Re: [PATCH v4 1/3] media: v4l2-dev.c: Add Meta: to the name of metadata devices

[Yunke Cao <yunkec@chromium.org>]

On Sat, Dec 3, 2022 at 2:08 AM Ricardo Ribalda <ribalda@chromium.org> wrote:
>
> Devices with Metadata output (like uvc), create two video devices, one
> for the data itself and another one for the metadata.
>
> Add a "Meta: " to the beginning of the device name, as suggested by Mauro,
> to avoid having multiple devices with the same name.
>
> Fixes v4l2-compliance:
> Media Controller ioctls:
>      fail: v4l2-test-media.cpp(205): v2_entity_names_set.find(key) != v2_entity_names_set.end()
>    test MEDIA_IOC_G_TOPOLOGY: FAIL
>      fail: v4l2-test-media.cpp(394): num_data_links != num_links
>    test MEDIA_IOC_ENUM_ENTITIES/LINKS: FAIL
>
> Suggested-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
> ---
>  drivers/media/v4l2-core/v4l2-dev.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
>
> diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
> index 397d553177fa..5c2c9ebb6b96 100644
> --- a/drivers/media/v4l2-core/v4l2-dev.c
> +++ b/drivers/media/v4l2-core/v4l2-dev.c
> @@ -901,6 +901,15 @@ int __video_register_device(struct video_device *vdev,
>         if (WARN_ON(type != VFL_TYPE_SUBDEV && !vdev->device_caps))
>                 return -EINVAL;
>
> +       /* Add Meta: to metadata device names */
> +       if (vdev->device_caps &
> +           (V4L2_CAP_META_CAPTURE | V4L2_CAP_META_OUTPUT)) {
> +               char aux[sizeof(vdev->name)];
> +
> +               snprintf(aux, sizeof(aux), "Meta: %s", vdev->name);
> +               strscpy(vdev->name, aux, sizeof(aux));
> +       }
> +
>         /* v4l2_fh support */
>         spin_lock_init(&vdev->fh_lock);
>         INIT_LIST_HEAD(&vdev->fh_list);
>
> --
> 2.39.0.rc0.267.gcb52ba06e7-goog-b4-0.11.0-dev-696ae

Reviewed-by: Yunke Cao <yunkec@chromium.org>