From 39ff747b2f8197de51dae540e742de4acdbd7763 Mon Sep 17 00:00:00 2001 From: Shubhangi Shrivastava Date: Wed, 30 Mar 2016 18:05:26 +0530 Subject: [PATCH] drm/i915: force full detect on sink count change This patch checks for changes in sink count between short pulse hpds and forces full detect when there is a change. This will allow both detection of hotplug and unplug of panels through dongles that give only short pulse for such events. v2: changed variable type from u8 to bool (Jani) return immediately if perform_full_detect is set(Siva) v3: changed method of determining full detection from using pointer to return code (Siva) v4: changed comments to indicate meaning of return value of intel_dp_short_pulse and explain the use of return value from intel_dp_get_dpcd in intel_dp_short_pulse (Ander) Tested-by: Nathan D Ciobanu Signed-off-by: Sivakumar Thulasimani Signed-off-by: Shubhangi Shrivastava Reviewed-by: Ander Conselvan de Oliveira Signed-off-by: Ander Conselvan de Oliveira Link: http://patchwork.freedesktop.org/patch/msgid/1459341326-13142-5-git-send-email-shubhangi.shrivastava@intel.com --- drivers/gpu/drm/i915/intel_dp.c | 33 +++++++++++++++++++++++++++------ 1 file changed, 27 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index c8d22be1ff0f..da0c3d29fda8 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -4273,12 +4273,19 @@ intel_dp_check_link_status(struct intel_dp *intel_dp) * 2. Configure link according to Receiver Capabilities * 3. Use Link Training from 2.5.3.3 and 3.5.1.3 * 4. Check link status on receipt of hot-plug interrupt + * + * intel_dp_short_pulse - handles short pulse interrupts + * when full detection is not required. + * Returns %true if short pulse is handled and full detection + * is NOT required and %false otherwise. */ -static void +static bool intel_dp_short_pulse(struct intel_dp *intel_dp) { struct drm_device *dev = intel_dp_to_dev(intel_dp); u8 sink_irq_vector; + u8 old_sink_count = intel_dp->sink_count; + bool ret; /* * Clearing compliance test variables to allow capturing @@ -4288,9 +4295,17 @@ intel_dp_short_pulse(struct intel_dp *intel_dp) intel_dp->compliance_test_type = 0; intel_dp->compliance_test_data = 0; - /* Now read the DPCD to see if it's actually running */ - if (!intel_dp_get_dpcd(intel_dp)) { - return; + /* + * Now read the DPCD to see if it's actually running + * If the current value of sink count doesn't match with + * the value that was stored earlier or dpcd read failed + * we need to do full detection + */ + ret = intel_dp_get_dpcd(intel_dp); + + if ((old_sink_count != intel_dp->sink_count) || !ret) { + /* No need to proceed if we are going to do full detect */ + return false; } /* Try to read the source of the interrupt */ @@ -4310,6 +4325,8 @@ intel_dp_short_pulse(struct intel_dp *intel_dp) drm_modeset_lock(&dev->mode_config.connection_mutex, NULL); intel_dp_check_link_status(intel_dp); drm_modeset_unlock(&dev->mode_config.connection_mutex); + + return true; } /* XXX this is probably wrong for multiple downstream ports */ @@ -5043,8 +5060,12 @@ intel_dp_hpd_pulse(struct intel_digital_port *intel_dig_port, bool long_hpd) } } - if (!intel_dp->is_mst) - intel_dp_short_pulse(intel_dp); + if (!intel_dp->is_mst) { + if (!intel_dp_short_pulse(intel_dp)) { + intel_dp_long_pulse(intel_dp->attached_connector); + goto put_power; + } + } } ret = IRQ_HANDLED; -- 2.20.1