// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright © 2019 Intel Corporation
 *
 * mei_hdcp.c: HDCP client driver for mei bus
 *
 * Author:
 * Ramalingam C <ramalingam.c@intel.com>
 */

/**
 * DOC: MEI_HDCP Client Driver
 *
 * The mei_hdcp driver acts as a translation layer between HDCP 2.2
 * protocol  implementer (I915) and ME FW by translating HDCP2.2
 * negotiation messages to ME FW command payloads and vice versa.
 */

#include <linux/module.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/mei.h>
#include <linux/mei_cl_bus.h>
#include <linux/component.h>
#include <drm/drm_connector.h>
#include <drm/intel/i915_component.h>
#include <drm/intel/i915_hdcp_interface.h>

#include "mei_hdcp.h"

/**
 * mei_hdcp_initiate_session() - Initiate a Wired HDCP2.2 Tx Session in ME FW
 * @dev: device corresponding to the mei_cl_device
 * @data: Intel HW specific hdcp data
 * @ake_data: AKE_Init msg output.
 *
 * Return:  0 on Success, <0 on Failure.
 */
static int
mei_hdcp_initiate_session(struct device *dev, struct hdcp_port_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 mei_cl_device *cldev;
        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 = FW_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 = (u8)data->hdcp_ddi;
        session_init_in.port.attached_transcoder = (u8)data->hdcp_transcoder;
        session_init_in.protocol = 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 != FW_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, HDCP_2_2_RTX_LEN);

        return 0;
}

/**
 * mei_hdcp_verify_receiver_cert_prepare_km() - Verify the Receiver Certificate
 * AKE_Send_Cert and prepare AKE_Stored_Km/AKE_No_Stored_Km
 * @dev: device corresponding to the mei_cl_device
 * @data: Intel HW specific hdcp data
 * @rx_cert: AKE_Send_Cert for verification
 * @km_stored: Pairing status flag output
 * @ek_pub_km: AKE_Stored_Km/AKE_No_Stored_Km output msg
 * @msg_sz : size of AKE_XXXXX_Km output msg
 *
 * Return: 0 on Success, <0 on Failure
 */
static int
mei_hdcp_verify_receiver_cert_prepare_km(struct device *dev,
                                         struct hdcp_port_data *data,
                                         struct hdcp2_ake_send_cert *rx_cert,
                                         bool *km_stored,
                                         struct hdcp2_ake_no_stored_km
                                                                *ek_pub_km,
                                         size_t *msg_sz)
{
        struct wired_cmd_verify_receiver_cert_in verify_rxcert_in = { { 0 } };
        struct wired_cmd_verify_receiver_cert_out verify_rxcert_out = { { 0 } };
        struct mei_cl_device *cldev;
        ssize_t byte;

        if (!dev || !data || !rx_cert || !km_stored || !ek_pub_km || !msg_sz)
                return -EINVAL;

        cldev = to_mei_cl_device(dev);

        verify_rxcert_in.header.api_version = HDCP_API_VERSION;
        verify_rxcert_in.header.command_id = WIRED_VERIFY_RECEIVER_CERT;
        verify_rxcert_in.header.status = FW_HDCP_STATUS_SUCCESS;
        verify_rxcert_in.header.buffer_len =
                                WIRED_CMD_BUF_LEN_VERIFY_RECEIVER_CERT_IN;

        verify_rxcert_in.port.integrated_port_type = data->port_type;
        verify_rxcert_in.port.physical_port = (u8)data->hdcp_ddi;
        verify_rxcert_in.port.attached_transcoder = (u8)data->hdcp_transcoder;

        verify_rxcert_in.cert_rx = rx_cert->cert_rx;
        memcpy(verify_rxcert_in.r_rx, &rx_cert->r_rx, HDCP_2_2_RRX_LEN);
        memcpy(verify_rxcert_in.rx_caps, rx_cert->rx_caps, HDCP_2_2_RXCAPS_LEN);

