Hi Laurent and Hans On Sun, 29 Jun 2025 at 20:06, Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> wrote: > > Hi Ricardo, > > Thank you for the patch. > > I would use "software entities" and not "virtual entities" in the > subject line and everywhere else, as those entities are not virtual. > > On Thu, Jun 05, 2025 at 05:53:05PM +0000, Ricardo Ribalda wrote: > > Neither the GPIO nor the SWENTITY entities form part of the device > > pipeline. We just create them to hold emulated uvc controls. > > > > When the device initializes, a warning is thrown by the v4l2 core: > > uvcvideo 1-1:1.0: Entity type for entity SWENTITY was not initialized! > > > > There are no entity function that matches what we are doing here, and > > it does not make to much sense to create a function for entities that > > do not really exist. > > I don't agree with this. The purpose of reporting entities to userspace > through the MC API is to let application enumerate what entities a > device contains. Being able to enumerate software entities seems as > useful as being able to enumerate hardware entities. What function shall we use in this case? Nothing here seems to match a software entity https://www.kernel.org/doc/html/latest/userspace-api/media/mediactl/media-types.html Any suggestion for name? Shall we just live with the warning in dmesg? > > > Do not create MC entities for them and pretend nothing happened here. > > > > Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx> > > --- > > drivers/media/usb/uvc/uvc_entity.c | 10 ++++++++++ > > 1 file changed, 10 insertions(+) > > > > diff --git a/drivers/media/usb/uvc/uvc_entity.c b/drivers/media/usb/uvc/uvc_entity.c > > index d1a652ef35ec34801bd39a5124b834edf838a79e..2dbeb4ab0c4c8cc763ff2dcd2d836a50f3c6a040 100644 > > --- a/drivers/media/usb/uvc/uvc_entity.c > > +++ b/drivers/media/usb/uvc/uvc_entity.c > > @@ -72,6 +72,16 @@ static int uvc_mc_init_entity(struct uvc_video_chain *chain, > > { > > int ret; > > > > + /* > > + * Do not initialize virtual entities, they do not really exist > > + * and are not connected to any other entities. > > + */ > > + switch (UVC_ENTITY_TYPE(entity)) { > > + case UVC_EXT_GPIO_UNIT: > > + case UVC_SWENTITY_UNIT: > > + return 0; > > + } > > + > > if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING) { > > u32 function; > > > > -- > Regards, > > Laurent Pinchart -- Ricardo Ribalda
