gpio/omap: ensure gpio context is initialised

Commit a2797be (gpio/omap: force restore if context loss is not
detectable) broke gpio support for OMAP when booting with device-tree
because a restore of the gpio context being performed without ever
initialising the gpio context. In other words, the context restored was
bad.

This problem could also occur in the non device-tree case, however, it
is much less likely because when booting without device-tree we can
detect context loss via a platform specific API and so context restore
is performed less often.

Nevertheless we should ensure that the gpio context is initialised
on the first pm-runtime resume for gpio banks that could lose their
state regardless of whether we are booting with device-tree or not.

The context loss count was being initialised on the first pm-runtime
suspend following a resume, by populating the get_count_loss_count()
function pointer after the first pm-runtime resume. To make the code
more readable and logical, initialise the context loss count on the
first pm-runtime resume if the context is not yet valid.

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Santosh Shilimkar<santosh.shilimkar@ti.com>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpio: mcp23s08: Fix build error when CONFIG_SPI_MASTER=y && CONFIG_I2C=m

This patch fixes below build error when CONFIG_SPI_MASTER=y && CONFIG_I2C=m &&
CONFIG_GPIO_MCP23S08=y.

  LD      init/built-in.o
drivers/built-in.o: In function `mcp23017_write':
clkdev.c:(.text+0x1e14): undefined reference to `i2c_smbus_write_word_data'
drivers/built-in.o: In function `mcp23017_read':
clkdev.c:(.text+0x1e24): undefined reference to `i2c_smbus_read_word_data'
drivers/built-in.o: In function `mcp23008_write':
clkdev.c:(.text+0x1e8c): undefined reference to `i2c_smbus_write_byte_data'
drivers/built-in.o: In function `mcp23008_read':
clkdev.c:(.text+0x1e98): undefined reference to `i2c_smbus_read_byte_data'
drivers/built-in.o: In function `mcp23008_read_regs':
clkdev.c:(.text+0x1ed0): undefined reference to `i2c_smbus_read_byte_data'
drivers/built-in.o: In function `mcp23s08_init':
clkdev.c:(.init.text+0x30): undefined reference to `i2c_register_driver'
drivers/built-in.o: In function `mcp23s08_exit':
clkdev.c:(.exit.text+0x30): undefined reference to `i2c_del_driver'
make: *** [vmlinux] Error 1

When CONFIG_I2C=m, meaning we can't build the drivers in with I2C support.
Thus don't allow the drivers to be compiled as built-in when CONFIG_I2C=m.

The real fix though is to break the driver apart into a SPI part, an I2C part
and a common part. But that's something for 3.11 while this is something for
3.10/stable.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpio-langwell: fix irq conflicts when DT is not used

When DT is not used IOAPIC does not register irq domain. As result
IOAPIC won't care about gpio-langwell's virq and may cause conflict if
an irq number is equal to gpio-langwell's virq mapped beforehand.

This patch tells gpio_langwell to not ignore irq_base if != 0 and
preferably use it to avoid the conflict.

If DT is used, irq_base can safely be 0.

Signed-off-by: David Cohen <david.a.cohen@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpio: mxs: Use set and clear capabilities of the gpio controller

The current driver doesn't use the set and clear registers found on the
mxs gpio controller.

This leads the generic gpio controller to be using some internal value
to avoid looking up the value stored in the registers, making it behave
pretty much like a cache.

This raises some coherency problem when a gpio is not modified by the
gpio controller, while it can easily be fixed by using the set and clear
registers.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpio: Don't override the error code in probe error handling

Otherwise, we return 0 in probe error paths when gpiochip_remove() returns 0.
Also show error message if gpiochip_remove() fails.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Cc: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Cc: Denis Turischev <denis@compulab.co.il>
Cc: Lars Poeschel <poeschel@lemonage.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Merge tag 'gpio-fixes-v3.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO fixes from Linus Walleij:
 - An OMAP fix that makes ethernet work again.
 - Fix for build problem when building the MCP23S08 driver as module.
 - IRQ conflicts in the Langwell driver.
 - Fix IRQ coherency issues in the MXS driver.
 - Return correct errorcode on errorpath when removing GPIO chips.

* tag 'gpio-fixes-v3.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: Don't override the error code in probe error handling
  gpio: mxs: Use set and clear capabilities of the gpio controller
  gpio-langwell: fix irq conflicts when DT is not used
  gpio: mcp23s08: Fix build error when CONFIG_SPI_MASTER=y && CONFIG_I2C=m
  gpio/omap: ensure gpio context is initialised