Currently a DDI port may register the DP hotplug handler even though it's used with HDMI, and the DP HPD handler overrides the encoder type forcibly to DP. This caused the inconsistency on a machine connected with a HDMI monitor; upon a hotplug event, the DDI port is suddenly switched to be handled as a DP although the same monitor is kept connected, and this leads to the erroneous blank output. This patch papers over the bug by excluding the previous HDMI encoder type from this override. This should be fixed more fundamentally, e.g. by moving the encoder type reset from the HPD or by having individual encoder objects for HDMI and DP. But since the bug has been present for a long time (3.17), it's better to have a quick-n-dirty fix for now, and keep working on a cleaner fix. Bugzilla: http://bugzilla.opensuse.org/show_bug.cgi?id=955190 Fixes: 0e32b39ceed6 ('drm/i915: add DP 1.2 MST support (v0.7)') Cc: <stable@xxxxxxxxxxxxxxx> # v3.17+ Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> --- drivers/gpu/drm/i915/intel_dp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 09bdd94ca3ba..d34e64300d66 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -5153,7 +5153,8 @@ intel_dp_hpd_pulse(struct intel_digital_port *intel_dig_port, bool long_hpd) enum intel_display_power_domain power_domain; enum irqreturn ret = IRQ_NONE; - if (intel_dig_port->base.type != INTEL_OUTPUT_EDP) + if (intel_dig_port->base.type != INTEL_OUTPUT_EDP && + intel_dig_port->base.type != INTEL_OUTPUT_HDMI) intel_dig_port->base.type = INTEL_OUTPUT_DISPLAYPORT; if (long_hpd && intel_dig_port->base.type == INTEL_OUTPUT_EDP) { -- 2.6.3 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx