// SPDX-License-Identifier: GPL-2.0-only
/*
 * ISHTP client driver for HID (ISH)
 *
 * Copyright (c) 2014-2016, Intel Corporation.
 */

#include <linux/module.h>
#include <linux/hid.h>
#include <linux/intel-ish-client-if.h>
#include <linux/sched.h>
#include "ishtp-hid.h"

/* ISH Transport protocol (ISHTP in short) GUID */
static const struct ishtp_device_id hid_ishtp_id_table[] = {
        { .guid = GUID_INIT(0x33AECD58, 0xB679, 0x4E54,
                  0x9B, 0xD9, 0xA0, 0x4D, 0x34, 0xF0, 0xC2, 0x26), },
        { }
};
MODULE_DEVICE_TABLE(ishtp, hid_ishtp_id_table);

/* Rx ring buffer pool size */
#define HID_CL_RX_RING_SIZE     32
#define HID_CL_TX_RING_SIZE     16

#define cl_data_to_dev(client_data) ishtp_device(client_data->cl_device)

/**
 * report_bad_packet() - Report bad packets
 * @hid_ishtp_cl:       Client instance to get stats
 * @recv_buf:           Raw received host interface message
 * @cur_pos:            Current position index in payload
 * @payload_len:        Length of payload expected
 *
 * Dumps error in case bad packet is received
 */
static void report_bad_packet(struct ishtp_cl *hid_ishtp_cl, void *recv_buf,
                              size_t cur_pos,  size_t payload_len)
{
        struct hostif_msg *recv_msg = recv_buf;
        struct ishtp_cl_data *client_data = ishtp_get_client_data(hid_ishtp_cl);

        dev_err(cl_data_to_dev(client_data), "[hid-ish]: BAD packet %02X\n"
                "total_bad=%u cur_pos=%u\n"
                "[%02X %02X %02X %02X]\n"
                "payload_len=%u\n"
                "multi_packet_cnt=%u\n"
                "is_response=%02X\n",
                recv_msg->hdr.command, client_data->bad_recv_cnt,
                (unsigned int)cur_pos,
                ((unsigned char *)recv_msg)[0], ((unsigned char *)recv_msg)[1],
                ((unsigned char *)recv_msg)[2], ((unsigned char *)recv_msg)[3],
                (unsigned int)payload_len, client_data->multi_packet_cnt,
                recv_msg->hdr.command & ~CMD_MASK);
}

/**
 * process_recv() - Received and parse incoming packet
 * @hid_ishtp_cl:       Client instance to get stats
 * @recv_buf:           Raw received host interface message
 * @data_len:           length of the message
 *
 * Parse the incoming packet. If it is a response packet then it will update
 * per instance flags and wake up the caller waiting to for the response.
 */
static void process_recv(struct ishtp_cl *hid_ishtp_cl, void *recv_buf,
                         size_t data_len)
{
        struct hostif_msg *recv_msg;
        unsigned char *payload;
        struct device_info *dev_info;
        int i, j;
        size_t  payload_len, total_len, cur_pos, raw_len;
        int report_type;
        struct report_list *reports_list;
        char *reports;
        size_t report_len;
        struct ishtp_cl_data *client_data = ishtp_get_client_data(hid_ishtp_cl);
        int curr_hid_dev = client_data->cur_hid_dev;
        struct ishtp_hid_data *hid_data = NULL;
        struct hid_device *hid = NULL;

        payload = recv_buf + sizeof(struct hostif_msg_hdr);
        total_len = data_len;
        cur_pos = 0;

        do {
                if (cur_pos + sizeof(struct hostif_msg) > total_len) {
                        dev_err(cl_data_to_dev(client_data),
                                "[hid-ish]: error, received %u which is less than data header %u\n",
                                (unsigned int)data_len,
                                (unsigned int)sizeof(struct hostif_msg_hdr));
                        ++client_data->bad_recv_cnt;
                        ish_hw_reset(ishtp_get_ishtp_device(hid_ishtp_cl));
                        break;
                }

                recv_msg = (struct hostif_msg *)(recv_buf + cur_pos);
                payload_len = recv_msg->hdr.size;

                /* Sanity checks */
                if (cur_pos + payload_len + sizeof(struct hostif_msg) >
                                total_len) {
                        ++client_data->bad_recv_cnt;
                        report_bad_packet(hid_ishtp_cl, recv_msg, cur_pos,
                                          payload_len);
                        ish_hw_reset(ishtp_get_ishtp_device(hid_ishtp_cl));
                        break;
                }

                hid_ishtp_trace(client_data,  "%s %d\n",
                                __func__, recv_msg->hdr.command & CMD_MASK);

                switch (recv_msg->hdr.command & CMD_MASK) {
                case HOSTIF_DM_ENUM_DEVICES:
                        if ((!(recv_msg->hdr.command & ~CMD_MASK) ||
                                        client_data->init_done)) {
                                ++client_data->bad_recv_cnt;
                                report_bad_packet(hid_ishtp_cl, recv_msg,
                                                  cur_pos,
                                                  payload_len);
                                ish_hw_reset(ishtp_get_ishtp_device(hid_ishtp_cl));
                                break;
                        }
                        client_data->hid_dev_count = (unsigned int)*payload;
                        if (!client_data->hid_devices)
                                client_data->hid_devices = devm_kcalloc(
                                                cl_data_to_dev(client_data),
                                                client_data->hid_dev_count,
                                                sizeof(struct device_info),
                                                GFP_KERNEL);
                        if (!client_data->hid_devices) {
                                dev_err(cl_data_to_dev(client_data),
                                "Mem alloc failed for hid device info\n");
                                wake_up_interruptible(&client_data->init_wait);
                                break;
                        }
                        for (i = 0; i < client_data->hid_dev_count; ++i) {
                                if (1 + sizeof(struct device_info) * i >=
                                                payload_len) {
                                        dev_err(cl_data_to_dev(client_data),
                                                "[hid-ish]: [ENUM_DEVICES]: content size %zu is bigger than payload_len %zu\n",
                                                1 + sizeof(struct device_info)
                                                * i, payload_len);
                                }

                                if (1 + sizeof(struct device_info) * i >=
                                                data_len)
                                        break;

                                dev_info = (struct device_info *)(payload + 1 +
                                        sizeof(struct device_info) * i);
                                if (client_data->hid_devices)
                                        memcpy(client_data->hid_devices + i,
                                               dev_info,
                                               sizeof(struct device_info));
                        }

                        client_data->enum_devices_done = true;
                        wake_up_interruptible(&client_data->init_wait);

                        break;

                case HOSTIF_GET_HID_DESCRIPTOR:
                        if ((!(recv_msg->hdr.command & ~CMD_MASK) ||
                                        client_data->init_done)) {
                                ++client_data->bad_recv_cnt;
                                report_bad_packet(hid_ishtp_cl, recv_msg,
                                                  cur_pos,
                                                  payload_len);
                                ish_hw_reset(ishtp_get_ishtp_device(hid_ishtp_cl));
                                break;
                        }
                        if (!client_data->hid_descr[curr_hid_dev])
                                client_data->hid_descr[curr_hid_dev] =
                                devm_kmalloc(cl_data_to_dev(client_data),
                                             payload_len, GFP_KERNEL);
                        if (client_data->hid_descr[curr_hid_dev]) {
                                memcpy(client_data->hid_descr[curr_hid_dev],
                                       payload, payload_len);
                                client_data->hid_descr_size[curr_hid_dev] =
                                        payload_len;
                                client_data->hid_descr_done = true;
                        }
                        wake_up_interruptible(&client_data->init_wait);

                        break;

                case HOSTIF_GET_REPORT_DESCRIPTOR:
                        if ((!(recv_msg->hdr.command & ~CMD_MASK) ||
                                        client_data->init_done)) {
                                ++client_data->bad_recv_cnt;
                                report_bad_packet(hid_ishtp_cl, recv_msg,
                                                  cur_pos,
                                                  payload_len);
                                ish_hw_reset(ishtp_get_ishtp_device(hid_ishtp_cl));
                                break;
                        }
                        if (!client_data->report_descr[curr_hid_dev])
                                client_data->report_descr[curr_hid_dev] =
                                devm_kmalloc(cl_data_to_dev(client_data),
                                             payload_len, GFP_KERNEL);
                        if (client_data->report_descr[curr_hid_dev])  {
                                memcpy(client_data->report_descr[curr_hid_dev],
                                       payload,
                                       payload_len);
                                client_data->report_descr_size[curr_hid_dev] =
                                        payload_len;
                                client_data->report_descr_done = true;
                        }
                        wake_up_interruptible(&client_data->init_wait);

