Improve the documentation for backlight_device and adapt it to kernel-doc style.
Signed-off-by: Sam Ravnborg sam@ravnborg.org Cc: Lee Jones lee.jones@linaro.org Cc: Daniel Thompson daniel.thompson@linaro.org Cc: Jingoo Han jingoohan1@gmail.com --- include/linux/backlight.h | 81 ++++++++++++++++++++++++++++----------- 1 file changed, 58 insertions(+), 23 deletions(-)
diff --git a/include/linux/backlight.h b/include/linux/backlight.h index c81b77af44d4..34ba1e444334 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -14,21 +14,6 @@ #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. - */ - enum backlight_update_reason { BACKLIGHT_UPDATE_HOTKEY, BACKLIGHT_UPDATE_SYSFS, @@ -221,30 +206,80 @@ struct backlight_properties { enum backlight_scale scale; };
+/** + * struct backlight_device - backlight device data + * + * This structure holds all data required by a backlight device. + */ struct backlight_device { - /* Backlight properties */ + /** + * @props: + * + * Backlight properties + */ struct backlight_properties props;
- /* Serialise access to update_status method */ + /** + * @update_lock: + * + * update_lock is an internal backlight lock that serialise access + * to the update_status() method. The iupdate_lock mutex shall not be used + * by backlight drivers. + */ 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. */ + /** + * @ops_lock: + * + * ops_lock is an internal backlight lock that protects the ops pointer + * and is used around all accesses to ops and when the operations are + * invoked. The mutex shall not be used by backlight drivers. + */ struct mutex ops_lock; + + /** + * @ops: + * + * Pointer to the backlight operations. 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. + */ const struct backlight_ops *ops;
- /* The framebuffer notifier block */ + /** + * @fb_notif: + * + * The framebuffer notifier block + */ struct notifier_block fb_notif;
- /* list entry of all registered backlight devices */ + /** + * @entry: + * + * List entry of all registered backlight devices + */ struct list_head entry;
+ /** + * @dev: + * + * Parent device. + */ struct device dev;
- /* Multiple framebuffers may share one backlight device */ + /** + * @fb_bl_on: + * + * Multiple fbdev's may share one backlight device. The fb_bl_on + * records the state of the individual fbdev. + */ bool fb_bl_on[FB_MAX];
+ /** + * @use_count: + * + * The number of uses of fb_bl_on. + */ int use_count; };