media: rcar-vin: Do not enumerate unsupported pixel formats

If a pixel format is not supported by the hardware NULL is returned by
rvin_format_from_pixel() for that fourcc. Verify that the pixel format
is supported using this or skip it when enumerating.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/rcar-vin/rcar-v4l2.c

@@ -296,12 +296,22 @@ static int rvin_g_fmt_vid_cap(struct file *file, void *priv,
 static int rvin_enum_fmt_vid_cap(struct file *file, void *priv,
 				 struct v4l2_fmtdesc *f)
 {
-	if (f->index >= ARRAY_SIZE(rvin_formats))
-		return -EINVAL;
-
-	f->pixelformat = rvin_formats[f->index].fourcc;
+	struct rvin_dev *vin = video_drvdata(file);
+	unsigned int i;
+	int matched;
+
+	matched = -1;
+	for (i = 0; i < ARRAY_SIZE(rvin_formats); i++) {
+		if (rvin_format_from_pixel(vin, rvin_formats[i].fourcc))
+			matched++;
+
+		if (matched == f->index) {
+			f->pixelformat = rvin_formats[i].fourcc;
+			return 0;
+		}
+	}
 
-	return 0;
+	return -EINVAL;
 }
 
 static int rvin_g_selection(struct file *file, void *fh,