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.
Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
---
drivers/video/backlight/backlight.c | 85 ++++---------------------
drivers/video/fbdev/core/fb_backlight.c | 12 ++++
drivers/video/fbdev/core/fbmem.c | 2 +
include/linux/backlight.h | 12 ++--
include/linux/fb.h | 4 ++
5 files changed, 36 insertions(+), 79 deletions(-)
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index 1c43f579396f..9dc93c5e480b 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -15,7 +15,6 @@
#include <linux/notifier.h>
#include <linux/ctype.h>
#include <linux/err.h>
-#include <linux/fb.h>
#include <linux/slab.h>
#ifdef CONFIG_PMAC_BACKLIGHT
@@ -57,10 +56,10 @@
* a hot-key to adjust backlight, the driver must notify the backlight
* core that brightness has changed using backlight_force_update().
*
- * The backlight driver core receives notifications from fbdev and
- * if the event is FB_EVENT_BLANK and if the value of blank, from the
- * FBIOBLANK ioctrl, results in a change in the backlight state the
- * update_status() operation is called.
+ * Display drives can control the backlight device's status using
+ * backlight_notify_blank() and backlight_notify_blank_all(). If this
+ * results in a change in the backlight state the functions call the
+ * update_status() operation.
*/
static struct list_head backlight_dev_list;
@@ -78,11 +77,8 @@ static const char *const backlight_scale_types[] = {
[BACKLIGHT_SCALE_NON_LINEAR] = "non-linear",
};
-#if defined(CONFIG_FB_CORE) || (defined(CONFIG_FB_CORE_MODULE) && \
- defined(CONFIG_BACKLIGHT_CLASS_DEVICE_MODULE))
-static void backlight_notify_blank(struct backlight_device *bd,
- struct device *display_dev,
- bool fb_on, bool prev_fb_on)
+void backlight_notify_blank(struct backlight_device *bd, struct device *display_dev,
+ bool fb_on, bool prev_fb_on)
{
guard(mutex)(&bd->ops_lock);
@@ -103,68 +99,18 @@ static void backlight_notify_blank(struct backlight_device *bd,
}
}
}
+EXPORT_SYMBOL(backlight_notify_blank);
-/*
- * fb_notifier_callback
- *
- * This callback gets called when something important happens inside a
- * framebuffer driver. The backlight core only cares about FB_BLANK_UNBLANK
- * which is reported to the driver using backlight_update_status()
- * as a state change.
- *
- * There may be several fbdev's connected to the backlight device,
- * in which case they are kept track of. A state change is only reported
- * if there is a change in backlight for the specified fbdev.
- */
-static int fb_notifier_callback(struct notifier_block *self,
- unsigned long event, void *data)
+void backlight_notify_blank_all(struct device *display_dev, bool fb_on, bool prev_fb_on)
{
struct backlight_device *bd;
- struct fb_event *evdata = data;
- struct fb_info *info = evdata->info;
- const int *fb_blank = evdata->data;
- struct backlight_device *fb_bd = fb_bl_device(info);
- bool fb_on, prev_fb_on;
-
- /* If we aren't interested in this event, skip it immediately ... */
- if (event != FB_EVENT_BLANK)
- return 0;
-
- bd = container_of(self, struct backlight_device, fb_notif);
-
- if (fb_bd && fb_bd != bd)
- return 0;
-
- fb_on = fb_blank[0] == FB_BLANK_UNBLANK;
- prev_fb_on = fb_blank[1] == FB_BLANK_UNBLANK;
-
- backlight_notify_blank(bd, info->device, fb_on, prev_fb_on);
-
- return 0;
-}
-
-static int backlight_register_fb(struct backlight_device *bd)
-{
- memset(&bd->fb_notif, 0, sizeof(bd->fb_notif));
- bd->fb_notif.notifier_call = fb_notifier_callback;
- return fb_register_client(&bd->fb_notif);
-}
+ guard(mutex)(&backlight_dev_list_mutex);
-static void backlight_unregister_fb(struct backlight_device *bd)
-{
- fb_unregister_client(&bd->fb_notif);
-}
-#else
