[PATCH v4 6/8] drm/i915/lobf: Check for sink error and disable LOBF

[Animesh Manna <animesh.manna@xxxxxxxxx>]

Disable LOBF/ALPM for any erroneous condition from sink side.

v1: Initial version.
v2: Add centralized alpm error handling. [Jouni]

Signed-off-by: Animesh Manna <animesh.manna@xxxxxxxxx>
---
 drivers/gpu/drm/i915/display/intel_alpm.c | 25 +++++++++++++++++++++++
 drivers/gpu/drm/i915/display/intel_alpm.h |  1 +
 drivers/gpu/drm/i915/display/intel_dp.c   |  3 +++
 drivers/gpu/drm/i915/display/intel_psr.c  | 15 ++------------
 4 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c b/drivers/gpu/drm/i915/display/intel_alpm.c
index 5c70677ac3c0..92ec03956755 100644
--- a/drivers/gpu/drm/i915/display/intel_alpm.c
+++ b/drivers/gpu/drm/i915/display/intel_alpm.c
@@ -532,3 +532,28 @@ void intel_alpm_disable(struct intel_dp *intel_dp)
 		     PORT_ALPM_CTL(cpu_transcoder),
 		     PORT_ALPM_CTL_ALPM_AUX_LESS_ENABLE, 0);
 }
+
+bool intel_alpm_get_error(struct intel_dp *intel_dp)
+{
+	struct intel_display *display = to_intel_display(intel_dp);
+	struct drm_dp_aux *aux = &intel_dp->aux;
+	u8 val;
+	int r;
+
+	r = drm_dp_dpcd_readb(aux, DP_RECEIVER_ALPM_STATUS, &val);
+	if (r != 1) {
+		drm_err(display->drm, "Error reading ALPM status\n");
+		return true;
+	}
+
+	if (val & DP_ALPM_LOCK_TIMEOUT_ERROR) {
+		drm_dbg_kms(display->drm,
+			    "ALPM lock timeout error, disabling ALPM\n");
+
+		/* Clearing error */
+		drm_dp_dpcd_writeb(aux, DP_RECEIVER_ALPM_STATUS, val);
+		return true;
+	}
+
+	return false;
+}
diff --git a/drivers/gpu/drm/i915/display/intel_alpm.h b/drivers/gpu/drm/i915/display/intel_alpm.h
index c6efd25c2062..22469fd4cba5 100644
--- a/drivers/gpu/drm/i915/display/intel_alpm.h
+++ b/drivers/gpu/drm/i915/display/intel_alpm.h
@@ -30,4 +30,5 @@ void intel_alpm_lobf_debugfs_add(struct intel_connector *connector);
 bool intel_alpm_aux_wake_supported(struct intel_dp *intel_dp);
 bool intel_alpm_aux_less_wake_supported(struct intel_dp *intel_dp);
 void intel_alpm_disable(struct intel_dp *intel_dp);
+bool intel_alpm_get_error(struct intel_dp *intel_dp);
 #endif
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 03ca2e02ab02..24ad7680cdf2 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -5360,6 +5360,9 @@ intel_dp_short_pulse(struct intel_dp *intel_dp)
 
 	intel_psr_short_pulse(intel_dp);
 
+	if (intel_alpm_get_error(intel_dp))
+		intel_alpm_disable(intel_dp);
+
 	if (intel_dp_test_short_pulse(intel_dp))
 		reprobe_needed = true;
 
diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index 1d202f2eb356..fde9463d5ec9 100644
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -3406,28 +3406,17 @@ static int psr_get_status_and_error_status(struct intel_dp *intel_dp,
 static void psr_alpm_check(struct intel_dp *intel_dp)
 {
 	struct intel_display *display = to_intel_display(intel_dp);
-	struct drm_dp_aux *aux = &intel_dp->aux;
 	struct intel_psr *psr = &intel_dp->psr;
-	u8 val;
-	int r;
 
 	if (!psr->sel_update_enabled)
 		return;
 
-	r = drm_dp_dpcd_readb(aux, DP_RECEIVER_ALPM_STATUS, &val);
-	if (r != 1) {
-		drm_err(display->drm, "Error reading ALPM status\n");
-		return;
-	}
-
-	if (val & DP_ALPM_LOCK_TIMEOUT_ERROR) {
+	if (intel_alpm_get_error(intel_dp)) {
 		intel_psr_disable_locked(intel_dp);
 		psr->sink_not_reliable = true;
+		intel_alpm_disable(intel_dp);
 		drm_dbg_kms(display->drm,
 			    "ALPM lock timeout error, disabling PSR\n");
-
-		/* Clearing error */
-		drm_dp_dpcd_writeb(aux, DP_RECEIVER_ALPM_STATUS, val);
 	}
 }
 
-- 
2.29.0