[Intel-gfx] [PATCH 2/3] drm/i915/hdcp: recover link on stream enc enable/disable failure

[Anshuman Gupta]

When stream encryption {enable,disable} fails, prepare HDCP2 for
recovery by enabling port authentication and port encryption again.

Cc: Ramalingam C <ramalingam.c at intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
---
 drivers/gpu/drm/i915/display/intel_hdcp.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
index 24720da16b89..68ad7741cf60 100644
--- a/drivers/gpu/drm/i915/display/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
@@ -1717,6 +1717,7 @@ static int hdcp2_enable_stream_encryption(struct intel_connector *connector)
 {
 	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+	struct hdcp_port_data *data = &dig_port->hdcp_port_data;
 	struct intel_hdcp *hdcp = &connector->hdcp;
 	enum transcoder cpu_transcoder = hdcp->cpu_transcoder;
 	enum port port = dig_port->base.port;
@@ -1726,7 +1727,8 @@ static int hdcp2_enable_stream_encryption(struct intel_connector *connector)
 			    LINK_ENCRYPTION_STATUS)) {
 		drm_err(&dev_priv->drm, "[%s:%d] HDCP 2.2 Link is not encrypted\n",
 			connector->base.name, connector->base.base.id);
-		return -EPERM;
+		ret = -EPERM;
+		goto link_recover;
 	}
 
 	if (hdcp->shim->stream_2_2_encryption) {
@@ -1734,12 +1736,19 @@ static int hdcp2_enable_stream_encryption(struct intel_connector *connector)
 		if (ret) {
 			drm_err(&dev_priv->drm, "[%s:%d] Failed to enable HDCP 2.2 stream enc\n",
 				connector->base.name, connector->base.base.id);
-			return ret;
+			goto link_recover;
 		}
 		drm_dbg_kms(&dev_priv->drm, "HDCP 2.2 transcoder: %s stream encrypted\n",
 			    transcoder_name(hdcp->stream_transcoder));
 	}
 
+link_recover:
+	if (hdcp2_deauthenticate_port(connector) < 0)
+		drm_dbg_kms(&dev_priv->drm, "Port deauth failed.\n");
+
+	dig_port->hdcp_auth_status = false;
+	data->k = 0;
+
 	return ret;
 }
 
@@ -1955,7 +1964,7 @@ _intel_hdcp2_disable(struct intel_connector *connector, bool hdcp2_link_recovery
 		if (ret) {
 			drm_err(&i915->drm, "[%s:%d] Failed to disable HDCP 2.2 stream enc\n",
 				connector->base.name, connector->base.base.id);
-			return ret;
+			goto link_recover;
 		}
 		drm_dbg_kms(&i915->drm, "HDCP 2.2 transcoder: %s stream encryption disabled\n",
 			    transcoder_name(hdcp->stream_transcoder));
@@ -1966,6 +1975,8 @@ _intel_hdcp2_disable(struct intel_connector *connector, bool hdcp2_link_recovery
 
 	ret = hdcp2_disable_encryption(connector);
 
+link_recover:
+
 	if (hdcp2_deauthenticate_port(connector) < 0)
 		drm_dbg_kms(&i915->drm, "Port deauth failed.\n");
 
-- 
2.26.2