-static inline int backlight_register_fb(struct backlight_device *bd)
-{
- return 0;
+ list_for_each_entry(bd, &backlight_dev_list, entry)
+ backlight_notify_blank(bd, display_dev, fb_on, prev_fb_on);
}
-
-static inline void backlight_unregister_fb(struct backlight_device *bd)
-{
-}
-#endif /* CONFIG_FB_CORE */
+EXPORT_SYMBOL(backlight_notify_blank_all);
static void backlight_generate_event(struct backlight_device *bd,
enum backlight_update_reason reason)
@@ -455,12 +401,6 @@ struct backlight_device *backlight_device_register(const char *name,
return ERR_PTR(rc);
}
- rc = backlight_register_fb(new_bd);
- if (rc) {
- device_unregister(&new_bd->dev);
- return ERR_PTR(rc);
- }
-
new_bd->ops = ops;
#ifdef CONFIG_PMAC_BACKLIGHT
@@ -547,7 +487,6 @@ void backlight_device_unregister(struct backlight_device *bd)
bd->ops = NULL;
mutex_unlock(&bd->ops_lock);
- backlight_unregister_fb(bd);
device_unregister(&bd->dev);
}
EXPORT_SYMBOL(backlight_device_unregister);
diff --git a/drivers/video/fbdev/core/fb_backlight.c b/drivers/video/fbdev/core/fb_backlight.c
index 6fdaa9f81be9..dbed9696f4c5 100644
--- a/drivers/video/fbdev/core/fb_backlight.c
+++ b/drivers/video/fbdev/core/fb_backlight.c
@@ -1,5 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/backlight.h>
#include <linux/export.h>
#include <linux/fb.h>
#include <linux/mutex.h>
@@ -36,4 +37,15 @@ struct backlight_device *fb_bl_device(struct fb_info *info)
return info->bl_dev;
}
EXPORT_SYMBOL(fb_bl_device);
+
+void fb_bl_notify_blank(struct fb_info *info, int old_blank)
+{
+ bool on = info->blank == FB_BLANK_UNBLANK;
+ bool prev_on = old_blank == FB_BLANK_UNBLANK;
+
+ if (info->bl_dev)
+ backlight_notify_blank(info->bl_dev, info->device, on, prev_on);
+ else
+ backlight_notify_blank_all(info->device, on, prev_on);
+}
#endif
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index 997f0bfcdbb6..993fbee602e0 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -363,6 +363,8 @@ int fb_blank(struct fb_info *info, int blank)
if (ret)
goto err;
+ fb_bl_notify_blank(info, old_blank);
+
fb_notifier_call_chain(FB_EVENT_BLANK, &event);
return 0;
diff --git a/include/linux/backlight.h b/include/linux/backlight.h
index 03723a5478f8..7ed99cfd030f 100644
--- a/include/linux/backlight.h
+++ b/include/linux/backlight.h
@@ -12,7 +12,6 @@
#include <linux/device.h>
#include <linux/fb.h>
#include <linux/mutex.h>
-#include <linux/notifier.h>
#include <linux/types.h>
/**
@@ -278,11 +277,6 @@ struct backlight_device {
*/
const struct backlight_ops *ops;
- /**
- * @fb_notif: The framebuffer notifier block
- */
- struct notifier_block fb_notif;
-
/**
* @entry: List entry of all registered backlight devices
*/
@@ -400,6 +394,12 @@ struct backlight_device *backlight_device_get_by_type(enum backlight_type type);
int backlight_device_set_brightness(struct backlight_device *bd,
unsigned long brightness);
+void backlight_notify_blank(struct backlight_device *bd,
+ struct device *display_dev,
+ bool fb_on, bool prev_fb_on);
+void backlight_notify_blank_all(struct device *display_dev,
+ bool fb_on, bool prev_fb_on);
+
#define to_backlight_device(obj) container_of(obj, struct backlight_device, dev)
/**
diff --git a/include/linux/fb.h b/include/linux/fb.h
index f41d3334ac23..bebf279c8bc6 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -757,11 +757,15 @@ 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);
+void fb_bl_notify_blank(struct fb_info *info, int old_blank);
#else
static inline struct backlight_device *fb_bl_device(struct fb_info *info)
{
return NULL;
}
+
+void fb_bl_notify_blank(struct fb_info *info, int old_blank)
+{ }
#endif
static inline struct lcd_device *fb_lcd_device(struct fb_info *info)
--
2.48.1
