dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

backlight: Convert semaphore -> mutex 

Convert internal semaphore to a mutex

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
This commit is contained in:
Richard Purdie 2007-02-08 22:53:55 +00:00
parent 28ee086d5b
commit 249040dc7f
4 changed files with 37 additions and 37 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
drivers/video/backlight/backlight.c
View File

@ -32,14 +32,14 @@ static int fb_notifier_callback(struct notifier_block *self,
return 0;
bd = container_of(self, struct backlight_device, fb_notif);
down(&bd->sem);
mutex_lock(&bd->props_lock);
if (bd->props)
if (!bd->props->check_fb ||
bd->props->check_fb(evdata->info)) {
bd->props->fb_blank = *(int *)evdata->data;
backlight_update_status(bd);
}
up(&bd->sem);
mutex_unlock(&bd->props_lock);
return 0;
}
@ -71,10 +71,10 @@ static ssize_t backlight_show_power(struct class_device *cdev, char *buf)
int rc = -ENXIO;
struct backlight_device *bd = to_backlight_device(cdev);
down(&bd->sem);
mutex_lock(&bd->props_lock);
if (bd->props)
rc = sprintf(buf, "%d\n", bd->props->power);
up(&bd->sem);
mutex_unlock(&bd->props_lock);
return rc;
}
@ -92,14 +92,14 @@ static ssize_t backlight_store_power(struct class_device *cdev, const char *buf,
if (size != count)
return -EINVAL;
down(&bd->sem);
mutex_lock(&bd->props_lock);
if (bd->props) {
pr_debug("backlight: set power to %d\n", power);
bd->props->power = power;
backlight_update_status(bd);
rc = count;
}
up(&bd->sem);
mutex_unlock(&bd->props_lock);
return rc;
}
@ -109,10 +109,10 @@ static ssize_t backlight_show_brightness(struct class_device *cdev, char *buf)
int rc = -ENXIO;
struct backlight_device *bd = to_backlight_device(cdev);
down(&bd->sem);
mutex_lock(&bd->props_lock);
if (bd->props)
rc = sprintf(buf, "%d\n", bd->props->brightness);
up(&bd->sem);
mutex_unlock(&bd->props_lock);
return rc;
}
@ -130,7 +130,7 @@ static ssize_t backlight_store_brightness(struct class_device *cdev, const char
if (size != count)
return -EINVAL;
down(&bd->sem);
mutex_lock(&bd->props_lock);
if (bd->props) {
if (brightness > bd->props->max_brightness)
rc = -EINVAL;
@ -142,7 +142,7 @@ static ssize_t backlight_store_brightness(struct class_device *cdev, const char
rc = count;
}
}
up(&bd->sem);
mutex_unlock(&bd->props_lock);
return rc;
}
@ -152,10 +152,10 @@ static ssize_t backlight_show_max_brightness(struct class_device *cdev, char *bu
int rc = -ENXIO;
struct backlight_device *bd = to_backlight_device(cdev);
down(&bd->sem);
mutex_lock(&bd->props_lock);
if (bd->props)
rc = sprintf(buf, "%d\n", bd->props->max_brightness);
up(&bd->sem);
mutex_unlock(&bd->props_lock);
return rc;
}
@ -166,10 +166,10 @@ static ssize_t backlight_show_actual_brightness(struct class_device *cdev,
int rc = -ENXIO;
struct backlight_device *bd = to_backlight_device(cdev);
down(&bd->sem);
mutex_lock(&bd->props_lock);
if (bd->props && bd->props->get_brightness)
rc = sprintf(buf, "%d\n", bd->props->get_brightness(bd));
up(&bd->sem);
mutex_unlock(&bd->props_lock);
return rc;
}
@ -228,7 +228,7 @@ struct backlight_device *backlight_device_register(const char *name,
return ERR_PTR(-ENOMEM);
mutex_init(&new_bd->update_lock);
init_MUTEX(&new_bd->sem);
mutex_init(&new_bd->props_lock);
new_bd->props = bp;
memset(&new_bd->class_dev, 0, sizeof(new_bd->class_dev));
new_bd->class_dev.class = &backlight_class;
@ -285,9 +285,9 @@ void backlight_device_unregister(struct backlight_device *bd)
class_device_remove_file(&bd->class_dev,
&bl_class_device_attributes[i]);
down(&bd->sem);
mutex_lock(&bd->props_lock);
bd->props = NULL;
up(&bd->sem);
mutex_unlock(&bd->props_lock);
backlight_unregister_fb(bd);

