V4L/DVB (8067): cx18: Fix firmware load for case when digital capture happens first

This is a fix for the case when a digital capture from dvr0 happens first after
modprobe, before access to any cx18 v4l2 device nodes.  The initial dvb feed
start has been changed to load the firmware if not already loaded.  Also fixed a
use counter to correct dvb feed accounting if starting the transport DMA fails.
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/video/cx18/cx18-dvb.c

@@ -69,11 +69,21 @@ static int cx18_dvb_start_feed(struct dvb_demux_feed *feed)
 	struct dvb_demux *demux = feed->demux;
 	struct cx18_stream *stream = (struct cx18_stream *) demux->priv;
 	struct cx18 *cx = stream->cx;
-	int ret = -EINVAL;
+	int ret;
 	u32 v;
 
 	CX18_DEBUG_INFO("Start feed: pid = 0x%x index = %d\n",
 			feed->pid, feed->index);
+
+	mutex_lock(&cx->serialize_lock);
+	ret = cx18_init_on_first_open(cx);
+	mutex_unlock(&cx->serialize_lock);
+	if (ret) {
+		CX18_ERR("Failed to initialize firmware starting DVB feed\n");
+		return ret;
+	}
+	ret = -EINVAL;
+
 	switch (cx->card->type) {
 	case CX18_CARD_HVR_1600_ESMT:
 	case CX18_CARD_HVR_1600_SAMSUNG:
@@ -101,6 +111,11 @@ static int cx18_dvb_start_feed(struct dvb_demux_feed *feed)
 		if (stream->dvb.feeding++ == 0) {
 			CX18_DEBUG_INFO("Starting Transport DMA\n");
 			ret = cx18_start_v4l2_encode_stream(stream);
+			if (ret < 0) {
+				CX18_DEBUG_INFO(
+					"Failed to start Transport DMA\n");
+				stream->dvb.feeding--;
+			}
 		} else
 			ret = 0;
 		mutex_unlock(&stream->dvb.feedlock);