        byte = mei_cldev_send(cldev, (u8 *)&verify_rxcert_in,
                              sizeof(verify_rxcert_in));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_send failed: %zd\n", byte);
                return byte;
        }

        byte = mei_cldev_recv(cldev, (u8 *)&verify_rxcert_out,
                              sizeof(verify_rxcert_out));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_recv failed: %zd\n", byte);
                return byte;
        }

        if (verify_rxcert_out.header.status != FW_HDCP_STATUS_SUCCESS) {
                dev_dbg(dev, "ME cmd 0x%08X Failed. Status: 0x%X\n",
                        WIRED_VERIFY_RECEIVER_CERT,
                        verify_rxcert_out.header.status);
                return -EIO;
        }

        *km_stored = !!verify_rxcert_out.km_stored;
        if (verify_rxcert_out.km_stored) {
                ek_pub_km->msg_id = HDCP_2_2_AKE_STORED_KM;
                *msg_sz = sizeof(struct hdcp2_ake_stored_km);
        } else {
                ek_pub_km->msg_id = HDCP_2_2_AKE_NO_STORED_KM;
                *msg_sz = sizeof(struct hdcp2_ake_no_stored_km);
        }

        memcpy(ek_pub_km->e_kpub_km, &verify_rxcert_out.ekm_buff,
               sizeof(verify_rxcert_out.ekm_buff));

        return 0;
}

/**
 * mei_hdcp_verify_hprime() - Verify AKE_Send_H_prime at ME FW.
 * @dev: device corresponding to the mei_cl_device
 * @data: Intel HW specific hdcp data
 * @rx_hprime: AKE_Send_H_prime msg for ME FW verification
 *
 * Return: 0 on Success, <0 on Failure
 */
static int
mei_hdcp_verify_hprime(struct device *dev, struct hdcp_port_data *data,
                       struct hdcp2_ake_send_hprime *rx_hprime)
{
        struct wired_cmd_ake_send_hprime_in send_hprime_in = { { 0 } };
        struct wired_cmd_ake_send_hprime_out send_hprime_out = { { 0 } };
        struct mei_cl_device *cldev;
        ssize_t byte;

        if (!dev || !data || !rx_hprime)
                return -EINVAL;

        cldev = to_mei_cl_device(dev);

        send_hprime_in.header.api_version = HDCP_API_VERSION;
        send_hprime_in.header.command_id = WIRED_AKE_SEND_HPRIME;
        send_hprime_in.header.status = FW_HDCP_STATUS_SUCCESS;
        send_hprime_in.header.buffer_len = WIRED_CMD_BUF_LEN_AKE_SEND_HPRIME_IN;

        send_hprime_in.port.integrated_port_type = data->port_type;
        send_hprime_in.port.physical_port = (u8)data->hdcp_ddi;
        send_hprime_in.port.attached_transcoder = (u8)data->hdcp_transcoder;

        memcpy(send_hprime_in.h_prime, rx_hprime->h_prime,
               HDCP_2_2_H_PRIME_LEN);

        byte = mei_cldev_send(cldev, (u8 *)&send_hprime_in,
                              sizeof(send_hprime_in));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
                return byte;
        }

        byte = mei_cldev_recv(cldev, (u8 *)&send_hprime_out,
                              sizeof(send_hprime_out));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
                return byte;
        }

        if (send_hprime_out.header.status != FW_HDCP_STATUS_SUCCESS) {
                dev_dbg(dev, "ME cmd 0x%08X Failed. Status: 0x%X\n",
                        WIRED_AKE_SEND_HPRIME, send_hprime_out.header.status);
                return -EIO;
        }

