resets it to
-1 after that. Then change the locking check to:

     if (port->sysrq_cpu == smp_processor_id())
     	 locked = 0;
     else if (oops_in_progress)
         locked = spin_trylock_irqsave(port->lock, flags);
     else
  	 spin_lock_irqsave(port->lock, flags);

That would force all other cpus into the spin_lock path. Problem
solved, but that's way beyond the scope of this fix and really wants
to be implemented in a common function which calls the uart specific
write function to avoid another gazillion of hard to debug
copy/paste/modify bugs.
Reported-and-tested-by: NTim Sander <tim@krieglstein.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: stable <stable@vger.kernel.org>  # 3.6+
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit cdc8da39.

In my attempt to fix a build warning on arm randconfig a build error on
imx_v6_v7_defconfig was introduced, so revert it for now.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If CONFIG_CONSOLE_POLL is not defined, the following build warning happens:

drivers/tty/serial/imx.c:274:13: warning: 'imx_port_ucrs_save' defined but not used [-Wunused-function]
drivers/tty/serial/imx.c:283:13: warning: 'imx_port_ucrs_restore' defined but not used [-Wunused-function]

Move imx_port_ucrs_saver/restore under CONFIG_CONSOLE_POLL ifdef block to fix it.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit 2e124b4a (TTY: switch tty_flip_buffer_push) introduced the following
build warning:

drivers/tty/serial/imx.c:519:21: warning: unused variable 'tty' [-Wunused-variable]

Remove the unused 'tty' variable.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

Now, the one where most of tty_port_tty_get gets removed:
tty_flip_buffer_push.

IOW we also closed all the races in drivers not using tty_port_tty_get
at all yet.

Also we move tty_flip_buffer_push declaration from include/linux/tty.h
to include/linux/tty_flip.h to all others while we are changing it
anyway.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

tty_insert_flip_char is the next one to proceed. This one is used all
over the code, so the patch is huge.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

devm_* APIs are device managed and make cleanup and exit code simpler
and easier.

Cc: Shawn Guo <shawn.guo@linaro.org>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Silences checkpatch warnings.

Cc: Shawn Guo <shawn.guo@linaro.org>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Silences the following checkpatch error:
ERROR: that open brace { should be on the previous line

Cc: Shawn Guo <shawn.guo@linaro.org>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Silences the following checkpatch warning:
WARNING: Use #include <linux/io.h> instead of <asm/io.h>

Cc: Shawn Guo <shawn.guo@linaro.org>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fixed checkpatch errors and warnings related to incorrect spacing.

Cc: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

platform_get_drvdata always retrun a valid value after probe succeed.

It also fixed smatch warnings:
drivers/tty/serial/imx.c:1376 serial_imx_suspend() warn: variable dereferenced before check 'sport' (see line 1372)
drivers/tty/serial/imx.c:1392 serial_imx_resume() warn: variable dereferenced before check 'sport' (see line 1388)
Signed-off-by: NRichard Zhao <richard.zhao@freescale.com>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: NRichard Zhao <richard.zhao@freescale.com>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Platform data for device drivers should be defined in
include/linux/platform_data/*.h, not in the architecture
and platform specific directories.

This moves such data out of the imx include directories
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NNicolas Pitre <nico@linaro.org>
Acked-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: NSascha Hauer <kernel@pengutronix.de>
Acked-by: NVinod Koul <vinod.koul@linux.intel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Dan Williams <djbw@fb.com>
Cc: "Ben Dooks (embedded platforms)" <ben-linux@fluff.org>
Cc: "Wolfram Sang (embedded platforms)" <w.sang@pengutronix.de>
Cc: Chris Ball <cjb@laptop.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Liam Girdwood <lrg@ti.com>
Cc: Javier Martin <javier.martin@vista-silicon.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>

These error paths are used more often now after deep changes to the
clock code and pinctrl is still new for imx. So help debugging and give
clues in the boot log.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove the clock configuration from imx_setup_ufcr(). This
isn't needed here and will cause garbage output if done.

To be be sure that we only touch the bits we want (TXTL and RXTL)
we have to mask out all other bits of the UFCR register. Add
one non-existing bit macro for this, too (bit 6, DCEDTE on i.MX6).
Signed-off-by: NDirk Behme <dirk.behme@de.bosch.com>
CC: Shawn Guo <shawn.guo@linaro.org>
CC: Sascha Hauer <s.hauer@pengutronix.de>
CC: Troy Kisky <troy.kisky@boundarydevices.com>
CC: Xinyu Chen <xinyu.chen@freescale.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The console feature's write routing is unsafe on SMP with
the startup/shutdown call.

