History log of /drivers/video/backlight/pwm_bl.c
Revision Date Author Comments
6728f2b109392484d38ac9e365496ac5fa1071f1 13-Aug-2014 Peter Griffin <peter.griffin@linaro.org> backlight: Remove .owner field for drivers using module_platform_driver

This patch removes the superflous .owner field for drivers which
use the module_platform_driver or platform_driver_register api,
as this is overriden in __platform_driver_register.

Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
937222c4dda495277a8dfbc18bf7e54fe670105c 20-Aug-2014 Lothar Waßmann <LW@KARO-electronics.de> pwm-backlight: Fix bogus request for GPIO#0 when instantiated from DT

commit 257462dbf3ed ("pwm-backlight: switch to gpiod interface")
introduced a regression leading to acquiring a bogus GPIO-0 when
configured from DT without an 'enable-gpios' property.
The driver will happily accept the 0 initialized 'enable_gpio' member
of the struct platform_pwm_backlight_data as valid gpio number, and
request this GPIO as enable pin. In case of multiple driver instances,
the second will fail to register with the error message:
pwm-backlight backlight1.23: failed to request GPIO#0: -16

Fix this by setting enable_gpio in the pdata struct to -EINVAL.

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
ff9c5422d8ebae60bafedf8608ec54d4d87a6bc0 25-Jun-2014 Alexandre Courbot <acourbot@nvidia.com> backlight: pwm-backlight: Use devm_gpiod_get_optional()

Make use of the new devm_gpiod_get_optional() to simplify the probe
code.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
a5d8e2e73c7f1dcee485d55225628317d8d441c0 30-May-2014 Andrzej Hajda <a.hajda@samsung.com> backlight: Remove trivial get_brightness implementations

Since backlight core returns props.brightness in case get_brightness
is not implemented trivial implementations are not needed anymore.

Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
16fc3352ea58b481f879f8d965b98208ccc279c2 19-May-2014 Alexandre Belloni <alexandre.belloni@free-electrons.com> pwm-backlight: retrieve configured PWM period

The PWM core is now able to initialize the PWM period from a lookup
table defined by board files. Use it if available and fallback to the
value supplied in pwm_period_ns.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
257462dbf3ed233de0dc2e489dcc58579535b33f 27-Feb-2014 Alexandre Courbot <acourbot@nvidia.com> pwm-backlight: switch to gpiod interface

Switch to the new gpiod interface, which allows to handle GPIO
properties such as active low transparently and removes a whole bunch of
code.

There are still a couple of users of this driver that rely on passing
the enable GPIO number through platform data, so a fallback mechanism
using a GPIO number is still available to avoid breaking them. It will
be removed once current users have switched to the GPIO lookup tables
provided by the gpiod interface.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
5f33b896246a2d9bdf01352de11d4dab96ba2fc9 29-Apr-2014 Thierry Reding <treding@nvidia.com> pwm-backlight: Disable backlight on shutdown

When a device is shut down, make sure to disable the backlight. If it
stays lit, it gives the impression that the device hasn't turned off.
Furthermore keeping the backlight on may consume power, which is not
what users expect when they shut down a device.

Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
ca7a97add4d4a7b0602b3bd1eff5c89da8636713 01-Dec-2013 Fabio Estevam <fabio.estevam@freescale.com> backlight: pwm_bl: Remove error message upon devm_kzalloc() failure

No need to have a specific OOM message, since there is generic MM out of memory
message in place.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
c512794cada491e008eeca822af7e4ad5db72a56 13-Nov-2013 Jingoo Han <jg1.han@samsung.com> backlight: use dev_get_platdata()

Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly. This is a cosmetic change to
make the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
73d4e2b82b4bb1571b1a7f97012c0db8a0faef42 22-Oct-2013 Thierry Reding <thierry.reding@gmail.com> pwm-backlight: Remove unused variable

I forgot to remove this during earlier cleanup patches and only checked
various builds for errors, not warnings.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
1dea1fd09246ada581a99d0669108eea94b7bfee 09-Oct-2013 Huayi Li <huayi.li@csr.com> pwm_backlight: avoid short blank screen while doing hibernation

Use SIMPLE_DEV_PM_OPS macro will initialize the member "freeze"
and "thaw" of pwm_backlight_pm_ops as below,
.freeze = suspend_fn,
.thaw = resume_fn,
then during the process of making hibernation snapshot, screen
will be blank at the moment of freezing, and then light at the
moment of thawing.
this is not the right user experience for suspending to disk.

so this patch drops freeze and thaw callback, make the LCD is
always lighting before the final shutdown.

