[media] uvcvideo: Support allocating buffers larger than the current frame size

The queue_setup handler takes an optional format argument that can be
used to allocate buffers for a format different than the current format.
The uvcvideo driver doesn't support changing the format when buffers
have been allocated, but there's no reason not to support allocating
buffers larger than the minimum size.

When the format argument isn't NULL verify that the requested image size
is large enough for the current format and use it for the buffer size.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

diff --git a/drivers/media/usb/uvc/uvc_queue.c b/drivers/media/usb/uvc/uvc_queue.c
index 254bc346243e9af93a1483f3762b6ca367bd3dea..d46dd7011ed32fe68cd3fe373bacccfc3f0d9702 100644 (file)
--- a/drivers/media/usb/uvc/uvc_queue.c
+++ b/drivers/media/usb/uvc/uvc_queue.c
@@ -48,9 +48,14 @@ static int uvc_queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt,
        struct uvc_streaming *stream =
                        container_of(queue, struct uvc_streaming, queue);
 
+       /* Make sure the image size is large enough. */
+       if (fmt && fmt->fmt.pix.sizeimage < stream->ctrl.dwMaxVideoFrameSize)
+               return -EINVAL;
+
        *nplanes = 1;
 
-       sizes[0] = stream->ctrl.dwMaxVideoFrameSize;
+       sizes[0] = fmt ? fmt->fmt.pix.sizeimage
+                : stream->ctrl.dwMaxVideoFrameSize;
 
        return 0;
 }