Commit Graph

18 Commits

Author SHA1 Message Date
Julia Lawall ce969228fd drivers/video/backlight: use devm_ functions
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>
2012-03-23 16:58:33 -07:00
Mark Brown e2c17bc6f7 backlight: convert pwm_bl to dev_pm_ops
Should be no functional changes, mainly a reorganisation to support future
work.

[akpm@linux-foundation.org: fix CONFIG_PM=n build]
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:48 -08:00
Axel Lin 81178e0216 backlight: convert drivers/video/backlight/* to use module_platform_driver()
Convert the drivers in drivers/video/backlight/* to use the
module_platform_driver() macro which makes the code smaller and a bit
simpler.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>	[ep93xx_bl.c]
Cc: Mike Rapoport <mike@compulab.co.il>
Cc: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:48 -08:00
Dilan Lee cc7993f643 backlight: add a callback 'notify_after' for backlight control
We need a callback to do some things after pwm_enable, pwm_disable
and pwm_config.

Signed-off-by: Dilan Lee <dilee@nvidia.com>
Reviewed-by: Robert Morell <rmorell@nvidia.com>
Reviewed-by: Arun Murthy <arun.murthy@stericsson.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-25 16:25:34 -07:00
Robert Morell ef0a5e80f5 pwm_backlight: add check_fb() hook
In systems with multiple framebuffer devices, one of the devices might be
blanked while another is unblanked.  In order for the backlight blanking
logic to know whether to turn off the backlight for a particular
framebuffer's blanking notification, it needs to be able to check if a
given framebuffer device corresponds to the backlight.

This plumbs the check_fb hook from core backlight through the
pwm_backlight helper to allow platform code to plug in a check_fb hook.

Signed-off-by: Robert Morell <rmorell@nvidia.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Arun Murthy <arun.murthy@stericsson.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:00 -07:00
Matthew Garrett bb7ca747f8 backlight: add backlight type
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: Matthew 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:59 -07:00
Arun Murthy fef7764f8b backlight: add low threshold to pwm backlight
The intensity of the backlight can be varied from a range of
max_brightness to zero.  Though most, if not all the pwm based backlight
devices start flickering at lower brightness value.  And also for each
device there exists a brightness value below which the backlight appears
to be turned off though the value is not equal to zero.

If the range of brightness for a device is from zero to max_brightness.  A
graph is plotted for brightness Vs intensity for the pwm based backlight
device has to be a linear graph.

intensity
	  |   /
	  |  /
	  | /
	  |/
	  ---------
	 0	max_brightness

But pratically on measuring the above we note that the intensity of
backlight goes to zero(OFF) when the value in not zero almost nearing to
zero(some x%).  so the graph looks like

intensity
	  |    /
	  |   /
	  |  /
	  |  |
	  ------------
	 0   x	 max_brightness

In order to overcome this drawback knowing this x% i.e nothing but the low
threshold beyond which the backlight is off and will have no effect, the
brightness value is being offset by the low threshold value(retaining the
linearity of the graph).  Now the graph becomes

intensity
	  |     /
	  |    /
	  |   /
	  |  /
	  -------------
	   0	  max_brightness

With this for each and every digit increment in the brightness from zero
there is a change in the intensity of backlight.  Devices having this
behaviour can set the low threshold brightness(lth_brightness) and pass
the same as platform data else can have it as zero.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Arun Murthy <arun.murthy@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-12 07:55:33 -08:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Matthew Garrett a19a6ee6ca backlight: Allow properties to be passed at registration
Values such as max_brightness should be set before backlights are
registered, but the current API doesn't allow that. Add a parameter to
backlight_device_register and update drivers to ensure that they
set this correctly.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2010-03-16 19:47:54 +00:00
Ben Dooks cfc3899fcd backlight: Pass device through notify callback in the pwm driver
Add the device to the notify callback's arguments in the PWM backlight 
driver. This brings the notify callback into line with the other 
callbacks defined by this driver.

Signed-off-by: Ben Dooks <ben@simtec.co.uk>
Signed-off-by: Simtec Linux Team <linux@simtec.co.uk>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2009-12-17 11:46:01 +00:00
Emese Revfy 9905a43b2d backlight: Constify struct backlight_ops
Signed-off-by: Emese Revfy <re.emese@gmail.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2009-12-16 11:33:46 +00:00
Marc Zyngier 82e8b54229 backlight: fix pwm_bl.c to notify platform code when suspending
When suspending, pwm-bl sets duty cycle to 0, and shuts down the pwm
device.

This patch ensure that the platform code is called before that
(through the notify callback_, leaving a chance for the platform code
to configure GPIOs (shutting off the backlight, for example), much like
it is done during normal operations.

Signed-off-by: Marc Zyngier <maz@misterjones.org>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
2009-07-03 14:22:41 +08:00
Eric Miao b8cdd877f2 backlight: fix pwm_bl.c when multiple PWM backlights exist
When multiple PWMs are used as backlights, the current code uses
pdev->name as the backlight name when registering, which will be
conflicting, use dev_name() instead.

Signed-off-by: Peter Edwards <sweetlilmre@gmail.com>
Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2009-04-06 16:06:55 +01:00
Ben Dooks 8cd6819842 backlight: add MODULE_ALIAS() to pwm_backlight driver
Add the missing MODULE_ALIAS() to the pwm_backlight driver.

Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-05 14:33:48 -07:00
Ben Dooks 14563a4ec4 backlight: add more information output to pwm_backlight
Make the error paths in the pwm_backlight driver more informative in the
probe path, especially for the times that it finds an error.

Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-05 14:33:48 -07:00
Ben Dooks 43bda1a6d2 [ARM] 5141/1: PWM: pwm_request() should return an PTR_ERR() instead of NULL.
Make the return of pwm_request() be more informative than just
being NULL on error by using PTR_ERR() to respond with an
approriate error.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-07-03 13:25:07 +01:00
Philipp Zabel 3b73125af6 [ARM] 5044/1: pwm_bl: add init/notify/exit callbacks
This allows platform code to manipulate GPIOs and brightness level as
needed.

Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-07-03 13:25:05 +01:00
eric miao 42796d37da [ARM] pxa: add generic PWM backlight driver
Patch mostly from Eric Miao, with minor edits by rmk to convert
Eric's driver to a generic PWM-based backlight driver.

Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-07-03 13:25:00 +01:00