Commit Graph

907 Commits

Author SHA1 Message Date
Marijn Suijten
f8f3c1720d backlight: qcom-wled: Respect enabled-strings in set_brightness
[ Upstream commit ec961cf324 ]

The hardware is capable of controlling any non-contiguous sequence of
LEDs specified in the DT using qcom,enabled-strings as u32
array, and this also follows from the DT-bindings documentation.  The
numbers specified in this array represent indices of the LED strings
that are to be enabled and disabled.

Its value is appropriately used to setup and enable string modules, but
completely disregarded in the set_brightness paths which only iterate
over the number of strings linearly.
Take an example where only string 2 is enabled with
qcom,enabled_strings=<2>: this string is appropriately enabled but
subsequent brightness changes would have only touched the zero'th
brightness register because num_strings is 1 here.  This is simply
addressed by looking up the string for this index in the enabled_strings
array just like the other codepaths that iterate over num_strings.

Likewise enabled_strings is now also used in the autodetection path for
consistent behaviour: when a list of strings is specified in DT only
those strings will be probed for autodetection, analogous to how the
number of strings that need to be probed is already bound by
qcom,num-strings.  After all autodetection uses the set_brightness
helpers to set an initial value, which could otherwise end up changing
brightness on a different set of strings.

Fixes: 775d2ffb4a ("backlight: qcom-wled: Restructure the driver for WLED3")
Fixes: 03b2b5e869 ("backlight: qcom-wled: Add support for WLED4 peripheral")
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-10-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 10:53:59 +01:00
Marijn Suijten
de79bcbfaf backlight: qcom-wled: Use cpu_to_le16 macro to perform conversion
[ Upstream commit 0a13935854 ]

The kernel already provides appropriate primitives to perform endianness
conversion which should be used in favour of manual bit-wrangling.

Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-4-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 10:53:59 +01:00
Marijn Suijten
c79f9b8d8e backlight: qcom-wled: Override default length with qcom,enabled-strings
[ Upstream commit 2b4b49602f ]

The length of qcom,enabled-strings as property array is enough to
determine the number of strings to be enabled, without needing to set
qcom,num-strings to override the default number of strings when less
than the default (which is also the maximum) is provided in DT.

This also introduces an extra warning when qcom,num-strings is set,
denoting that it is not necessary to set both anymore.  It is usually
more concise to set just qcom,num-length when a zero-based, contiguous
range of strings is needed (the majority of the cases), or to only set
qcom,enabled-strings when a specific set of indices is desired.

Fixes: 775d2ffb4a ("backlight: qcom-wled: Restructure the driver for WLED3")
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-6-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 10:53:59 +01:00
Marijn Suijten
bf4daf6153 backlight: qcom-wled: Fix off-by-one maximum with default num_strings
[ Upstream commit 5ada78b26f ]

When not specifying num-strings in the DT the default is used, but +1 is
added to it which turns WLED3 into 4 and WLED4/5 into 5 strings instead
of 3 and 4 respectively, causing out-of-bounds reads and register
read/writes.  This +1 exists for a deficiency in the DT parsing code,
and is simply omitted entirely - solving this oob issue - by parsing the
property separately much like qcom,enabled-strings.

This also enables more stringent checks on the maximum value when
qcom,enabled-strings is provided in the DT, by parsing num-strings after
enabled-strings to allow it to check against (and in a subsequent patch
override) the length of enabled-strings: it is invalid to set
num-strings higher than that.
The DT currently utilizes it to get around an incorrect fixed read of
four elements from that array (has been addressed in a prior patch) by
setting a lower num-strings where desired.

Fixes: 93c64f1ea1 ("leds: add Qualcomm PM8941 WLED driver")
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-By: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-5-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 10:53:59 +01:00
Marijn Suijten
09aed85e8c backlight: qcom-wled: Pass number of elements to read to read_u32_array
[ Upstream commit e29e24bdab ]

of_property_read_u32_array takes the number of elements to read as last
argument. This does not always need to be 4 (sizeof(u32)) but should
instead be the size of the array in DT as read just above with
of_property_count_elems_of_size.

