From e6c6fea5c314d90dbfca4983f2ea46388aab3bb0 Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann Date: Tue, 5 Mar 2024 17:22:34 +0100 Subject: backlight: Match backlight device against struct fb_info.bl_dev 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 Reviewed-by: Daniel Thompson Reviewed-by: Javier Martinez Canillas Link: https://lore.kernel.org/r/20240305162425.23845-2-tzimmermann@suse.de Signed-off-by: Lee Jones --- drivers/video/backlight/backlight.c | 8 ++++++-- drivers/video/fbdev/core/fb_backlight.c | 6 ++++++ include/linux/fb.h | 9 +++++++++ 3 files changed, 21 insertions(+), 2 deletions(-) diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c index 86e1cdc8e369..4f7973c6fcc7 100644 --- a/drivers/video/backlight/backlight.c +++ b/drivers/video/backlight/backlight.c @@ -98,7 +98,9 @@ static int fb_notifier_callback(struct notifier_block *self, { struct backlight_device *bd; struct fb_event *evdata = data; - int node = evdata->info->node; + struct fb_info *info = evdata->info; + struct backlight_device *fb_bd = fb_bl_device(info); + int node = info->node; int fb_blank = 0; /* If we aren't interested in this event, skip it immediately ... */ @@ -110,7 +112,9 @@ static int fb_notifier_callback(struct notifier_block *self, if (!bd->ops) goto out; - if (bd->ops->check_fb && !bd->ops->check_fb(bd, evdata->info)) + if (bd->ops->check_fb && !bd->ops->check_fb(bd, info)) + goto out; + if (fb_bd && fb_bd != bd) goto out; fb_blank = *(int *)evdata->data; diff --git a/drivers/video/fbdev/core/fb_backlight.c b/drivers/video/fbdev/core/fb_backlight.c index e2d3b3adc870..6fdaa9f81be9 100644 --- a/drivers/video/fbdev/core/fb_backlight.c +++ b/drivers/video/fbdev/core/fb_backlight.c @@ -30,4 +30,10 @@ void fb_bl_default_curve(struct fb_info *fb_info, u8 off, u8 min, u8 max) mutex_unlock(&fb_info->bl_curve_mutex); } EXPORT_SYMBOL_GPL(fb_bl_default_curve); + +struct backlight_device *fb_bl_device(struct fb_info *info) +{ + return info->bl_dev; +} +EXPORT_SYMBOL(fb_bl_device); #endif diff --git a/include/linux/fb.h b/include/linux/fb.h index 0dd27364d56f..75c5f800467c 100644 --- a/include/linux/fb.h +++ b/include/linux/fb.h @@ -738,6 +738,15 @@ extern struct fb_info *framebuffer_alloc(size_t size, struct device *dev); extern void framebuffer_release(struct fb_info *info); extern void fb_bl_default_curve(struct fb_info *fb_info, u8 off, u8 min, u8 max); +#if IS_ENABLED(CONFIG_FB_BACKLIGHT) +struct backlight_device *fb_bl_device(struct fb_info *info); +#else +static inline struct backlight_device *fb_bl_device(struct fb_info *info) +{ + return NULL; +} +#endif + /* fbmon.c */ #define FB_MAXTIMINGS 0 #define FB_VSYNCTIMINGS 1 -- cgit v1.2.3