[Intel-gfx] [PATCH v7 30/39] misc/mei/hdcp: Verify L_prime

[Ramalingam C]

Request to ME to verify the LPrime received from HDCP sink.

On Success, ME FW will verify the received Lprime by calculating and
comparing with L.

This represents the completion of Locality Check.

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 fixed [Uma]
v5:
  Rebased.
v6:
  No change.
v7:
  Collected the Rb-ed by.
  Rebasing.

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 | 62 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 61 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c
index ab1aed39d5a4..3ae50240c656 100644
--- a/drivers/misc/mei/hdcp/mei_hdcp.c
+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
@@ -340,6 +340,66 @@ static int mei_initiate_locality_check(struct mei_cl_device *cldev,
 	return 0;
 }
 
+/*
+ * mei_verify_lprime:
+ *	Function to verify lprime.
+ *
+ * cldev		: Pointer for mei client device
+ * data			: Intel HW specific Data
+ * rx_lprime		: Pointer for LC_Send_L_prime
+ *
+ * Returns 0 on Success, <0 on Failure
+ */
+static int mei_verify_lprime(struct mei_cl_device *cldev,
+			     struct mei_hdcp_data *data,
+			     struct hdcp2_lc_send_lprime *rx_lprime)
+{
+	struct wired_cmd_validate_locality_in verify_lprime_in = { { 0 } };
+	struct wired_cmd_validate_locality_out verify_lprime_out = { { 0 } };
+	struct device *dev;
+	ssize_t byte;
+
+	if (!data || !rx_lprime)
+		return -EINVAL;
+
+	dev = &cldev->dev;
+
+	verify_lprime_in.header.api_version = HDCP_API_VERSION;
+	verify_lprime_in.header.command_id = WIRED_VALIDATE_LOCALITY;
+	verify_lprime_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	verify_lprime_in.header.buffer_len =
+					WIRED_CMD_BUF_LEN_VALIDATE_LOCALITY_IN;
+
+	verify_lprime_in.port.integrated_port_type = data->port_type;
+	verify_lprime_in.port.physical_port = data->port;
+
+	memcpy(verify_lprime_in.l_prime, rx_lprime->l_prime,
+	       sizeof(rx_lprime->l_prime));
+
+	byte = mei_cldev_send(cldev, (u8 *)&verify_lprime_in,
+			      sizeof(verify_lprime_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&verify_lprime_out,
+			      sizeof(verify_lprime_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (verify_lprime_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
+			WIRED_VALIDATE_LOCALITY,
+			verify_lprime_out.header.status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
 static __attribute__((unused))
 struct i915_hdcp_component_ops mei_hdcp_ops = {
 	.owner					= THIS_MODULE,
@@ -349,7 +409,7 @@ struct i915_hdcp_component_ops mei_hdcp_ops = {
 	.verify_hprime				= mei_verify_hprime,
 	.store_pairing_info			= mei_store_pairing_info,
 	.initiate_locality_check		= mei_initiate_locality_check,
-	.verify_lprime				= NULL,
+	.verify_lprime				= mei_verify_lprime,
 	.get_session_key			= NULL,
 	.repeater_check_flow_prepare_ack	= NULL,
 	.verify_mprime				= NULL,
-- 
2.7.4