drm/i915/hdcp: debug logs for sink related failures

Adding few more debug logs to identify the sink specific HDCP failures
along with a out of mem failure.

v2:
  Capturing the Bug and a-b

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=110991Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
cc: Daniel Vetter <daniel@ffwll.ch>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190708113319.2517-1-ramalingam.c@intel.com

drivers/gpu/drm/i915/display/intel_hdcp.c

@@ -523,12 +523,16 @@ int intel_hdcp_auth_downstream(struct intel_connector *connector)
 	 * authentication.
 	 */
 	num_downstream = DRM_HDCP_NUM_DOWNSTREAM(bstatus[0]);
-	if (num_downstream == 0)
+	if (num_downstream == 0) {
+		DRM_DEBUG_KMS("Repeater with zero downstream devices\n");
 		return -EINVAL;
+	}
 
 	ksv_fifo = kcalloc(DRM_HDCP_KSV_LEN, num_downstream, GFP_KERNEL);
-	if (!ksv_fifo)
+	if (!ksv_fifo) {
+		DRM_DEBUG_KMS("Out of mem: ksv_fifo\n");
 		return -ENOMEM;
+	}
 
 	ret = shim->read_ksv_fifo(intel_dig_port, num_downstream, ksv_fifo);
 	if (ret)
@@ -1206,8 +1210,10 @@ static int hdcp2_authentication_key_exchange(struct intel_connector *connector)
 	if (ret < 0)
 		return ret;
 
-	if (msgs.send_cert.rx_caps[0] != HDCP_2_2_RX_CAPS_VERSION_VAL)
+	if (msgs.send_cert.rx_caps[0] != HDCP_2_2_RX_CAPS_VERSION_VAL) {
+		DRM_DEBUG_KMS("cert.rx_caps dont claim HDCP2.2\n");
 		return -EINVAL;
+	}
 
 	hdcp->is_repeater = HDCP_2_2_RX_REPEATER(msgs.send_cert.rx_caps[2]);