Signed-off-by: Huayi Li <huayi.li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
e4bfeda96872bfe6015cd360008b77cd3b981b2b 18-Oct-2013 Thierry Reding <treding@nvidia.com> pwm-backlight: Fix brightness adjustment

Split adjustment of the brightness (by changing the PWM duty cycle) from
the power on sequence. This fixes an issue where the brightness can no
longer be updated once the backlight has been enabled.

Reported-by: Marc Dietrich <marvin24@gmx.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
8f43e18e2769b3b28383903d501b4da29e388aad 22-Sep-2013 Mike Dunn <mikedunn@newsguy.com> pwm-backlight: Allow for non-increasing brightness levels

Currently the driver assumes that the values specified in the
brightness-levels device tree property increase as they are parsed from
left to right. But boards that invert the signal between the PWM output
and the backlight will need to specify decreasing brightness-levels.
This patch removes the assumption that the last element of the array is
the maximum value, and instead searches the array for the maximum value
and uses that in the duty cycle calculation.

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
22ceeee16eb8f0d04de3ef43a5174fb30ec18af9 30-Aug-2013 Thierry Reding <treding@nvidia.com> pwm-backlight: Add power supply support

Backlights require a power supply to work properly. This commit adds a
regulator to power up and power down the backlight.

Signed-off-by: Thierry Reding <treding@nvidia.com>
8265b2e4e62632b01f998095d1bbda4d281629fe 30-Aug-2013 Thierry Reding <treding@nvidia.com> pwm-backlight: Use new enable_gpio field

Make use of the new enable_gpio field and allow it to be set from DT as
well. Now that all legacy users of platform data have been converted to
initialize this field to an invalid value, it is safe to use the field
from the driver.

Signed-off-by: Thierry Reding <treding@nvidia.com>
97c38437115aa0c3fb2d50c488814b503ba529e0 02-Oct-2013 Thierry Reding <treding@nvidia.com> pwm-backlight: Track enable state

Follow up patches will add support for more complex means of powering
the backlight on and off such as using a regulator. To prevent calls to
the regulator API from becoming unbalanced, keep track of the enabled
state internally.

Signed-off-by: Thierry Reding <treding@nvidia.com>
62b744a87c1170b339f993aa3cfb22465974816a 07-Oct-2013 Thierry Reding <treding@nvidia.com> pwm-backlight: Refactor backlight power on/off

In preparation for adding an optional regulator and enable GPIO to the
driver, split the power on and power off sequences into separate
functions to reduce code duplication at the multiple call sites.

Signed-off-by: Thierry Reding <treding@nvidia.com>
668e63c6701d486c68b49ffffc0e5b7de1a2e95c 07-Oct-2013 Thierry Reding <treding@nvidia.com> pwm-backlight: Improve readability

Add more blank lines to increase readability. While at it, remove a
trailing blank line at the end of the file.

Signed-off-by: Thierry Reding <treding@nvidia.com>
c791126b93e800c68557483235321b201c082910 25-Feb-2013 Jingoo Han <jg1.han@samsung.com> pwm_backlight: remove unnecessary ifdefs

When the macro such as SIMPLE_DEV_PM_OPS is used, there is
no need to use '#ifdef CONFIG_PM' to prevent build error. Thus,
this patch removes unnecessary ifdefs.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
e6e3dbf95cb1d434d26acf3f0197c279ba052df4 22-Feb-2013 Jingoo Han <jg1.han@samsung.com> pwm_backlight: use bl_get_data instead of dev_get_drvdata

Use the wrapper function for getting the driver data using
backlight_device instead of using dev_get_drvdata with &bd->dev, so we can
directly pass a struct backlight_device.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
83cfd72669ff708c9d21f214606be785ea8a685c 22-Jan-2013 Peter Ujfalusi <peter.ujfalusi@ti.com> pwm_backlight: Validate dft_brightness in main probe function

Move the dft_brightness validity check from the DT parsing function to the
main probe. In this way we can validate it in case we are booting with or
without DT.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
0132267d659107616eb044777f1b0be55381129a 30-Jan-2013 Alexandre Courbot <acourbot@nvidia.com> pwm-backlight: handle BL_CORE_FBBLANK state

According to include/linux/backlight.h, the fb_blank field is to be
removed and blank status should preferably be set by setting the
BL_CORE_FBBLANK bit of the state field. This patch ensures this
condition is also taken into account when updating the backlight state.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
60ce70285b4d3b933eea15e494a9b35fe85b19b7 17-Sep-2012 Sachin Kamat <sachin.kamat@linaro.org> pwm-backlight: Use devm_pwm_get() instead of pwm_get()

Managed versions of the pwm_get() and pwm_put() functions were recently
added to the PWM framework. They can be used to simplify cleanup in the
error paths and the device removal callback.

