Hi Ricardo,
Thank you for the patch.
On Mon, Jun 10, 2024 at 11:09:54PM +0000, Ricardo Ribalda wrote:
> The UVC 1.5 standard defines 4 values for the PLF control: Off, 50Hz,
> 60Hz and Auto. But it does not clearly define if all the values must be
> implemented or not.
>
> Instead of just using the UVC version to determine what the PLF control
> can do, probe it.
>
> Reviewed-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
> Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> ---
> drivers/media/usb/uvc/uvc_ctrl.c | 52 ++++++++++++++++++++++++++++++++++++----
> 1 file changed, 47 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> index d82cfc56dfd5..5b77ac308c84 100644
> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> @@ -495,18 +495,60 @@ static const struct uvc_control_mapping uvc_ctrl_power_line_mapping_uvc15 = {
> V4L2_CID_POWER_LINE_FREQUENCY_DISABLED),
> };
>
> -static int __uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
> +static int __uvc_ctrl_add_mapping_to_list(struct uvc_video_chain *chain,
> struct uvc_control *ctrl, const struct uvc_control_mapping *mapping);
>
> static int uvc_ctrl_add_plf_mapping(struct uvc_video_chain *chain,
> struct uvc_control *ctrl, const struct uvc_control_mapping *mapping)
> {
> + const struct uvc_control_mapping *out_mapping =
> + &uvc_ctrl_power_line_mapping_uvc11;
> + u8 *buf __free(kfree) = NULL;
> + u8 init_val;
> + int ret;
> +
> + buf = kmalloc(sizeof(*buf), GFP_KERNEL);
> + if (!buf)
> + return -ENOMEM;
> +
> + /* Save the default PLF value, so we can restore it. */
> + ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR, ctrl->entity->id,
> + chain->dev->intfnum, ctrl->info.selector,
> + buf, sizeof(*buf));
> + /* If we cannot read the control skip it. */
> + if (ret)
> + return ret;
> + init_val = *buf;
> +
> + /* If PLF value cannot be set to off, it is limited. */
> + *buf = V4L2_CID_POWER_LINE_FREQUENCY_DISABLED;
> + ret = uvc_query_ctrl(chain->dev, UVC_SET_CUR, ctrl->entity->id,
> + chain->dev->intfnum, ctrl->info.selector,
> + buf, sizeof(*buf));
> + if (ret)
> + return __uvc_ctrl_add_mapping_to_list(chain, ctrl,
> + &uvc_ctrl_power_line_mapping_limited);
> +
> + /* UVC 1.1 does not define auto, we can exit. */
> if (chain->dev->uvc_version < 0x150)
> - return __uvc_ctrl_add_mapping(chain, ctrl,
> - &uvc_ctrl_power_line_mapping_uvc11);
> + goto end;
> +
> + /* Check if the device supports auto. */
> + *buf = V4L2_CID_POWER_LINE_FREQUENCY_AUTO;
> + ret = uvc_query_ctrl(chain->dev, UVC_SET_CUR, ctrl->entity->id,
> + chain->dev->intfnum, ctrl->info.selector,
> + buf, sizeof(*buf));
> + if (!ret)
> + out_mapping = &uvc_ctrl_power_line_mapping_uvc15;
> +
> +end:
> + /* Restore initial value and add mapping. */
> + *buf = init_val;
> + uvc_query_ctrl(chain->dev, UVC_SET_CUR, ctrl->entity->id,
> + chain->dev->intfnum, ctrl->info.selector,
> + buf, sizeof(*buf));
>
> - return __uvc_ctrl_add_mapping(chain, ctrl,
> - &uvc_ctrl_power_line_mapping_uvc15);
> + return __uvc_ctrl_add_mapping_to_list(chain, ctrl, out_mapping);
> }
>
> static const struct uvc_control_mapping uvc_ctrl_mappings[] = {
--
Regards,
Laurent Pinchart
