diff options
| author | Richard Purdie <rpurdie@rpsys.net> | 2007-02-08 22:25:09 +0000 |
|---|---|---|
| committer | Richard Purdie <rpurdie@rpsys.net> | 2007-02-20 08:38:45 +0000 |
| commit | 28ee086d5b36aab2931f6740e409bb0fb6c65e5f (patch) | |
| tree | 0a308c80affcc39c2c869f29f1109e5ee9d6140f /drivers/video/backlight/lcd.c | |
| parent | a8db3c1948eb30cd6988b5b96b654f591e6280b1 (diff) | |
| download | linux-next-28ee086d5b36aab2931f6740e409bb0fb6c65e5f.tar.gz | |
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/lcd.c')
| -rw-r--r-- | drivers/video/backlight/lcd.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c index 959024812abc..1e1e61a4b5da 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; |