[PATCH v2 10/42] misc/mei/hdcp: Initiate Wired HDCP2.2 Tx Session

[Ramalingam C]

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

Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
---
 drivers/misc/mei/hdcp/mei_hdcp.c | 73 ++++++++++++++++++++++++++++++++++++++++
 include/linux/mei_hdcp.h         | 11 ++++++
 2 files changed, 84 insertions(+)

diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c
index 63f77800a6f7..516ad6a40616 100644
--- a/drivers/misc/mei/hdcp/mei_hdcp.c
+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
@@ -29,6 +29,7 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/uuid.h>
+#include <drm/drm_connector.h>
 
 #include "mei_hdcp.h"
 
@@ -46,6 +47,78 @@ static inline bool mei_cldev_active_and_enabled(struct mei_cl_device *cldev)
 	return mei_cldev_enabled(cldev);
 }
 
+/**
+ * mei_initiate_hdcp2_session:
+ *	Function to start a Wired HDCP2.2 Tx Session with ME FW
+ *
+ * @data		: Intel HW specific Data
+ * @ake_data		: ptr to store AKE_Init
+ *
+ * Returns 0 on Success, <0 on Failure.
+ */
+int mei_initiate_hdcp2_session(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 } };
+	enum me_hdcp_status status;
+	struct device *dev;
+	ssize_t byte;
+
+	if (!data || !ake_data)
+		return -EINVAL;
+
+	/* check for the mei_device enabled or not */
+	if (!mei_cldev_active_and_enabled(data->cldev))
+		return -ENODEV;
+
+	dev = &data->cldev->dev;
+
+	/* Fill header details */
+	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;
+
+	/* Fill in the In Data */
+	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;
+
+	/* Request to ME */
+	byte = mei_cldev_send(data->cldev, (u8 *)&session_init_in,
+			      sizeof(session_init_in));
+	if (byte < 0) {
+		dev_err(dev, "mei_cldev_send failed. %d\n", (int)byte);
+		return byte;
+	}
+
+	/* Response from ME */
+	byte = mei_cldev_recv(data->cldev, (u8 *)&session_init_out,
+			      sizeof(session_init_out));
+	if (byte < 0) {
+		dev_err(dev, "mei_cldev_recv failed. %d\n", (int)byte);
+		return byte;
+	}
+
+	status = (enum me_hdcp_status)session_init_out.header.status;
+	if (status != ME_HDCP_STATUS_SUCCESS) {
+		dev_err(dev, "ME cmd 0x%08X Failed. Status: 0x%X\n",
+			WIRED_INITIATE_HDCP2_SESSION, status);
+		return -1;
+	}
+
+	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;
+}
+EXPORT_SYMBOL(mei_initiate_hdcp2_session);
+
 static int mei_hdcp_probe(struct mei_cl_device *cldev,
 			  const struct mei_cl_device_id *id)
 {
diff --git a/include/linux/mei_hdcp.h b/include/linux/mei_hdcp.h
index 9a869d1cbd5d..c333528b9c1e 100644
--- a/include/linux/mei_hdcp.h
+++ b/include/linux/mei_hdcp.h
@@ -24,6 +24,7 @@
 #define _LINUX_MEI_HDCP_H
 
 #include <linux/mei_cl_bus.h>
+#include <drm/drm_hdcp.h>
 
 /*
  * Enumeration of the physical DDI available on the platform
@@ -101,6 +102,9 @@ int mei_hdcp_cldev_get_reference(void *client_data,
 						       struct mei_cl_device
 						       *cldev));
 void mei_hdcp_cldev_put_reference(struct mei_cl_device *cldev);
+
+int mei_initiate_hdcp2_session(struct mei_hdcp_data *data,
+			       struct hdcp2_ake_init *ake_data);
 #else
 static inline
 int mei_hdcp_cldev_get_reference(void *client_data,
@@ -114,5 +118,12 @@ int mei_hdcp_cldev_get_reference(void *client_data,
 static inline
 void mei_hdcp_cldev_put_reference(struct mei_cl_device *cldev)
 {}
+
+static inline
+int mei_initiate_hdcp2_session(struct mei_hdcp_data *data,
+			       struct hdcp2_ake_init *ake_data)
+{
+	return -ENODEV;
+}
 #endif /* defined (CONFIG_INTEL_MEI_HDCP) */
 #endif /* defined (_LINUX_MEI_HDCP_H) */
-- 
2.7.4