        return 0;
}

/**
 * mei_hdcp_store_pairing_info() - Store pairing info received at ME FW
 * @dev: device corresponding to the mei_cl_device
 * @data: Intel HW specific hdcp data
 * @pairing_info: AKE_Send_Pairing_Info msg input to ME FW
 *
 * Return: 0 on Success, <0 on Failure
 */
static int
mei_hdcp_store_pairing_info(struct device *dev, struct hdcp_port_data *data,
                            struct hdcp2_ake_send_pairing_info *pairing_info)
{
        struct wired_cmd_ake_send_pairing_info_in pairing_info_in = { { 0 } };
        struct wired_cmd_ake_send_pairing_info_out pairing_info_out = { { 0 } };
        struct mei_cl_device *cldev;
        ssize_t byte;

        if (!dev || !data || !pairing_info)
                return -EINVAL;

        cldev = to_mei_cl_device(dev);

        pairing_info_in.header.api_version = HDCP_API_VERSION;
        pairing_info_in.header.command_id = WIRED_AKE_SEND_PAIRING_INFO;
        pairing_info_in.header.status = FW_HDCP_STATUS_SUCCESS;
        pairing_info_in.header.buffer_len =
                                        WIRED_CMD_BUF_LEN_SEND_PAIRING_INFO_IN;

        pairing_info_in.port.integrated_port_type = data->port_type;
        pairing_info_in.port.physical_port = (u8)data->hdcp_ddi;
        pairing_info_in.port.attached_transcoder = (u8)data->hdcp_transcoder;

        memcpy(pairing_info_in.e_kh_km, pairing_info->e_kh_km,
               HDCP_2_2_E_KH_KM_LEN);

        byte = mei_cldev_send(cldev, (u8 *)&pairing_info_in,
                              sizeof(pairing_info_in));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
                return byte;
        }

        byte = mei_cldev_recv(cldev, (u8 *)&pairing_info_out,
                              sizeof(pairing_info_out));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
                return byte;
        }

        if (pairing_info_out.header.status != FW_HDCP_STATUS_SUCCESS) {
                dev_dbg(dev, "ME cmd 0x%08X failed. Status: 0x%X\n",
                        WIRED_AKE_SEND_PAIRING_INFO,
                        pairing_info_out.header.status);
                return -EIO;
        }

        return 0;
}

/**
 * mei_hdcp_initiate_locality_check() - Prepare LC_Init
 * @dev: device corresponding to the mei_cl_device
 * @data: Intel HW specific hdcp data
 * @lc_init_data: LC_Init msg output
 *
 * Return: 0 on Success, <0 on Failure
 */
static int
mei_hdcp_initiate_locality_check(struct device *dev,
                                 struct hdcp_port_data *data,
                                 struct hdcp2_lc_init *lc_init_data)
{
        struct wired_cmd_init_locality_check_in lc_init_in = { { 0 } };
        struct wired_cmd_init_locality_check_out lc_init_out = { { 0 } };
        struct mei_cl_device *cldev;
        ssize_t byte;

        if (!dev || !data || !lc_init_data)
                return -EINVAL;

        cldev = to_mei_cl_device(dev);

        lc_init_in.header.api_version = HDCP_API_VERSION;
        lc_init_in.header.command_id = WIRED_INIT_LOCALITY_CHECK;
        lc_init_in.header.status = FW_HDCP_STATUS_SUCCESS;
        lc_init_in.header.buffer_len = WIRED_CMD_BUF_LEN_INIT_LOCALITY_CHECK_IN;

        lc_init_in.port.integrated_port_type = data->port_type;
        lc_init_in.port.physical_port = (u8)data->hdcp_ddi;
        lc_init_in.port.attached_transcoder = (u8)data->hdcp_transcoder;

        byte = mei_cldev_send(cldev, (u8 *)&lc_init_in, sizeof(lc_init_in));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
                return byte;
        }

        byte = mei_cldev_recv(cldev, (u8 *)&lc_init_out, sizeof(lc_init_out));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
                return byte;
        }

