Re: [PATCH 4/4] media: imx-media-capture: add frame sizes/interval enumeration

[Steve Longerbeam]

On 03/19/2017 03:49 AM, 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 <rmk+kernel@xxxxxxxxxxxxxxx>
> ---
>   drivers/staging/media/imx/imx-media-capture.c | 62 +++++++++++++++++++++++++++
>   1 file changed, 62 insertions(+)
>
> diff --git a/drivers/staging/media/imx/imx-media-capture.c b/drivers/staging/media/imx/imx-media-capture.c
> index cdeb2cd8b1d7..bc99d9310e36 100644
> --- a/drivers/staging/media/imx/imx-media-capture.c
> +++ b/drivers/staging/media/imx/imx-media-capture.c
> @@ -82,6 +82,65 @@ static int vidioc_querycap(struct file *file, void *fh,
>   	return 0;
>   }
>   
> +static int capture_enum_framesizes(struct file *file, void *fh,
> +				   struct v4l2_frmsizeenum *fsize)
> +{
> +	struct capture_priv *priv = video_drvdata(file);
> +	const struct imx_media_pixfmt *cc;
> +	struct v4l2_subdev_frame_size_enum fse = {
> +		.index = fsize->index,
> +		.pad = priv->src_sd_pad,
> +		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
> +	};
> +	int ret;
> +
> +	cc = imx_media_find_format(fsize->pixel_format, CS_SEL_ANY, true);
> +	if (!cc)
> +		return -EINVAL;
> +
> +	fse.code = cc->codes[0];
> +
> +	ret = v4l2_subdev_call(priv->src_sd, pad, enum_frame_size, NULL, &fse);
> +	if (ret)
> +		return ret;
> +
> +	fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
> +	fsize->discrete.width = fse.min_width;
> +	fsize->discrete.height = fse.max_height;
> +
> +	return 0;
> +}


The PRP ENC/VF subdevices will return a continuous range of
supported frame sizes at their source pad, so this should be
modified to:

...
    if (fse.min_width == fse.max_width &&
        fse.min_height == fse.max_height) {
        fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
        fsize->discrete.width = fse.min_width;
        fsize->discrete.height = fse.min_height;
    } else {
        fsize->type = V4L2_FRMSIZE_TYPE_CONTINUOUS;
        fsize->stepwise.min_width = fse.min_width;
        fsize->stepwise.max_width = fse.max_width;
        fsize->stepwise.min_height = fse.min_height;
        fsize->stepwise.max_height = fse.max_height;
        fsize->stepwise.step_width = 1;
        fsize->stepwise.step_height = 1;
    }
...

Steve


> +
> +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;
> +
> +	return 0;
> +}
> +
>   static int capture_enum_fmt_vid_cap(struct file *file, void *fh,
>   				    struct v4l2_fmtdesc *f)
>   {
> @@ -270,6 +329,9 @@ static int capture_s_parm(struct file *file, void *fh,
>   static const struct v4l2_ioctl_ops capture_ioctl_ops = {
>   	.vidioc_querycap	= vidioc_querycap,
>   
> +	.vidioc_enum_framesizes = capture_enum_framesizes,
> +	.vidioc_enum_frameintervals = capture_enum_frameintervals,
> +
>   	.vidioc_enum_fmt_vid_cap        = capture_enum_fmt_vid_cap,
>   	.vidioc_g_fmt_vid_cap           = capture_g_fmt_vid_cap,
>   	.vidioc_try_fmt_vid_cap         = capture_try_fmt_vid_cap,