media: gspca: support multiple pixel formats in TRY_FMT

If a driver supports multiple pixel formats with the same frame size,
TRY_FMT will currently always return the first pixel format.
Fix this by adding pixelformat support to wxh_to_nearest_mode().
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/usb/gspca/gspca.c

@@ -926,10 +926,16 @@ static int wxh_to_mode(struct gspca_dev *gspca_dev,
 }
 
 static int wxh_to_nearest_mode(struct gspca_dev *gspca_dev,
-			int width, int height)
+			int width, int height, u32 pixelformat)
 {
 	int i;
 
+	for (i = gspca_dev->cam.nmodes; --i > 0; ) {
+		if (width >= gspca_dev->cam.cam_mode[i].width
+		    && height >= gspca_dev->cam.cam_mode[i].height
+		    && pixelformat == gspca_dev->cam.cam_mode[i].pixelformat)
+			return i;
+	}
 	for (i = gspca_dev->cam.nmodes; --i > 0; ) {
 		if (width >= gspca_dev->cam.cam_mode[i].width
 		    && height >= gspca_dev->cam.cam_mode[i].height)
@@ -1059,7 +1065,7 @@ static int try_fmt_vid_cap(struct gspca_dev *gspca_dev,
 		    fmt->fmt.pix.pixelformat, w, h);
 
 	/* search the nearest mode for width and height */
-	mode = wxh_to_nearest_mode(gspca_dev, w, h);
+	mode = wxh_to_nearest_mode(gspca_dev, w, h, fmt->fmt.pix.pixelformat);
 
 	/* OK if right palette */
 	if (gspca_dev->cam.cam_mode[mode].pixelformat