> On Fri, 28 Jun 2024, Ben Kao <ben.kao@xxxxxxxxx> wrote: > > We found that the external monitor would be failed to display when > > hot-plug with dual Type-C USB cable on Dell WD19DC dock. > > Due to the host would receive 2 lanes setting when the first HPD, then > > receive 4 lanes setting later, but the host only sets 2 lanes DP and > > skips to set 4 lanes DP. I modify DP lane count if the current DP lane > > count is not the same as DPCD reading. > > > > Signed-off-by: Ben Kao <ben.kao@xxxxxxxxx> > > Please file a bug according to [1]. > > BR, > Jani. > > [1] https://drm.pages.freedesktop.org/intel-docs/how-to-file-i915-bugs.html This patch is for the bug number 11195 https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/11195 > > > > --- > > drivers/gpu/drm/i915/display/intel_dp.c | 6 ++++++ > > 1 file changed, 6 insertions(+) > > > > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c > > b/drivers/gpu/drm/i915/display/intel_dp.c > > index 5b3b6ae1e3d7..a9b9023c6744 100644 > > --- a/drivers/gpu/drm/i915/display/intel_dp.c > > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > > @@ -5545,6 +5545,12 @@ intel_dp_detect_dpcd(struct intel_dp *intel_dp) > > if (!intel_dp_get_dpcd(intel_dp)) > > return connector_status_disconnected; > > > > + /* lanes count changed */ > > + if (intel_dp->lane_count != drm_dp_max_lane_count(intel_dp->dpcd)) { > > + intel_dp->lane_count = drm_dp_max_lane_count(intel_dp- > >dpcd); > > + return connector_status_disconnected; > > + } > > + > > intel_dp->mst_detect = intel_dp_mst_detect(intel_dp); > > > > /* if there's no downstream port, we're done */ > > -- > Jani Nikula, Intel
