Commit Graph

734 Commits

Author SHA1 Message Date
Uwe Kleine-König
51e89f1c0a backlight: lm3630a: Fix return code of .update_status() callback
[ Upstream commit b9481a667a ]

According to <linux/backlight.h> .update_status() is supposed to
return 0 on success and a negative error code otherwise. Adapt
lm3630a_bank_a_update_status() and lm3630a_bank_b_update_status() to
actually do it.

While touching that also add the error code to the failure message.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-16 11:26:58 +09:00
dinghao.liu@zju.edu.cn
5cf3bdc57a backlight: sky81452-backlight: Fix refcount imbalance on error
[ Upstream commit b7a4f80bc3 ]

When of_property_read_u32_array() returns an error code, a
pairing refcount decrement is needed to keep np's refcount
balanced.

Fixes: f705806c9f ("backlight: Add support Skyworks SKY81452 backlight driver")
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-16 09:37:55 +09:00
Jon Hunter
766fa3cfa2 backlight: lp855x: Ensure regulators are disabled on probe failure
[ Upstream commit d8207c155a ]

If probing the LP885x backlight fails after the regulators have been
enabled, then the following warning is seen when releasing the
regulators ...

 WARNING: CPU: 1 PID: 289 at drivers/regulator/core.c:2051 _regulator_put.part.28+0x158/0x160
 Modules linked in: tegra_xudc lp855x_bl(+) host1x pwm_tegra ip_tables x_tables ipv6 nf_defrag_ipv6
 CPU: 1 PID: 289 Comm: systemd-udevd Not tainted 5.6.0-rc2-next-20200224 #1
 Hardware name: NVIDIA Jetson TX1 Developer Kit (DT)

 ...

 Call trace:
  _regulator_put.part.28+0x158/0x160
  regulator_put+0x34/0x50
  devm_regulator_release+0x10/0x18
  release_nodes+0x12c/0x230
  devres_release_all+0x34/0x50
  really_probe+0x1c0/0x370
  driver_probe_device+0x58/0x100
  device_driver_attach+0x6c/0x78
  __driver_attach+0xb0/0xf0
  bus_for_each_dev+0x68/0xc8
  driver_attach+0x20/0x28
  bus_add_driver+0x160/0x1f0
  driver_register+0x60/0x110
  i2c_register_driver+0x40/0x80
  lp855x_driver_init+0x20/0x1000 [lp855x_bl]
  do_one_initcall+0x58/0x1a0
  do_init_module+0x54/0x1d0
  load_module+0x1d80/0x21c8
  __do_sys_finit_module+0xe8/0x100
  __arm64_sys_finit_module+0x18/0x20
  el0_svc_common.constprop.3+0xb0/0x168
  do_el0_svc+0x20/0x98
  el0_sync_handler+0xf4/0x1b0
  el0_sync+0x140/0x180

Fix this by ensuring that the regulators are disabled, if enabled, on
probe failure.

Finally, ensure that the vddio regulator is disabled in the driver
remove handler.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-16 08:18:08 +09:00
Brian Masney
9aebdfa28f backlight: lm3630a: Return 0 on success in update_status functions
[ Upstream commit d3f48ec095 ]

lm3630a_bank_a_update_status() and lm3630a_bank_b_update_status()
both return the brightness value if the brightness was successfully
updated. Writing to these attributes via sysfs would cause a 'Bad
address' error to be returned. These functions should return 0 on
success, so let's change it to correct that error.

Fixes: 28e64a68a2 ("backlight: lm3630: apply chip revision")
Signed-off-by: Brian Masney <masneyb@onstation.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-15 16:45:23 +09:00
Nathan Chancellor
26ebab9d86 backlight: lm3639: Unconditionally call led_classdev_unregister
[ Upstream commit 7cea645ae9 ]

Clang warns that the address of a pointer will always evaluated as true
in a boolean context.

drivers/video/backlight/lm3639_bl.c:403:14: warning: address of
'pchip->cdev_torch' will always evaluate to 'true'
[-Wpointer-bool-conversion]
        if (&pchip->cdev_torch)
        ~~   ~~~~~~~^~~~~~~~~~
drivers/video/backlight/lm3639_bl.c:405:14: warning: address of
'pchip->cdev_flash' will always evaluate to 'true'
[-Wpointer-bool-conversion]
        if (&pchip->cdev_flash)
        ~~   ~~~~~~~^~~~~~~~~~
2 warnings generated.

