The various devm_ functions allocate memory that is released when a driver
detaches.  This patch uses these functions for data that is allocated in
the probe function of a platform device and is only freed in the remove
function.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

 - Current implementation tests wrong value for setting
   aat2870_bl->max_current.

 - In the current implementation, we cannot differentiate between 2 cases:

   a) if pdata->max_current is not set , or

   b) pdata->max_current is set to AAT2870_CURRENT_0_45 (which is also 0).

   Fix it by setting AAT2870_CURRENT_0_45 to be 1 and adjust the equation in
   aat2870_brightness() accordingly.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Tested-by: Jin Park <jinyoungp@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight_device_register() returns ERR_PTR() on error.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Jin Park <jinyoungp@nvidia.com>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add backlight driver for AnalogicTech AAT2870.

Signed-off-by: Jin Park <jinyoungp@nvidia.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>