Hi Laurent
On Sun, 29 Jun 2025 at 20:13, Laurent Pinchart
<laurent.pinchart@xxxxxxxxxxxxxxxx> wrote:
>
> Hi Ricardo,
>
> Thank you for the patch.
>
> On Thu, Jun 05, 2025 at 05:53:03PM +0000, Ricardo Ribalda wrote:
> > Virtual entities need to provide more values than get_cur and get_cur
>
> I think you meant "get_info and get_cur".
>
> > for their controls. Add support for get_def, get_min, get_max and
> > get_res.
>
> Do they ? The UVC specification defines controls that don't list
> GET_DEF, GET_MIN, GET_MAX and GET_RES as mandatory requests. Can't we do
> the same for the software controls ? This patch is meant to support the
> UVC_SWENTITY_ORIENTATION and UVC_SWENTITY_ROTATION control in the next
> patch, and those are read-only controls. Aren't GET_INFO and GET_CUR
> enough ?
V4L2_CID_CAMERA_ROTATION has the type UVC_CTRL_DATA_TYPE_UNSIGNED,
that time requires get_min and get_max.
We can create a new type UVC_CTRL_DATA_TYPE_UNSIGNED_READ_ONLY that
fakes min, max and res, but I think that it is cleaner this approach.
>
> >
> > This is a preparation patch.
> >
> > Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
> > ---
> > drivers/media/usb/uvc/uvc_ctrl.c | 12 ++++++++++++
> > drivers/media/usb/uvc/uvcvideo.h | 8 ++++++++
> > 2 files changed, 20 insertions(+)
> >
> > diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> > index 21ec7b978bc7aca21db7cb8fd5d135d876f3330c..59be62ae24a4219fa9d7aacf2ae7382c95362178 100644
> > --- a/drivers/media/usb/uvc/uvc_ctrl.c
> > +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> > @@ -596,6 +596,18 @@ static int uvc_ctrl_query_entity(struct uvc_device *dev,
> > if (query == UVC_GET_CUR && ctrl->entity->get_cur)
> > return ctrl->entity->get_cur(dev, ctrl->entity,
> > ctrl->info.selector, data, len);
> > + if (query == UVC_GET_DEF && ctrl->entity->get_def)
> > + return ctrl->entity->get_def(dev, ctrl->entity,
> > + ctrl->info.selector, data, len);
> > + if (query == UVC_GET_MIN && ctrl->entity->get_min)
> > + return ctrl->entity->get_min(dev, ctrl->entity,
> > + ctrl->info.selector, data, len);
> > + if (query == UVC_GET_MAX && ctrl->entity->get_max)
> > + return ctrl->entity->get_max(dev, ctrl->entity,
> > + ctrl->info.selector, data, len);
> > + if (query == UVC_GET_RES && ctrl->entity->get_res)
> > + return ctrl->entity->get_res(dev, ctrl->entity,
> > + ctrl->info.selector, data, len);
> > if (query == UVC_GET_INFO && ctrl->entity->get_info)
> > return ctrl->entity->get_info(dev, ctrl->entity,
> > ctrl->info.selector, data);
> > diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
> > index a931750bdea25b9062dcc7644bf5f2ed89c1cb4c..d6da8ed3ad4cf3377df49923e051fe04d83d2e38 100644
> > --- a/drivers/media/usb/uvc/uvcvideo.h
> > +++ b/drivers/media/usb/uvc/uvcvideo.h
> > @@ -261,6 +261,14 @@ struct uvc_entity {
> > u8 cs, u8 *caps);
> > int (*get_cur)(struct uvc_device *dev, struct uvc_entity *entity,
> > u8 cs, void *data, u16 size);
> > + int (*get_def)(struct uvc_device *dev, struct uvc_entity *entity,
> > + u8 cs, void *data, u16 size);
> > + int (*get_min)(struct uvc_device *dev, struct uvc_entity *entity,
> > + u8 cs, void *data, u16 size);
> > + int (*get_max)(struct uvc_device *dev, struct uvc_entity *entity,
> > + u8 cs, void *data, u16 size);
> > + int (*get_res)(struct uvc_device *dev, struct uvc_entity *entity,
> > + u8 cs, void *data, u16 size);
> >
> > unsigned int ncontrols;
> > struct uvc_control *controls;
>
> --
> Regards,
>
> Laurent Pinchart
--
Ricardo Ribalda
