kernel/linux.git/drivers/video/backlight/backlight.c, branch v6.6.133

fbdev: Split frame buffer support in FB and FB_CORE symbols

2023-07-22T10:25:04+00:00

Currently the CONFIG_FB option has to be enabled even if no legacy fbdev drivers are needed (e.g: only to have support for framebuffer consoles). The DRM subsystem has a fbdev emulation layer, but depends on CONFIG_FB and so it can only be enabled if that dependency is enabled as well. That means fbdev drivers have to be explicitly disabled if users want to enable CONFIG_FB, only to use fbcon and/or the DRM fbdev emulation layer. This patch introduces a non-visible CONFIG_FB_CORE symbol that could be enabled just to have core support needed for CONFIG_DRM_FBDEV_EMULATION, allowing CONFIG_FB to be disabled (and automatically disabling all the fbdev drivers). Nothing from fb_backlight.o and fbmon.o is used by the DRM fbdev emulation layer so these two objects can be compiled out when CONFIG_FB is disabled. Signed-off-by: Javier Martinez Canillas Reviewed-by: Arnd Bergmann Tested-by: Arnd Bergmann Acked-by: Helge Deller Link: https://patchwork.freedesktop.org/patch/msgid/20230719081544.741051-4-javierm@redhat.com

driver core: class: remove module * from class_create()

2023-03-17T14:16:33+00:00

The module pointer in class_create() never actually did anything, and it shouldn't have been requred to be set as a parameter even if it did something. So just remove it and fix up all callers of the function in the kernel tree at the same time. Cc: "Rafael J. Wysocki" Acked-by: Benjamin Tissoires Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

backlight: backlight: Fix doc for backlight_device_get_by_name

2023-02-22T10:53:26+00:00

backlight_put() has been dropped, we should call put_device() to drop the reference taken by backlight_device_get_by_name(). Fixes: 0f6a3256fd81 ("backlight: backlight: Drop backlight_put()") Signed-off-by: Miaoqian Lin Reviewed-by: Daniel Thompson Signed-off-by: Lee Jones Link: https://lore.kernel.org/r/20221215071902.424005-1-linmq006@gmail.com

backlight: backlight: Slighly simplify devm_of_find_backlight()

2022-03-08T10:47:28+00:00

Use devm_add_action_or_reset() instead of devm_add_action()+hand writing what is done in the release function, should an error occur. This is more straightforward and saves a few lines of code. While at it, remove a useless test in devm_backlight_release(). 'data' is known to be not NULL when this function is called. Signed-off-by: Christophe JAILLET Reviewed-by: Daniel Thompson Signed-off-by: Lee Jones Link: https://lore.kernel.org/r/f998a4291d865273afa0d1f85764a9ac7fbc1b64.1644738084.git.christophe.jaillet@wanadoo.fr

backlight: Propagate errors from get_brightness()

2021-09-23T09:48:00+00:00

backlight.h documents "struct backlight_ops->get_brightness()" to return a negative errno on failure. So far these errors have not been handled in the backlight core. This leads to negative values being exposed through sysfs although only positive values are documented to be reported. Signed-off-by: Thomas Weißschuh Reviewed-by: Daniel Thompson Signed-off-by: Lee Jones

video: backlight: Drop maximum brightness override for brightness zero

2021-09-22T07:32:48+00:00

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

backlight: backlight: Make of_find_backlight static

2020-07-20T09:27:11+00:00

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 Reviewed-by: Daniel Thompson Signed-off-by: Lee Jones

backlight: backlight: Drop backlight_put()

2020-07-20T09:27:09+00:00

There are no external users of backlight_put(). Drop it and open code the two users in backlight.c. Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Signed-off-by: Lee Jones

backlight: backlight: Add overview and update existing doc

2020-07-20T09:26:20+00:00

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 Reviewed-by: Daniel Thompson Reviewed-by: Emil Velikov Signed-off-by: Lee Jones

backlight: backlight: Refactor fb_notifier_callback()

2020-07-20T09:17:04+00:00

Increase readability of fb_notifier_callback() by removing a few indent levels. No functional change. Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Reviewed-by: Emil Velikov Signed-off-by: Lee Jones