[RFKILL]: Add support for an rfkill LED.

This adds a LED trigger.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/rfkill.h b/include/linux/rfkill.h
index d76397c..26fddea 100644
--- a/include/linux/rfkill.h
+++ b/include/linux/rfkill.h
@@ -26,6 +26,7 @@
 #include <linux/list.h>
 #include <linux/mutex.h>
 #include <linux/device.h>
+#include <linux/leds.h>
 
 /**
  * enum rfkill_type - type of rfkill switch.
@@ -56,6 +57,7 @@
  * @data: Pointer to the RF button drivers private data which will be
  *	passed along when toggling radio state.
  * @toggle_radio(): Mandatory handler to control state of the radio.
+ * @led_trigger: A LED trigger for this button's LED.
  * @dev: Device structure integrating the switch into device tree.
  * @node: Used to place switch into list of all switches known to the
  *	the system.
@@ -74,6 +76,10 @@
 	void *data;
 	int (*toggle_radio)(void *data, enum rfkill_state state);
 
+#ifdef CONFIG_RFKILL_LEDS
+	struct led_trigger led_trigger;
+#endif
+
 	struct device dev;
 	struct list_head node;
 };
@@ -84,4 +90,19 @@
 int rfkill_register(struct rfkill *rfkill);
 void rfkill_unregister(struct rfkill *rfkill);
 
+/**
+ * rfkill_get_led_name - Get the LED trigger name for the button's LED.
+ * This function might return a NULL pointer if registering of the
+ * LED trigger failed.
+ * Use this as "default_trigger" for the LED.
+ */
+static inline char *rfkill_get_led_name(struct rfkill *rfkill)
+{
+#ifdef CONFIG_RFKILL_LEDS
+	return (char *)(rfkill->led_trigger.name);
+#else
+	return NULL;
+#endif
+}
+
 #endif /* RFKILL_H */