        if (lc_init_out.header.status != FW_HDCP_STATUS_SUCCESS) {
                dev_dbg(dev, "ME cmd 0x%08X Failed. status: 0x%X\n",
                        WIRED_INIT_LOCALITY_CHECK, lc_init_out.header.status);
                return -EIO;
        }

        lc_init_data->msg_id = HDCP_2_2_LC_INIT;
        memcpy(lc_init_data->r_n, lc_init_out.r_n, HDCP_2_2_RN_LEN);

        return 0;
}

/**
 * mei_hdcp_verify_lprime() - Verify lprime.
 * @dev: device corresponding to the mei_cl_device
 * @data: Intel HW specific hdcp data
 * @rx_lprime: LC_Send_L_prime msg for ME FW verification
 *
 * Return: 0 on Success, <0 on Failure
 */
static int
mei_hdcp_verify_lprime(struct device *dev, struct hdcp_port_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 mei_cl_device *cldev;
        ssize_t byte;

        if (!dev || !data || !rx_lprime)
                return -EINVAL;

        cldev = to_mei_cl_device(dev);

        verify_lprime_in.header.api_version = HDCP_API_VERSION;
        verify_lprime_in.header.command_id = WIRED_VALIDATE_LOCALITY;
        verify_lprime_in.header.status = FW_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 = (u8)data->hdcp_ddi;
        verify_lprime_in.port.attached_transcoder = (u8)data->hdcp_transcoder;

        memcpy(verify_lprime_in.l_prime, rx_lprime->l_prime,
               HDCP_2_2_L_PRIME_LEN);

        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 != FW_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;
}

/**
 * mei_hdcp_get_session_key() - Prepare SKE_Send_Eks.
 * @dev: device corresponding to the mei_cl_device
 * @data: Intel HW specific hdcp data
 * @ske_data: SKE_Send_Eks msg output from ME FW.
 *
 * Return: 0 on Success, <0 on Failure
 */
static int mei_hdcp_get_session_key(struct device *dev,
                                    struct hdcp_port_data *data,
                                    struct hdcp2_ske_send_eks *ske_data)
{
        struct wired_cmd_get_session_key_in get_skey_in = { { 0 } };
        struct wired_cmd_get_session_key_out get_skey_out = { { 0 } };
        struct mei_cl_device *cldev;
        ssize_t byte;

        if (!dev || !data || !ske_data)
                return -EINVAL;

        cldev = to_mei_cl_device(dev);

        get_skey_in.header.api_version = HDCP_API_VERSION;
        get_skey_in.header.command_id = WIRED_GET_SESSION_KEY;
        get_skey_in.header.status = FW_HDCP_STATUS_SUCCESS;
        get_skey_in.header.buffer_len = WIRED_CMD_BUF_LEN_GET_SESSION_KEY_IN;

        get_skey_in.port.integrated_port_type = data->port_type;
        get_skey_in.port.physical_port = (u8)data->hdcp_ddi;
        get_skey_in.port.attached_transcoder = (u8)data->hdcp_transcoder;

        byte = mei_cldev_send(cldev, (u8 *)&get_skey_in, sizeof(get_skey_in));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
                return byte;
        }

        byte = mei_cldev_recv(cldev, (u8 *)&get_skey_out, sizeof(get_skey_out));

        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
                return byte;
        }

        if (get_skey_out.header.status != FW_HDCP_STATUS_SUCCESS) {
                dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
                        WIRED_GET_SESSION_KEY, get_skey_out.header.status);
                return -EIO;
        }

        ske_data->msg_id = HDCP_2_2_SKE_SEND_EKS;
        memcpy(ske_data->e_dkey_ks, get_skey_out.e_dkey_ks,
               HDCP_2_2_E_DKEY_KS_LEN);
        memcpy(ske_data->riv, get_skey_out.r_iv, HDCP_2_2_RIV_LEN);

