[media] rc: do not wake up rc thread unless there is something to do

The TechnoTrend USB IR Receiver sends 125 ISO URBs per second, even when
there is no IR activity. Reduce the number of wake ups from the other
drivers too.

This saves about 0.25ms/s on a 2.4GHz Core 2 according to powertop.

Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/rc/fintek-cir.c b/drivers/media/rc/fintek-cir.c
index ab30c64..52fd769 100644
--- a/drivers/media/rc/fintek-cir.c
+++ b/drivers/media/rc/fintek-cir.c
@@ -295,6 +295,7 @@
 {
 	DEFINE_IR_RAW_EVENT(rawir);
 	u8 sample;
+	bool event = false;
 	int i;
 
 	for (i = 0; i < fintek->pkts; i++) {
@@ -332,7 +333,9 @@
 			fit_dbg("Storing %s with duration %d",
 				rawir.pulse ? "pulse" : "space",
 				rawir.duration);
-			ir_raw_event_store_with_filter(fintek->rdev, &rawir);
+			if (ir_raw_event_store_with_filter(fintek->rdev,
+									&rawir))
+				event = true;
 			break;
 		}
 
@@ -342,8 +345,10 @@
 
 	fintek->pkts = 0;
 
-	fit_dbg("Calling ir_raw_event_handle");
-	ir_raw_event_handle(fintek->rdev);
+	if (event) {
+		fit_dbg("Calling ir_raw_event_handle");
+		ir_raw_event_handle(fintek->rdev);
+	}
 }
 
 /* copy data from hardware rx register into driver buffer */