X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fleds%2Fledtrig-timer.c;h=5c99f4f0c69214f101a519c9c190d57aae64e317;hb=060856c799191ffc360105cac49f3f9e68d526b7;hp=ed9ff02c77ea742c23c616a0f340c400770c33ec;hpb=973ed7c49a5c2271a10ce54ac06bba5617fca3a8;p=linux-2.6-omap-h63xx.git

diff --git a/drivers/leds/ledtrig-timer.c b/drivers/leds/ledtrig-timer.c
index ed9ff02c77e..5c99f4f0c69 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);
@@ -52,7 +64,7 @@ static void led_timer_function(unsigned long data)
 	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);
@@ -63,7 +75,7 @@ static ssize_t led_delay_on_show(struct device *dev,
 	return strlen(buf) + 1;
 }
 
-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);
@@ -77,15 +89,28 @@ static ssize_t led_delay_on_store(struct device *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);
@@ -96,7 +121,7 @@ static ssize_t led_delay_off_show(struct device *dev,
 	return strlen(buf) + 1;
 }
 
-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);
@@ -110,8 +135,21 @@ static ssize_t led_delay_off_store(struct device *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;
 	}
 
@@ -130,6 +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);
@@ -143,6 +184,13 @@ static void timer_trig_activate(struct led_classdev *led_cdev)
 	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: