Some USB type-C dongles requires some time to power on before being
able to process aux channel transactions.
It was not a problem for older gens because there was a bridge
between DP port and USB-C controller adding some delay but ICL
handles type-C native.

So here trying to do a aux channel transaction at each 150ms for up 5
times, before giving up.

Cc: Paulo Zanoni <paulo.r.zan...@intel.com>
Signed-off-by: José Roberto de Souza <jose.so...@intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h      |  1 +
 drivers/gpu/drm/i915/intel_dp.c      | 14 +++++
 drivers/gpu/drm/i915/intel_drv.h     |  6 ++-
 drivers/gpu/drm/i915/intel_hotplug.c | 76 ++++++++++++++++++++++++++++
 4 files changed, 96 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 98547c242121..85950fb1fab1 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2792,6 +2792,7 @@ enum hpd_pin intel_hpd_pin_default(struct 
drm_i915_private *dev_priv,
 bool intel_hpd_disable(struct drm_i915_private *dev_priv, enum hpd_pin pin);
 void intel_hpd_enable(struct drm_i915_private *dev_priv, enum hpd_pin pin);
 void intel_hpd_suspend(struct drm_i915_private *dev_priv);
+void intel_hotplug_tc_wa_work(struct work_struct *__work);
 
 /* i915_irq.c */
 static inline void i915_queue_hangcheck(struct drm_i915_private *dev_priv)
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 27c6163426d6..e9060e325109 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -5307,6 +5307,7 @@ void intel_dp_encoder_destroy(struct drm_encoder *encoder)
 {
        struct intel_digital_port *intel_dig_port = enc_to_dig_port(encoder);
        struct intel_dp *intel_dp = &intel_dig_port->dp;
+       struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
 
        intel_dp_mst_encoder_cleanup(intel_dig_port);
        if (intel_dp_is_edp(intel_dp)) {
@@ -5323,6 +5324,15 @@ void intel_dp_encoder_destroy(struct drm_encoder 
*encoder)
                        unregister_reboot_notifier(&intel_dp->edp_notifier);
                        intel_dp->edp_notifier.notifier_call = NULL;
                }
+       } else {
+               /*
+                * ICL TC legacy HDMI ports is destroyed by this callback so
+                * it is necessary check if is DP before cancel delayed works
+                * as it is not initialized for legacy HDMI ports.
+                */
+               if (IS_ICELAKE(dev_priv) &&
+                   intel_dig_port->base.type == INTEL_OUTPUT_DP)
+                       cancel_delayed_work_sync(&intel_dp->tc_wa_work);
        }
 
        intel_dp_aux_fini(intel_dp);
@@ -6686,6 +6696,10 @@ intel_dp_init_connector(struct intel_digital_port 
*intel_dig_port,
                I915_WRITE(PEG_BAND_GAP_DATA, (temp & ~0xf) | 0xd);
        }
 
+       if (IS_ICELAKE(dev_priv) && !intel_dp_is_edp(intel_dp))
+               INIT_DELAYED_WORK(&intel_dp->tc_wa_work,
+                                 intel_hotplug_tc_wa_work);
+
        return true;
 
 fail:
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index bc30f107b430..61cfa4984c11 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1138,7 +1138,11 @@ struct intel_dp {
        int panel_power_cycle_delay;
        int backlight_on_delay;
        int backlight_off_delay;
-       struct delayed_work panel_vdd_work;
+       union {
+               struct delayed_work panel_vdd_work;
+               struct delayed_work tc_wa_work;
+       };
+       u8 tc_wa_count;
        bool want_panel_vdd;
        unsigned long last_power_on;
        unsigned long last_backlight_off;
diff --git a/drivers/gpu/drm/i915/intel_hotplug.c 
b/drivers/gpu/drm/i915/intel_hotplug.c
index 86b7457c6c8d..cfd469bce52c 100644
--- a/drivers/gpu/drm/i915/intel_hotplug.c
+++ b/drivers/gpu/drm/i915/intel_hotplug.c
@@ -342,6 +342,64 @@ static void i915_digport_work_func(struct work_struct 
*work)
        }
 }
 
+#define TC_WA_DELAY_MSEC 150
+#define TC_WA_TRIES 5
+
+/*
+ * Test if TC dongle is responsive return true if so otherwise schedule a
+ * work to try again and return false
+ */
+static bool intel_hotplug_tc_wa_test(struct intel_dp *intel_dp)
+{
+       u8 buff;
+
+       intel_dp->tc_wa_count++;
+
+       if (drm_dp_dpcd_read(&intel_dp->aux, DP_DPCD_REV, &buff, 1) != 1)
+               goto not_responsive;
+
+       if (!drm_probe_ddc(&intel_dp->aux.ddc))
+               goto not_responsive;
+
+       return true;
+
+not_responsive:
+       if (intel_dp->tc_wa_count < TC_WA_TRIES) {
+               unsigned long delay;
+
+               delay = msecs_to_jiffies(TC_WA_DELAY_MSEC);
+               schedule_delayed_work(&intel_dp->tc_wa_work, delay);
+       } else {
+               DRM_DEBUG_KMS("TC not responsive, giving up\n");
+       }
+
+       return false;
+}
+
+void intel_hotplug_tc_wa_work(struct work_struct *__work)
+{
+       struct intel_dp *intel_dp = container_of(to_delayed_work(__work),
+                                                struct intel_dp, tc_wa_work);
+       struct intel_connector *intel_connector = intel_dp->attached_connector;
+       struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+       struct intel_encoder *intel_encoder = &intel_dig_port->base;
+       struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
+       struct drm_device *dev = &dev_priv->drm;
+       bool ret;
+
+       if (!intel_digital_port_connected(intel_encoder))
+               return;
+
+       mutex_lock(&dev->mode_config.mutex);
+       ret = intel_hotplug_tc_wa_test(intel_dp);
+       if (ret)
+               ret = intel_encoder->hotplug(intel_encoder, intel_connector);
+       mutex_unlock(&dev->mode_config.mutex);
+
+       if (ret)
+               drm_kms_helper_hotplug_event(dev);
+}
+
 /*
  * Handle hotplug events outside the interrupt handler proper.
  */
@@ -377,9 +435,27 @@ static void i915_hotplug_work_func(struct work_struct 
*work)
                        continue;
                intel_encoder = intel_connector->encoder;
                if (hpd_event_bits & (1 << intel_encoder->hpd_pin)) {
+                       struct intel_digital_port *dig_port = 
enc_to_dig_port(&intel_encoder->base);
+
                        DRM_DEBUG_KMS("Connector %s (pin %i) received hotplug 
event.\n",
                                      connector->name, intel_encoder->hpd_pin);
 
+                       /*
+                        * TC WA: TC dongles can takes some time to be
+                        * responsible, so let's try to do a DPCD read to check
+                        * if it is ready, otherwise try again in a few msecs.
+                        */
+                       if (IS_ICELAKE(dev_priv) &&
+                           intel_digital_port_connected(intel_encoder) &&
+                           dig_port->tc_type != TC_PORT_LEGACY) {
+                               struct intel_dp *intel_dp;
+
+                               intel_dp = 
enc_to_intel_dp(&intel_encoder->base);
+                               intel_dp->tc_wa_count = 0;
+                               if (!intel_hotplug_tc_wa_test(intel_dp))
+                                       continue;
+                       }
+
                        changed |= intel_encoder->hotplug(intel_encoder,
                                                          intel_connector);
                }
-- 
2.19.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Reply via email to