There could be several consumers of the console
* the kernel printk
* the init process using /dev/kmsg to call printk to show log
* shell, which open /dev/console and write with sys_write()

The shell goes into the normal uart open/write routing,
but the other two go into the console operations.
The open routing calls imx serial startup, which will write USR1/2
register without any lock and critical with imx_console_write call.

Add a spin_lock for startup/shutdown/console_write routing.

This patch is a port from Freescale's Android kernel.
Signed-off-by: NXinyu Chen <xinyu.chen@freescale.com>
Tested-by: NDirk Behme <dirk.behme@de.bosch.com>
CC: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This prepares *of_device_id.data becoming const. Without this change the
following warning would occur:

	drivers/tty/serial/imx.c: In function 'serial_imx_probe_dt':
	drivers/tty/serial/imx.c:1430:17: warning: assignment discards 'const' qualifier from pointer target type [enabled by default]
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>

As the part of the effort to enable SPARE_IRQ for imx platform,
the macro MXC_INTERNAL_IRQS will be removed.  The imx serial driver
has a references to it for a decision on flags of request_irq call
based on rtsirq is beyond MXC_INTERNAL_IRQS.  However the searching
on imx platform code tells that rtsirq will never be beyond
MXC_INTERNAL_IRQS.  That said, the check, consequently the reference
to MXC_INTERNAL_IRQS are not needed, so remove them.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Cc: linux-serial@vger.kernel.org
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Acked-by: NDong Aisheng <dong.aisheng@linaro.org>

This is only cosmetic for now. In case that

	http://mid.gmane.org/1335171381-24869-1-git-send-email-u.kleine-koenig@pengutronix.de

will be applied, it fixes a warning

	drivers/tty/serial/imx.c: In function 'serial_imx_probe_dt':
	drivers/tty/serial/imx.c:1430:17: warning: assignment discards 'const' qualifier from pointer target type [enabled by default]

though.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Cc: linux-serial@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Acked-by: NDong Aisheng <dong.aisheng@linaro.org>

the current i.MX clock support groups together unrelated clocks
to a single clock which is then used by the driver. This can't
be accomplished with the generic clock framework so we instead
request the individual clocks in the driver. For i.MX there are
generally three different clocks:

ipg: bus clock (needed to access registers)
ahb: dma relevant clock, sometimes referred to as hclk in the datasheet
per: bit clock, pixel clock

This patch changes the driver to request the individual clocks.
Currently all clk_get will get the same clock until the SoCs
are converted to the generic clock framework
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>

It's for migrating to generic clk framework API.
Signed-off-by: NRichard Zhao <richard.zhao@linaro.org>
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>

del_timer_sync() acquires its own lock and doesn't have to be nested
within the spinlock of sport->port.lock in imx_set_termios(),  which
will cause potential deadlock.  Fix this by moving it outside.

Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NEric Miao <eric.miao@linaro.org>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

These methods are invoked if the iMX uart is used in conjuction with kgdb during
early boot.  In order to access the UART without the interrupts, the kernel uses
the basic polling methods for IO with the device.  With these methods
implemented, it is now possible to enable kgdb during early boot over serial.
Signed-off-by: NSaleem Abdulrasool <compnerd@compnerd.org>
Signed-off-by: NDirk Behme <dirk.behme@gmail.com>
CC: Sascha Hauer <s.hauer@pengutronix.de>
CC: Fabio Estevam <festevam@gmail.com>
CC: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
CC: linux-serial@vger.kernel.org
CC: Alan Cox <alan@linux.intel.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Factor out the uart save/restore functionality instead of
having the same code several times in the driver.
Signed-off-by: NDirk Behme <dirk.behme@gmail.com>
CC: Saleem Abdulrasool <compnerd@compnerd.org>
CC: Sascha Hauer <s.hauer@pengutronix.de>
CC: Fabio Estevam <festevam@gmail.com>
CC: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
CC: linux-serial@vger.kernel.org
CC: Alan Cox <alan@linux.intel.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

When the uart device is instantiated by dt but dt doesn't provide an
alias then better let probing fail instead of falling back to an
unrelated device id used for the line number and no platform data.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

A quick look at of_alias_get_id shows that in the error case it returns
-ENODEV, too, but still it's better style to propagate the value as is.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Jeremy Kerr <jeremy.kerr@canonical.com>
Cc: Jason Liu <jason.hui@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: NJason Liu <jason.hui@linaro.org>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Allow UART to be a source for wakeup from low power mode.

Tested on a MX27PDK by doing:

echo enabled > /sys/devices/platform/imx21-uart.0/tty/ttymxc0/power/wakeup

echo mem > /sys/power/state

and then pressing a key in the console will wakeup the sytem.
Suggested-by: NShawn Guo <shawn.guo@freescale.com>
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Tested-by: NRichard Zhao <richard.zhao@freescale.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>