1 /* 2 * LED Triggers for USB Activity 3 * 4 * Copyright 2014 Michal Sojka <sojka@merica.cz> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 * 10 */ 11 12 #include <linux/module.h> 13 #include <linux/kernel.h> 14 #include <linux/init.h> 15 #include <linux/leds.h> 16 #include <linux/usb.h> 17 18 #define BLINK_DELAY 30 19 20 static unsigned long usb_blink_delay = BLINK_DELAY; 21 22 DEFINE_LED_TRIGGER(ledtrig_usb_gadget); 23 DEFINE_LED_TRIGGER(ledtrig_usb_host); 24 25 void usb_led_activity(enum usb_led_event ev) 26 { 27 struct led_trigger *trig = NULL; 28 29 switch (ev) { 30 case USB_LED_EVENT_GADGET: 31 trig = ledtrig_usb_gadget; 32 break; 33 case USB_LED_EVENT_HOST: 34 trig = ledtrig_usb_host; 35 break; 36 } 37 /* led_trigger_blink_oneshot() handles trig == NULL gracefully */ 38 led_trigger_blink_oneshot(trig, &usb_blink_delay, &usb_blink_delay, 0); 39 } 40 EXPORT_SYMBOL_GPL(usb_led_activity); 41 42 43 static int __init ledtrig_usb_init(void) 44 { 45 led_trigger_register_simple("usb-gadget", &ledtrig_usb_gadget); 46 led_trigger_register_simple("usb-host", &ledtrig_usb_host); 47 return 0; 48 } 49 50 static void __exit ledtrig_usb_exit(void) 51 { 52 led_trigger_unregister_simple(ledtrig_usb_gadget); 53 led_trigger_unregister_simple(ledtrig_usb_host); 54 } 55 56 module_init(ledtrig_usb_init); 57 module_exit(ledtrig_usb_exit); 58