These statements have been present since 2012, introduced by
commit 0f59858d51 ("backlight: add new lm3639 backlight
driver"). Given that they have been called unconditionally since
then presumably without any issues, removing the always true if
statements to fix the warnings without any real world changes.

Link: https://github.com/ClangBuiltLinux/linux/issues/119
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-15 15:12:27 +09:00
Enric Balletbo i Serra
87d5bb139c pwm-backlight: Enable/disable the PWM before/after LCD enable toggle.
commit 5fb5caee92 upstream.

Before this patch the enable signal was set before the PWM signal and
vice-versa on power off. This sequence is wrong, at least, it is on
the different panels datasheets that I checked, so I inverted the sequence
to follow the specs.

For reference the following panels have the mentioned sequence:
  - N133HSE-EA1 (Innolux)
  - N116BGE (Innolux)
  - N156BGE-L21 (Innolux)
  - B101EAN0 (Auo)
  - B101AW03 (Auo)
  - LTN101NT05 (Samsung)
  - CLAA101WA01A (Chunghwa)

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-15 12:07:34 +09:00
Johan Hovold
099fae46d8 backlight: tps65217_bl: Fix Device Tree node lookup
commit 2b12dfa124 upstream.

Fix child-node lookup during probe, which ended up searching the whole
device tree depth-first starting at the parent rather than just matching
on its children.

This would only cause trouble if the child node is missing while there
is an unrelated node named "backlight" elsewhere in the tree.

Cc: stable <stable@vger.kernel.org>     # 3.7
Fixes: eebfdc17cc ("backlight: Add TPS65217 WLED driver")
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03 11:23:14 +02:00
Johan Hovold
a89e596f12 backlight: max8925_bl: Fix Device Tree node lookup
commit d1cc0ec3da upstream.

Fix child-node lookup during probe, which ended up searching the whole
device tree depth-first starting at the parent rather than just matching
on its children.

To make things worse, the parent mfd node was also prematurely freed,
while the child backlight node was leaked.

Cc: stable <stable@vger.kernel.org>     # 3.9
Fixes: 47ec340cb8 ("mfd: max8925: Support dt for backlight")
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03 11:23:14 +02:00
Johan Hovold
47f764c65c backlight: as3711_bl: Fix Device Tree node lookup
commit 4a9c8bb2ac upstream.

Fix child-node lookup during probe, which ended up searching the whole
device tree depth-first starting at the parent rather than just matching
on its children.

To make things worse, the parent mfd node was also prematurely freed.

Cc: stable <stable@vger.kernel.org>     # 3.10
Fixes: 59eb2b5e57 ("drivers/video/backlight/as3711_bl.c: add OF support")
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03 11:23:14 +02:00
Sudip Mukherjee
6625fd2adc backlight: Report error on failure
[ Upstream commit 7e715c2d9c ]

It is possible to update the backlight power and the brightness using
the sysfs and on writing it either returns the count or if the callback
function does not exist then returns the error code 'ENXIO'.

We have a situation where the userspace client is writing to the sysfs
to update the power and since the callback function exists the client
receives the return value as count and considers the operation to be
successful. That is correct as the write to the sysfs was successful.
But there is no way to know if the actual operation was done or not.

backlight_update_status() returns the error code if it fails. Pass that
to the userspace client who is trying to update the power so that the
client knows that the operation failed.

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13 19:48:13 +02:00
Robert Jarzmik
8612220ec4 backlight: tdo24m: Fix the SPI CS between transfers
[ Upstream commit 2023b0524a ]

Currently the LCD display (TD035S) on the cm-x300 platform is broken and
remains blank.