        return 0;
}

/**
 * mei_hdcp_repeater_check_flow_prepare_ack() - Validate the Downstream topology
 * and prepare rep_ack.
 * @dev: device corresponding to the mei_cl_device
 * @data: Intel HW specific hdcp data
 * @rep_topology: Receiver ID List to be validated
 * @rep_send_ack : repeater ack from ME FW.
 *
 * Return: 0 on Success, <0 on Failure
 */
static int
mei_hdcp_repeater_check_flow_prepare_ack(struct device *dev,
                                         struct hdcp_port_data *data,
                                         struct hdcp2_rep_send_receiverid_list
                                                        *rep_topology,
                                         struct hdcp2_rep_send_ack
                                                        *rep_send_ack)
{
        struct wired_cmd_verify_repeater_in verify_repeater_in = { { 0 } };
        struct wired_cmd_verify_repeater_out verify_repeater_out = { { 0 } };
        struct mei_cl_device *cldev;
        ssize_t byte;

        if (!dev || !rep_topology || !rep_send_ack || !data)
                return -EINVAL;

        cldev = to_mei_cl_device(dev);

        verify_repeater_in.header.api_version = HDCP_API_VERSION;
        verify_repeater_in.header.command_id = WIRED_VERIFY_REPEATER;
        verify_repeater_in.header.status = FW_HDCP_STATUS_SUCCESS;
        verify_repeater_in.header.buffer_len =
                                        WIRED_CMD_BUF_LEN_VERIFY_REPEATER_IN;

        verify_repeater_in.port.integrated_port_type = data->port_type;
        verify_repeater_in.port.physical_port = (u8)data->hdcp_ddi;
        verify_repeater_in.port.attached_transcoder = (u8)data->hdcp_transcoder;

        memcpy(verify_repeater_in.rx_info, rep_topology->rx_info,
               HDCP_2_2_RXINFO_LEN);
        memcpy(verify_repeater_in.seq_num_v, rep_topology->seq_num_v,
               HDCP_2_2_SEQ_NUM_LEN);
        memcpy(verify_repeater_in.v_prime, rep_topology->v_prime,
               HDCP_2_2_V_PRIME_HALF_LEN);
        memcpy(verify_repeater_in.receiver_ids, rep_topology->receiver_ids,
               HDCP_2_2_RECEIVER_IDS_MAX_LEN);

        byte = mei_cldev_send(cldev, (u8 *)&verify_repeater_in,
                              sizeof(verify_repeater_in));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
                return byte;
        }

        byte = mei_cldev_recv(cldev, (u8 *)&verify_repeater_out,
                              sizeof(verify_repeater_out));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
                return byte;
        }

        if (verify_repeater_out.header.status != FW_HDCP_STATUS_SUCCESS) {
                dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
                        WIRED_VERIFY_REPEATER,
                        verify_repeater_out.header.status);
                return -EIO;
        }

        memcpy(rep_send_ack->v, verify_repeater_out.v,
               HDCP_2_2_V_PRIME_HALF_LEN);
        rep_send_ack->msg_id = HDCP_2_2_REP_SEND_ACK;

        return 0;
}

/**
 * mei_hdcp_verify_mprime() - Verify mprime.
 * @dev: device corresponding to the mei_cl_device
 * @data: Intel HW specific hdcp data
 * @stream_ready: RepeaterAuth_Stream_Ready msg for ME FW verification.
 *
 * Return: 0 on Success, <0 on Failure
 */
static int mei_hdcp_verify_mprime(struct device *dev,
                                  struct hdcp_port_data *data,
                                  struct hdcp2_rep_stream_ready *stream_ready)
{
        struct wired_cmd_repeater_auth_stream_req_in *verify_mprime_in;
        struct wired_cmd_repeater_auth_stream_req_out
                                        verify_mprime_out = { { 0 } };
        struct mei_cl_device *cldev;
        ssize_t byte;
        size_t cmd_size;

        if (!dev || !stream_ready || !data)
                return -EINVAL;

