V4L/DVB (9801): cx18: Allow more than 63 capture buffers in rotation per stream

cx18: Allow more than 63 capture buffers in rotation per stream.  Implement
q_busy to hold buffers the firmware has for use.  q_free holds truly unused
buffers in a pool.  New buffers are given to the firmware as soon as the
firmware returns one, if there are any to give to the firmware.

Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/cx18/cx18-queue.h b/drivers/media/video/cx18/cx18-queue.h
index d184e55..456cec3 100644
--- a/drivers/media/video/cx18/cx18-queue.h
+++ b/drivers/media/video/cx18/cx18-queue.h
@@ -43,21 +43,21 @@
 void cx18_buf_swap(struct cx18_buffer *buf);
 
 /* cx18_queue utility functions */
-void _cx18_enqueue(struct cx18_stream *s, struct cx18_buffer *buf,
-		   struct cx18_queue *q, int to_front);
+struct cx18_queue *_cx18_enqueue(struct cx18_stream *s, struct cx18_buffer *buf,
+				 struct cx18_queue *q, int to_front);
 
 static inline
-void cx18_enqueue(struct cx18_stream *s, struct cx18_buffer *buf,
-		  struct cx18_queue *q)
+struct cx18_queue *cx18_enqueue(struct cx18_stream *s, struct cx18_buffer *buf,
+				struct cx18_queue *q)
 {
-	_cx18_enqueue(s, buf, q, 0); /* FIFO */
+	return _cx18_enqueue(s, buf, q, 0); /* FIFO */
 }
 
 static inline
-void cx18_push(struct cx18_stream *s, struct cx18_buffer *buf,
-	       struct cx18_queue *q)
+struct cx18_queue *cx18_push(struct cx18_stream *s, struct cx18_buffer *buf,
+			     struct cx18_queue *q)
 {
-	_cx18_enqueue(s, buf, q, 1); /* LIFO */
+	return _cx18_enqueue(s, buf, q, 1); /* LIFO */
 }
 
 void cx18_queue_init(struct cx18_queue *q);