misc/mei/hdcp: Enabling the HDCP authentication

Request to ME to configure a port as authenticated.

On Success, ME FW will mark the port as authenticated and provides
HDCP cipher with the encryption keys.

Enabling the Authentication can be requested once all stages of
HDCP2.2 authentication is completed by interacting with ME FW.

Only after this stage, driver can enable the HDCP encryption for
the port, through HW registers.

v2: Rebased.
v3:
  cldev is passed as first parameter [Tomas]
  Redundant comments and cast are removed [Tomas]
v4:
  %zd for ssize_t [Alexander]
  %s/return -1/return -EIO [Alexander]
  Style and typos fixed [Uma]
v5: Rebased.
v6:
  Collected the Rb-ed by.
  Rebased.
v7:
  Adjust to the new mei interface.
  Fix for Kdoc.
v8:
  K-Doc addition. [Tomas]
v9:
  renamed func as mei_hdcp_* [Tomas]
  Inline function is defined for DDI index [Tomas]
v10:
  K-Doc fix. [Tomas]
v11:
  Rebased.
Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Acked-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1550772730-23280-14-git-send-email-ramalingam.c@intel.com

drivers/misc/mei/hdcp/mei_hdcp.c

@@ -605,6 +605,59 @@ static int mei_hdcp_verify_mprime(struct device *dev,
 	return 0;
 }
 
+/**
+ * mei_hdcp_enable_authentication() - Mark a port as authenticated
+ * through ME FW
+ * @dev: device corresponding to the mei_cl_device
+ * @data: Intel HW specific hdcp data
+ *
+ * Return: 0 on Success, <0 on Failure
+ */
+static int mei_hdcp_enable_authentication(struct device *dev,
+					  struct hdcp_port_data *data)
+{
+	struct wired_cmd_enable_auth_in enable_auth_in = { { 0 } };
+	struct wired_cmd_enable_auth_out enable_auth_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	ssize_t byte;
+
+	if (!dev || !data)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	enable_auth_in.header.api_version = HDCP_API_VERSION;
+	enable_auth_in.header.command_id = WIRED_ENABLE_AUTH;
+	enable_auth_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	enable_auth_in.header.buffer_len = WIRED_CMD_BUF_LEN_ENABLE_AUTH_IN;
+
+	enable_auth_in.port.integrated_port_type = data->port_type;
+	enable_auth_in.port.physical_port = mei_get_ddi_index(data->port);
+	enable_auth_in.stream_type = data->streams[0].stream_type;
+
+	byte = mei_cldev_send(cldev, (u8 *)&enable_auth_in,
+			      sizeof(enable_auth_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&enable_auth_out,
+			      sizeof(enable_auth_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (enable_auth_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
+			WIRED_ENABLE_AUTH, enable_auth_out.header.status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
 static const __attribute__((unused))
 struct i915_hdcp_component_ops mei_hdcp_ops = {
 	.owner = THIS_MODULE,
@@ -619,7 +672,7 @@ struct i915_hdcp_component_ops mei_hdcp_ops = {
 	.repeater_check_flow_prepare_ack =
 				mei_hdcp_repeater_check_flow_prepare_ack,
 	.verify_mprime = mei_hdcp_verify_mprime,
-	.enable_hdcp_authentication = NULL,
+	.enable_hdcp_authentication = mei_hdcp_enable_authentication,
 	.close_hdcp_session = NULL,
 };