[Intel-gfx] [PATCH v8 24/35] misc/mei/hdcp: Initiate Locality check

[Ramalingam C]

Requests ME to start the second stage of HDCP2.2 authentication,
called Locality Check.

On Success, ME FW will provide LC_Init message to send to hdcp sink.

v2:
  Rebased.
v3:
  cldev is passed as first parameter [Tomas]
  Redundant comments and cast are removed [Tomas]
v4:
  %zd used for ssize_t [Alexander]
  %s/return -1/return -EIO [Alexander]
  Style fixed [Uma]
v5:
  Rebased.
v6:
  No change.
v7:
  Collected the Rb-ed by.
  Rebasing.
v8:
  Adjust to the new mei interface.
  Fix for Kdoc.

Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
Reviewed-by: Uma Shankar <uma.shankar at intel.com>
---
 drivers/misc/mei/hdcp/mei_hdcp.c | 57 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 56 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c
index 27c94d883386..6db98a51fce1 100644
--- a/drivers/misc/mei/hdcp/mei_hdcp.c
+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
@@ -283,6 +283,61 @@ mei_store_pairing_info(struct device *dev, void *hdcp_data,
 	return 0;
 }
 
+/*
+ * mei_initiate_locality_check : Function to prepare LC_Init.
+ *
+ * @dev : device corresponding to the mei_cl_device
+ * @hdcp_data : Intel HW specific hdcp data
+ * @hdcp2_lc_init : LC_Init msg output
+ *
+ * Returns 0 on Success, <0 on Failure
+ */
+static int mei_initiate_locality_check(struct device *dev, void *hdcp_data,
+				       struct hdcp2_lc_init *lc_init_data)
+{
+	struct wired_cmd_init_locality_check_in lc_init_in = { { 0 } };
+	struct wired_cmd_init_locality_check_out lc_init_out = { { 0 } };
+	struct mei_cl_device *cldev;
+	struct mei_hdcp_data *data = hdcp_data;
+	ssize_t byte;
+
+	if (!dev || !data || !lc_init_data)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(dev);
+
+	lc_init_in.header.api_version = HDCP_API_VERSION;
+	lc_init_in.header.command_id = WIRED_INIT_LOCALITY_CHECK;
+	lc_init_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	lc_init_in.header.buffer_len = WIRED_CMD_BUF_LEN_INIT_LOCALITY_CHECK_IN;
+
+	lc_init_in.port.integrated_port_type = data->port_type;
+	lc_init_in.port.physical_port = data->port;
+
+	byte = mei_cldev_send(cldev, (u8 *)&lc_init_in, sizeof(lc_init_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&lc_init_out, sizeof(lc_init_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (lc_init_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X Failed. status: 0x%X\n",
+			WIRED_INIT_LOCALITY_CHECK, lc_init_out.header.status);
+		return -EIO;
+	}
+
+	lc_init_data->msg_id = HDCP_2_2_LC_INIT;
+	memcpy(lc_init_data->r_n, lc_init_out.r_n, HDCP_2_2_RN_LEN);
+
+	return 0;
+}
+
 static __attribute__((unused))
 struct i915_hdcp_component_ops mei_hdcp_ops = {
 	.owner = THIS_MODULE,
@@ -290,7 +345,7 @@ struct i915_hdcp_component_ops mei_hdcp_ops = {
 	.verify_receiver_cert_prepare_km = mei_verify_receiver_cert_prepare_km,
 	.verify_hprime = mei_verify_hprime,
 	.store_pairing_info = mei_store_pairing_info,
-	.initiate_locality_check = NULL,
+	.initiate_locality_check = mei_initiate_locality_check,
 	.verify_lprime = NULL,
 	.get_session_key = NULL,
 	.repeater_check_flow_prepare_ack = NULL,
-- 
2.7.4