There may be multiple ways of controlling the backlight on a given
machine.  Allow drivers to expose the type of interface they are
providing, making it possible for userspace to make appropriate policy
decisions.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Airlie <airlied@linux.ie>
Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Handle return value, strict_strtoul is declared with attribute
warn_unused_result.
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Acked-by: NRichard Purdie <rpurdie@linux.intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This affects the get/set of the current Ambient Light Zone.  Reading
should return an integer between 1..3 (1 = Daylight, 2 = office, 3 =
dark).  Writing a value between 1..3 forces the backlight controller to
enter the corresponding Ambient Light Zone.  Writing 0 returns to normal
operation.

Fix valid range checking so we don't write invalid values to the
controller, and make sure we subtract 1, since this is what the register
definition (CFGR:BLV) requires.  Otherwise the values written don't work
correctly.
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Acked-by: NRichard Purdie <rpurdie@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I2C drivers can use the clientdata-pointer to point to private data. As I2C
devices are not really unregistered, but merely detached from their driver, it
used to be the drivers obligation to clear this pointer during remove() or a
failed probe(). As a couple of drivers forgot to do this, it was agreed that it
was cleaner if the i2c-core does this clearance when appropriate, as there is
no guarantee for the lifetime of the clientdata-pointer after remove() anyhow.
This feature was added to the core with commit
e4a7b9b0 to fix the faulty drivers.

As there is no need anymore to clear the clientdata-pointer, remove all current
occurrences in the drivers to simplify the code and prevent confusion.
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Acked-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Acked-by: NRichard Purdie <rpurdie@linux.intel.com>
Acked-by: NDmitry Torokhov <dtor@mail.ru>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

Add slab.h to fix part of build.
Add a parameter in backlight_device_register() call to fix part of build.

drivers/video/backlight/adp8860_bl.c:215: error: implicit declaration of function 'kzalloc'
drivers/video/backlight/adp8860_bl.c:215: warning: assignment makes pointer from integer without a cast
drivers/video/backlight/adp8860_bl.c:285: error: implicit declaration of function 'kfree'
drivers/video/backlight/adp8860_bl.c:673: warning: assignment makes pointer from integer without a cast
drivers/video/backlight/adp8860_bl.c:689: error: too few arguments to function 'backlight_device_register'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

The ADP8860 combines a programmable backlight LED charge pump driver with
automatic phototransistor control.
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>