To not make such an error go unnoticed again the driver now bails
accordingly when of_property_read_u32_array returns an error.
Surprisingly the indentation of newlined arguments is lining up again
after prepending `rc = `.

Fixes: 775d2ffb4a ("backlight: qcom-wled: Restructure the driver for WLED3")
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-3-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 10:53:59 +01:00
Marijn Suijten
f4ed4fc504 backlight: qcom-wled: Validate enabled string indices in DT
[ Upstream commit c05b21ebc5 ]

The strings passed in DT may possibly cause out-of-bounds register
accesses and should be validated before use.

Fixes: 775d2ffb4a ("backlight: qcom-wled: Restructure the driver for WLED3")
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-2-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 10:53:59 +01:00
Marek Vasut
7d0341b37d video: backlight: Drop maximum brightness override for brightness zero
commit 33a5471f8d upstream.

The note in c2adda27d2 ("video: backlight: Add of_find_backlight helper
in backlight.c") says that gpio-backlight uses brightness as power state.
This has been fixed since in ec665b756e ("backlight: gpio-backlight:
Correct initial power state handling") and other backlight drivers do not
require this workaround. Drop the workaround.

This fixes the case where e.g. pwm-backlight can perfectly well be set to
brightness 0 on boot in DT, which without this patch leads to the display
brightness to be max instead of off.

Fixes: c2adda27d2 ("video: backlight: Add of_find_backlight helper in backlight.c")
Cc: <stable@vger.kernel.org> # 5.4+
Cc: <stable@vger.kernel.org> # 4.19.x: ec665b756e: backlight: gpio-backlight: Correct initial power state handling
Signed-off-by: Marek Vasut <marex@denx.de>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-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>
2021-11-18 14:04:30 +01:00
Linus Walleij
063c3d980d backlight: ktd253: Stabilize backlight
[ Upstream commit daa3736151 ]

Remove interrupt disablement during backlight setting. It is
way to dangerous and makes platforms instable by having it
miss vblank IRQs leading to the graphics derailing.

The code is using ndelay() which is not available on
platforms such as ARM and will result in 32 * udelay(1)
which is substantial.

Add some code to detect if an interrupt occurs during the
tight loop and in that case just redo it from the top.

Fixes: 5317f37e48 ("backlight: Add Kinetic KTD253 backlight driver")
Cc: Stephan Gerhold <stephan@gerhold.net>
Reported-by: newbyte@disroot.org
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-22 12:28:02 +02:00
Daniel Thompson
5866b1175d backlight: pwm_bl: Improve bootloader/kernel device handover
commit 79fad92f2e upstream.

Currently there are (at least) two problems in the way pwm_bl starts
managing the enable_gpio pin. Both occur when the backlight is initially
off and the driver finds the pin not already in output mode and, as a
result, unconditionally switches it to output-mode and asserts the signal.

Problem 1: This could cause the backlight to flicker since, at this stage
in driver initialisation, we have no idea what the PWM and regulator are
doing (an unconfigured PWM could easily "rest" at 100% duty cycle).

Problem 2: This will cause us not to correctly honour the
post_pwm_on_delay (which also risks flickers).

Fix this by moving the code to configure the GPIO output mode until after
we have examines the handover state. That allows us to initialize
enable_gpio to off if the backlight is currently off and on if the
backlight is on.

Cc: stable@vger.kernel.org
Reported-by: Marek Vasut <marex@denx.de>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Marek Vasut <marex@denx.de>
Tested-by: Marek Vasut <marex@denx.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-15 09:50:48 +02:00
Uwe Kleine-König
63c49cfa2f 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>
2021-07-20 16:05:45 +02:00
Andy Shevchenko
2e1d76c3b9 backlight: lm3630a_bl: Put fwnode in error case during ->probe()
[ Upstream commit 6d1c32dbed ]

device_for_each_child_node() bumps a reference counting of a returned variable.
We have to balance it whenever we return to the caller.