The TD0245S specification requires that the chipselect is toggled
between commands sent to the panel. This was also the purpose of the
former patch of commit f64dcac0b1 ("backlight: tdo24m: ensure chip
select changes between transfers").

Unfortunately, the "cs_change" field of a SPI transfer is
misleading. Its true meaning is that for a SPI message holding multiple
transfers, the chip select is toggled between each transfer, but for the
last transfer it remains asserted.

In this driver, all the SPI messages contain exactly one transfer, which
means that each transfer is the last of its message, and as a
consequence the chip select is never toggled.

Actually, there was a second bug hidding the first one, hence the
problem was not seen until v4.6. This problem was fixed by commit
a52db659c7 ("spi: pxa2xx: Fix cs_change management") for PXA based
boards.

This fix makes the TD035S work again on a cm-x300 board. The same
applies to other PXA boards, ie. corgi and tosa.

Fixes: a52db659c7 ("spi: pxa2xx: Fix cs_change management")
Reported-by: Andrea Adami <andrea.adami@gmail.com>
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13 19:48:11 +02:00
Derek Basehore
291c7e488f backlight: pwm_bl: Fix overflow condition
[ Upstream commit 5d0c49aceb ]

This fixes an overflow condition that can happen with high max
brightness and period values in compute_duty_cycle. This fixes it by
using a 64 bit variable for computing the duty cycle.

Signed-off-by: Derek Basehore <dbasehore@chromium.org>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-25 14:23:43 +01:00
Alexey Khoroshilov
473286bdd5 backlight: adp5520: Fix error handling in adp5520_bl_probe()
[ Upstream commit 0eb3fba8c6 ]

If adp5520_bl_setup() fails, sysfs group left unremoved.

By the way, fix overcomplicated assignement of error code.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-21 09:23:25 +01:00
Uwe Kleine-König
6aaf9ba9bd backlight: lcd: Fix race condition during register
[ Upstream commit cc21942bce ]

Once device_register is called for a device its attributes might be
accessed. As the callbacks of a lcd device's attributes make use of the
lcd_ops, the respective member must be setup before calling
device_register.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-21 09:23:25 +01:00
Maxime Ripard
0c9501f823 backlight: pwm_bl: Handle gpio that can sleep
Some backlight GPIOs might be connected to some i2c based expanders whose
access might sleep.

Since it's not in any critical path, use the cansleep variant of the GPIO
API.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2016-10-06 09:27:26 +01:00
Markus Elfring
358791033f backlight-tosa: Delete unnecessary assignment for the field "owner"
The field "owner" is set by the core.
Thus delete an unneeded initialisation.

Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2016-10-06 09:27:25 +01:00
Brian Norris
6025530738 backlight: lp855x: Add enable regulator
The LP8556 datasheet describes an EN/VDDIO input, which serves "both as
a chip enable and as a power supply reference for PWM, SDA, and SCL
inputs." The LP8556 that I'm testing doesn't respond properly if I try
to talk I2C to it too quickly after enabling VDDIO, and the LP8555
datasheet mentions a t_RESPONSE delay of up to 1 millisecond.

Support this EN/VDDIO by adding a regulator property to the binding;
enabling this regulator at probe time; and sleeping for 1 to 2ms, if the
EN/VDDIO regulator was provided.

Signed-off-by: Brian Norris <briannorris@chromium.org>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Milo Kim <milo.kim@ti.com>
Reviewed-by: Stephen Barber <smbarber@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2016-06-29 10:06:21 +01:00
Linus Torvalds
ecc5fbd5ef Merge tag 'pwm/for-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm
Pull pwm updates from Thierry Reding:
 "This set of changes introduces an atomic API to the PWM subsystem.
  This is influenced by the DRM atomic API that was introduced a while
  back, though it is obviously a lot simpler.  The fundamental idea
  remains the same, though: drivers provide a single callback to
  implement the atomic configuration of a PWM channel.