        cldev = to_mei_cl_device(dev);

        cmd_size = struct_size(verify_mprime_in, streams, data->k);
        if (cmd_size == SIZE_MAX)
                return -EINVAL;

        verify_mprime_in = kzalloc(cmd_size, GFP_KERNEL);
        if (!verify_mprime_in)
                return -ENOMEM;

        verify_mprime_in->header.api_version = HDCP_API_VERSION;
        verify_mprime_in->header.command_id = WIRED_REPEATER_AUTH_STREAM_REQ;
        verify_mprime_in->header.status = FW_HDCP_STATUS_SUCCESS;
        verify_mprime_in->header.buffer_len = cmd_size  - sizeof(verify_mprime_in->header);

        verify_mprime_in->port.integrated_port_type = data->port_type;
        verify_mprime_in->port.physical_port = (u8)data->hdcp_ddi;
        verify_mprime_in->port.attached_transcoder = (u8)data->hdcp_transcoder;

        memcpy(verify_mprime_in->m_prime, stream_ready->m_prime, HDCP_2_2_MPRIME_LEN);
        drm_hdcp_cpu_to_be24(verify_mprime_in->seq_num_m, data->seq_num_m);

        memcpy(verify_mprime_in->streams, data->streams,
               array_size(data->k, sizeof(*data->streams)));

        verify_mprime_in->k = cpu_to_be16(data->k);

        byte = mei_cldev_send(cldev, (u8 *)verify_mprime_in, cmd_size);
        kfree(verify_mprime_in);
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
                return byte;
        }

        byte = mei_cldev_recv(cldev, (u8 *)&verify_mprime_out,
                              sizeof(verify_mprime_out));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
                return byte;
        }

        if (verify_mprime_out.header.status != FW_HDCP_STATUS_SUCCESS) {
                dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
                        WIRED_REPEATER_AUTH_STREAM_REQ,
                        verify_mprime_out.header.status);
                return -EIO;
        }

        return 0;
}

/**
 * mei_hdcp_enable_authentication() - Mark a port as authenticated
 * through ME FW
 * @dev: device corresponding to the mei_cl_device
 * @data: Intel HW specific hdcp data
 *
 * Return: 0 on Success, <0 on Failure
 */
static int mei_hdcp_enable_authentication(struct device *dev,
                                          struct hdcp_port_data *data)
{
        struct wired_cmd_enable_auth_in enable_auth_in = { { 0 } };
        struct wired_cmd_enable_auth_out enable_auth_out = { { 0 } };
        struct mei_cl_device *cldev;
        ssize_t byte;

        if (!dev || !data)
                return -EINVAL;

        cldev = to_mei_cl_device(dev);

        enable_auth_in.header.api_version = HDCP_API_VERSION;
        enable_auth_in.header.command_id = WIRED_ENABLE_AUTH;
        enable_auth_in.header.status = FW_HDCP_STATUS_SUCCESS;
        enable_auth_in.header.buffer_len = WIRED_CMD_BUF_LEN_ENABLE_AUTH_IN;

        enable_auth_in.port.integrated_port_type = data->port_type;
        enable_auth_in.port.physical_port = (u8)data->hdcp_ddi;
        enable_auth_in.port.attached_transcoder = (u8)data->hdcp_transcoder;
        enable_auth_in.stream_type = data->streams[0].stream_type;

        byte = mei_cldev_send(cldev, (u8 *)&enable_auth_in,
                              sizeof(enable_auth_in));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
                return byte;
        }

        byte = mei_cldev_recv(cldev, (u8 *)&enable_auth_out,
                              sizeof(enable_auth_out));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
                return byte;
        }

        if (enable_auth_out.header.status != FW_HDCP_STATUS_SUCCESS) {
                dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
                        WIRED_ENABLE_AUTH, enable_auth_out.header.status);
                return -EIO;
        }

        return 0;
}

/**
 * mei_hdcp_close_session() - Close the Wired HDCP Tx session of ME FW per port.
 * This also disables the authenticated state of the port.
 * @dev: device corresponding to the mei_cl_device
 * @data: Intel HW specific hdcp data
 *
 * Return: 0 on Success, <0 on Failure
 */
static int
mei_hdcp_close_session(struct device *dev, struct hdcp_port_data *data)
{
        struct wired_cmd_close_session_in session_close_in = { { 0 } };
        struct wired_cmd_close_session_out session_close_out = { { 0 } };
        struct mei_cl_device *cldev;
        ssize_t byte;

        if (!dev || !data)
                return -EINVAL;

        cldev = to_mei_cl_device(dev);

        session_close_in.header.api_version = HDCP_API_VERSION;
        session_close_in.header.command_id = WIRED_CLOSE_SESSION;
        session_close_in.header.status = FW_HDCP_STATUS_SUCCESS;
        session_close_in.header.buffer_len =
                                WIRED_CMD_BUF_LEN_CLOSE_SESSION_IN;

        session_close_in.port.integrated_port_type = data->port_type;
        session_close_in.port.physical_port = (u8)data->hdcp_ddi;
        session_close_in.port.attached_transcoder = (u8)data->hdcp_transcoder;

        byte = mei_cldev_send(cldev, (u8 *)&session_close_in,
                              sizeof(session_close_in));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
                return byte;
        }

        byte = mei_cldev_recv(cldev, (u8 *)&session_close_out,
                              sizeof(session_close_out));
        if (byte < 0) {
                dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
                return byte;
        }

        if (session_close_out.header.status != FW_HDCP_STATUS_SUCCESS) {
                dev_dbg(dev, "Session Close Failed. status: 0x%X\n",
                        session_close_out.header.status);
                return -EIO;
        }

        return 0;
}

static const struct i915_hdcp_ops mei_hdcp_ops = {
        .owner = THIS_MODULE,
        .initiate_hdcp2_session = mei_hdcp_initiate_session,
        .verify_receiver_cert_prepare_km =
                                mei_hdcp_verify_receiver_cert_prepare_km,
        .verify_hprime = mei_hdcp_verify_hprime,
        .store_pairing_info = mei_hdcp_store_pairing_info,
        .initiate_locality_check = mei_hdcp_initiate_locality_check,
        .verify_lprime = mei_hdcp_verify_lprime,
        .get_session_key = mei_hdcp_get_session_key,
        .repeater_check_flow_prepare_ack =
                                mei_hdcp_repeater_check_flow_prepare_ack,
        .verify_mprime = mei_hdcp_verify_mprime,
        .enable_hdcp_authentication = mei_hdcp_enable_authentication,
        .close_hdcp_session = mei_hdcp_close_session,
};

static int mei_component_master_bind(struct device *dev)
{
        struct mei_cl_device *cldev = to_mei_cl_device(dev);
        struct i915_hdcp_arbiter *comp_arbiter = mei_cldev_get_drvdata(cldev);
        int ret;

        dev_dbg(dev, "%s\n", __func__);
        comp_arbiter->ops = &mei_hdcp_ops;
        comp_arbiter->hdcp_dev = dev;
        ret = component_bind_all(dev, comp_arbiter);
        if (ret < 0)
                return ret;

        return 0;
}

static void mei_component_master_unbind(struct device *dev)
{
        struct mei_cl_device *cldev = to_mei_cl_device(dev);
        struct i915_hdcp_arbiter *comp_arbiter = mei_cldev_get_drvdata(cldev);

        dev_dbg(dev, "%s\n", __func__);
        component_unbind_all(dev, comp_arbiter);
}

static const struct component_master_ops mei_component_master_ops = {
        .bind = mei_component_master_bind,
        .unbind = mei_component_master_unbind,
};