Cc: Brian Masney <masneyb@onstation.org>
Cc: Dan Murphy <dmurphy@ti.com>
Fixes: 8fbce8efe1 ("backlight: lm3630a: Add firmware node support")
Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Brian Masney <masneyb@onstation.org>
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>
2021-07-14 16:56:38 +02:00
Kiran Gunda
61c1ddd29f backlight: qcom-wled: Fix FSC update issue for WLED5
[ Upstream commit 4d6e9cdff7 ]

Currently, for WLED5, the FSC (Full scale current) setting is not
updated properly due to driver toggling the wrong register after
an FSC update.

On WLED5 we should only toggle the MOD_SYNC bit after a brightness
update. For an FSC update we need to toggle the SYNC bits instead.

Fix it by adopting the common wled3_sync_toggle() for WLED5 and
introducing new code to the brightness update path to compensate.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
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>
2021-05-11 14:47:25 +02:00
Obeida Shamoun
918a45b653 backlight: qcom-wled: Use sink_addr for sync toggle
[ Upstream commit cdfd4c689e ]

WLED3_SINK_REG_SYNC is, as the name implies, a sink register offset.
Therefore, use the sink address as base instead of the ctrl address.

This fixes the sync toggle on wled4, which can be observed by the fact
that adjusting brightness now works.

It has no effect on wled3 because sink and ctrl base addresses are the
same.  This allows adjusting the brightness without having to disable
then reenable the module.

Signed-off-by: Obeida Shamoun <oshmoun100@googlemail.com>
Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Kiran Gunda <kgunda@codeaurora.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-11 14:47:25 +02:00
Linus Torvalds
6448cbf662 Merge tag 'backlight-next-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight
Pull backlight updates from Lee Jones:
 "New Drivers:
   - Add support for KTD253

  Fix-ups:
   - Add Device Tree documentation; common, kinetic,ktd253
   - Use correct header(s); tosa_lcd, tosa_bl

  Bug Fixes:
   - Fix refcount imbalance; sky81452-backlight"

* tag 'backlight-next-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: tosa_bl: Include the right header
  backlight: tosa_lcd: Include the right header
  backlight: Add Kinetic KTD253 backlight driver
  dt-bindings: backlight: Add Kinetic KTD253 bindings
  dt-bindings: backlight: Add some common backlight properties
  backlight: sky81452-backlight: Fix refcount imbalance on error
2020-10-14 15:59:42 -07:00
Linus Walleij
97ecfda1a8 backlight: tosa_bl: Include the right header
The Tosa backlight driver was converted to use GPIO descriptors
in 0b0cb52bd8
("video: backlight: tosa: Use GPIO lookup table") but
still includes <linux/gpio.h> rather than <linux/gpio/consumer.h>.
Fix it.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-09-08 12:31:19 +01:00
Linus Walleij
a47a2b98f3 backlight: tosa_lcd: Include the right header
The Tosa backlight LCDE driver was converted to use GPIO descriptors
in 0b0cb52bd8
("video: backlight: tosa: Use GPIO lookup table") but
still includes <linux/gpio.h> rather than <linux/gpio/consumer.h>.
Fix it.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-09-08 12:30:02 +01:00
Linus Walleij
5317f37e48 backlight: Add Kinetic KTD253 backlight driver
The Kinetic KTD253 backlight driver is controlled with a
single GPIO line, but still supports a range of brightness
settings by sending fast pulses on the line.

This is based off the source code release for the Samsung
GT-S7710 mobile phone.

Cc: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-08-28 11:48:04 +01:00
dinghao.liu@zju.edu.cn
b7a4f80bc3 backlight: sky81452-backlight: Fix refcount imbalance on error
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>
2020-08-28 10:25:54 +01:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Linus Torvalds
fded091988 Merge tag 'pwm/for-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm
Pull pwm updates from Thierry Reding:
 "The majority of this batch is conversion of the PWM period and duty
  cycle to 64-bit unsigned integers, which is required so that some
  types of hardware can generate the full range of signals that they're
  capable of.