  As a side-effect the PWM subsystem gains the ability for initial state
  retrieval, so that the logical state mirrors that of the hardware.
  Many use-cases don't care about this, but for others it is essential.

  These new features require changes in all users, which these patches
  take care of.  The core is transitioned to use the atomic callback if
  available and provides a fallback mechanism for other drivers.

  Changes to transition users and drivers to the atomic API are
  postponed to v4.8"

* tag 'pwm/for-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (30 commits)
  pwm: Add information about polarity, duty cycle and period to debugfs
  pwm: Switch to the atomic API
  pwm: Update documentation
  pwm: Add core infrastructure to allow atomic updates
  pwm: Add hardware readout infrastructure
  pwm: Move the enabled/disabled info into pwm_state
  pwm: Introduce the pwm_state concept
  pwm: Keep PWM state in sync with hardware state
  ARM: Explicitly apply PWM config extracted from pwm_args
  drm: i915: Explicitly apply PWM config extracted from pwm_args
  input: misc: pwm-beeper: Explicitly apply PWM config extracted from pwm_args
  input: misc: max8997: Explicitly apply PWM config extracted from pwm_args
  backlight: lm3630a: explicitly apply PWM config extracted from pwm_args
  backlight: lp855x: Explicitly apply PWM config extracted from pwm_args
  backlight: lp8788: Explicitly apply PWM config extracted from pwm_args
  backlight: pwm_bl: Use pwm_get_args() where appropriate
  fbdev: ssd1307fb: Use pwm_get_args() where appropriate
  regulator: pwm: Use pwm_get_args() where appropriate
  leds: pwm: Use pwm_get_args() where appropriate
  input: misc: max77693: Use pwm_get_args() where appropriate
  ...
2016-05-25 10:40:15 -07:00
Boris Brezillon
7ff666bc4b backlight: lm3630a: explicitly apply PWM config extracted from pwm_args
Call pwm_apply_args() just after requesting the PWM device so that the
polarity and period are initialized according to the information
provided in pwm_args.

This is an intermediate state, and pwm_apply_args() should be dropped as
soon as the atomic PWM infrastructure is in place and the driver makes
use of it.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-05-17 14:45:05 +02:00
Boris Brezillon
6fbab835a9 backlight: lp855x: Explicitly apply PWM config extracted from pwm_args
Call pwm_apply_args() just after requesting the PWM device so that the
polarity and period are initialized according to the information
provided in pwm_args.

This is an intermediate state, and pwm_apply_args() should be dropped as
soon as the atomic PWM infrastructure is in place and the driver makes
use of it.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-05-17 14:45:05 +02:00
Boris Brezillon
058be4d6c6 backlight: lp8788: Explicitly apply PWM config extracted from pwm_args
Call pwm_apply_args() just after requesting the PWM device so that the
polarity and period are initialized according to the information
provided in pwm_args.

This is an intermediate state, and pwm_apply_args() should be dropped as
soon as the atomic PWM infrastructure is in place and the driver makes
use of it.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-05-17 14:45:04 +02:00
Boris Brezillon
6cb9644db7 backlight: pwm_bl: Use pwm_get_args() where appropriate
The PWM framework has clarified the concept of reference PWM config (the
platform dependent config retrieved from the DT or the PWM lookup table)
and real PWM state.

Use pwm_get_args() when the PWM user wants to retrieve this reference
config and not the current state.