Cc: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
9fb978b12f9cc2b4df428764273d96877d0a262d 09-Jul-2012 Alexandre Courbot <acourbot@nvidia.com> pwm_backlight: pass correct brightness to callback

pwm_backlight_update_status calls the notify() and notify_after()
callbacks before and after applying the new PWM settings. However, if
brightness levels are used, the brightness value will be changed from
the index into the levels array to the PWM duty cycle length before
being passed to notify_after(), which results in inconsistent behavior.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
3e3ed6cdc49d758719c148a78c8b04c243ef74d0 16-Dec-2011 Thierry Reding <thierry.reding@avionic-design.de> pwm-backlight: Add rudimentary device tree support

This commit adds very basic support for device tree probing. Currently,
only a PWM and a list of distinct brightness levels can be specified.
Enabling or disabling backlight power via GPIOs is not yet supported.

Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
ce969228fdb54a7e3d7cc1ed27367fd4b9525d74 23-Mar-2012 Julia Lawall <Julia.Lawall@lip6.fr> 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>
e2c17bc6f717a8847df2a867caec6ba4fe85f3fc 11-Jan-2012 Mark Brown <broonie@opensource.wolfsonmicro.com> 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>
81178e021689bf86c328f144aa0f0e1b50f5e94c 11-Jan-2012 Axel Lin <axel.lin@gmail.com> 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>
cc7993f6439b49909a8792660c4d0741fec9d584 26-Aug-2011 Dilan Lee <dilee@nvidia.com> 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>
ef0a5e80f56f6409e957e7117da9551c3d3ff239 23-Mar-2011 Robert Morell <rmorell@nvidia.com> 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>
bb7ca747f8d6243b3943c5b133048652020f4a50 23-Mar-2011 Matthew Garrett <mjg@redhat.com> 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>
fef7764f8bca9d603a8a51dcb522db97739a33c2 11-Nov-2010 Arun Murthy <arun.murthy@stericsson.com> 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>
5a0e3ad6af8660be21ca98a971cd00f331318c05 24-Mar-2010 Tejun Heo <tj@kernel.org> 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>
a19a6ee6cad2b20292a774c2f56ba8039b0fac9c 17-Feb-2010 Matthew Garrett <mjg@redhat.com> 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>
cfc3899fcd0b3b990b29d3d33f75f4edf715e7d1 10-Nov-2009 Ben Dooks <ben@simtec.co.uk> 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>
9905a43b2d563e6f89e4c63c4278ada03f2ebb14 14-Dec-2009 Emese Revfy <re.emese@gmail.com> backlight: Constify struct backlight_ops

Signed-off-by: Emese Revfy <re.emese@gmail.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
82e8b54229fb121946151b82e8ff3c3284bd723f 19-Jun-2009 Marc Zyngier <maz@misterjones.org> 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>
b8cdd877f2cbcc07b5a287b7273a8eaa4c11ad04 10-Feb-2009 Eric Miao <eric.y.miao@gmail.com> 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>
8cd6819842b79953c61250c719f61e01e51dd8cd 05-Aug-2008 Ben Dooks <ben-linux@fluff.org> 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>
14563a4ec450f35c70fbe5f6ac5199e9d5a0edc5 05-Aug-2008 Ben Dooks <ben-linux@fluff.org> 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>
43bda1a6d218744382547a2f8be3240d1c3a151b 01-Jul-2008 Ben Dooks <ben-linux@fluff.org> [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>
3b73125af69f93972625f4b655675f42ca4274eb 22-May-2008 Philipp Zabel <philipp.zabel@gmail.com> [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>
42796d37da6ef4fd851dc6d5d0387baf7e2b0c3c 14-Apr-2008 eric miao <eric.miao@marvell.com> [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>