linux-stable.git/drivers/video/backlight, branch v5.4.285

backlight: lp8788: Fully initialize backlight_properties during probe

2024-03-26T22:22:23+00:00

[ Upstream commit 392346827fbe8a7fd573dfb145170d7949f639a6 ]

props is stack allocated and the fields that are not explcitly set
by the probe function need to be zeroed or we'll get undefined behaviour
(especially so power/blank states)!

Fixes: c5a51053cf3b ("backlight: add new lp8788 backlight driver")
Signed-off-by: Daniel Thompson 
Link: https://lore.kernel.org/r/20240220153532.76613-4-daniel.thompson@linaro.org
Signed-off-by: Lee Jones 
Signed-off-by: Sasha Levin

backlight: lm3639: Fully initialize backlight_properties during probe

2024-03-26T22:22:23+00:00

[ Upstream commit abb5a5d951fbea3feb5c4ba179b89bb96a1d3462 ]

props is stack allocated and the fields that are not explcitly set
by the probe function need to be zeroed or we'll get undefined behaviour
(especially so power/blank states)!

Fixes: 0f59858d5119 ("backlight: add new lm3639 backlight driver")
Signed-off-by: Daniel Thompson 
Link: https://lore.kernel.org/r/20240220153532.76613-3-daniel.thompson@linaro.org
Signed-off-by: Lee Jones 
Signed-off-by: Sasha Levin

backlight: da9052: Fully initialize backlight_properties during probe

2024-03-26T22:22:23+00:00

[ Upstream commit 0285e9efaee8276305db5c52a59baf84e9731556 ]

props is stack allocated and the fields that are not explcitly set
by the probe function need to be zeroed or we'll get undefined behaviour
(especially so power/blank states)!

Fixes: 6ede3d832aaa ("backlight: add driver for DA9052/53 PMIC v1")
Signed-off-by: Daniel Thompson 
Link: https://lore.kernel.org/r/20240220153532.76613-2-daniel.thompson@linaro.org
Signed-off-by: Lee Jones 
Signed-off-by: Sasha Levin

backlight: lm3630a: Don't set bl->props.brightness in get_brightness

2024-03-26T22:22:23+00:00

[ Upstream commit 4bf7ddd2d2f0f8826f25f74c7eba4e2c323a1446 ]

There's no need to set bl->props.brightness, the get_brightness function
is just supposed to return the current brightness and not touch the
struct.

With that done we can also remove the 'goto out' and just return the
value.

Fixes: 0c2a665a648e ("backlight: add Backlight driver for lm3630 chip")
Signed-off-by: Luca Weiss 
Reviewed-by: Daniel Thompson 
Link: https://lore.kernel.org/r/20240220-lm3630a-fixups-v1-2-9ca62f7e4a33@z3ntu.xyz
Signed-off-by: Lee Jones 
Signed-off-by: Sasha Levin

backlight: lm3630a: Initialize backlight_properties on init

2024-03-26T22:22:23+00:00

[ Upstream commit ad9aeb0e3aa90ebdad5fabf9c21783740eb95907 ]

The backlight_properties struct should be initialized to zero before
using, otherwise there will be some random values in the struct.

Fixes: 0c2a665a648e ("backlight: add Backlight driver for lm3630 chip")
Signed-off-by: Luca Weiss 
Reviewed-by: Daniel Thompson 
Link: https://lore.kernel.org/r/20240220-lm3630a-fixups-v1-1-9ca62f7e4a33@z3ntu.xyz
Signed-off-by: Lee Jones 
Signed-off-by: Sasha Levin

backlight/lv5207lp: Compare against struct fb_info.device

2023-09-23T08:59:54+00:00

commit 1ca8819320fd84e7d95b04e7668efc5f9fe9fa5c upstream.

Struct lv5207lp_platform_data refers to a platform device within
the Linux device hierarchy. The test in lv5207lp_backlight_check_fb()
compares it against the fbdev device in struct fb_info.dev, which
is different. Fix the test by comparing to struct fb_info.device.