This is part of the rework allowing the PWM framework to support
hardware readout and expose real PWM state even when the PWM has just
been requested (before the user calls pwm_config/enable/disable()).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-05-17 14:45:03 +02:00
Boris BREZILLON
4ff66efd59 backlight: lm3630a_bl: Stop messing with the pwm->period field
pwm->period field is not supposed to be changed by PWM users. The only
ones authorized to change it are the PWM core and PWM drivers.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-05-17 14:44:58 +02:00
Boris BREZILLON
7f044b09b6 backlight: pwm_bl: Remove useless call to pwm_set_period()
The PWM period will be set when calling pwm_config. Remove this useless
call to pwm_set_period(), which might mess up the internal PWM state.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-05-17 14:44:58 +02:00
Aaron Lu
01c3664de6 video / backlight: remove the backlight_device_registered API
Since we will need the backlight_device_get_by_type API, we can use it
instead of the backlight_device_registered API whenever necessary so
remove the backlight_device_registered API.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-05-04 23:41:14 +02:00
Aaron Lu
f6a4790a54 video / backlight: add two APIs for drivers to use
It is useful to get the backlight device's pointer and use it to set
backlight in some cases(the following patch will make use of it) so add
the two APIs and export them.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-05-04 23:41:14 +02:00
Vladimir Zapolskiy
60d613d6ae backlight: pwm_bl: Free PWM requested by legacy API on error path
If pwm is requested by legacy pwm_request() and if the following
backlight_device_register() call fails, add pwm_free() clean-up.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2016-01-11 10:45:24 +00:00
Arnd Bergmann
02f22c004f backlight: adp8860: Fix another uninitialized variable use
A recent patch I did fixed two potential uses of uninitialized
variables in the adp8870 and adp8860 drivers. Unfortunately,
I missed another one:

drivers/video/backlight/adp8860_bl.c: In function 'adp8860_bl_ambient_light_level_show':
drivers/video/backlight/adp8860_bl.c:570:11: warning: 'reg_val' may be used uninitialized in this function

This does the same change as before in one additional function,
and also changes the check for the return value in a way that
avoids another false positive warning with a similar message.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 6be3a5a9cd91 ("backlight: adp88x0: Fix uninitialized variable use")
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2016-01-11 07:58:43 +00:00
Stefan Agner
2f4647a149 backlight: gpio-backlight: Use default-on on GPIO request
There are situations where the backlight should be on at boot time
(e.g. if the boot loader already turned the display on). The DT
bindings specify the "default-on" property for that purpose.
Currently, the initial state of the GPIO at request time is always
set to logical off (high or low depending on whether it is an
active high or low GPIO). Since the GPIO is requested as an output,
the GPIO will be driven low for a short period of time, which leads
to a flickering display in the above use-case.

Initialize the GPIO depending on the default-on property to be
logical on or off.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2016-01-11 07:58:35 +00:00
Philipp Zabel
8777078015 backlight: pwm_bl: Fix broken PWM backlight for non-dt platforms
Commit ee65ad0e2a9e ("backlight: pwm_bl: Avoid backlight flicker when
probed from DT") tries to dereference the device of_node pointer
unconditionally, causing a NULL pointer dereference on non-dt platforms.
Fix it by replacing the phandle variable with a node variable and
by checking that for NULL before dereferencing it.

Reported-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2016-01-11 06:36:43 +00:00
Enric Balletbo i Serra
fcf13f0b9e backlight: tps65217_bl: Add MODULE_DEVICE_TABLE
The device table is required to load modules based on modaliases.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2016-01-11 06:36:35 +00:00
Philipp Zabel
3698d7e7d2 backlight: pwm_bl: Avoid backlight flicker when probed from DT
If the driver is probed from the device tree, and there is a phandle
property set on it, and the enable GPIO is already configured as output,
and the backlight is currently disabled, keep it disabled.
If all these conditions are met, assume there will be some other driver
that can enable the backlight at the appropriate time.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2016-01-11 05:56:22 +00:00
Arnd Bergmann
86c68e2fb3 backlight: adp88x0: Fix uninitialized variable use
gcc correctly warns about both the adp8860 and adp8870 backlight
drivers using an uninitialized variable in their error handling
path:

drivers/video/backlight/adp8870_bl.c: In function 'adp8870_bl_ambient_light_zone_store':
drivers/video/backlight/adp8870_bl.c:811:11: warning: 'reg_val' may be used uninitialized in this function

This changes the code to only write back the data if it was
correctly read to start with.

