Remove support for fb events from the lcd subsystem. Provide the
helper lcd_notify_blank_all() instead. In fbdev, call
lcd_notify_blank_all() to inform the lcd subsystem of changes
to a display's blank state.
Fbdev maintains a list of all installed notifiers. Instead of fbdev
notifiers, maintain an internal list of lcd devices.
v2:
- maintain global list of lcd devices
- avoid IS_REACHABLE() in source file
- use lock guards
- initialize lcd list and list mutex
Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
---
drivers/video/backlight/lcd.c | 97 ++++++++------------------------
drivers/video/fbdev/core/fbmem.c | 39 +++++++++++--
include/linux/lcd.h | 21 ++++++-
3 files changed, 78 insertions(+), 79 deletions(-)
diff --git a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c
index f57ff8bcc2fa..b59531d7f4d6 100644
--- a/drivers/video/backlight/lcd.c
+++ b/drivers/video/backlight/lcd.c
@@ -15,9 +15,11 @@
#include <linux/notifier.h>
#include <linux/ctype.h>
#include <linux/err.h>
-#include <linux/fb.h>
#include <linux/slab.h>
+static DEFINE_MUTEX(lcd_dev_list_mutex);
+static LIST_HEAD(lcd_dev_list);
+
static void lcd_notify_blank(struct lcd_device *ld, struct device *display_dev,
int power)
{
@@ -31,6 +33,17 @@ static void lcd_notify_blank(struct lcd_device *ld, struct device *display_dev,
ld->ops->set_power(ld, power);
}
+void lcd_notify_blank_all(struct device *display_dev, int power)
+{
+ struct lcd_device *ld;
+
+ guard(mutex)(&lcd_dev_list_mutex);
+
+ list_for_each_entry(ld, &lcd_dev_list, entry)
+ lcd_notify_blank(ld, display_dev, power);
+}
+EXPORT_SYMBOL(lcd_notify_blank_all);
+
static void lcd_notify_mode_change(struct lcd_device *ld, struct device *display_dev,
unsigned int width, unsigned int height)
{
@@ -44,76 +57,17 @@ static void lcd_notify_mode_change(struct lcd_device *ld, struct device *display
ld->ops->set_mode(ld, width, height);
}
-#if defined(CONFIG_FB) || (defined(CONFIG_FB_MODULE) && \
- defined(CONFIG_LCD_CLASS_DEVICE_MODULE))
-static int to_lcd_power(int fb_blank)
+void lcd_notify_mode_change_all(struct device *display_dev,
+ unsigned int width, unsigned int height)
{
- switch (fb_blank) {
- case FB_BLANK_UNBLANK:
- return LCD_POWER_ON;
- /* deprecated; TODO: should become 'off' */
- case FB_BLANK_NORMAL:
- return LCD_POWER_REDUCED;
- case FB_BLANK_VSYNC_SUSPEND:
- return LCD_POWER_REDUCED_VSYNC_SUSPEND;
- /* 'off' */
- case FB_BLANK_HSYNC_SUSPEND:
- case FB_BLANK_POWERDOWN:
- default:
- return LCD_POWER_OFF;
- }
-}
+ struct lcd_device *ld;
-/* This callback gets called when something important happens inside a
- * framebuffer driver. We're looking if that important event is blanking,
- * and if it is, we're switching lcd power as well ...
- */
-static int fb_notifier_callback(struct notifier_block *self,
- unsigned long event, void *data)
-{
- struct lcd_device *ld = container_of(self, struct lcd_device, fb_notif);
- struct fb_event *evdata = data;
- struct fb_info *info = evdata->info;
- struct lcd_device *fb_lcd = fb_lcd_device(info);
-
- if (fb_lcd && fb_lcd != ld)
- return 0;
-
- if (event == FB_EVENT_BLANK) {
- int power = to_lcd_power(*(int *)evdata->data);
-
- lcd_notify_blank(ld, info->device, power);
- } else {
- const struct fb_videomode *videomode = evdata->data;
-
- lcd_notify_mode_change(ld, info->device, videomode->xres, videomode->yres);
- }
+ guard(mutex)(&lcd_dev_list_mutex);
- return 0;
+ list_for_each_entry(ld, &lcd_dev_list, entry)
+ lcd_notify_mode_change(ld, display_dev, width, height);
}
-static int lcd_register_fb(struct lcd_device *ld)
-{
- memset(&ld->fb_notif, 0, sizeof(ld->fb_notif));
- ld->fb_notif.notifier_call = fb_notifier_callback;
- return fb_register_client(&ld->fb_notif);
-}
-
-static void lcd_unregister_fb(struct lcd_device *ld)
-{
- fb_unregister_client(&ld->fb_notif);
-}
-#else
-static int lcd_register_fb(struct lcd_device *ld)
-{
- return 0;
-}
-
-static inline void lcd_unregister_fb(struct lcd_device *ld)
-{
-}
-#endif /* CONFIG_FB */
-
