[PATCH v2 11/21] drm/i915/dp: Use check link state work in the hotplug handler

[Imre Deak]

Simplify things by retraining a DP link if a bad link is detected in the
hotplug handler from the encoder's check link state work, similarly to
how this is done after a modeset link training failure.

Signed-off-by: Imre Deak <imre.deak at intel.com>
---
 drivers/gpu/drm/i915/display/g4x_dp.c    | 20 +-------------------
 drivers/gpu/drm/i915/display/intel_ddi.c | 11 +++++------
 drivers/gpu/drm/i915/display/intel_dp.c  |  8 ++++++++
 drivers/gpu/drm/i915/display/intel_dp.h  |  1 +
 4 files changed, 15 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/g4x_dp.c b/drivers/gpu/drm/i915/display/g4x_dp.c
index 0d7424a7581e6..1f3b6b3956a1c 100644
--- a/drivers/gpu/drm/i915/display/g4x_dp.c
+++ b/drivers/gpu/drm/i915/display/g4x_dp.c
@@ -1160,9 +1160,7 @@ intel_dp_hotplug(struct intel_encoder *encoder,
 		 struct intel_connector *connector)
 {
 	struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
-	struct drm_modeset_acquire_ctx ctx;
 	enum intel_hotplug_state state;
-	int ret;
 
 	if (intel_dp->compliance.test_active &&
 	    intel_dp->compliance.test_type == DP_TEST_LINK_PHY_TEST_PATTERN) {
@@ -1173,23 +1171,7 @@ intel_dp_hotplug(struct intel_encoder *encoder,
 
 	state = intel_encoder_hotplug(encoder, connector);
 
-	drm_modeset_acquire_init(&ctx, 0);
-
-	for (;;) {
-		ret = intel_dp_retrain_link(encoder, &ctx);
-
-		if (ret == -EDEADLK) {
-			drm_modeset_backoff(&ctx);
-			continue;
-		}
-
-		break;
-	}
-
-	drm_modeset_drop_locks(&ctx);
-	drm_modeset_acquire_fini(&ctx);
-	drm_WARN(encoder->base.dev, ret,
-		 "Acquiring modeset locks failed with %i\n", ret);
+	intel_dp_check_link_state(intel_dp);
 
 	/*
 	 * Keeping it consistent with intel_ddi_hotplug() and
diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
index 58e57a7704811..ea24404724075 100644
--- a/drivers/gpu/drm/i915/display/intel_ddi.c
+++ b/drivers/gpu/drm/i915/display/intel_ddi.c
@@ -4566,14 +4566,13 @@ intel_ddi_hotplug(struct intel_encoder *encoder,
 	state = intel_encoder_hotplug(encoder, connector);
 
 	if (!intel_tc_port_link_reset(dig_port)) {
-		intel_modeset_lock_ctx_retry(&ctx, NULL, 0, ret) {
-			if (connector->base.connector_type == DRM_MODE_CONNECTOR_HDMIA)
+		if (connector->base.connector_type == DRM_MODE_CONNECTOR_HDMIA) {
+			intel_modeset_lock_ctx_retry(&ctx, NULL, 0, ret)
 				ret = intel_hdmi_reset_link(encoder, &ctx);
-			else
-				ret = intel_dp_retrain_link(encoder, &ctx);
+			drm_WARN_ON(encoder->base.dev, ret);
+		} else {
+			intel_dp_check_link_state(intel_dp);
 		}
-
-		drm_WARN_ON(encoder->base.dev, ret);
 	}
 
 	/*
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 87f9f12814b93..ff4ed6bb520d8 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -5064,6 +5064,14 @@ intel_dp_needs_link_retrain(struct intel_dp *intel_dp)
 	return !intel_dp_link_ok(intel_dp, link_status);
 }
 
+void intel_dp_check_link_state(struct intel_dp *intel_dp)
+{
+	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
+
+	if (intel_dp_needs_link_retrain(intel_dp))
+		intel_ddi_queue_link_check(dig_port, 0);
+}
+
 static bool intel_dp_has_connector(struct intel_dp *intel_dp,
 				   const struct drm_connector_state *conn_state)
 {
diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h
index 24777c035e2ad..3fa53ac601d58 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.h
+++ b/drivers/gpu/drm/i915/display/intel_dp.h
@@ -57,6 +57,7 @@ void intel_dp_set_link_params(struct intel_dp *intel_dp,
 int intel_dp_get_active_pipes(struct intel_dp *intel_dp,
 			      struct drm_modeset_acquire_ctx *ctx,
 			      u8 *pipe_mask);
+void intel_dp_check_link_state(struct intel_dp *intel_dp);
 int intel_dp_retrain_link(struct intel_encoder *encoder,
 			  struct drm_modeset_acquire_ctx *ctx);
 void intel_dp_set_power(struct intel_dp *intel_dp, u8 mode);
-- 
2.43.3