#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;
{
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);
mod_timer(&timer_data->timer, jiffies + msecs_to_jiffies(delay));
}
-static ssize_t led_delay_on_show(struct device *dev,
+static ssize_t led_delay_on_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct timer_trig_data *timer_data = led_cdev->trigger_data;
- sprintf(buf, "%lu\n", timer_data->delay_on);
-
- return strlen(buf) + 1;
+ return sprintf(buf, "%lu\n", timer_data->delay_on);
}
-static ssize_t led_delay_on_store(struct device *dev,
+static ssize_t led_delay_on_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
count++;
if (count == size) {
- timer_data->delay_on = state;
- mod_timer(&timer_data->timer, jiffies + 1);
+ if (timer_data->delay_on != state) {
+ /* the new value differs from the previous */
+ timer_data->delay_on = state;
+
+ /* deactivate previous settings */
+ del_timer_sync(&timer_data->timer);
+
+ /* try to activate hardware acceleration, if any */
+ if (!led_cdev->blink_set ||
+ led_cdev->blink_set(led_cdev,
+ &timer_data->delay_on, &timer_data->delay_off)) {
+ /* no hardware acceleration, blink via timer */
+ mod_timer(&timer_data->timer, jiffies + 1);
+ }
+ }
ret = count;
}
return ret;
}
-static ssize_t led_delay_off_show(struct device *dev,
+static ssize_t led_delay_off_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct timer_trig_data *timer_data = led_cdev->trigger_data;
- sprintf(buf, "%lu\n", timer_data->delay_off);
-
- return strlen(buf) + 1;
+ return sprintf(buf, "%lu\n", timer_data->delay_off);
}
-static ssize_t led_delay_off_store(struct device *dev,
+static ssize_t led_delay_off_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
count++;
if (count == size) {
- timer_data->delay_off = state;
- mod_timer(&timer_data->timer, jiffies + 1);
+ if (timer_data->delay_off != state) {
+ /* the new value differs from the previous */
+ timer_data->delay_off = state;
+
+ /* deactivate previous settings */
+ del_timer_sync(&timer_data->timer);
+
+ /* try to activate hardware acceleration, if any */
+ if (!led_cdev->blink_set ||
+ led_cdev->blink_set(led_cdev,
+ &timer_data->delay_on, &timer_data->delay_off)) {
+ /* no hardware acceleration, blink via timer */
+ mod_timer(&timer_data->timer, jiffies + 1);
+ }
+ }
ret = count;
}
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);
if (rc)
goto err_out_delayon;
+ /* If there is hardware support for blinking, start one
+ * user friendly blink rate chosen by the driver.
+ */
+ if (led_cdev->blink_set)
+ led_cdev->blink_set(led_cdev,
+ &timer_data->delay_on, &timer_data->delay_off);
+
return;
err_out_delayon: