[PATCH v6 25/35] misc/mei/hdcp: Initiate Wired HDCP2.2 Tx Session

[Ramalingam C]

Request ME FW to start the HDCP2.2 session for an intel port.
Prepares payloads for command WIRED_INITIATE_HDCP2_SESSION and sends
to ME FW.

On Success, ME FW will start a HDCP2.2 session for the port and
provides the content for HDCP2.2 AKE_Init message.

v2:
  Rebased.
v3:
  cldev is add as a separate parameter [Tomas]
  Redundant comment and typecast are removed [Tomas]
v4:
  %zd is used for size [Alexander]
  %s/return -1/return -EIO [Alexander]
  Spellings in commit msg is fixed [Uma]
v5:
  Rebased.
v6:
  No change.

Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
---
 drivers/misc/mei/hdcp/mei_hdcp.c | 70 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 69 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c
index adfb14a2ea4f..44b1aac03ff0 100644
--- a/drivers/misc/mei/hdcp/mei_hdcp.c
+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
@@ -32,14 +32,82 @@
 #include <linux/uuid.h>
 #include <linux/mei_cl_bus.h>
 #include <linux/component.h>
+#include <linux/mei_hdcp.h>
 #include <drm/i915_component.h>
+#include <drm/drm_connector.h>
+
+#include "mei_hdcp.h"
 
 bool mei_hdcp_component_registered;
 static struct mei_cl_device *mei_cldev;
 
+/*
+ * mei_initiate_hdcp2_session:
+ *	Function to start a Wired HDCP2.2 Tx Session with ME FW
+ *
+ * cldev		: Pointer for mei client device
+ * data			: Intel HW specific Data
+ * ake_data		: ptr to store AKE_Init
+ *
+ * Returns 0 on Success, <0 on Failure.
+ */
+static int mei_initiate_hdcp2_session(struct mei_cl_device *cldev,
+				      struct mei_hdcp_data *data,
+				      struct hdcp2_ake_init *ake_data)
+{
+	struct wired_cmd_initiate_hdcp2_session_in session_init_in = { { 0 } };
+	struct wired_cmd_initiate_hdcp2_session_out
+						session_init_out = { { 0 } };
+	struct device *dev;
+	ssize_t byte;
+
+	if (!data || !ake_data)
+		return -EINVAL;
+
+	dev = &cldev->dev;
+
+	session_init_in.header.api_version = HDCP_API_VERSION;
+	session_init_in.header.command_id = WIRED_INITIATE_HDCP2_SESSION;
+	session_init_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	session_init_in.header.buffer_len =
+				WIRED_CMD_BUF_LEN_INITIATE_HDCP2_SESSION_IN;
+
+	session_init_in.port.integrated_port_type = data->port_type;
+	session_init_in.port.physical_port = data->port;
+	session_init_in.protocol = (uint8_t)data->protocol;
+
+	byte = mei_cldev_send(cldev, (u8 *)&session_init_in,
+			      sizeof(session_init_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&session_init_out,
+			      sizeof(session_init_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (session_init_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X Failed. Status: 0x%X\n",
+			WIRED_INITIATE_HDCP2_SESSION,
+			session_init_out.header.status);
+		return -EIO;
+	}
+
+	ake_data->msg_id = HDCP_2_2_AKE_INIT;
+	ake_data->tx_caps = session_init_out.tx_caps;
+	memcpy(ake_data->r_tx, session_init_out.r_tx,
+	       sizeof(session_init_out.r_tx));
+
+	return 0;
+}
+
 struct i915_hdcp_component_ops mei_hdcp_component_ops = {
 	.owner					= THIS_MODULE,
-	.initiate_hdcp2_session			= NULL,
+	.initiate_hdcp2_session			= mei_initiate_hdcp2_session,
 	.verify_receiver_cert_prepare_km	= NULL,
 	.verify_hprime				= NULL,
 	.store_pairing_info			= NULL,
-- 
2.7.4