On 03/21/18 01:37, Steve Longerbeam wrote:
> Parse neighbor remote devices on the video muxes input ports, add them to a
> subdev notifier, and register the subdev notifier for the video mux, by
> calling v4l2_async_register_fwnode_subdev().
>
> Signed-off-by: Steve Longerbeam <[email protected]>
> ---
> Changes since v2:
> - none
> Changes since v1:
> - add #include <linux/slab.h> for kcalloc() declaration.
> ---
> drivers/media/platform/video-mux.c | 36 +++++++++++++++++++++++++++++++++++-
> 1 file changed, 35 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/platform/video-mux.c
> b/drivers/media/platform/video-mux.c
> index ee89ad7..b93b0af 100644
> --- a/drivers/media/platform/video-mux.c
> +++ b/drivers/media/platform/video-mux.c
> @@ -21,8 +21,10 @@
> #include <linux/of.h>
> #include <linux/of_graph.h>
> #include <linux/platform_device.h>
> +#include <linux/slab.h>
> #include <media/v4l2-async.h>
> #include <media/v4l2-device.h>
> +#include <media/v4l2-fwnode.h>
> #include <media/v4l2-subdev.h>
>
> struct video_mux {
> @@ -193,6 +195,38 @@ static const struct v4l2_subdev_ops video_mux_subdev_ops
> = {
> .video = &video_mux_subdev_video_ops,
> };
>
> +static int video_mux_parse_endpoint(struct device *dev,
> + struct v4l2_fwnode_endpoint *vep,
> + struct v4l2_async_subdev *asd)
> +{
> + /*
> + * it's not an error if remote is missing on a video-mux
> + * input port, return -ENOTCONN to skip this endpoint with
> + * no error.
> + */
> + return fwnode_device_is_available(asd->match.fwnode) ? 0 : -ENOTCONN;
> +}
> +
> +static int video_mux_async_register(struct video_mux *vmux,
> + unsigned int num_pads)
> +{
> + unsigned int i, *ports;
> + int ret;
> +
> + ports = kcalloc(num_pads - 1, sizeof(*ports), GFP_KERNEL);
> + if (!ports)
> + return -ENOMEM;
> + for (i = 0; i < num_pads - 1; i++)
> + ports[i] = i;
> +
> + ret = v4l2_async_register_fwnode_subdev(
> + &vmux->subdev, sizeof(struct v4l2_async_subdev),
> + ports, num_pads - 1, video_mux_parse_endpoint);
> +
> + kfree(ports);
> + return ret;
> +}
> +
> static int video_mux_probe(struct platform_device *pdev)
> {
> struct device_node *np = pdev->dev.of_node;
> @@ -258,7 +292,7 @@ static int video_mux_probe(struct platform_device *pdev)
>
> vmux->subdev.entity.ops = &video_mux_ops;
>
> - return v4l2_async_register_subdev(&vmux->subdev);
> + return video_mux_async_register(vmux, num_pads);
I would prefer to change the last argument to 'num_pads - 1' and drop the ' - 1'
part in the video_mux_async_register() function. Perhaps renaming the num_pads
argument there to num_input_pads.
Regards,
Hans
> }
>
> static int video_mux_remove(struct platform_device *pdev)
>
