Hi Russel,

On Sun, Mar 19, 2017 at 10:49:08AM +0000, Russell King wrote:

Add support for enumerating frame sizes and frame intervals from the
first subdev via the V4L2 interfaces.

Signed-off-by: Russell King <redacted>
---
 drivers/staging/media/imx/imx-media-capture.c | 62 +++++++++++++++++++++++++++
 1 file changed, 62 insertions(+)

...

+static int capture_enum_frameintervals(struct file *file, void *fh,
+				       struct v4l2_frmivalenum *fival)
+{
+	struct capture_priv *priv = video_drvdata(file);
+	const struct imx_media_pixfmt *cc;
+	struct v4l2_subdev_frame_interval_enum fie = {
+		.index = fival->index,
+		.pad = priv->src_sd_pad,
+		.width = fival->width,
+		.height = fival->height,
+		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
+	};
+	int ret;
+
+	cc = imx_media_find_format(fival->pixel_format, CS_SEL_ANY, true);
+	if (!cc)
+		return -EINVAL;
+
+	fie.code = cc->codes[0];
+
+	ret = v4l2_subdev_call(priv->src_sd, pad, enum_frame_interval, NULL, &fie);
+	if (ret)
+		return ret;
+
+	fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
+	fival->discrete = fie.interval;

For some parallel sensors (mine is a E2V ev76c560) "any" frame interval is possible,
and hence type should be V4L2_FRMIVAL_TYPE_CONTINUOUS.

see also https://www.spinics.net/lists/linux-media/msg98622.html,
https://patchwork.kernel.org/patch/9171201/ and
https://patchwork.kernel.org/patch/9171199/

Philippe

-- 
Philippe De Muyter +32 2 6101532 Macq SA rue de l'Aeronef 2 B-1140 Bruxelles