V4L/DVB (9545): gspca: Add a flag for empty ISOC packets.

- This flag is needed by some subdrivers as tv8532 for start
  of frame detection.

Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/media/video/gspca/gspca.c b/drivers/media/video/gspca/gspca.c
index afddb18024a8..8a528c97aae0 100644
--- a/drivers/media/video/gspca/gspca.c
+++ b/drivers/media/video/gspca/gspca.c
@@ -150,8 +150,11 @@ static void fill_frame(struct gspca_dev *gspca_dev,
 
                 /* check the packet status and length */
                 len = urb->iso_frame_desc[i].actual_length;
-                if (len == 0)
+                if (len == 0) {
+                        if (gspca_dev->empty_packet == 0)
+                                gspca_dev->empty_packet = 1;
                         continue;
+                }
                 st = urb->iso_frame_desc[i].status;
                 if (st) {
                         PDEBUG(D_ERR,
@@ -1858,6 +1861,7 @@ int gspca_dev_probe(struct usb_interface *intf,
         gspca_dev->nbalt = intf->num_altsetting;
         gspca_dev->sd_desc = sd_desc;
         gspca_dev->nbufread = 2;
+        gspca_dev->empty_packet = -1;   /* don't check the empty packets */
 
         /* configure the subdriver and initialize the USB device */
         ret = gspca_dev->sd_desc->config(gspca_dev, id);