  The remainder is mostly minor fixes and cleanups"

* tag 'pwm/for-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
  pwm: bcm-iproc: handle clk_get_rate() return
  pwm: Replace HTTP links with HTTPS ones
  pwm: omap-dmtimer: Repair pwm_omap_dmtimer_chip's broken kerneldoc header
  pwm: mediatek: Provide missing kerneldoc description for 'soc' arg
  pwm: bcm-kona: Remove impossible comparison when validating duty cycle
  pwm: bcm-iproc: Remove impossible comparison when validating duty cycle
  pwm: iqs620a: Use lowercase hexadecimal literals for consistency
  pwm: Convert period and duty cycle to u64
  clk: pwm: Use 64-bit division function
  backlight: pwm_bl: Use 64-bit division function
  pwm: sun4i: Use nsecs_to_jiffies to avoid a division
  pwm: sifive: Use 64-bit division macro
  pwm: iqs620a: Use 64-bit division
  pwm: imx27: Use 64-bit division macro
  pwm: imx-tpm: Use 64-bit division macro
  pwm: clps711x: Use 64-bit division macro
  hwmon: pwm-fan: Use 64-bit division macro
  drm/i915: Use 64-bit division macro
2020-08-14 16:00:09 -07:00
Linus Torvalds
96f970feeb Merge tag 'backlight-next-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight
Pull backlight updates from Lee Jones:
 "Core Framework:
   - Trivial: Code refactoring
   - New API backlight_is_blank()
   - New API backlight_get_brightness()
   - Additional/reworked documentation
   - Remove 'extern' labels from prototypes
   - Drop backlight_put()
   - Staticify of_find_backlight()

  Driver Removal:
   - Removal of unused OT200 driver
   - Removal of unused Generic Backlight driver

  Fix-ups
   - Bunch of W=1 warning fixes
   - Convert to GPIO descriptors; sky81452
   - Move platform data handling into driver; sky81452
   - Remove superfluous code; lms501kf03
   - Many instances of using new APIs"

* tag 'backlight-next-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight: (34 commits)
  video: backlight: cr_bllcd: Remove unused variable 'intensity'
  backlight: backlight: Make of_find_backlight static
  backlight: backlight: Drop backlight_put()
  backlight: Use backlight_get_brightness() throughout
  backlight: jornada720_bl: Introduce backlight_is_blank()
  backlight: gpio_backlight: Simplify update_status()
  backlight: cr_bllcd: Introduce gpio-backlight semantics
  backlight: as3711_bl: Simplify update_status
  backlight: backlight: Introduce backlight_get_brightness()
  doc-rst: Wire-up Backlight kernel-doc documentation
  backlight: backlight: Add overview and update existing doc
  backlight: backlight: Drop extern from prototypes
  backlight: generic_bl: Remove this driver as it is unused
  backlight: backlight: Document enums in backlight.h
  backlight: backlight: Document inline functions in backlight.h
  backlight: backlight: Improve backlight_device documentation
  backlight: backlight: Improve backlight_properties documentation
  backlight: backlight: Improve backlight_ops documentation
  backlight: backlight: Add backlight_is_blank()
  backlight: backlight: Refactor fb_notifier_callback()
  ...
2020-08-11 13:48:02 -07:00
Lee Jones
7eb99a39ef video: backlight: cr_bllcd: Remove unused variable 'intensity'
Fixes the following kernel build warning:

 drivers/video/backlight/cr_bllcd.c: In function ‘cr_backlight_set_intensity’:
 drivers/video/backlight/cr_bllcd.c:62:6: warning: unused variable ‘intensity’ [-Wunused-variable]
 62 | int intensity = bd->props.brightness;
 | ^~~~~~~~~