Fixes a bug in the backlight driver and prepares fbdev for making
struct fb_info.dev optional.

v2:
	* move renames into separate patch (Javier, Sam, Michael)

Fixes: 82e5c40d88f9 ("backlight: Add Sanyo LV5207LP backlight driver")
Signed-off-by: Thomas Zimmermann 
Cc: Laurent Pinchart 
Cc: Yoshinori Sato 
Cc: Rich Felker 
Cc: John Paul Adrian Glaubitz 
Cc: Lee Jones 
Cc: Daniel Thompson 
Cc: Jingoo Han 
Cc: linux-sh@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc:  # v3.12+
Reviewed-by: Javier Martinez Canillas 
Reviewed-by: Sam Ravnborg 
Reviewed-by: Daniel Thompson 
Link: https://patchwork.freedesktop.org/patch/msgid/20230613110953.24176-6-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman

backlight/bd6107: Compare against struct fb_info.device

2023-09-23T08:59:54+00:00

commit 992bdddaabfba19bdc77c1c7a4977b2aa41ec891 upstream.

Struct bd6107_platform_data refers to a platform device within
the Linux device hierarchy. The test in bd6107_backlight_check_fb()
compares it against the fbdev device in struct fb_info.dev, which
is different. Fix the test by comparing to struct fb_info.device.

Fixes a bug in the backlight driver and prepares fbdev for making
struct fb_info.dev optional.

v2:
	* move renames into separate patch (Javier, Sam, Michael)

Fixes: 67b43e590415 ("backlight: Add ROHM BD6107 backlight driver")
Signed-off-by: Thomas Zimmermann 
Cc: Laurent Pinchart 
Cc: Lee Jones 
Cc: Daniel Thompson 
Cc: Jingoo Han 
Cc: dri-devel@lists.freedesktop.org
Cc:  # v3.12+
Reviewed-by: Javier Martinez Canillas 
Reviewed-by: Sam Ravnborg 
Reviewed-by: Daniel Thompson 
Link: https://patchwork.freedesktop.org/patch/msgid/20230613110953.24176-2-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman

backlight/gpio_backlight: Compare against struct fb_info.device

2023-09-23T08:59:54+00:00

commit 7b91d017f77c1bda56f27c2f4bbb70de7c6eca08 upstream.

Struct gpio_backlight_platform_data refers to a platform device within
the Linux device hierarchy. The test in gpio_backlight_check_fb()
compares it against the fbdev device in struct fb_info.dev, which
is different. Fix the test by comparing to struct fb_info.device.

Fixes a bug in the backlight driver and prepares fbdev for making
struct fb_info.dev optional.

v2:
	* move renames into separate patch (Javier, Sam, Michael)

Signed-off-by: Thomas Zimmermann 
Fixes: 8b770e3c9824 ("backlight: Add GPIO-based backlight driver")
Cc: Laurent Pinchart 
Cc: Rich Felker 
Cc: John Paul Adrian Glaubitz 
Cc: Lee Jones 
Cc: Daniel Thompson 
Cc: Jingoo Han 
Cc: linux-sh@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc:  # v3.12+
Reviewed-by: Sam Ravnborg 
Reviewed-by: Daniel Thompson 
Link: https://patchwork.freedesktop.org/patch/msgid/20230613110953.24176-4-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman

video: backlight: Drop maximum brightness override for brightness zero

2021-11-17T08:48:50+00:00

commit 33a5471f8da976bf271a1ebbd6b9d163cb0cb6aa upstream.

The note in c2adda27d202f ("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 ec665b756e6f7 ("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: c2adda27d202f ("video: backlight: Add of_find_backlight helper in backlight.c")
Cc:  # 5.4+
Cc:  # 4.19.x: ec665b756e6f7: backlight: gpio-backlight: Correct initial power state handling
Signed-off-by: Marek Vasut 
Acked-by: Noralf Trønnes 
Reviewed-by: Daniel Thompson 
Signed-off-by: Lee Jones 
Signed-off-by: Greg Kroah-Hartman

backlight: pwm_bl: Improve bootloader/kernel device handover

2021-09-15T07:47:41+00:00

commit 79fad92f2e596f5a8dd085788a24f540263ef887 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 
Signed-off-by: Daniel Thompson 
Acked-by: Marek Vasut 
Tested-by: Marek Vasut 
Signed-off-by: Lee Jones 
Signed-off-by: Greg Kroah-Hartman