This is already uAPI, xserver parses it. It's useful to document since user-space might want to lookup the parent connector. Additionally, people (me included) have misunderstood the PATH property for being stable across reboots, but since a KMS object ID is baked in there that's not the case. So PATH shouldn't be used as-is in config files and such. Signed-off-by: Simon Ser <contact@xxxxxxxxxxx> Cc: Pekka Paalanen <pekka.paalanen@xxxxxxxxxxxxx> Cc: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> --- drivers/gpu/drm/drm_connector.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c index c3725086f413..392bec1355a3 100644 --- a/drivers/gpu/drm/drm_connector.c +++ b/drivers/gpu/drm/drm_connector.c @@ -1198,6 +1198,11 @@ static const u32 dp_colorspaces = * drm_connector_set_path_property(), in the case of DP MST with the * path property the MST manager created. Userspace cannot change this * property. + * + * In the case of DP MST, the property has the format + * ``mst:<parent>-<ports>`` where ``<parent>`` is the KMS object ID of the + * parent connector and ``<ports>`` is a hyphen-separated list of DP MST + * port numbers. Note, KMS object IDs are not stable across reboots. * TILE: * Connector tile group property to indicate how a set of DRM connector * compose together into one logical screen. This is used by both high-res -- 2.42.0
