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path: root/drivers/video/backlight/pwm_bl.c
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2014-08-20pwm-backlight: Fix bogus request for GPIO#0 when instantiated from DTLothar Waßmann
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>
2014-07-18backlight: pwm-backlight: Use devm_gpiod_get_optional()Alexandre Courbot
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>
2014-06-23backlight: Remove trivial get_brightness implementationsAndrzej Hajda
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>
2014-05-21pwm-backlight: retrieve configured PWM periodAlexandre Belloni
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>
2014-05-07pwm-backlight: switch to gpiod interfaceAlexandre Courbot
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>
2014-05-02pwm-backlight: Disable backlight on shutdownThierry Reding
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>
2013-12-17backlight: pwm_bl: Remove error message upon devm_kzalloc() failureFabio Estevam
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>
2013-11-16Merge tag 'pwm/for-3.13-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm Pull pwm changes from Thierry Reding: "Mostly bug fixes and clean up. There is a new driver, which is actually moving a custom PWM driver from drivers/misc. The majority of the patches are enhancements to the device tree support in the pwm-backlight driver. Backlights can now additionally be powered using a regulator and enabled using a GPIO in addition to just the PWM input" * tag 'pwm/for-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (30 commits) Documentation/pwm: Update supported SoC name for pwm-samsung pwm: samsung: Fix kernel warning while unexporting a channel MAINTAINERS: Move PWM subsystem tree to kernel.org Documentation/pwm: Fix trivial typos pwm-backlight: Remove unused variable pwm_backlight: avoid short blank screen while doing hibernation pwm-backlight: Fix brightness adjustment pwm: add ep93xx PWM support pwm-backlight: Allow for non-increasing brightness levels pwm-backlight: Add power supply support pwm-backlight: Use new enable_gpio field unicore32: Initialize PWM backlight enable_gpio field ARM: shmobile: Initialize PWM backlight enable_gpio field ARM: SAMSUNG: Initialize PWM backlight enable_gpio field ARM: pxa: Initialize PWM backlight enable_gpio field ARM: OMAP: Initialize PWM backlight enable_gpio field pwm-backlight: Add optional enable GPIO pwm-backlight: Track enable state pwm-backlight: Refactor backlight power on/off pwm-backlight: Improve readability ...
2013-11-13backlight: use dev_get_platdata()Jingoo Han
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>
2013-10-22pwm-backlight: Remove unused variableThierry Reding
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>
2013-10-22pwm_backlight: avoid short blank screen while doing hibernationHuayi Li
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>
2013-10-18pwm-backlight: Fix brightness adjustmentThierry Reding
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>
2013-10-16pwm-backlight: Allow for non-increasing brightness levelsMike Dunn
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>
2013-10-16pwm-backlight: Add power supply supportThierry Reding
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>
2013-10-16pwm-backlight: Use new enable_gpio fieldThierry Reding
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>
2013-10-16pwm-backlight: Track enable stateThierry Reding
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>
2013-10-16pwm-backlight: Refactor backlight power on/offThierry Reding
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>
2013-10-16pwm-backlight: Improve readabilityThierry Reding
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>
2013-03-08pwm_backlight: remove unnecessary ifdefsJingoo Han
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>
2013-02-26Merge tag 'for-3.9-rc1' of git://gitorious.org/linux-pwm/linux-pwmLinus Torvalds
Pull PWM changes from Thierry Reding: "A new driver has been added to support the PWM mode of the timer counter blocks found on Atmel AT91 SoCs. The VT8500 driver now supports changing the PWM signal polarity and the TI drivers (EHRPWM and ECAP) gained suspend and resume functionality. User drivers can now query the core for whether access to a PWM device will sleep (if the PWM chip is on a slow bus such as I2C or SPI). The pwm-backlight driver now handles the backlight BL_CORE_FBBLANK state in addition to the FB layer's blanking states. To round things off, a few fixes and cleanups are also included" * tag 'for-3.9-rc1' of git://gitorious.org/linux-pwm/linux-pwm: pwm: twl: Use to_twl() instead of container_of() pwm: tegra: assume CONFIG_OF pwm_backlight: Validate dft_brightness in main probe function pwm: Export pwm_{set,get}_chip_data() pwm: Make Kconfig entries more consistent pwm: Add can_sleep property to drivers pwm: Add pwm_can_sleep() as exported API to users pwm-backlight: handle BL_CORE_FBBLANK state pwm: pwm-tiecap: Low power sleep support pwm: pwm-tiehrpwm: Low power sleep support pwm: pwm-tiehrpwm: Update the clock handling of pwm-tiehrpwm driver pwm: vt8500: Add polarity support pwm: vt8500: Register write busy test performed incorrectly pwm: atmel: add Timer Counter Block PWM driver
2013-02-21pwm_backlight: use bl_get_data instead of dev_get_drvdataJingoo Han
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>
2013-01-31pwm_backlight: Validate dft_brightness in main probe functionPeter Ujfalusi
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>
2013-01-30pwm-backlight: handle BL_CORE_FBBLANK stateAlexandre Courbot
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>
2012-10-05pwm-backlight: Use devm_pwm_get() instead of pwm_get()Sachin Kamat
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>
2012-07-23pwm_backlight: pass correct brightness to callbackAlexandre Courbot
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>
2012-07-23pwm-backlight: Add rudimentary device tree supportThierry Reding
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>
2012-03-23drivers/video/backlight: use devm_ functionsJulia Lawall
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>
2012-01-10backlight: convert pwm_bl to dev_pm_opsMark Brown
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>
2012-01-10backlight: convert drivers/video/backlight/* to use module_platform_driver()Axel Lin
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>
2011-08-25backlight: add a callback 'notify_after' for backlight controlDilan Lee
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>
2011-03-22pwm_backlight: add check_fb() hookRobert Morell
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>
2011-03-22backlight: add backlight typeMatthew Garrett
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>
2010-11-12backlight: add low threshold to pwm backlightArun Murthy
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>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
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>
2010-03-16backlight: Allow properties to be passed at registrationMatthew Garrett
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>
2009-12-17backlight: Pass device through notify callback in the pwm driverBen Dooks
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>
2009-12-16backlight: Constify struct backlight_opsEmese Revfy
Signed-off-by: Emese Revfy <re.emese@gmail.com> Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2009-07-03backlight: fix pwm_bl.c to notify platform code when suspendingMarc Zyngier
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>
2009-04-06backlight: fix pwm_bl.c when multiple PWM backlights existEric Miao
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>
2008-08-05backlight: add MODULE_ALIAS() to pwm_backlight driverBen Dooks
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>
2008-08-05backlight: add more information output to pwm_backlightBen Dooks
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>
2008-07-03[ARM] 5141/1: PWM: pwm_request() should return an PTR_ERR() instead of NULL.Ben Dooks
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[ARM] 5044/1: pwm_bl: add init/notify/exit callbacksPhilipp Zabel
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[ARM] pxa: add generic PWM backlight drivereric miao
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>