usb: gadget: f_uvc: Fix SuperSpeed companion descriptor's wBytesPerInterval

commit 09424c50b7dff40cb30011c09114404a4656e023 upstream.

The streaming_maxburst module parameter is 0 offset (0..15)
so we must add 1 while using it for wBytesPerInterval
calculation for the SuperSpeed companion descriptor.

Without this host uvcvideo driver will always see the wrong
wBytesPerInterval for SuperSpeed uvc gadget and may not find
a suitable video interface endpoint.
e.g. for streaming_maxburst = 0 case it will always
fail as wBytePerInterval was evaluating to 0.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c
index 29b41b5..c7689d0 100644 (file)
--- a/drivers/usb/gadget/function/f_uvc.c
+++ b/drivers/usb/gadget/function/f_uvc.c
@@ -625,7 +625,7 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
        uvc_ss_streaming_comp.bMaxBurst = opts->streaming_maxburst;
        uvc_ss_streaming_comp.wBytesPerInterval =
                cpu_to_le16(max_packet_size * max_packet_mult *
-                           opts->streaming_maxburst);
+                           (opts->streaming_maxburst + 1));
 
        /* Allocate endpoints. */
        ep = usb_ep_autoconfig(cdev->gadget, &uvc_control_ep);