[media] em28xx: rename function em28xx_isoc_copy_vbi and extend for USB bulk transfers

The URB data processing for bulk transfers is very similar to what
is done with isoc transfers, so create a common function that works
with both transfer types based on the existing isoc function.

[mchehab@redhat.com: Fix a CodingStyle issue: don't break strings
 into separate lines]
Signed-off-by: Frank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/usb/em28xx/em28xx-video.c

@@ -518,18 +518,16 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb)
 	return rc;
 }
 
-/* Version of isoc handler that takes into account a mixture of video and
-   VBI data */
-static inline int em28xx_isoc_copy_vbi(struct em28xx *dev, struct urb *urb)
+/* Version of the urb data handler that takes into account a mixture of
+   video and VBI data */
+static inline int em28xx_urb_data_copy_vbi(struct em28xx *dev, struct urb *urb)
 {
 	struct em28xx_buffer    *buf, *vbi_buf;
 	struct em28xx_dmaqueue  *dma_q = &dev->vidq;
 	struct em28xx_dmaqueue  *vbi_dma_q = &dev->vbiq;
-	unsigned char *outp = NULL;
-	unsigned char *vbioutp = NULL;
-	int i, len = 0, rc = 1;
-	unsigned char *p;
-	int vbi_size;
+	int xfer_bulk, vbi_size, num_packets, i, rc = 1;
+	unsigned int actual_length, len = 0;
+	unsigned char *p, *outp = NULL, *vbioutp = NULL;
 
 	if (!dev)
 		return 0;
@@ -540,6 +538,8 @@ static inline int em28xx_isoc_copy_vbi(struct em28xx *dev, struct urb *urb)
 	if (urb->status < 0)
 		print_err_status(dev, -1, urb->status);
 
+	xfer_bulk = usb_pipebulk(urb->pipe);
+
 	buf = dev->usb_ctl.vid_buf;
 	if (buf != NULL)
 		outp = videobuf_to_vmalloc(&buf->vb);
@@ -548,27 +548,39 @@ static inline int em28xx_isoc_copy_vbi(struct em28xx *dev, struct urb *urb)
 	if (vbi_buf != NULL)
 		vbioutp = videobuf_to_vmalloc(&vbi_buf->vb);
 
-	for (i = 0; i < urb->number_of_packets; i++) {
-		int status = urb->iso_frame_desc[i].status;
+	if (xfer_bulk) /* bulk */
+		num_packets = 1;
+	else /* isoc */
+		num_packets = urb->number_of_packets;
 
-		if (status < 0) {
-			print_err_status(dev, i, status);
+	for (i = 0; i < num_packets; i++) {
+		if (xfer_bulk) { /* bulk */
+			actual_length = urb->actual_length;
+
+			p = urb->transfer_buffer;
+		} else { /* isoc */
+			if (urb->iso_frame_desc[i].status < 0) {
+				print_err_status(dev, i,
+						 urb->iso_frame_desc[i].status);
 				if (urb->iso_frame_desc[i].status != -EPROTO)
 					continue;
 			}
 
-		len = urb->iso_frame_desc[i].actual_length;
-		if (urb->iso_frame_desc[i].actual_length <= 0) {
-			/* em28xx_isocdbg("packet %d is empty",i); - spammy */
-			continue;
-		}
-		if (urb->iso_frame_desc[i].actual_length >
-						dev->max_pkt_size) {
+			actual_length = urb->iso_frame_desc[i].actual_length;
+			if (actual_length > dev->max_pkt_size) {
 				em28xx_isocdbg("packet bigger than packet size");
 				continue;
 			}
 
-		p = urb->transfer_buffer + urb->iso_frame_desc[i].offset;
+			p = urb->transfer_buffer +
+			    urb->iso_frame_desc[i].offset;
+		}
+
+		if (actual_length <= 0) {
+			/* NOTE: happens very often with isoc transfers */
+			/* em28xx_usbdbg("packet %d is empty",i); - spammy */
+			continue;
+		}
 
 		/* capture type 0 = vbi start
 		   capture type 1 = video start
@@ -579,16 +591,20 @@ static inline int em28xx_isoc_copy_vbi(struct em28xx *dev, struct urb *urb)
 			em28xx_isocdbg("VBI START HEADER!!!\n");
 			dev->cur_field = p[2];
 			p += 4;
-			len -= 4;
+			len = actual_length - 4;
 		} else if (p[0] == 0x88 && p[1] == 0x88 &&
 			   p[2] == 0x88 && p[3] == 0x88) {
 			/* continuation */
 			p += 4;
-			len -= 4;
+			len = actual_length - 4;
 		} else if (p[0] == 0x22 && p[1] == 0x5a) {
 			/* start video */
 			p += 4;
-			len -= 4;
+			len = actual_length - 4;
+		} else {
+			/* NOTE: With bulk transfers, intermediate data packets
+			 * have no continuation header */
+			len = actual_length;
 		}
 
 		vbi_size = dev->vbi_width * dev->vbi_height;
@@ -776,7 +792,7 @@ buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
 						  EM28XX_NUM_BUFS,
 						  dev->max_pkt_size,
 						  EM28XX_NUM_ISOC_PACKETS,
-						  em28xx_isoc_copy_vbi);
+						  em28xx_urb_data_copy_vbi);
 		else
 			rc = em28xx_init_usb_xfer(dev, EM28XX_ANALOG_MODE, 0,
 						  EM28XX_NUM_BUFS,