#define _LINUX_BACKLIGHT_H
#include <linux/device.h>
+#include <linux/mutex.h>
#include <linux/notifier.h>
+/* Notes on locking:
+ *
+ * backlight_device->ops_lock is an internal backlight lock protecting the
+ * ops pointer 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.
+ *
+ * Most drivers don't need locking on their get_brightness() method.
+ * If yours does, you need to implement it in the driver. You can use the
+ * update_lock mutex if appropriate.
+ *
+ * Any other use of the locks below is probably wrong.
+ */
+
struct backlight_device;
struct fb_info;
-/* This structure defines all the properties of a backlight
- (usually attached to a LCD). */
-struct backlight_properties {
- /* Owner module */
- struct module *owner;
-
+struct backlight_ops {
/* Notify the backlight driver some property has changed */
int (*update_status)(struct backlight_device *);
/* Return the current backlight brightness (accounting for power,
/* Check if given framebuffer device is the one bound to this backlight;
return 0 if not, !=0 if it is. If NULL, backlight always matches the fb. */
int (*check_fb)(struct fb_info *);
+};
+/* This structure defines all the properties of a backlight */
+struct backlight_properties {
/* Current User requested brightness (0 - max_brightness) */
int brightness;
/* Maximal value for brightness (read-only) */
};
struct backlight_device {
- /* This protects the 'props' field. If 'props' is NULL, the driver that
+ /* Backlight properties */
+ struct backlight_properties props;
+
+ /* Serialise access to update_status method */
+ struct mutex update_lock;
+
+ /* This protects the 'ops' field. If 'ops' 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;
- /* If this is NULL, the backing module is unloaded */
- struct backlight_properties *props;
+ struct mutex ops_lock;
+ struct backlight_ops *ops;
+
/* The framebuffer notifier block */
struct notifier_block fb_notif;
- /* The class device structure */
- struct class_device class_dev;
+
+ struct device dev;
};
+static inline void backlight_update_status(struct backlight_device *bd)
+{
+ mutex_lock(&bd->update_lock);
+ if (bd->ops && bd->ops->update_status)
+ bd->ops->update_status(bd);
+ mutex_unlock(&bd->update_lock);
+}
+
extern struct backlight_device *backlight_device_register(const char *name,
- struct device *dev,void *devdata,struct backlight_properties *bp);
+ struct device *dev, void *devdata, struct backlight_ops *ops);
extern void backlight_device_unregister(struct backlight_device *bd);
-#define to_backlight_device(obj) container_of(obj, struct backlight_device, class_dev)
+#define to_backlight_device(obj) container_of(obj, struct backlight_device, dev)
+
+static inline void * bl_get_data(struct backlight_device *bl_dev)
+{
+ return dev_get_drvdata(&bl_dev->dev);
+}
+
+struct generic_bl_info {
+ const char *name;
+ int max_intensity;
+ int default_intensity;
+ int limit_mask;
+ void (*set_bl_intensity)(int intensity);
+ void (*kick_battery)(void);
+};
#endif