[media] gspca - main: Fix the isochronous transfer interval

For USB speeds different of 'low', the bInterval value is logarithmic.

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

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/media/video/gspca/gspca.c b/drivers/media/video/gspca/gspca.c
index a3c2d36da0c8..85d24696db26 100644
--- a/drivers/media/video/gspca/gspca.c
+++ b/drivers/media/video/gspca/gspca.c
@@ -754,7 +754,10 @@ static int create_urbs(struct gspca_dev *gspca_dev,
                                                     ep->desc.bEndpointAddress);
                         urb->transfer_flags = URB_ISO_ASAP
                                         | URB_NO_TRANSFER_DMA_MAP;
-                        urb->interval = ep->desc.bInterval;
+                        if (gspca_dev->dev->speed == USB_SPEED_LOW)
+                                urb->interval = ep->desc.bInterval;
+                        else
+                                urb->interval = 1 << (ep->desc.bInterval - 1);
                         urb->complete = isoc_irq;
                         urb->number_of_packets = npkt;
                         for (i = 0; i < npkt; i++) {