[Intel-gfx] [PATCH v2 2/3] drm/i915/hdcp: link hdcp2 recovery on link enc stopped

[Anshuman Gupta]

When stream encryption enabling fails due to Link encryption status
has stopped, prepare HDCP2 for recovery by disabling port authentication
and encryption such that it can re-attempt port authentication
and encryption.

Cc: Ramalingam C <ramalingam.c at intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
---
 drivers/gpu/drm/i915/display/intel_hdcp.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
index 08dd6b46749d..9a70c164c377 100644
--- a/drivers/gpu/drm/i915/display/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
@@ -1706,6 +1706,7 @@ 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;
@@ -1715,7 +1716,8 @@ 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) {
@@ -1729,6 +1731,15 @@ static int hdcp2_enable_stream_encryption(struct intel_connector *connector)
 			    transcoder_name(hdcp->stream_transcoder));
 	}
 
+	return 0;
+
+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;
 }
 
-- 
2.26.2