Remove support for fb events from the led backlight trigger. Provide
the helper ledtrig_backlight_blank() instead. Call it from fbdev to
inform the trigger of changes to a display's blank state.
Fbdev maintains a list of all installed notifiers. Instead of the fbdev
notifiers, maintain an internal list of led backlight triggers.
v2:
- maintain global list of led backlight triggers (Lee)
- avoid IS_REACHABLE() in source file (Lee)
- notify on changes to blank state instead of display state
- use lock guards
- initialize led list and list mutex
Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
---
drivers/leds/trigger/ledtrig-backlight.c | 41 +++++++++---------------
drivers/video/fbdev/core/fbmem.c | 19 +++++------
include/linux/leds.h | 6 ++++
3 files changed, 32 insertions(+), 34 deletions(-)
diff --git a/drivers/leds/trigger/ledtrig-backlight.c b/drivers/leds/trigger/ledtrig-backlight.c
index 8e66d55a6c82..2d351de81927 100644
--- a/drivers/leds/trigger/ledtrig-backlight.c
+++ b/drivers/leds/trigger/ledtrig-backlight.c
@@ -10,7 +10,6 @@
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/init.h>
-#include <linux/fb.h>
#include <linux/leds.h>
#include "../leds.h"
@@ -21,10 +20,14 @@ struct bl_trig_notifier {
struct led_classdev *led;
int brightness;
int old_status;
- struct notifier_block notifier;
unsigned invert;
+
+ struct list_head entry;
};
+static DEFINE_MUTEX(ledtrig_backlight_list_mutex);
+static LIST_HEAD(ledtrig_backlight_list);
+
static void ledtrig_backlight_notify_blank(struct bl_trig_notifier *n, int new_status)
{
struct led_classdev *led = n->led;
@@ -42,25 +45,15 @@ static void ledtrig_backlight_notify_blank(struct bl_trig_notifier *n, int new_s
n->old_status = new_status;
}
-static int fb_notifier_callback(struct notifier_block *p,
- unsigned long event, void *data)
+void ledtrig_backlight_blank(bool blank)
{
- struct bl_trig_notifier *n = container_of(p,
- struct bl_trig_notifier, notifier);
- struct fb_event *fb_event = data;
- int *blank;
- int new_status;
-
- /* If we aren't interested in this event, skip it immediately ... */
- if (event != FB_EVENT_BLANK)
- return 0;
-
- blank = fb_event->data;
- new_status = *blank ? BLANK : UNBLANK;
+ struct bl_trig_notifier *n;
+ int new_status = blank ? BLANK : UNBLANK;
- ledtrig_backlight_notify_blank(n, new_status);
+ guard(mutex)(&ledtrig_backlight_list_mutex);
- return 0;
+ list_for_each_entry(n, &ledtrig_backlight_list, entry)
+ ledtrig_backlight_notify_blank(n, new_status);
}
static ssize_t bl_trig_invert_show(struct device *dev,
@@ -106,8 +99,6 @@ ATTRIBUTE_GROUPS(bl_trig);
static int bl_trig_activate(struct led_classdev *led)
{
- int ret;
-
struct bl_trig_notifier *n;
n = kzalloc(sizeof(struct bl_trig_notifier), GFP_KERNEL);
@@ -118,11 +109,9 @@ static int bl_trig_activate(struct led_classdev *led)
n->led = led;
n->brightness = led->brightness;
n->old_status = UNBLANK;
- n->notifier.notifier_call = fb_notifier_callback;
- ret = fb_register_client(&n->notifier);
- if (ret)
- dev_err(led->dev, "unable to register backlight trigger\n");
+ guard(mutex)(&ledtrig_backlight_list_mutex);
+ list_add(&n->entry, &ledtrig_backlight_list);
return 0;
}
@@ -131,7 +120,9 @@ static void bl_trig_deactivate(struct led_classdev *led)
{
struct bl_trig_notifier *n = led_get_trigger_data(led);
- fb_unregister_client(&n->notifier);
+ guard(mutex)(&ledtrig_backlight_list_mutex);
+ list_del(&n->entry);
+
kfree(n);
}
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index 001662c606d7..f089f72ec75a 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -16,6 +16,7 @@
#include <linux/fb.h>
#include <linux/fbcon.h>
#include <linux/lcd.h>
+#include <linux/leds.h>
#include <video/nomodeset.h>
@@ -369,11 +370,17 @@ static void fb_lcd_notify_blank(struct fb_info *info)
lcd_notify_blank_all(info->device, power);
}
+static void fb_ledtrig_backlight_notify_blank(struct fb_info *info)
+{
+ if (info->blank == FB_BLANK_UNBLANK)
+ ledtrig_backlight_blank(false);
+ else
+ ledtrig_backlight_blank(true);
+}
+
int fb_blank(struct fb_info *info, int blank)
{
int old_blank = info->blank;
- struct fb_event event;
- int data[2];
int ret;
if (!info->fbops->fb_blank)
@@ -382,11 +389,6 @@ int fb_blank(struct fb_info *info, int blank)
if (blank > FB_BLANK_POWERDOWN)
blank = FB_BLANK_POWERDOWN;
- data[0] = blank;
- data[1] = old_blank;
- event.info = info;
- event.data = data;
-
info->blank = blank;
ret = info->fbops->fb_blank(blank, info);
@@ -395,8 +397,7 @@ int fb_blank(struct fb_info *info, int blank)
fb_bl_notify_blank(info, old_blank);
fb_lcd_notify_blank(info);
-
- fb_notifier_call_chain(FB_EVENT_BLANK, &event);
+ fb_ledtrig_backlight_notify_blank(info);
return 0;
diff --git a/include/linux/leds.h b/include/linux/leds.h
index 98f9719c924c..b3f0aa081064 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -640,6 +640,12 @@ static inline void ledtrig_flash_ctrl(bool on) {}
static inline void ledtrig_torch_ctrl(bool on) {}
#endif
+#if IS_REACHABLE(CONFIG_LEDS_TRIGGER_BACKLIGHT)
+void ledtrig_backlight_blank(bool blank);
+#else
+static inline void ledtrig_backlight_blank(bool blank) {}
+#endif
+
/*
* Generic LED platform data for describing LED names and default triggers.
*/
--
2.48.1