As a side-note, the drivers are mostly identical, so I think they
should really be merged into one file to avoid having to fix every
bug twice.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2016-01-11 05:56:12 +00:00
Linus Torvalds
5bc23a0cde Merge tag 'backlight-for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight
Pull backlight updates from Lee Jones:
 "New Device Support
   - None

  New Functionality:
   - None

  Core Frameworks:
   - Reject legacy PWM request for device defined in DT

  Fix-ups:
   - Remove unnecessary MODULE_ALIAS(); adp8860_bl, adp8870_bl
   - Simplify code: pm8941-wled
   - Supply default-brightness logic; pm8941-wled

  Bug Fixes:
   - Clean up OF node; 88pm860x_bl
   - Ensure struct is zeroed; lp855x_bl"

* tag 'backlight-for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: pm8941-wled: Add default-brightness property
  backlight: pm8941-wled: Fix ptr_ret.cocci warnings
  backlight: pwm: Reject legacy PWM request for device defined in DT
  backlight: 88pm860x_bl: Add missing of_node_put
  backlight: adp8870: Remove unnecessary MODULE_ALIAS()
  backlight: adp8860: Remove unnecessary MODULE_ALIAS()
  backlight: lp855x: Make sure props struct is zeroed
2015-11-06 10:53:48 -08:00
Bjorn Andersson
9d6c243502 backlight: pm8941-wled: Add default-brightness property
Default the brightness to 2048 and add possibility to override this in
device tree.

Suggested-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-10-30 18:47:51 +00:00
Andrew F. Davis
3821a065f5 spi: Drop owner assignment from spi_drivers
An spi_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-28 10:30:17 +09:00
kbuild test robot
fc18111b89 backlight: pm8941-wled: Fix ptr_ret.cocci warnings
drivers/video/backlight/pm8941-wled.c:404:1-3: WARNING: PTR_ERR_OR_ZERO can be used

 Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR

Generated by: scripts/coccinelle/api/ptr_ret.cocci

Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-10-27 09:00:43 +00:00
Vladimir Zapolskiy
dc881123aa backlight: pwm: Reject legacy PWM request for device defined in DT
Platform PWM backlight data provided by board's device tree should be
complete enough to successfully request a pwm device using pwm_get()
API. This change fixes a bug, when an arbitrary (first found) PWM is
connected to a "pwm-backlight" compatible device, when explicit PWM
device reference is not given.

Documentation/devicetree/bindings/video/backlight/pwm-backlight.txt
already describes "pwms" as a required property, instead of blind
selection of a potentially wrong PWM reject legacy PWM device
registration request, leave legacy API only for non-dt cases.

Based on initial implementation done by Dmitry Eremin-Solenikov.

Reported-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-10-15 12:06:28 +01:00
Julia Lawall
f85de2d9e2 backlight: 88pm860x_bl: Add missing of_node_put
for_each_child_of_node performs an of_node_get on each iteration, so
a break out of the loop requires an of_node_put.

The semantic patch that fixes this problem is as follows
(http://coccinelle.lip6.fr):

// <smpl>
@@
expression root,e;
local idexpression child;
iterator name for_each_child_of_node;
@@

 for_each_child_of_node(root, child) {
   ... when != of_node_put(child)
       when != e = child
+  of_node_put(child);
?  break;
   ...
}
... when != child
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-10-15 12:06:21 +01:00
Javier Martinez Canillas
7111c6c672 backlight: adp8870: Remove unnecessary MODULE_ALIAS()
The driver has a I2C device id table that is used to create the modaliases
and also "adp8870-backlight" is not a supported I2C id, so it's never used.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-10-05 13:48:14 +01:00
Javier Martinez Canillas
da601ebc70 backlight: adp8860: Remove unnecessary MODULE_ALIAS()
The driver has a I2C device id table that is used to create the modaliases
and also "adp8860-backlight" is not a supported I2C id, so it's never used.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-10-05 13:48:13 +01:00
Werner Johansson
9f7898f3ca backlight: lp855x: Make sure props struct is zeroed
The driver occasionally got stuck in suspend mode or other strange
states as those parts of the props struct were never initialized.

