[v4,13/41] misc/mei/hdcp: Verify L_prime

Commit Message

Ramalingam C May 21, 2018, 12:53 p.m. UTC

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]

Signed-off-by: Ramalingam C <[e-mail]>
---
 drivers/misc/mei/hdcp/mei_hdcp.c | 60 ++++++++++++++++++++++++++++++++++++++++
 include/linux/mei_hdcp.h         |  8 ++++++
 2 files changed, 68 insertions(+)

Patch

diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c
index 324e50736518..9582109923e4 100644
--- a/drivers/misc/mei/hdcp/mei_hdcp.c
+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
@@ -365,6 +365,66 @@  int mei_initiate_locality_check(struct mei_cl_device *cldev,
 }
 EXPORT_SYMBOL(mei_initiate_locality_check);
 
+/*
+ * 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
+ */
+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;
+}
+EXPORT_SYMBOL(mei_verify_lprime);
+
 static void
 mei_cldev_state_notify_clients(struct mei_cl_device *cldev, bool enabled)
 {
diff --git a/include/linux/mei_hdcp.h b/include/linux/mei_hdcp.h
index 54453c34d54e..c9a0bb9d10e8 100644
--- a/include/linux/mei_hdcp.h
+++ b/include/linux/mei_hdcp.h
@@ -125,6 +125,8 @@  int mei_store_pairing_info(struct mei_cl_device *cldev,
 int mei_initiate_locality_check(struct mei_cl_device *cldev,
 				struct mei_hdcp_data *data,
 				struct hdcp2_lc_init *lc_init_data);
+int mei_verify_lprime(struct mei_cl_device *cldev, struct mei_hdcp_data *data,
+		      struct hdcp2_lc_send_lprime *rx_lprime);
 #else
 static inline int mei_cldev_register_notify(struct notifier_block *nb)
 {
@@ -175,5 +177,11 @@  int mei_initiate_locality_check(struct mei_cl_device *cldev,
 {
 	return -ENODEV;
 }
+static inline
+int mei_verify_lprime(struct mei_cl_device *cldev, struct mei_hdcp_data *data,
+		      struct hdcp2_lc_send_lprime *rx_lprime)
+{
+	return -ENODEV;
+}
 #endif /* IS_ENABLED(CONFIG_INTEL_MEI_HDCP) */
 #endif /* defined (_LINUX_MEI_HDCP_H) */