The I2C core always reports the MODALIAS uevent as "i2c:<modalias>"
regardless of the mechanism that was used to register the device
(i.e: OF or board code) and the table that is used later to match
the driver with the device (i.e: I2C id table or OF match table).

So drivers needs to export the I2C id table and this be built into
the module or udev won't have the necessary information to autoload
the needed driver module when the device is added.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

The backlight_device_unregister() function tests whether its argument
is NULL and then returns immediately. Thus the test around the call is
not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

IS_ERR_VALUE() makes sense only *if* there could be valid values in
negative error range.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

The Qualcomm PM8941 WLED block is used for backlight and should therefor
be in the backlight framework and not in the LED framework. This moves
the driver and adapts to the backlight api instead.

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Tested-by: Rob Clark <robdclark@gmail.com>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

LP855x backlight device can be enabled by external VDD input. The
'supply' data is used for this purpose. It's kind of private data
which runs internally, so there is no reason to expose to the
platform data.

And devm_regulator_get() is moved from _parse_dt() to _probe().
Regulator consumer(lp855x) can control regulator not only from DT
but also from platform data configuration in a source file such
like board-*.c.

Signed-off-by: Milo Kim <milo.kim@ti.com>
Acked-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Pull backlight updates from Lee Jones:
 "Changes to existing drivers:

   - supply MODULE_DEVICE_TABLE() to ensure probing
   - constify struct; da9052_bl
   - enable compile test; lcd_l4f00242t03, lcd_lms283fg05, backlight_gpio
   - suspend/resume bugfix; lp855x_bl
   - devm_gpiod_get_optional() API fixup; pwm_bl
   - error handling fixup; backlight"

* tag 'backlight-for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: Change the return type of backlight_update_status() to int
  backlight: pwm_bl: Simplify usage of devm_gpiod_get_optional
  backlight: lp855x: Don't clear level on suspend/blank
  backlight: Allow compile test of GPIO consumers if !GPIOLIB
  video: backlight: da9052: Constify platform_device_id
  gpio-backlight: Discover driver during boot time

Since 39b2bbe3d715 (gpio: add flags argument to gpiod_get*() functions),
the gpiod_get* functions take an additional parameter that allows to
specify direction and initial value for output.
Simplify the usage of devm_gpiod_get_optional accordingly.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Don't clear the backlight level when we're going into suspend or
blanking. Instead, just temporarily set the level to 0 so we retain
the value when we resume.

Reported-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Tested-by: Stephen Barber <smbarber@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Acked-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

The GPIO subsystem provides dummy GPIO consumer functions if GPIOLIB is
not enabled. Hence drivers that depend on GPIOLIB, but use GPIO consumer
functionality only, can still be compiled if GPIOLIB is not enabled.

Relax the dependency on GPIOLIB if COMPILE_TEST is enabled, where
appropriate.

Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

The platform_device_id is not modified by the driver and core uses it as
const.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>