backlight: Rework backlight/fb interaction simplifying, lots
fb_info->bl_mutex is badly thought out and the backlight class doesn't
need it if the framebuffer/backlight register/unregister order is
consistent, particularly after the backlight locking fixes.
Fix the drivers to use the order:
backlight_device_register()
register_framebuffer()
unregister_framebuffer()
backlight_device_unregister()
and turn bl_mutex into a lock for the bl_curve data only.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
diff --git a/drivers/video/aty/radeon_backlight.c b/drivers/video/aty/radeon_backlight.c
index 9cfceca..f94e461 100644
--- a/drivers/video/aty/radeon_backlight.c
+++ b/drivers/video/aty/radeon_backlight.c
@@ -29,17 +29,13 @@
static int radeon_bl_get_level_brightness(struct radeon_bl_privdata *pdata,
int level)
{
- struct fb_info *info = pdata->rinfo->info;
int rlevel;
- mutex_lock(&info->bl_mutex);
-
/* Get and convert the value */
+ /* No locking of bl_curve since we read a single value */
rlevel = pdata->rinfo->info->bl_curve[level] *
FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL;
- mutex_unlock(&info->bl_mutex);
-
if (rlevel < 0)
rlevel = 0;
else if (rlevel > MAX_RADEON_LEVEL)
@@ -187,12 +183,10 @@
machine_is_compatible("PowerBook6,5");
#endif
- mutex_lock(&rinfo->info->bl_mutex);
rinfo->info->bl_dev = bd;
fb_bl_default_curve(rinfo->info, 0,
63 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL,
217 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL);
- mutex_unlock(&rinfo->info->bl_mutex);
bd->props->brightness = radeon_bl_data.max_brightness;
bd->props->power = FB_BLANK_UNBLANK;
@@ -216,29 +210,22 @@
void radeonfb_bl_exit(struct radeonfb_info *rinfo)
{
-#ifdef CONFIG_PMAC_BACKLIGHT
- mutex_lock(&pmac_backlight_mutex);
-#endif
+ struct backlight_device *bd = rinfo->info->bl_dev;
- mutex_lock(&rinfo->info->bl_mutex);
- if (rinfo->info->bl_dev) {
+ if (bd) {
struct radeon_bl_privdata *pdata;
#ifdef CONFIG_PMAC_BACKLIGHT
- if (pmac_backlight == rinfo->info->bl_dev)
+ mutex_lock(&pmac_backlight_mutex);
+ if (pmac_backlight == bd)
pmac_backlight = NULL;
+ mutex_unlock(&pmac_backlight_mutex);
#endif
-
- pdata = class_get_devdata(&rinfo->info->bl_dev->class_dev);
- backlight_device_unregister(rinfo->info->bl_dev);
+ pdata = class_get_devdata(&bd->class_dev);
+ backlight_device_unregister(bd);
kfree(pdata);
rinfo->info->bl_dev = NULL;
printk("radeonfb: Backlight unloaded\n");
}
- mutex_unlock(&rinfo->info->bl_mutex);
-
-#ifdef CONFIG_PMAC_BACKLIGHT
- mutex_unlock(&pmac_backlight_mutex);
-#endif
}