Cc: Jingoo Han <jingoohan1@gmail.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-fbdev@vger.kernel.org
Fixes: 24d34617c2 ("backlight: cr_bllcd: Introduce gpio-backlight semantics")
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-21 15:45:45 +01:00
Sam Ravnborg
b6539a11e8 backlight: backlight: Make of_find_backlight static
There are no external users of of_find_backlight, as they have all
changed to use the managed version. Make of_find_backlight static to
prevent new external users.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-20 10:27:11 +01:00
Sam Ravnborg
0f6a3256fd backlight: backlight: Drop backlight_put()
There are no external users of backlight_put(). Drop it and open code
the two users in backlight.c.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-20 10:27:09 +01:00
Sam Ravnborg
51d53e5b06 backlight: Use backlight_get_brightness() throughout
Introduce the backlight_get_brightness() helper in all
video/backlight/* drivers. This simplifies the code and align the
implementation of the update_status() operation across the different
backlight drivers.

Some of the drivers gains a little extra functionality by the change
as they now respect the fb_blank() ioctl.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-20 10:27:06 +01:00
Sam Ravnborg
a00a5feb1e backlight: jornada720_bl: Introduce backlight_is_blank()
Use the backlight_is_blank() helper to simplify the code a bit.

The jornada720_bl driver distinguish between backlight off
and brightness set to 0.

Thus this driver turn off backlight only when backlight_is_blank()
returns true.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-20 10:27:05 +01:00
Sam Ravnborg
de7b490cdf backlight: gpio_backlight: Simplify update_status()
Introduce the use of backlight_get_brightness() to simplify the
update_status() operation. With the simpler implementation drop the
gpio_backlight_get_next_brightness() helper as it was now a
one-liner.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-20 10:27:05 +01:00
Sam Ravnborg
24d34617c2 backlight: cr_bllcd: Introduce gpio-backlight semantics
cr_bllcd can turn backlight ON or OFF.

Fix semantitics so they equals what we know from gpio-backlight.

 brightness == 0   => backlight off
 brightness == 1   => backlight on

Use the backlight_get_brightness() helper to simplify the code.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-20 10:27:04 +01:00
Sam Ravnborg
5a09765dde backlight: as3711_bl: Simplify update_status
Replaces the open-coded checks of the state, with the
backlight_get_brightness() helper. This increases readability of the
code and align the functionality across the drivers.

Furthermore drop the debug prints in update_status().
If we need debug printing then we can add it to the backlight core.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-20 10:27:03 +01:00
Sam Ravnborg
a1230eb2e3 backlight: backlight: Add overview and update existing doc
Add overview chapter to backlight.c.

Update existing kernel-doc to follow a more consistent style and drop
kernel-doc for deprecated functions.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-20 10:26:20 +01:00
Sam Ravnborg
7ecdea4a02 backlight: generic_bl: Remove this driver as it is unused
The backlight_bl driver required initialization using
struct generic_bl_info. As there are no more references
to this struct there is no users left.
So it is safe to delete the driver.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-20 10:26:08 +01:00
Sam Ravnborg
4edfe2248d backlight: backlight: Refactor fb_notifier_callback()
Increase readability of fb_notifier_callback() by removing
a few indent levels.

No functional change.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-20 10:17:04 +01:00
Lee Jones
c847e429db video: backlight: sky81452-backlight: Fix some kerneldoc issues
Firstly, all lines must begin with a '*'.  Secondly, arg descriptions
must be spelt correctly, so fix misspelling of 'gpioD_enable' and
'short_detecTion_threshold'

Fixes the following W=1 kernel build warning(s):

 drivers/video/backlight/sky81452-backlight.c:46: warning: bad line:                 If it is not defined, default name is lcd-backlight.
 drivers/video/backlight/sky81452-backlight.c:64: warning: Function parameter or member 'gpiod_enable' not described in 'sky81452_bl_platform_data'
 drivers/video/backlight/sky81452-backlight.c:64: warning: Function parameter or member 'short_detection_threshold' not described in 'sky81452_bl_platform_data'

Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-08 14:08:26 +01:00
Lee Jones
e17c7461a2 backlight: qcom-wled: Remove unused configs for LED3 and LED4
Fixes W=1 warnings:

 drivers/video/backlight/qcom-wled.c:1294:34: warning: ‘wled4_string_cfg’ defined but not used [-Wunused-const-variable=]
 1294 | static const struct wled_var_cfg wled4_string_cfg = {
 | ^~~~~~~~~~~~~~~~
 drivers/video/backlight/qcom-wled.c:1290:34: warning: ‘wled3_string_cfg’ defined but not used [-Wunused-const-variable=]
 1290 | static const struct wled_var_cfg wled3_string_cfg = {
 | ^~~~~~~~~~~~~~~~

Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: linux-arm-msm@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-06 08:11:43 +01:00
Lee Jones
3e799ccda3 backlight: lm3630a_bl: Remove invalid checks for unsigned int < 0
unsigned ints 'sources' and 'bank' cannot be less than LM3630A_SINK_0 (0)
and LM3630A_BANK_0 (0) respecitively, so change the logic to only check
for thier two possible valid values.

Fixes W=1 warnings:

 drivers/video/backlight/lm3630a_bl.c: In function ‘lm3630a_parse_led_sources’:
 drivers/video/backlight/lm3630a_bl.c:394:18: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
 394 | if (sources[i] < LM3630A_SINK_0 || sources[i] > LM3630A_SINK_1)
 | ^
 drivers/video/backlight/lm3630a_bl.c: In function ‘lm3630a_parse_bank’:
 drivers/video/backlight/lm3630a_bl.c:415:11: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
 415 | if (bank < LM3630A_BANK_0 || bank > LM3630A_BANK_1)
 | ^

Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Jeong <gshark.jeong@gmail.com>
Cc: LDD MLP <ldd-mlp@list.ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-06 08:11:43 +01:00
Lee Jones
6c05632d63 backlight: backlight: Supply description for function args in existing Kerneldocs
Kerneldoc syntax is used, but not complete.  Descriptions required.

Prevents warnings like:

 drivers/video/backlight/backlight.c:329: warning: Function parameter or member 'reason' not described in 'backlight_force_update'
 drivers/video/backlight/backlight.c:354: warning: Function parameter or member 'props' not described in 'backlight_device_register'

Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Jamey Hicks <jamey.hicks@hp.com>
Cc: Andrew Zabolotny <zap@homelink.ru>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-06 08:11:42 +01:00
Lee Jones
7099c930fa backlight: ili922x: Add missing kerneldoc description for ili922x_reg_dump()'s arg
Kerneldoc syntax is used, but not complete.  Descriptions required.

Prevents warnings like:

 drivers/video/backlight/ili922x.c:298: warning: Function parameter or member 'spi' not described in 'ili922x_reg_dump'

Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Software Engineering <sbabic@denx.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-06 08:11:42 +01:00
Lee Jones
ee555c1dbe backlight: ili922x: Remove invalid use of kerneldoc syntax
Kerneldoc is for documenting function arguments and return values.

Prevents warnings like:

 drivers/video/backlight/ili922x.c:127: warning: cannot understand function prototype: 'int ili922x_id = 1; '
 drivers/video/backlight/ili922x.c:136: warning: cannot understand function prototype: 'struct ili922x '

Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Software Engineering <sbabic@denx.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-06 08:11:42 +01:00
Lee Jones
0e0428be20 backlight: ili922x: Add missing kerneldoc descriptions for CHECK_FREQ_REG() args
Kerneldoc syntax is used, but not complete.  Descriptions required.

Prevents warnings like:

 drivers/video/backlight/ili922x.c:116: warning: Function parameter or member 's' not described in 'CHECK_FREQ_REG'
 drivers/video/backlight/ili922x.c:116: warning: Function parameter or member 'x' not described in 'CHECK_FREQ_REG'

Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Software Engineering <sbabic@denx.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-06 08:11:41 +01:00
Lee Jones
4160ebacd3 backlight: lcd: Add missing kerneldoc entry for 'struct device parent'
This has been missing since the conversion to 'struct device' in 2007.

Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Jamey Hicks <jamey.hicks@hp.com>
Cc: Andrew Zabolotny <zap@homelink.ru>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-06 08:11:41 +01:00
Lee Jones
81357f818f backlight: lms501kf03: Remove unused const variables
W=1 kernel build reports:

 drivers/video/backlight/lms501kf03.c:96:28: warning: ‘seq_sleep_in’ defined but not used [-Wunused-const-variable=]
 96 | static const unsigned char seq_sleep_in[] = {
 | ^~~~~~~~~~~~
 drivers/video/backlight/lms501kf03.c:92:28: warning: ‘seq_up_dn’ defined but not used [-Wunused-const-variable=]
 92 | static const unsigned char seq_up_dn[] = {
 | ^~~~~~~~~

Either 'seq_sleep_in' nor 'seq_up_dn' have been used since the
driver first landed in 2013.

Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-06 08:11:41 +01:00
Linus Walleij
f3528630e2 backlight: lms501kf03: Drop unused include
This driver includes <linux/gpio.h> but does not use any
symbols from that file, drop the include.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-01 10:56:27 +01:00
Linus Walleij
e994734fdc backlight: Delete the OT200 backlight driver
This driver has no in-kernel users. The device can only be populated
by board files since it does not support device tree nor ACPI,
and nothing in the kernel creates a device named "ot200-backlight".

This driver has been in the kernel since 2012. If it is used by
out-of-tree code that code should have been upstreamed by now,
it's been 8 years.

It uses the idiomatic forked GPIO of the CS5535 which combines
pin control and GPIO into its private custom interface, which
causes me a headache because that is not how we do things these
days: we creates separate pin control and GPIO drivers.

Delete this unused driver.

Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-01 10:55:56 +01:00
Linus Walleij
08bf73a6f0 backlight: sky81452: Privatize platform data
The only way the platform data for the SKY81452 ever gets populated
is through the device tree.

The MFD device is bothered with this for no reason at all. Just
allocate the platform data in the driver and be happy.

Cc: Gyungoh Yoo <jack.yoo@skyworksinc.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-01 10:40:11 +01:00
Linus Walleij
e1915eec54 backlight: sky81452: Convert to GPIO descriptors
The SKY81452 backlight driver just obtains a GPIO (named "gpios"
in the device tree) drives it high and leaves it high until the
driver is removed.

Switch to use GPIO descriptors for this, simple and
straight-forward.

Cc: Gyungoh Yoo <jack.yoo@skyworksinc.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-01 10:39:32 +01:00
Wolfram Sang
9e1b93b9f6 video: backlight: tosa_lcd: convert to use i2c_new_client_device()
Move away from the deprecated API and return the shiny new ERRPTR where
useful.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-06-19 09:20:25 +02:00
Guru Das Srinagesh
134ada17db backlight: pwm_bl: Use 64-bit division function
Since the PWM framework is switching struct pwm_state.period's datatype
to u64, prepare for this transition by using div_u64 to handle a 64-bit
dividend instead of a straight division operation.

Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2020-06-17 20:42:10 +02:00
Wang Qing
a9b9b2af40 backlight: lm3533_bl: Use kobj_to_dev() instead
Use kobj_to_dev() instead of container_of()

Signed-off-by: Wang Qing <wangqing@vivo.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-06-16 09:03:04 +01:00
Noralf Trønnes
479da1f538 backlight: Add backlight_device_get_by_name()
Add a way to lookup a backlight device based on its name.
Will be used by a USB display gadget getting the name from configfs.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-05-11 07:39:16 +01:00
Subbaraman Narayanamurthy
62a1d3f623 backlight: qcom-wled: Add support for WLED5 peripheral that is present on PM8150L PMICs
PM8150L WLED supports the following:
    - Two modulators and each sink can use any of the modulator
    - Multiple CABC selection options from which one can be selected/enabled
    - Multiple brightness width selection (12 bits to 15 bits)

Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>
Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-05-06 11:01:36 +01:00