[media] uvcvideo: Fix bytesperline calculation for planar YUV

The formula used to calculate bytesperline only works for packed format.
So far, all planar format we support have their bytesperline equal to
the image width (stride of the Y plane or a line of Y for M420).

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/usb/uvc/uvc_v4l2.c

@@ -142,6 +142,21 @@ static __u32 uvc_try_frame_interval(struct uvc_frame *frame, __u32 interval)
 	return interval;
 }
 
+static __u32 uvc_v4l2_get_bytesperline(const struct uvc_format *format,
+	const struct uvc_frame *frame)
+{
+	switch (format->fcc) {
+	case V4L2_PIX_FMT_NV12:
+	case V4L2_PIX_FMT_YVU420:
+	case V4L2_PIX_FMT_YUV420:
+	case V4L2_PIX_FMT_M420:
+		return frame->wWidth;
+
+	default:
+		return format->bpp * frame->wWidth / 8;
+	}
+}
+
 static int uvc_v4l2_try_format(struct uvc_streaming *stream,
 	struct v4l2_format *fmt, struct uvc_streaming_control *probe,
 	struct uvc_format **uvc_format, struct uvc_frame **uvc_frame)
@@ -245,7 +260,7 @@ static int uvc_v4l2_try_format(struct uvc_streaming *stream,
 	fmt->fmt.pix.width = frame->wWidth;
 	fmt->fmt.pix.height = frame->wHeight;
 	fmt->fmt.pix.field = V4L2_FIELD_NONE;
-	fmt->fmt.pix.bytesperline = format->bpp * frame->wWidth / 8;
+	fmt->fmt.pix.bytesperline = uvc_v4l2_get_bytesperline(format, frame);
 	fmt->fmt.pix.sizeimage = probe->dwMaxVideoFrameSize;
 	fmt->fmt.pix.colorspace = format->colorspace;
 	fmt->fmt.pix.priv = 0;
@@ -282,7 +297,7 @@ static int uvc_v4l2_get_format(struct uvc_streaming *stream,
 	fmt->fmt.pix.width = frame->wWidth;
 	fmt->fmt.pix.height = frame->wHeight;
 	fmt->fmt.pix.field = V4L2_FIELD_NONE;
-	fmt->fmt.pix.bytesperline = format->bpp * frame->wWidth / 8;
+	fmt->fmt.pix.bytesperline = uvc_v4l2_get_bytesperline(format, frame);
 	fmt->fmt.pix.sizeimage = stream->ctrl.dwMaxVideoFrameSize;
 	fmt->fmt.pix.colorspace = format->colorspace;
 	fmt->fmt.pix.priv = 0;