V4L/DVB (12075): gspca_ov519: check ov518 packet numbers
Check ov518 packet numbers to detect dropped packets.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/gspca/ov519.c b/drivers/media/video/gspca/ov519.c
index 55db32c..c298213 100644
--- a/drivers/media/video/gspca/ov519.c
+++ b/drivers/media/video/gspca/ov519.c
@@ -50,6 +50,8 @@
struct sd {
struct gspca_dev gspca_dev; /* !! must be the first item */
+ __u8 packet_nr;
+
char bridge;
#define BRIDGE_OV511 0
#define BRIDGE_OV511PLUS 1
@@ -2391,18 +2393,33 @@
__u8 *data, /* isoc packet */
int len) /* iso packet length */
{
- PDEBUG(D_STREAM, "ov518_pkt_scan: %d bytes", len);
-
- if (len & 7) {
- len--;
- PDEBUG(D_STREAM, "packet number: %d\n", (int)data[len]);
- }
+ struct sd *sd = (struct sd *) gspca_dev;
/* A false positive here is likely, until OVT gives me
* the definitive SOF/EOF format */
if ((!(data[0] | data[1] | data[2] | data[3] | data[5])) && data[6]) {
gspca_frame_add(gspca_dev, LAST_PACKET, frame, data, 0);
gspca_frame_add(gspca_dev, FIRST_PACKET, frame, data, 0);
+ sd->packet_nr = 0;
+ }
+
+ if (gspca_dev->last_packet_type == DISCARD_PACKET)
+ return;
+
+ /* Does this device use packet numbers ? */
+ if (len & 7) {
+ len--;
+ if (sd->packet_nr == data[len])
+ sd->packet_nr++;
+ /* The last few packets of the frame (which are all 0's
+ except that they may contain part of the footer), are
+ numbered 0 */
+ else if (sd->packet_nr == 0 || data[len]) {
+ PDEBUG(D_ERR, "Invalid packet nr: %d (expect: %d)",
+ (int)data[len], (int)sd->packet_nr);
+ gspca_dev->last_packet_type = DISCARD_PACKET;
+ return;
+ }
}
/* intermediate packet */