Remove support for fb events from backlight subsystem. Provide the
helper backlight_notify_blank_all() instead. Also export the existing
helper backlight_notify_blank() to update a single backlight device.
In fbdev, call either helper to inform the backlight subsystem of
changes to a display's blank state. If the framebuffer device has a
specific backlight, only update this one; otherwise update all.
v4:
- protect blacklight declarations with IS_REACHABLE() (kernel test robot)
v3:
- declare empty fb_bl_notify_blank() as static inline (kernel test robot)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Simona Vetter <simona.vetter@ffwll.ch>
Reviewed-by: "Daniel Thompson (RISCstar)" <danielt@kernel.org>
Link: https://lore.kernel.org/r/20250321095517.313713-7-tzimmermann@suse.de
Signed-off-by: Lee Jones <lee@kernel.org>
Framebuffer drivers for devices with dedicated backlight are supposed
to set struct fb_info.bl_dev to the backlight's respective device. Use
the value to match backlight and framebuffer in the backlight core code.
The code first tests against struct backlight_ops.check_ops. If this
test succeeds, it performs the test against fbdev. So backlight drivers
can override the later test as before.
Fbdev's backlight support depends on CONFIG_FB_BACKLIGHT. To avoid
ifdef in the code, the new helper fb_bl_device() returns the backlight
device, or NULL if the config option has been disabled. The test in
the backlight code will then do nothing.
v4:
* declare empty fb_bl_device() as static inline
* export fb_bl_device()
v3:
* hide ifdef in fb_bl_device() (Lee)
* no if-else blocks (Andy)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20240305162425.23845-2-tzimmermann@suse.de
Signed-off-by: Lee Jones <lee@kernel.org>
Move framebuffer and backlight helpers into separate files. Leave
fbsysfs.c to sysfs-related code. No functional changes.
The framebuffer helpers are not in fbmem.c because they are under
GPL-2.0-or-later copyright, while fbmem.c is GPL-2.0.
v2:
* include <linux/mutex.h> (Sam)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230613110953.24176-34-tzimmermann@suse.de
Thomas Zimmermann