Re: [PATCH v4] media: uvcvideo: Fix bandwidth error for Alcor camera

[Jackie Liu <liu.yun@xxxxxxxxx>]

Hi, Chao.

在 2022/11/22 16:48, Ai Chao 写道:
> For Alcor Corp. Slave camera(1b17:6684/2017:0011), it support to output
>   compressed video data, and it return a wrong dwMaxPayloadTransferSize
Instead of starting with a space, please start with a letter.
>   fields. This is a fireware issue, but the manufacturer cannot provide
>   a const return fieldsby the fireware. For some device, it requested

s/fireware/firmware/ ???

>   2752512 B/frame bandwidth. For normally device, it requested 3072 or 1024
>   B/frame bandwidth. so we check the dwMaxPayloadTransferSize fields,if it
>   large than 0x1000, reset dwMaxPayloadTransferSize to 1024, and the camera
>   preview normally.

Until here.

> Signed-off-by: Ai Chao <aichao@xxxxxxxxxx>
>
> ---
> change for v4
> - Change usb_match_one_id to usb_match_id
> - Modify the discription
>
> change for v3
> - Add VID/PID 2017:0011
>
> change for v2
> - Used usb_match_one_id to check VID and PID
> ---
> ---
>   drivers/media/usb/uvc/uvc_video.c | 12 ++++++++++++
>   1 file changed, 12 insertions(+)
>
> diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c
> index d2eb9066e4dc..75bdd71d0e5a 100644
> --- a/drivers/media/usb/uvc/uvc_video.c
> +++ b/drivers/media/usb/uvc/uvc_video.c
> @@ -135,6 +135,11 @@ static void uvc_fixup_video_ctrl(struct uvc_streaming *stream,
>   	static const struct usb_device_id elgato_cam_link_4k = {
>   		USB_DEVICE(0x0fd9, 0x0066)
>   	};
> +	static const struct usb_device_id alcor_corp_slave_cam[] = {
> +		{ USB_DEVICE(0x2017, 0x0011) },
> +		{ USB_DEVICE(0x1b17, 0x6684) },
> +		{ }
> +	};
>   	struct uvc_format *format = NULL;
>   	struct uvc_frame *frame = NULL;
>   	unsigned int i;
> @@ -234,6 +239,13 @@ static void uvc_fixup_video_ctrl(struct uvc_streaming *stream,
>   
>   		ctrl->dwMaxPayloadTransferSize = bandwidth;
>   	}
> +
> +	/* Alcor Corp. Slave camera return wrong dwMaxPayloadTransferSize */
> +	if ((format->flags & UVC_FMT_FLAG_COMPRESSED) &&
> +	    (ctrl->dwMaxPayloadTransferSize > 0x1000) &&
> +	    usb_match_id(stream->dev->intf, alcor_corp_slave_cam)) {
> +		ctrl->dwMaxPayloadTransferSize = 1024;
> +	}
>   }
>   
>   static size_t uvc_video_ctrl_size(struct uvc_streaming *stream)

Others, LGTM.

Reviewed-by: Jackie Liu <liuyun01@xxxxxxxxxx>

--
Jackie Liu