Signed-off-by: Werner Johansson <werner.johansson@sonymobile.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Acked-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-10-05 13:47:42 +01:00
Javier Martinez Canillas
13d20b3b61 backlight: tosa: Export I2C module alias information
The I2C core always reports the MODALIAS uevent as "i2c:<modalias>"
regardless of the mechanism that was used to register the device
(i.e: OF or board code) and the table that is used later to match
the driver with the device (i.e: I2C id table or OF match table).

So drivers needs to export the I2C id table and this be built into
the module or udev won't have the necessary information to autoload
the needed driver module when the device is added.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-08-25 08:44:12 +01:00
Markus Elfring
85463d8ed1 backlight: lp8788_bl: Delete a check before backlight_device_unregister()
The backlight_device_unregister() function tests whether its argument
is NULL and then returns immediately. Thus the test around the call is
not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-08-25 08:43:40 +01:00
Axel Lin
047ffbb271 backlight: sky81452: Remove unneeded use of IS_ERR_VALUE() macro
IS_ERR_VALUE() makes sense only *if* there could be valid values in
negative error range.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-08-25 08:43:21 +01:00
Bjorn Andersson
7ddbc2423c backlight: pm8941-wled: Move PM8941 WLED driver to backlight
The Qualcomm PM8941 WLED block is used for backlight and should therefor
be in the backlight framework and not in the LED framework. This moves
the driver and adapts to the backlight api instead.

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Tested-by: Rob Clark <robdclark@gmail.com>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-08-25 08:41:56 +01:00
Milo Kim
fe009175ae backlight: lp855x: Use private data for regulator control
LP855x backlight device can be enabled by external VDD input. The
'supply' data is used for this purpose. It's kind of private data
which runs internally, so there is no reason to expose to the
platform data.

And devm_regulator_get() is moved from _parse_dt() to _probe().
Regulator consumer(lp855x) can control regulator not only from DT
but also from platform data configuration in a source file such
like board-*.c.

Signed-off-by: Milo Kim <milo.kim@ti.com>
Acked-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-08-25 08:40:44 +01:00
Linus Torvalds
d59b92f93d Merge tag 'backlight-for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight
Pull backlight updates from Lee Jones:
 "Changes to existing drivers:

   - supply MODULE_DEVICE_TABLE() to ensure probing
   - constify struct; da9052_bl
   - enable compile test; lcd_l4f00242t03, lcd_lms283fg05, backlight_gpio
   - suspend/resume bugfix; lp855x_bl
   - devm_gpiod_get_optional() API fixup; pwm_bl
   - error handling fixup; backlight"

* tag 'backlight-for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: Change the return type of backlight_update_status() to int
  backlight: pwm_bl: Simplify usage of devm_gpiod_get_optional
  backlight: lp855x: Don't clear level on suspend/blank
  backlight: Allow compile test of GPIO consumers if !GPIOLIB
  video: backlight: da9052: Constify platform_device_id
  gpio-backlight: Discover driver during boot time
2015-06-24 18:57:00 -07:00
Axel Lin
cdaefccefa backlight: pwm_bl: Simplify usage of devm_gpiod_get_optional
Since 39b2bbe3d7 (gpio: add flags argument to gpiod_get*() functions),
the gpiod_get* functions take an additional parameter that allows to
specify direction and initial value for output.
Simplify the usage of devm_gpiod_get_optional accordingly.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-06-23 15:47:34 +01:00
Sean Paul
61c1c6147f backlight: lp855x: Don't clear level on suspend/blank
Don't clear the backlight level when we're going into suspend or
blanking. Instead, just temporarily set the level to 0 so we retain
the value when we resume.

Reported-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Tested-by: Stephen Barber <smbarber@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Acked-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-06-23 15:47:33 +01:00