diff options
| author | Richard Purdie <rpurdie@rpsys.net> | 2007-02-08 22:25:09 (GMT) |
|---|---|---|
| committer | Richard Purdie <rpurdie@rpsys.net> | 2007-02-20 08:38:45 (GMT) |
| commit | 28ee086d5b36aab2931f6740e409bb0fb6c65e5f (patch) | |
| tree | 0a308c80affcc39c2c869f29f1109e5ee9d6140f /drivers/video/backlight | |
| parent | a8db3c1948eb30cd6988b5b96b654f591e6280b1 (diff) | |
| download | linux-28ee086d5b36aab2931f6740e409bb0fb6c65e5f.tar.xz | |
backlight: Fix external uses of backlight internal semaphore
backlight_device->sem has a very specific use as documented in the
header file. The external users of this are using it for a different
reason, to serialise access to the update_status() method.
backlight users were supposed to implement their own internal
serialisation of update_status() if needed but everyone is doing
things differently and incorrectly. Therefore add a global mutex to
take care of serialisation for everyone, once and for all.
Locking for get_brightness remains optional since most users don't
need it.
Also update the lcd class in a similar way.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Diffstat (limited to 'drivers/video/backlight')
| -rw-r--r-- | drivers/video/backlight/backlight.c | 10 | ||||
| -rw-r--r-- | drivers/video/backlight/lcd.c | 1 |
2 files changed, 5 insertions, 6 deletions
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c index 7a85be4..347081d 100644 --- a/drivers/video/backlight/backlight.c +++ b/drivers/video/backlight/backlight.c @@ -37,8 +37,7 @@ static int fb_notifier_callback(struct notifier_block *self, if (!bd->props->check_fb || bd->props->check_fb(evdata->info)) { bd->props->fb_blank = *(int *)evdata->data; - if (bd->props && bd->props->update_status) - bd->props->update_status(bd); + backlight_update_status(bd); } up(&bd->sem); return 0; @@ -97,8 +96,7 @@ static ssize_t backlight_store_power(struct class_device *cdev, const char *buf, if (bd->props) { pr_debug("backlight: set power to %d\n", power); bd->props->power = power; - if (bd->props->update_status) - bd->props->update_status(bd); + backlight_update_status(bd); rc = count; } up(&bd->sem); @@ -140,8 +138,7 @@ static ssize_t backlight_store_brightness(struct class_device *cdev, const char pr_debug("backlight: set brightness to %d\n", brightness); bd->props->brightness = brightness; - if (bd->props->update_status) - bd->props->update_status(bd); + backlight_update_status(bd); rc = count; } } @@ -230,6 +227,7 @@ struct backlight_device *backlight_device_register(const char *name, if (!new_bd) return ERR_PTR(-ENOMEM); + mutex_init(&new_bd->update_lock); init_MUTEX(&new_bd->sem); new_bd->props = bp; memset(&new_bd->class_dev, 0, sizeof(new_bd->class_dev)); diff --git a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c index 9590248..1e1e61a 100644 --- a/drivers/video/backlight/lcd.c +++ b/drivers/video/backlight/lcd.c @@ -198,6 +198,7 @@ struct lcd_device *lcd_device_register(const char *name, void *devdata, return ERR_PTR(-ENOMEM); init_MUTEX(&new_ld->sem); + mutex_init(&new_ld->update_lock); new_ld->props = lp; memset(&new_ld->class_dev, 0, sizeof(new_ld->class_dev)); new_ld->class_dev.class = &lcd_class; |