static ssize_t lcd_power_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
@@ -263,11 +217,8 @@ struct lcd_device *lcd_device_register(const char *name, struct device *parent,
return ERR_PTR(rc);
}
- rc = lcd_register_fb(new_ld);
- if (rc) {
- device_unregister(&new_ld->dev);
- return ERR_PTR(rc);
- }
+ guard(mutex)(&lcd_dev_list_mutex);
+ list_add(&new_ld->entry, &lcd_dev_list);
return new_ld;
}
@@ -284,10 +235,12 @@ void lcd_device_unregister(struct lcd_device *ld)
if (!ld)
return;
+ guard(mutex)(&lcd_dev_list_mutex);
+ list_del(&ld->entry);
+
mutex_lock(&ld->ops_lock);
ld->ops = NULL;
mutex_unlock(&ld->ops_lock);
- lcd_unregister_fb(ld);
device_unregister(&ld->dev);
}
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index c931f270ac34..001662c606d7 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -15,6 +15,7 @@
#include <linux/export.h>
#include <linux/fb.h>
#include <linux/fbcon.h>
+#include <linux/lcd.h>
#include <video/nomodeset.h>
@@ -220,6 +221,12 @@ static int fb_check_caps(struct fb_info *info, struct fb_var_screeninfo *var,
return err;
}
+static void fb_lcd_notify_mode_change(struct fb_info *info,
+ struct fb_videomode *mode)
+{
+ lcd_notify_mode_change_all(info->device, mode->xres, mode->yres);
+}
+
int
fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
{
@@ -227,7 +234,6 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
u32 activate;
struct fb_var_screeninfo old_var;
struct fb_videomode mode;
- struct fb_event event;
u32 unused;
if (var->activate & FB_ACTIVATE_INV_MODE) {
@@ -331,14 +337,38 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
if (ret)
return ret;
- event.info = info;
- event.data = &mode;
- fb_notifier_call_chain(FB_EVENT_MODE_CHANGE, &event);
+ fb_lcd_notify_mode_change(info, &mode);
return 0;
}
EXPORT_SYMBOL(fb_set_var);
+static void fb_lcd_notify_blank(struct fb_info *info)
+{
+ int power;
+
+ switch (info->blank) {
+ case FB_BLANK_UNBLANK:
+ power = LCD_POWER_ON;
+ break;
+ /* deprecated; TODO: should become 'off' */
+ case FB_BLANK_NORMAL:
+ power = LCD_POWER_REDUCED;
+ break;
+ case FB_BLANK_VSYNC_SUSPEND:
+ power = LCD_POWER_REDUCED_VSYNC_SUSPEND;
+ break;
+ /* 'off' */
+ case FB_BLANK_HSYNC_SUSPEND:
+ case FB_BLANK_POWERDOWN:
+ default:
+ power = LCD_POWER_OFF;
+ break;
+ }
+
+ lcd_notify_blank_all(info->device, power);
+}
+
int fb_blank(struct fb_info *info, int blank)
{
int old_blank = info->blank;
@@ -364,6 +394,7 @@ int fb_blank(struct fb_info *info, int blank)
goto err;
fb_bl_notify_blank(info, old_blank);
+ fb_lcd_notify_blank(info);
fb_notifier_call_chain(FB_EVENT_BLANK, &event);
diff --git a/include/linux/lcd.h b/include/linux/lcd.h
index c3ccdff4519a..d4fa03722b72 100644
--- a/include/linux/lcd.h
+++ b/include/linux/lcd.h
@@ -11,7 +11,6 @@
#include <linux/device.h>
#include <linux/mutex.h>
-#include <linux/notifier.h>
#define LCD_POWER_ON (0)
#define LCD_POWER_REDUCED (1) // deprecated; don't use in new code
@@ -79,8 +78,11 @@ struct lcd_device {
const struct lcd_ops *ops;
/* Serialise access to set_power method */
struct mutex update_lock;
- /* The framebuffer notifier block */
- struct notifier_block fb_notif;
+
+ /**
+ * @entry: List entry of all registered lcd devices
+ */
+ struct list_head entry;
struct device dev;
};
@@ -125,6 +127,19 @@ extern void lcd_device_unregister(struct lcd_device *ld);
extern void devm_lcd_device_unregister(struct device *dev,
struct lcd_device *ld);
+#if IS_REACHABLE(CONFIG_LCD_CLASS_DEVICE)
+void lcd_notify_blank_all(struct device *display_dev, int power);
+void lcd_notify_mode_change_all(struct device *display_dev,
+ unsigned int width, unsigned int height);
+#else
+static inline void lcd_notify_blank_all(struct device *display_dev, int power)
+{}
+
+static inline void lcd_notify_mode_change_all(struct device *display_dev,
+ unsigned int width, unsigned int height)
+{}
+#endif
+
#define to_lcd_device(obj) container_of(obj, struct lcd_device, dev)
static inline void * lcd_get_data(struct lcd_device *ld_dev)
--
2.48.1
