diff options
| -rw-r--r-- | Documentation/leds-class.txt | 12 | ||||
| -rw-r--r-- | drivers/leds/led-class.c | 3 | ||||
| -rw-r--r-- | drivers/leds/led-triggers.c | 12 | ||||
| -rw-r--r-- | drivers/leds/leds.h | 7 | ||||
| -rw-r--r-- | drivers/leds/ledtrig-timer.c | 23 |
5 files changed, 47 insertions, 10 deletions
diff --git a/Documentation/leds-class.txt b/Documentation/leds-class.txt index 56757c751d6..18860ad9935 100644 --- a/Documentation/leds-class.txt +++ b/Documentation/leds-class.txt @@ -19,6 +19,12 @@ optimises away. Complex triggers whilst available to all LEDs have LED specific parameters and work on a per LED basis. The timer trigger is an example. +The timer trigger will periodically change the LED brightness between +LED_OFF and the current brightness setting. The "on" and "off" time can +be specified via /sys/class/leds/<device>/delay_{on,off} in milliseconds. +You can change the brightness value of a LED independently of the timer +trigger. However, if you set the brightness value to LED_OFF it will +also disable the timer trigger. You can change triggers in a similar manner to the way an IO scheduler is chosen (via /sys/class/leds/<device>/trigger). Trigger specific @@ -63,9 +69,9 @@ value if it is called with *delay_on==0 && *delay_off==0 parameters. In this case the driver should give back the chosen value through delay_on and delay_off parameters to the leds subsystem. -Any call to the brightness_set() callback function should cancel the -previously programmed hardware blinking function so setting the brightness -to 0 can also cancel the blinking of the LED. +Setting the brightness to zero with brightness_set() callback function +should completely turn off the LED and cancel the previously programmed +hardware blinking function, if any. Known Issues diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c index 63aad90247c..a8dd59ebedf 100644 --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c @@ -51,6 +51,9 @@ static ssize_t led_brightness_store(struct device *dev, if (count == size) { ret = count; + + if (state == LED_OFF) + led_trigger_remove(led_cdev); led_set_brightness(led_cdev, state); } diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c index 13c9026d68a..21dd9690944 100644 --- a/drivers/leds/led-triggers.c +++ b/drivers/leds/led-triggers.c @@ -45,9 +45,7 @@ ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr, trigger_name[len - 1] = '\0'; if (!strcmp(trigger_name, "none")) { - down_write(&led_cdev->trigger_lock); - led_trigger_set(led_cdev, NULL); - up_write(&led_cdev->trigger_lock); + led_trigger_remove(led_cdev); return count; } @@ -139,6 +137,13 @@ void led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger) led_cdev->trigger = trigger; } +void led_trigger_remove(struct led_classdev *led_cdev) +{ + down_write(&led_cdev->trigger_lock); + led_trigger_set(led_cdev, NULL); + up_write(&led_cdev->trigger_lock); +} + void led_trigger_set_default(struct led_classdev *led_cdev) { struct led_trigger *trig; @@ -231,6 +236,7 @@ void led_trigger_unregister_simple(struct led_trigger *trigger) /* Used by LED Class */ EXPORT_SYMBOL_GPL(led_trigger_set); +EXPORT_SYMBOL_GPL(led_trigger_remove); EXPORT_SYMBOL_GPL(led_trigger_set_default); EXPORT_SYMBOL_GPL(led_trigger_show); EXPORT_SYMBOL_GPL(led_trigger_store); diff --git a/drivers/leds/leds.h b/drivers/leds/leds.h index 12b6fe93b13..0214799639f 100644 --- a/drivers/leds/leds.h +++ b/drivers/leds/leds.h @@ -27,6 +27,11 @@ static inline void led_set_brightness(struct led_classdev *led_cdev, led_cdev->brightness_set(led_cdev, value); } +static inline int led_get_brightness(struct led_classdev *led_cdev) +{ + return led_cdev->brightness; +} + extern struct rw_semaphore leds_list_lock; extern struct list_head leds_list; @@ -34,9 +39,11 @@ extern struct list_head leds_list; void led_trigger_set_default(struct led_classdev *led_cdev); void led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger); +void led_trigger_remove(struct led_classdev *led_cdev); #else #define led_trigger_set_default(x) do {} while(0) #define led_trigger_set(x, y) do {} while(0) +#define led_trigger_remove(x) do {} while(0) #endif ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr, diff --git a/drivers/leds/ledtrig-timer.c b/drivers/leds/ledtrig-timer.c index 82c55d6e490..706297765d9 100644 --- a/drivers/leds/ledtrig-timer.c +++ b/drivers/leds/ledtrig-timer.c @@ -25,6 +25,9 @@ #include "leds.h" struct timer_trig_data { + int brightness_on; /* LED brightness during "on" period. + * (LED_OFF < brightness_on <= LED_FULL) + */ unsigned long delay_on; /* milliseconds on */ unsigned long delay_off; /* milliseconds off */ struct timer_list timer; @@ -34,17 +37,26 @@ static void led_timer_function(unsigned long data) { struct led_classdev *led_cdev = (struct led_classdev *) data; struct timer_trig_data *timer_data = led_cdev->trigger_data; - unsigned long brightness = LED_OFF; - unsigned long delay = timer_data->delay_off; + unsigned long brightness; + unsigned long delay; if (!timer_data->delay_on || !timer_data->delay_off) { led_set_brightness(led_cdev, LED_OFF); return; } - if (!led_cdev->brightness) { - brightness = LED_FULL; + brightness = led_get_brightness(led_cdev); + if (!brightness) { + /* Time to switch the LED on. */ + brightness = timer_data->brightness_on; delay = timer_data->delay_on; + } else { + /* Store the current brightness value to be able + * to restore it when the delay_off period is over. + */ + timer_data->brightness_on = brightness; + brightness = LED_OFF; + delay = timer_data->delay_off; } led_set_brightness(led_cdev, brightness); @@ -156,6 +168,9 @@ static void timer_trig_activate(struct led_classdev *led_cdev) if (!timer_data) return; + timer_data->brightness_on = led_get_brightness(led_cdev); + if (timer_data->brightness_on == LED_OFF) + timer_data->brightness_on = LED_FULL; led_cdev->trigger_data = timer_data; init_timer(&timer_data->timer); |