[BATTERY] Universal power supply class (was: battery class)

This class is result of "external power" and "battery" classes merge,
as suggested by David Woodhouse. He also implemented uevent support.

Here how userspace seeing it now:

    	# ls /sys/class/power\ supply/
    	ac  main-battery  usb

    	# cat /sys/class/power\ supply/ac/type
    	AC

    	# cat /sys/class/power\ supply/usb/type
    	USB

    	# cat /sys/class/power\ supply/main-battery/type
    	Battery

    	# cat /sys/class/power\ supply/ac/online
    	1

    	# cat /sys/class/power\ supply/usb/online
    	0

    	# cat /sys/class/power\ supply/main-battery/status
    	Charging

    	# cat /sys/class/leds/h5400\:red-left/trigger
    	none h5400-radio timer hwtimer ac-online usb-online
    	main-battery-charging-or-full [main-battery-charging]
    	main-battery-full

Signed-off-by: Anton Vorontsov <cbou@mail.ru>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
diff --git a/drivers/power/power_supply_leds.c b/drivers/power/power_supply_leds.c
new file mode 100644
index 0000000..7232490
--- /dev/null
+++ b/drivers/power/power_supply_leds.c
@@ -0,0 +1,176 @@
+/*
+ *  LEDs triggers for power supply class
+ *
+ *  Copyright © 2007  Anton Vorontsov <cbou@mail.ru>
+ *  Copyright © 2004  Szabolcs Gyurko
+ *  Copyright © 2003  Ian Molton <spyro@f2s.com>
+ *
+ *  Modified: 2004, Oct     Szabolcs Gyurko
+ *
+ *  You may use this code as per GPL version 2
+ */
+
+#include <linux/power_supply.h>
+
+/* Battery specific LEDs triggers. */
+
+static void power_supply_update_bat_leds(struct power_supply *psy)
+{
+	union power_supply_propval status;
+
+	if (psy->get_property(psy, POWER_SUPPLY_PROP_STATUS, &status))
+		return;
+
+	dev_dbg(psy->dev, "%s %d\n", __FUNCTION__, status.intval);
+
+	switch (status.intval) {
+	case POWER_SUPPLY_STATUS_FULL:
+		led_trigger_event(psy->charging_full_trig, LED_FULL);
+		led_trigger_event(psy->charging_trig, LED_OFF);
+		led_trigger_event(psy->full_trig, LED_FULL);
+		break;
+	case POWER_SUPPLY_STATUS_CHARGING:
+		led_trigger_event(psy->charging_full_trig, LED_FULL);
+		led_trigger_event(psy->charging_trig, LED_FULL);
+		led_trigger_event(psy->full_trig, LED_OFF);
+		break;
+	default:
+		led_trigger_event(psy->charging_full_trig, LED_OFF);
+		led_trigger_event(psy->charging_trig, LED_OFF);
+		led_trigger_event(psy->full_trig, LED_OFF);
+		break;
+	}
+
+	return;
+}
+
+static int power_supply_create_bat_triggers(struct power_supply *psy)
+{
+	int rc = 0;
+
+	psy->charging_full_trig_name = kmalloc(strlen(psy->name) +
+				  sizeof("-charging-or-full"), GFP_KERNEL);
+	if (!psy->charging_full_trig_name)
+		goto charging_full_failed;
+
+	psy->charging_trig_name = kmalloc(strlen(psy->name) +
+					  sizeof("-charging"), GFP_KERNEL);
+	if (!psy->charging_trig_name)
+		goto charging_failed;
+
+	psy->full_trig_name = kmalloc(strlen(psy->name) +
+				      sizeof("-full"), GFP_KERNEL);
+	if (!psy->full_trig_name)
+		goto full_failed;
+
+	strcpy(psy->charging_full_trig_name, psy->name);
+	strcat(psy->charging_full_trig_name, "-charging-or-full");
+	strcpy(psy->charging_trig_name, psy->name);
+	strcat(psy->charging_trig_name, "-charging");
+	strcpy(psy->full_trig_name, psy->name);
+	strcat(psy->full_trig_name, "-full");
+
+	led_trigger_register_simple(psy->charging_full_trig_name,
+				    &psy->charging_full_trig);
+	led_trigger_register_simple(psy->charging_trig_name,
+				    &psy->charging_trig);
+	led_trigger_register_simple(psy->full_trig_name,
+				    &psy->full_trig);
+
+	goto success;
+
+full_failed:
+	kfree(psy->charging_trig_name);
+charging_failed:
+	kfree(psy->charging_full_trig_name);
+charging_full_failed:
+	rc = -ENOMEM;
+success:
+	return rc;
+}
+
+static void power_supply_remove_bat_triggers(struct power_supply *psy)
+{
+	led_trigger_unregister_simple(psy->charging_full_trig);
+	led_trigger_unregister_simple(psy->charging_trig);
+	led_trigger_unregister_simple(psy->full_trig);
+	kfree(psy->full_trig_name);
+	kfree(psy->charging_trig_name);
+	kfree(psy->charging_full_trig_name);
+	return;
+}
+
+/* Generated power specific LEDs triggers. */
+
+static void power_supply_update_gen_leds(struct power_supply *psy)
+{
+	union power_supply_propval online;
+
+	if (psy->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &online))
+		return;
+
+	dev_dbg(psy->dev, "%s %d\n", __FUNCTION__, online.intval);
+
+	if (online.intval)
+		led_trigger_event(psy->online_trig, LED_FULL);
+	else
+		led_trigger_event(psy->online_trig, LED_OFF);
+
+	return;
+}
+
+static int power_supply_create_gen_triggers(struct power_supply *psy)
+{
+	int rc = 0;
+
+	psy->online_trig_name = kmalloc(strlen(psy->name) + sizeof("-online"),
+					GFP_KERNEL);
+	if (!psy->online_trig_name)
+		goto online_failed;
+
+	strcpy(psy->online_trig_name, psy->name);
+	strcat(psy->online_trig_name, "-online");
+
+	led_trigger_register_simple(psy->online_trig_name, &psy->online_trig);
+
+	goto success;
+
+online_failed:
+	rc = -ENOMEM;
+success:
+	return rc;
+}
+
+static void power_supply_remove_gen_triggers(struct power_supply *psy)
+{
+	led_trigger_unregister_simple(psy->online_trig);
+	kfree(psy->online_trig_name);
+	return;
+}
+
+/* Choice what triggers to create&update. */
+
+void power_supply_update_leds(struct power_supply *psy)
+{
+	if (psy->type == POWER_SUPPLY_TYPE_BATTERY)
+		power_supply_update_bat_leds(psy);
+	else
+		power_supply_update_gen_leds(psy);
+	return;
+}
+
+int power_supply_create_triggers(struct power_supply *psy)
+{
+	if (psy->type == POWER_SUPPLY_TYPE_BATTERY)
+		return power_supply_create_bat_triggers(psy);
+	return power_supply_create_gen_triggers(psy);
+}
+
+void power_supply_remove_triggers(struct power_supply *psy)
+{
+	if (psy->type == POWER_SUPPLY_TYPE_BATTERY)
+		power_supply_remove_bat_triggers(psy);
+	else
+		power_supply_remove_gen_triggers(psy);
+	return;
+}