diff --git a/main/devicestate.c b/main/devicestate.c index 9a2881a3ff..b27413cfb2 100644 --- a/main/devicestate.c +++ b/main/devicestate.c @@ -476,12 +476,21 @@ int ast_devstate_changed_literal(enum ast_device_state state, const char *device { struct state_change *change; - /* If we know the state change (how nice of the caller of this function!) - * then we can just generate the event. Otherwise, we have to go through - * a crap ton of extra work to go figure out what the state change is. - * We queue the fact that the state has changed up for another thread to - * go figure out, which it does by calling into the channel driver if it - * can, or by walking through the active channel list. */ + /* + * If we know the state change (how nice of the caller of this function!) + * then we can just generate a device state event. + * + * Otherwise, we do the following: + * - Queue an event up to another thread that the state has changed + * - In the processing thread, it calls the callback provided by the + * device state provider (which may or may not be a channel driver) + * to determine the state. + * - If the device state provider does not know the state, or this is + * for a channel and the channel driver does not implement a device + * state callback, then we will look through the channel list to + * see if we can determine a state based on active calls. + * - Once a state has been determined, a device state event is generated. + */ if (state != AST_DEVICE_UNKNOWN) { devstate_event(device, state);