[PATCH v8 20/35] 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.
v7:
  Collected the rb-ed by.
  Realigning the patches in the series.
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 | 85 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 85 insertions(+)

diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c
index d4067d17f382..ca8f82d25343 100644
--- a/drivers/misc/mei/hdcp/mei_hdcp.c
+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
@@ -12,6 +12,91 @@
 #include <linux/slab.h>
 #include <linux/uuid.h>
 #include <linux/mei_cl_bus.h>
+#include <linux/mei_hdcp.h>
+#include <drm/drm_connector.h>
+#include <drm/i915_component.h>
+
+#include "mei_hdcp.h"
+
+/*
+ * mei_initiate_hdcp2_session:
+ * Function to start a Wired HDCP2.2 Tx Session with ME FW
+ *
+ * @dev : device corresponding to the mei_cl_device
+ * @hdcp_data : Intel HW specific hdcp data
+ * @ake_data : AKE_Init msg from mei.
+ *
+ * Returns 0 on Success, <0 on Failure.
+ */
+static int mei_initiate_hdcp2_session(struct device *dev, void *hdcp_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 mei_cl_device *cldev;
+	struct mei_hdcp_data *data = hdcp_data;
+	ssize_t byte;
+
+	if (!dev || !data || !ake_data)
+		return -EINVAL;
+
+	cldev = to_mei_cl_device(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;
+}
+
+static __attribute__((unused))
+struct i915_hdcp_component_ops mei_hdcp_ops = {
+	.owner = THIS_MODULE,
+	.initiate_hdcp2_session = mei_initiate_hdcp2_session,
+	.verify_receiver_cert_prepare_km = NULL,
+	.verify_hprime = NULL,
+	.store_pairing_info = NULL,
+	.initiate_locality_check = NULL,
+	.verify_lprime = NULL,
+	.get_session_key = NULL,
+	.repeater_check_flow_prepare_ack = NULL,
+	.verify_mprime = NULL,
+	.enable_hdcp_authentication = NULL,
+	.close_hdcp_session = NULL,
+};
 
 static int mei_hdcp_probe(struct mei_cl_device *cldev,
 			  const struct mei_cl_device_id *id)
-- 
2.7.4