From 2e4b90fbe75536c978218bb3eb1d04f8988e13cd Mon Sep 17 00:00:00 2001 From: Imre Deak Date: Thu, 4 Jan 2024 10:30:07 +0200 Subject: drm/i915: Filter out glitches on HPD lines during hotplug detection MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Glitches deasserting the connector HPD line can lead to incorrectly detecting a disconnect event (a glitch asserting the line will only cause a redundant connect->disconnect transition). The source of such a glitch can be noise on the line or a 0.5ms-1ms MST IRQ_HPD pulse. TypeC ports in the DP-alt or TBT-alt mode filter out these glitches inernally, but for others the driver has to do this. Make it so by polling the HPD line on these connectors for 4 ms. Link: https://patchwork.freedesktop.org/patch/msgid/20240104083008.2715733-12-imre.deak@intel.com Reviewed-by: Jouni Högander Signed-off-by: Imre Deak --- drivers/gpu/drm/i915/display/intel_tc.h | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/gpu/drm/i915/display/intel_tc.h') diff --git a/drivers/gpu/drm/i915/display/intel_tc.h b/drivers/gpu/drm/i915/display/intel_tc.h index 936fa2daaa74..26c4265368c1 100644 --- a/drivers/gpu/drm/i915/display/intel_tc.h +++ b/drivers/gpu/drm/i915/display/intel_tc.h @@ -15,6 +15,7 @@ struct intel_encoder; bool intel_tc_port_in_tbt_alt_mode(struct intel_digital_port *dig_port); bool intel_tc_port_in_dp_alt_mode(struct intel_digital_port *dig_port); bool intel_tc_port_in_legacy_mode(struct intel_digital_port *dig_port); +bool intel_tc_port_handles_hpd_glitches(struct intel_digital_port *dig_port); bool intel_tc_port_connected(struct intel_encoder *encoder); -- cgit v1.2.3