/**
 * mei_hdcp_component_match - compare function for matching mei hdcp.
 *
 *    The function checks if the driver is i915, the subcomponent is HDCP
 *    and the grand parent of hdcp and the parent of i915 are the same
 *    PCH device.
 *
 * @dev: master device
 * @subcomponent: subcomponent to match (I915_COMPONENT_HDCP)
 * @data: compare data (mei hdcp device)
 *
 * Return:
 * * 1 - if components match
 * * 0 - otherwise
 */
static int mei_hdcp_component_match(struct device *dev, int subcomponent,
                                    void *data)
{
        struct device *base = data;
        struct pci_dev *pdev;

        if (!dev_is_pci(dev))
                return 0;

        pdev = to_pci_dev(dev);

        if (pdev->class != (PCI_CLASS_DISPLAY_VGA << 8) ||
            pdev->vendor != PCI_VENDOR_ID_INTEL)
                return 0;

        if (subcomponent != I915_COMPONENT_HDCP)
                return 0;

        base = base->parent;
        if (!base)
                return 0;

        base = base->parent;
        dev = dev->parent;

        return (base && dev && dev == base);
}

static int mei_hdcp_probe(struct mei_cl_device *cldev,
                          const struct mei_cl_device_id *id)
{
        struct i915_hdcp_arbiter *comp_arbiter;
        struct component_match *master_match;
        int ret;

        ret = mei_cldev_enable(cldev);
        if (ret < 0) {
                dev_err(&cldev->dev, "mei_cldev_enable Failed. %d\n", ret);
                goto enable_err_exit;
        }

        comp_arbiter = kzalloc_obj(*comp_arbiter);
        if (!comp_arbiter) {
                ret = -ENOMEM;
                goto err_exit;
        }

        master_match = NULL;
        component_match_add_typed(&cldev->dev, &master_match,
                                  mei_hdcp_component_match, &cldev->dev);
        if (IS_ERR_OR_NULL(master_match)) {
                ret = -ENOMEM;
                goto err_exit;
        }

        mei_cldev_set_drvdata(cldev, comp_arbiter);
        ret = component_master_add_with_match(&cldev->dev,
                                              &mei_component_master_ops,
                                              master_match);
        if (ret < 0) {
                dev_err(&cldev->dev, "Master comp add failed %d\n", ret);
                goto err_exit;
        }

        return 0;

err_exit:
        mei_cldev_set_drvdata(cldev, NULL);
        kfree(comp_arbiter);
        mei_cldev_disable(cldev);
enable_err_exit:
        return ret;
}

static void mei_hdcp_remove(struct mei_cl_device *cldev)
{
        struct i915_hdcp_arbiter *comp_arbiter = mei_cldev_get_drvdata(cldev);
        int ret;

        component_master_del(&cldev->dev, &mei_component_master_ops);
        kfree(comp_arbiter);
        mei_cldev_set_drvdata(cldev, NULL);

        ret = mei_cldev_disable(cldev);
        if (ret)
                dev_warn(&cldev->dev, "mei_cldev_disable() failed\n");
}

#define MEI_UUID_HDCP UUID_LE(0xB638AB7E, 0x94E2, 0x4EA2, 0xA5, \
                              0x52, 0xD1, 0xC5, 0x4B, 0x62, 0x7F, 0x04)

static const struct mei_cl_device_id mei_hdcp_tbl[] = {
        { .uuid = MEI_UUID_HDCP, .version = MEI_CL_VERSION_ANY },
        { }
};
MODULE_DEVICE_TABLE(mei, mei_hdcp_tbl);

static struct mei_cl_driver mei_hdcp_driver = {
        .id_table = mei_hdcp_tbl,
        .name = KBUILD_MODNAME,
        .probe = mei_hdcp_probe,
        .remove = mei_hdcp_remove,
};

module_mei_cl_driver(mei_hdcp_driver);

MODULE_AUTHOR("Intel Corporation");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MEI HDCP");