ledtrig-sleep: Add led trigger for sleep debugging.

Signed-off-by: Brian Swetland <swetland@google.com>
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index ff4b8cf..ef2ddd4 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -468,6 +468,12 @@
 	  This allows LEDs to be initialised in the ON state.
 	  If unsure, say Y.
 
+config LEDS_TRIGGER_SLEEP
+	tristate "LED Sleep Mode Trigger"
+	depends on LEDS_TRIGGERS && HAS_EARLYSUSPEND
+	help
+	  This turns LEDs on when the screen is off but the cpu still running.
+
 comment "iptables trigger is under Netfilter config (LED target)"
 	depends on LEDS_TRIGGERS
 
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 890481c..9d3b109 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -56,3 +56,4 @@
 obj-$(CONFIG_LEDS_TRIGGER_BACKLIGHT)	+= ledtrig-backlight.o
 obj-$(CONFIG_LEDS_TRIGGER_GPIO)		+= ledtrig-gpio.o
 obj-$(CONFIG_LEDS_TRIGGER_DEFAULT_ON)	+= ledtrig-default-on.o
+obj-$(CONFIG_LEDS_TRIGGER_SLEEP)	+= ledtrig-sleep.o
diff --git a/drivers/leds/ledtrig-sleep.c b/drivers/leds/ledtrig-sleep.c
new file mode 100644
index 0000000..f164042
--- /dev/null
+++ b/drivers/leds/ledtrig-sleep.c
@@ -0,0 +1,80 @@
+/* drivers/leds/ledtrig-sleep.c
+ *
+ * Copyright (C) 2007 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/earlysuspend.h>
+#include <linux/leds.h>
+#include <linux/suspend.h>
+
+static int ledtrig_sleep_pm_callback(struct notifier_block *nfb,
+					unsigned long action,
+					void *ignored);
+
+DEFINE_LED_TRIGGER(ledtrig_sleep)
+static struct notifier_block ledtrig_sleep_pm_notifier = {
+	.notifier_call = ledtrig_sleep_pm_callback,
+	.priority = 0,
+};
+
+static void ledtrig_sleep_early_suspend(struct early_suspend *h)
+{
+	led_trigger_event(ledtrig_sleep, LED_FULL);
+}
+
+static void ledtrig_sleep_early_resume(struct early_suspend *h)
+{
+	led_trigger_event(ledtrig_sleep, LED_OFF);
+}
+
+static struct early_suspend ledtrig_sleep_early_suspend_handler = {
+	.suspend = ledtrig_sleep_early_suspend,
+	.resume = ledtrig_sleep_early_resume,
+};
+
+static int ledtrig_sleep_pm_callback(struct notifier_block *nfb,
+					unsigned long action,
+					void *ignored)
+{
+	switch (action) {
+	case PM_HIBERNATION_PREPARE:
+	case PM_SUSPEND_PREPARE:
+		led_trigger_event(ledtrig_sleep, LED_OFF);
+		return NOTIFY_OK;
+	case PM_POST_HIBERNATION:
+	case PM_POST_SUSPEND:
+		led_trigger_event(ledtrig_sleep, LED_FULL);
+		return NOTIFY_OK;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int __init ledtrig_sleep_init(void)
+{
+	led_trigger_register_simple("sleep", &ledtrig_sleep);
+	register_pm_notifier(&ledtrig_sleep_pm_notifier);
+	register_early_suspend(&ledtrig_sleep_early_suspend_handler);
+	return 0;
+}
+
+static void __exit ledtrig_sleep_exit(void)
+{
+	unregister_early_suspend(&ledtrig_sleep_early_suspend_handler);
+	unregister_pm_notifier(&ledtrig_sleep_pm_notifier);
+	led_trigger_unregister_simple(ledtrig_sleep);
+}
+
+module_init(ledtrig_sleep_init);
+module_exit(ledtrig_sleep_exit);
+