Improve the documentation for backlight_properties 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 | 101 +++++++++++++++++++++++++++++++++----- 1 file changed, 90 insertions(+), 11 deletions(-)
diff --git a/include/linux/backlight.h b/include/linux/backlight.h index 51f0d0abea25..c81b77af44d4 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -118,28 +118,107 @@ struct backlight_ops { int (*check_fb)(struct backlight_device *bd, struct fb_info *info); };
-/* This structure defines all the properties of a backlight */ +/** + * struct backlight_properties - backlight properties + * + * This structure defines all the properties of a backlight. + */ struct backlight_properties { - /* Current User requested brightness (0 - max_brightness) */ + /** + * @brightness: + * + * The current requested brightness by the user. + * The backlight core makes sure the range is (0 - max_brightness) + * when the brightness is set via the sysfs attribute: + * /sys/class/backlight/<backlight>/brightness. + * + * This value can be set in the backlight_properties passed + * to devm_backlight_device_register() to set a default brightness + * value. + */ int brightness; - /* Maximal value for brightness (read-only) */ + + /** + * @max_brightness: + * + * The maximum brightness value. + * + * This value must be set in the backlight_properties passed + * to devm_backlight_device_register(). + * + * This property must not be modified by a driver except + * before registering the backlight device as explained above. + */ int max_brightness; - /* Current FB Power mode (0: full on, 1..3: power saving - modes; 4: full off), see FB_BLANK_XXX */ + + /** + * @power: + * + * The current power mode. User space configure the power mode using + * the sysfs attribute: /sys/class/backlight/<backlight>/bl_power + * When the power property is updated update_status() is called. + * + * The possible values are: (0: full on, 1..3: power saving + * modes; 4: full off), see FB_BLANK_XXX. + * + * When the backlight device is enabled @power is set + * to FB_BLANK_UNBLANK. When the backlight device is disabled + * @power is set to FB_BLANK_POWERDOWN. + */ int power; - /* FB Blanking active? (values as for power) */ - /* Due to be removed, please use (state & BL_CORE_FBBLANK) */ + + /** + * @fb_blank: + * + * When the FBIOBLANK ioctl is called fb_blank is set to the + * blank parameter and the update_status() operation is called. + * + * When the backlight device is enabled @fb_blank is set + * to FB_BLANK_UNBLANK. When the backlight device is disabled + * @fb_blank is set to FB_BLANK_POWERDOWN. + * + * This property must not be modified by a driver. + * The backlight driver shall never read this variable, + * as the necessary info is avaialble via the state. + * + * fb_blank is deprecated and will be removed. + */ int fb_blank; - /* Backlight type */ + + /** + * @type: + * + * The type of backlight supported. + * The backlight type allows userspace to make appropriate + * policy desicions based on the backlight type. + * + * This value must be set in the backlight_properties + * passed to devm_backlight_device_register(). + */ enum backlight_type type; - /* Flags used to signal drivers of state changes */ + + /** + * @state: + * + * The state property is used to inform drivers of state changes + * when the update_status() operation is called. + * The state is a bitmask. BL_CORE_FBBLANK is set when the display + * is expected to be blank. BL_CORE_SUSPENDED is set when the + * driver is suspended. + * + * This property must not be modified by a driver. + */ unsigned int state; - /* Type of the brightness scale (linear, non-linear, ...) */ - enum backlight_scale scale;
#define BL_CORE_SUSPENDED (1 << 0) /* backlight is suspended */ #define BL_CORE_FBBLANK (1 << 1) /* backlight is under an fb blank event */
+ /** + * @scale: + * + * The type of the brightness scale (linear, non-linear, ...) + */ + enum backlight_scale scale; };
struct backlight_device {