gpio/omap: fix irq loss while in idle with debounce on

It seems that currently GPIO module is not working correctly during idle
when debounce is enabled - the system almost never responds to button
presses (observed on OMAP3530 ES2.1 and OMAP3630 ES1.2 pandora boards).
Even though wakeups are probably working, it seems that the GPIO module
itself is unable to detect input events and generate interrupts.
OMAP35x TRM also states that:
  "If the debounce clock is inactive, the debounce cell gates all
   input signals and thus cannot be used."

So whenever we are disabling debounce clocks (for PM or other reasons),
be sure the module's debounce feature is disabled too.

Cc: Kevin Hilman <khilman@ti.com>
Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
gpio/omap: fix invalid context restore of gpio bank-0

Currently the gpio _runtime_resume/suspend functions are calling the
get_context_loss_count() platform function if the function is populated for
a gpio bank. This function is used to determine if the gpio bank logic state
needs to be restored due to a power transition. This function will be populated
for all banks, but it should only be called for banks that have the
"loses_context" variable set. It is pointless to call this if loses_context is
false as we know the context will never be lost and will not need restoring.

For all OMAP2+ devices gpio bank-0 is in an always-on power domain and so will
never lose context. We found that the get_context_loss_count() was being called
for bank-0 during the probe and returning 1 instead of 0 indicating that the
context had been lost. This was causing the context restore function to be
called at probe time for this bank and because the context had never been saved,
was restoring an invalid state. This ultimately resulted in a crash [1].

This issue is a regression that was exposed by commit 1b1287032 (gpio/omap: fix
missing check in *_runtime_suspend()).

There are multiple bugs here that need to be addressed ...

1. Why the always-on power domain returns a context loss count of 1? This needs
   to be fixed in the power domain code [2]. However, the gpio driver should not
   assume the loss count is 0 to begin with.
2. The omap gpio driver should never be calling get_context_loss_count for a
   gpio bank in a always-on domain. This is pointless and adds unneccessary
   overhead.
3. The OMAP gpio driver assumes that the initial power domain context loss count
   will be 0 at the time the gpio driver is probed. However, it could be
   possible that this is not the case and an invalid context restore could be
   performed during the probe. To avoid this only populate the
   get_context_loss_count() function pointer after the initial call to
   pm_runtime_get() has occurred. This will ensure that the first
   pm_runtime_put() initialised the loss count correctly.

This patch addresses issues 2 and 3 above.

[1] http://marc.info/?l=linux-omap&m=134065775323775&w=2
[2] http://marc.info/?l=linux-omap&m=134100413303810&w=2

Cc: Kevin Hilman <khilman@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Cc: Franky Lin <frankyl@broadcom.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: NeilBrown <neilb@suse.de>

Reported-by: Franky Lin <frankyl@broadcom.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Franky Lin <frankyl@broadcom.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Tested-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
gpio-sta2x11: don't use pdata if null

If there is no platform data available, the driver shouldn't use the
pointer or it will oops.  Since things will mostly work nonetheless,
(the BIOS may have set up the pins properly), I'd better not fail the
probe even in this case.

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpio/msm_v1: CONFIG_GPIO_MSM_V1 is only available on three SoCs

The feature GPIO_MSM_V1 is only available on three SoCs. On all other MSM SoCs
the INT_GPIO_GROUP{1,2} is undeclared, but Kconfig does allow such
configurations. Therefore the produced configuration is valid, but does not
compile. The problem is fixed by adding the missing Kconfig constraints.

drivers/gpio/gpio-msm-v1.c: In function âmsm_init_gpioâ:
drivers/gpio/gpio-msm-v1.c:629:26: error: 'INT_GPIO_GROUP1' undeclared
drivers/gpio/gpio-msm-v1.c:630:26: error: 'INT_GPIO_GROUP2' undeclared

Signed-off-by: Christian Dietrich <christian.dietrich@informatik.uni-erlangen.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpiolib: wm8994: Pay attention to the value set when enabling as output

Not paying attention to the value being set is a bad thing because it
means that we'll not set the hardware up to reflect what was requested.
Not setting the hardware up to reflect what was requested means that the
caller won't get the results they wanted.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpio: export devm_gpio_request_one

Without this, modules can't use this API, leading to build failures.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
mips: pci-lantiq: Fix check for valid gpio

This patch fixes two checks for valid gpio number, formerly (wrongly)
considering zero as invalid, now using gpio_is_valid().

Signed-off-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpio: fix bits conflict for gpio flags

The bit 2 and 3 in GPIO flag are allocated for the
flag OPEN_DRAIN/OPEN_SOURCE. These bits are reused
for the flag EXPORT/EXPORT_CHANGEABLE and so creating
conflict.
Fix this conflict by assigning bit 4 and 5 for the
flag EXPORT/EXPORT_CHANGEABLE.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpio/mxc: make irqs work for fsl,imx21-gpio devices

The chained handler was set for the platform device with id == 0.
When the gpio devices are instantiated by a device tree, all have id ==
-1 and so the handler was unset resulting in unusable gpio irqs on
i.MX21 and i.MX27 (when using oftree).

Acked-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpio: tps65910: initialize of_node of gpio_chip

Initialize the gpio chip's of_node to the device's node
to work with DT based system.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Merge branch 'kevin' into fixes
Merge tag 'fixes-for-v3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO fixes from Linus Walleij:
 "Yes, this is a *LATE* GPIO pull request with fixes for v3.5.

  Grant moved across the planet and accidentally fell off the grid, so
  he asked me to take over the GPIO merges for a while 10 days ago.

  Since then I went over the archives and collected this pile of fixes,
  and pulled two of them from the TI maintainer Kevin Hilman.  Then
  waited for them to at least hit linux-next once or twice."

GPIO fixes for v3.5:
 - Invalid context restore on bank 0 for OMAP driver in runtime
   suspend/resume cycle
 - Check for NULL platform data in sta-2x11 driver
 - Constrain selection of the V1 MSM GPIO driver to applicable platforms
   (Kconfig issue)
 - Make sure the correct output value is set in the wm8994 driver
 - Export devm_gpio_request_one() so it can be used in modules.
   Apparently some in-kernel modules can be configured to use this
   leading to breakage.
 - Check that the GPIO is valid in the lantiq driver
 - Fix the flag bits introduced for v3.5, so they don't overlap
 - Fix a device tree intialization bug for imx21-compatible devices
 - Carry over the OF node to the TPS65910 GPIO chip struct

* tag 'fixes-for-v3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: tps65910: initialize of_node of gpio_chip
  gpio/mxc: make irqs work for fsl,imx21-gpio devices
  gpio: fix bits conflict for gpio flags
  mips: pci-lantiq: Fix check for valid gpio
  gpio: export devm_gpio_request_one
  gpiolib: wm8994: Pay attention to the value set when enabling as output
  gpio/msm_v1: CONFIG_GPIO_MSM_V1 is only available on three SoCs
  gpio-sta2x11: don't use pdata if null
  gpio/omap: fix invalid context restore of gpio bank-0
  gpio/omap: fix irq loss while in idle with debounce on