30
drivers/video/backlight/lcd.c
View File

@ -31,11 +31,11 @@ static int fb_notifier_callback(struct notifier_block *self,
return 0;
ld = container_of(self, struct lcd_device, fb_notif);
down(&ld->sem);
mutex_lock(&ld->props_lock);
if (ld->props)
if (!ld->props->check_fb || ld->props->check_fb(evdata->info))
ld->props->set_power(ld, *(int *)evdata->data);
up(&ld->sem);
mutex_unlock(&ld->props_lock);
return 0;
}
@ -66,12 +66,12 @@ static ssize_t lcd_show_power(struct class_device *cdev, char *buf)
int rc;
struct lcd_device *ld = to_lcd_device(cdev);
down(&ld->sem);
mutex_lock(&ld->props_lock);
if (ld->props && ld->props->get_power)
rc = sprintf(buf, "%d\n", ld->props->get_power(ld));
else
rc = -ENXIO;
up(&ld->sem);
mutex_unlock(&ld->props_lock);
return rc;
}
@ -89,13 +89,13 @@ static ssize_t lcd_store_power(struct class_device *cdev, const char *buf, size_
if (size != count)
return -EINVAL;
down(&ld->sem);
mutex_lock(&ld->props_lock);
if (ld->props && ld->props->set_power) {
pr_debug("lcd: set power to %d\n", power);
ld->props->set_power(ld, power);
rc = count;
}
up(&ld->sem);
mutex_unlock(&ld->props_lock);
return rc;
}
@ -105,10 +105,10 @@ static ssize_t lcd_show_contrast(struct class_device *cdev, char *buf)
int rc = -ENXIO;
struct lcd_device *ld = to_lcd_device(cdev);
down(&ld->sem);
mutex_lock(&ld->props_lock);
if (ld->props && ld->props->get_contrast)
rc = sprintf(buf, "%d\n", ld->props->get_contrast(ld));
up(&ld->sem);
mutex_unlock(&ld->props_lock);
return rc;
}
@ -126,13 +126,13 @@ static ssize_t lcd_store_contrast(struct class_device *cdev, const char *buf, si
if (size != count)
return -EINVAL;
down(&ld->sem);
mutex_lock(&ld->props_lock);
if (ld->props && ld->props->set_contrast) {
pr_debug("lcd: set contrast to %d\n", contrast);
ld->props->set_contrast(ld, contrast);
rc = count;
}
up(&ld->sem);
mutex_unlock(&ld->props_lock);
return rc;
}
@ -142,10 +142,10 @@ static ssize_t lcd_show_max_contrast(struct class_device *cdev, char *buf)
int rc = -ENXIO;
struct lcd_device *ld = to_lcd_device(cdev);
down(&ld->sem);
mutex_lock(&ld->props_lock);
if (ld->props)
rc = sprintf(buf, "%d\n", ld->props->max_contrast);
up(&ld->sem);
mutex_unlock(&ld->props_lock);
return rc;
}
@ -197,7 +197,7 @@ struct lcd_device *lcd_device_register(const char *name, void *devdata,
if (!new_ld)
return ERR_PTR(-ENOMEM);
init_MUTEX(&new_ld->sem);
mutex_init(&new_ld->props_lock);
mutex_init(&new_ld->update_lock);
new_ld->props = lp;
memset(&new_ld->class_dev, 0, sizeof(new_ld->class_dev));
@ -253,9 +253,9 @@ void lcd_device_unregister(struct lcd_device *ld)
class_device_remove_file(&ld->class_dev,
&lcd_class_device_attributes[i]);
down(&ld->sem);
mutex_lock(&ld->props_lock);
ld->props = NULL;
up(&ld->sem);
mutex_unlock(&ld->props_lock);
lcd_unregister_fb(ld);
class_device_unregister(&ld->class_dev);
}

6
include/linux/backlight.h
View File

@ -14,8 +14,8 @@
/* Notes on locking:
*
* backlight_device->sem is an internal backlight lock protecting the props
* field and no code outside the core should need to touch it.
* backlight_device->props_lock is an internal backlight lock protecting the
* props field and no code outside the core should need to touch it.
*
* Access to update_status() is serialised by the update_lock mutex since
* most drivers seem to need this and historically get it wrong.
@ -57,7 +57,7 @@ struct backlight_device {
/* This protects the 'props' field. If 'props' is NULL, the driver that
registered this device has been unloaded, and if class_get_devdata()
points to something in the body of that driver, it is also invalid. */
struct semaphore sem;
struct mutex props_lock;
/* If this is NULL, the backing module is unloaded */
struct backlight_properties *props;
/* Serialise access to update_status method */

4
include/linux/lcd.h
View File

@ -14,7 +14,7 @@
/* Notes on locking:
*
* lcd_device->sem is an internal backlight lock protecting the props
* lcd_device->props_lock is an internal backlight lock protecting the props
* field and no code outside the core should need to touch it.
*
* Access to set_power() is serialised by the update_lock mutex since
@ -52,7 +52,7 @@ struct lcd_device {
/* This protects the 'props' field. If 'props' is NULL, the driver that
registered this device has been unloaded, and if class_get_devdata()
points to something in the body of that driver, it is also invalid. */
struct semaphore sem;
struct mutex props_lock;
/* If this is NULL, the backing module is unloaded */
struct lcd_properties *props;
/* Serialise access to set_power method */