On Fri, Oct 27, 2017 at 12:48:39AM +0000, Pandiyan, Dhinakaran wrote: > > On Thu, 2017-10-26 at 22:41 +0300, Ville Syrjala wrote: > > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > > > DP dongles may signal downstream HPD via short HPD pulses. Setting the > > sink to DPMS off apparently kills the downstream HPD (at least on my > > DP->VGA dongle), so skip the DPMS off for such dongles when we turn > > off the port. > > > > Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx> > > Cc: Imre Deak <imre.deak@xxxxxxxxx> > > Cc: Pablo <pablodebiase@xxxxxxxxxxxxx> > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103472 > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99114 > > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > --- > > drivers/gpu/drm/i915/intel_dp.c | 18 +++++++++++++++++- > > 1 file changed, 17 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c > > index aa75f55eeb61..6ecc1b532f15 100644 > > --- a/drivers/gpu/drm/i915/intel_dp.c > > +++ b/drivers/gpu/drm/i915/intel_dp.c > > @@ -2673,6 +2673,21 @@ static void intel_dp_get_config(struct intel_encoder *encoder, > > } > > } > > > > +static bool downstream_hpd_needs_d0(struct intel_dp *intel_dp) > > +{ > > + /* > > + * DPCD 1.2 should support BRANCH_DEVICE_CTRL, and thus > > + * be capable of signalling downstream hpd with a long pulse. > > + * Whether or not that means D3 is safe to use is not clear, > > + * but let's assume so until proven otherwise. > > + * > > + * FIXME should really check all downstream ports... > > + */ > > + return intel_dp->dpcd[DP_DPCD_REV] == 0x11 && > > + intel_dp->dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT && > > + intel_dp->downstream_ports[0] & DP_DS_PORT_HPD; > > +} > > + > > static void intel_disable_dp(struct intel_encoder *encoder, > > const struct intel_crtc_state *old_crtc_state, > > const struct drm_connector_state *old_conn_state) > > @@ -2686,7 +2701,8 @@ static void intel_disable_dp(struct intel_encoder *encoder, > > It's not clear why the DDI counterpart is missing. Because I forgot we have the same code in two places ;) v2 coming up... > > > * ensure that we have vdd while we switch off the panel. */ > > intel_edp_panel_vdd_on(intel_dp); > > intel_edp_backlight_off(old_conn_state); > > - intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF); > > + if (!downstream_hpd_needs_d0(intel_dp)) > > + intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF); > > intel_edp_panel_off(intel_dp); > > } > > -- Ville Syrjälä Intel OTC _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
