From 28ee086d5b36aab2931f6740e409bb0fb6c65e5f Mon Sep 17 00:00:00 2001 From: Richard Purdie Date: Thu, 8 Feb 2007 22:25:09 +0000 Subject: 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 --- drivers/video/backlight/lcd.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/video/backlight/lcd.c') 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; -- cgit v1.2.3