HelenOS sources

LED_DEV_IFACE      92 uspace/drv/hid/usbhid/blink1/blink1.c 	.interfaces[LED_DEV_IFACE] = &usb_blink1_iface
LED_DEV_IFACE      45 uspace/lib/device/src/device/led_dev.c 	aid_t req = async_send_2(exch, DEV_IFACE_ID(LED_DEV_IFACE),
LED_DEV_IFACE      71 uspace/lib/drv/generic/dev_iface.c 		[LED_DEV_IFACE] = &remote_led_dev_iface,
HelenOS homepage, sources at GitHub