Re: [PATCH 3/4] drm/uapi: document the USB subconnector type

From: Laurent Pinchart
Date: Wed Aug 02 2023 - 15:13:53 EST


On Wed, Aug 02, 2023 at 10:01:19PM +0300, Dmitry Baryshkov wrote:
> On 02/08/2023 21:55, Laurent Pinchart wrote:
> > Hi Dmitry,
> >
> > Thank you for the patch.
> >
> > On Sat, Jul 29, 2023 at 03:49:12AM +0300, Dmitry Baryshkov wrote:
> >> To properly define the USB-C DP altmode connectors, add the USB
> >> subconnector type.
> >>
> >> Suggested-by: Simon Ser <contact@xxxxxxxxxxx>
> >> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> >> ---
> >> drivers/gpu/drm/drm_connector.c | 1 +
> >> include/uapi/drm/drm_mode.h | 1 +
> >> 2 files changed, 2 insertions(+)
> >>
> >> diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> >> index a6066e4a5e9a..9e96b038f5d0 100644
> >> --- a/drivers/gpu/drm/drm_connector.c
> >> +++ b/drivers/gpu/drm/drm_connector.c
> >> @@ -1050,6 +1050,7 @@ static const struct drm_prop_enum_list drm_dp_subconnector_enum_list[] = {
> >> { DRM_MODE_SUBCONNECTOR_DisplayPort, "DP" }, /* DP */
> >> { DRM_MODE_SUBCONNECTOR_Wireless, "Wireless" }, /* DP */
> >> { DRM_MODE_SUBCONNECTOR_Native, "Native" }, /* DP */
> >> + { DRM_MODE_SUBCONNECTOR_USB, "USB" }, /* DP */
> >
> > Should this be DRM_MODE_SUBCONNECTOR_USB_C and "USB-C", in case we get
> > another USB type later ?
>
> Hmm, which id should I use for micro-USB then? (consider anx7808,
> SlimPort). I thought about using DRM_MODE_SUBCONNECTOR_USB for both of
> them. But maybe I should add another subtype for SlimPort.

I suppose it depends on whether userspace needs a way to differentiate
those. Do you have a good visibility on the userspace use cases ?

> >> };
> >>
> >> DRM_ENUM_NAME_FN(drm_get_dp_subconnector_name,
> >> diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
> >> index 92d96a2b6763..0f74918b011c 100644
> >> --- a/include/uapi/drm/drm_mode.h
> >> +++ b/include/uapi/drm/drm_mode.h
> >> @@ -398,6 +398,7 @@ enum drm_mode_subconnector {
> >> DRM_MODE_SUBCONNECTOR_HDMIA = 11, /* DP */
> >> DRM_MODE_SUBCONNECTOR_Native = 15, /* DP */
> >> DRM_MODE_SUBCONNECTOR_Wireless = 18, /* DP */
> >> + DRM_MODE_SUBCONNECTOR_USB = 20, /* DP */
> >> };
> >>
> >> #define DRM_MODE_CONNECTOR_Unknown 0

--
Regards,

Laurent Pinchart