Re: [PATCH v8 3/5] media: uvcvideo: Introduce dev->meta_formats

[Hans de Goede <hansg@kernel.org>]

Hi,

On 7-Jul-25 8:34 PM, Ricardo Ribalda wrote:
> Right now, there driver supports devices with one or two metadata
> formats. Prepare it to support more than two metadata formats.
> 
> This is achieved with the introduction of a new field `meta_formats`,
> that contains the array of metadata formats supported by the device, in
> the order expected by userspace.
> 
> Suggested-by: Hans de Goede <hansg@kernel.org>
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>

Thanks, patch looks good to me:

Reviewed-by: Hans de Goede <hansg@kernel.org>

Regards,

Hans



> ---
>  drivers/media/usb/uvc/uvc_driver.c   |  2 ++
>  drivers/media/usb/uvc/uvc_metadata.c | 38 +++++++++++++++++++++++++++++-------
>  drivers/media/usb/uvc/uvcvideo.h     |  6 ++++++
>  3 files changed, 39 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c
> index 62eb45435d8bec5c955720ecb46fb8936871e6cc..56ea20eeb7b9d5d92f3d837c15bdf11d536e9f2d 100644
> --- a/drivers/media/usb/uvc/uvc_driver.c
> +++ b/drivers/media/usb/uvc/uvc_driver.c
> @@ -2315,6 +2315,8 @@ static int uvc_probe(struct usb_interface *intf,
>  		goto error;
>  	}
>  
> +	uvc_meta_init(dev);
> +
>  	if (dev->quirks & UVC_QUIRK_NO_RESET_RESUME)
>  		udev->quirks &= ~USB_QUIRK_RESET_RESUME;
>  
> diff --git a/drivers/media/usb/uvc/uvc_metadata.c b/drivers/media/usb/uvc/uvc_metadata.c
> index 82de7781f5b6b70c5ba16bcba9e0741231231904..4bcbc22f47e67c52baf6e133f240131ff3d32a03 100644
> --- a/drivers/media/usb/uvc/uvc_metadata.c
> +++ b/drivers/media/usb/uvc/uvc_metadata.c
> @@ -64,14 +64,20 @@ static int uvc_meta_v4l2_try_format(struct file *file, void *fh,
>  	struct uvc_device *dev = stream->dev;
>  	struct v4l2_meta_format *fmt = &format->fmt.meta;
>  	u32 fmeta = fmt->dataformat;
> +	u32 i;
>  
>  	if (format->type != vfh->vdev->queue->type)
>  		return -EINVAL;
>  
> +	for (i = 0; (fmeta != dev->meta_formats[i]) && dev->meta_formats[i];
> +	     i++)
> +		;
> +	if (!dev->meta_formats[i])
> +		fmeta = V4L2_META_FMT_UVC;
> +
>  	memset(fmt, 0, sizeof(*fmt));
>  
> -	fmt->dataformat = fmeta == dev->info->meta_format
> -			? fmeta : V4L2_META_FMT_UVC;
> +	fmt->dataformat = fmeta;
>  	fmt->buffersize = UVC_METADATA_BUF_SIZE;
>  
>  	return 0;
> @@ -112,17 +118,21 @@ static int uvc_meta_v4l2_enum_formats(struct file *file, void *fh,
>  	struct v4l2_fh *vfh = file->private_data;
>  	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
>  	struct uvc_device *dev = stream->dev;
> -	u32 index = fdesc->index;
> +	u32 i;
> +
> +	if (fdesc->type != vfh->vdev->queue->type)
> +		return -EINVAL;
>  
> -	if (fdesc->type != vfh->vdev->queue->type ||
> -	    index > 1U || (index && !dev->info->meta_format))
> +	for (i = 0; (i < fdesc->index) && dev->meta_formats[i]; i++)
> +		;
> +	if (!dev->meta_formats[i])
>  		return -EINVAL;
>  
>  	memset(fdesc, 0, sizeof(*fdesc));
>  
>  	fdesc->type = vfh->vdev->queue->type;
> -	fdesc->index = index;
> -	fdesc->pixelformat = index ? dev->info->meta_format : V4L2_META_FMT_UVC;
> +	fdesc->index = i;
> +	fdesc->pixelformat = dev->meta_formats[i];
>  
>  	return 0;
>  }
> @@ -174,3 +184,17 @@ int uvc_meta_register(struct uvc_streaming *stream)
>  					 V4L2_BUF_TYPE_META_CAPTURE,
>  					 &uvc_meta_fops, &uvc_meta_ioctl_ops);
>  }
> +
> +void uvc_meta_init(struct uvc_device *dev)
> +{
> +	unsigned int i = 0;
> +
> +	dev->meta_formats[i++] = V4L2_META_FMT_UVC;
> +
> +	if (dev->info->meta_format &&
> +	    !WARN_ON(dev->info->meta_format == V4L2_META_FMT_UVC))
> +		dev->meta_formats[i++] = dev->info->meta_format;
> +
> +	 /* IMPORTANT: for new meta-formats update UVC_MAX_META_DATA_FORMATS. */
> +	dev->meta_formats[i++] = 0;
> +}
> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
> index 11d6e3c2ebdfbabd7bbe5722f88ff85f406d9bb6..b3c094c6591e7a71fc00e1096bcf493a83f330ad 100644
> --- a/drivers/media/usb/uvc/uvcvideo.h
> +++ b/drivers/media/usb/uvc/uvcvideo.h
> @@ -572,6 +572,8 @@ struct uvc_status {
>  	};
>  } __packed;
>  
> +#define UVC_MAX_META_DATA_FORMATS 3
> +
>  struct uvc_device {
>  	struct usb_device *udev;
>  	struct usb_interface *intf;
> @@ -582,6 +584,9 @@ struct uvc_device {
>  
>  	const struct uvc_device_info *info;
>  
> +	/* Zero-ended list of meta formats */
> +	u32 meta_formats[UVC_MAX_META_DATA_FORMATS + 1];
> +
>  	atomic_t nmappings;
>  
>  	/* Video control interface */
> @@ -751,6 +756,7 @@ int uvc_query_ctrl(struct uvc_device *dev, u8 query, u8 unit,
>  void uvc_video_clock_update(struct uvc_streaming *stream,
>  			    struct vb2_v4l2_buffer *vbuf,
>  			    struct uvc_buffer *buf);
> +void uvc_meta_init(struct uvc_device *dev);
>  int uvc_meta_register(struct uvc_streaming *stream);
>  
>  int uvc_register_video_device(struct uvc_device *dev,
>