                        break;

                case HOSTIF_GET_FEATURE_REPORT:
                        report_type = HID_FEATURE_REPORT;
                        goto    do_get_report;

                case HOSTIF_GET_INPUT_REPORT:
                        report_type = HID_INPUT_REPORT;
do_get_report:
                        /* Get index of device that matches this id */
                        for (i = 0; i < client_data->num_hid_devices; ++i) {
                                if (recv_msg->hdr.device_id ==
                                          client_data->hid_devices[i].dev_id) {
                                        hid = client_data->hid_sensor_hubs[i];
                                        if (!hid)
                                                break;

                                        hid_data = hid->driver_data;
                                        if (hid_data->raw_get_req) {
                                                raw_len =
                                                  (hid_data->raw_buf_size <
                                                                payload_len) ?
                                                  hid_data->raw_buf_size :
                                                  payload_len;

                                                memcpy(hid_data->raw_buf,
                                                       payload, raw_len);
                                        } else {
                                                hid_input_report
                                                        (hid, report_type,
                                                         payload, payload_len,
                                                         0);
                                        }

                                        ishtp_hid_wakeup(hid);
                                        break;
                                }
                        }
                        break;

                case HOSTIF_SET_FEATURE_REPORT:
                        /* Get index of device that matches this id */
                        for (i = 0; i < client_data->num_hid_devices; ++i) {
                                if (recv_msg->hdr.device_id ==
                                        client_data->hid_devices[i].dev_id)
                                        if (client_data->hid_sensor_hubs[i]) {
                                                ishtp_hid_wakeup(
                                                client_data->hid_sensor_hubs[
                                                        i]);
                                                break;
                                        }
                        }
                        break;

                case HOSTIF_PUBLISH_INPUT_REPORT:
                        report_type = HID_INPUT_REPORT;
                        for (i = 0; i < client_data->num_hid_devices; ++i)
                                if (recv_msg->hdr.device_id ==
                                        client_data->hid_devices[i].dev_id)
                                        if (client_data->hid_sensor_hubs[i])
                                                hid_input_report(
                                                client_data->hid_sensor_hubs[
                                                                        i],
                                                report_type, payload,
                                                payload_len, 0);
                        break;

                case HOSTIF_PUBLISH_INPUT_REPORT_LIST:
                        report_type = HID_INPUT_REPORT;
                        reports_list = (struct report_list *)payload;
                        reports = (char *)reports_list->reports;

                        for (j = 0; j < reports_list->num_of_reports; j++) {
                                recv_msg = (struct hostif_msg *)(reports +
                                        sizeof(uint16_t));
                                report_len = *(uint16_t *)reports;
                                payload = reports + sizeof(uint16_t) +
                                        sizeof(struct hostif_msg_hdr);
                                payload_len = report_len -
                                        sizeof(struct hostif_msg_hdr);

                                for (i = 0; i < client_data->num_hid_devices;
                                     ++i)
                                        if (recv_msg->hdr.device_id ==
                                        client_data->hid_devices[i].dev_id &&
                                        client_data->hid_sensor_hubs[i]) {
                                                hid_input_report(
                                                client_data->hid_sensor_hubs[
                                                                        i],
                                                report_type,
                                                payload, payload_len,
                                                0);
                                        }

                                reports += sizeof(uint16_t) + report_len;
                        }
                        break;
                default:
                        ++client_data->bad_recv_cnt;
                        report_bad_packet(hid_ishtp_cl, recv_msg, cur_pos,
                                          payload_len);
                        ish_hw_reset(ishtp_get_ishtp_device(hid_ishtp_cl));
                        break;

                }

                if (!cur_pos && cur_pos + payload_len +
                                sizeof(struct hostif_msg) < total_len)
                        ++client_data->multi_packet_cnt;

                cur_pos += payload_len + sizeof(struct hostif_msg);
                payload += payload_len + sizeof(struct hostif_msg);

        } while (cur_pos < total_len);
}

/**
 * ish_cl_event_cb() - bus driver callback for incoming message/packet
 * @device:     Pointer to the the ishtp client device for which this message
 *              is targeted
 *
 * Remove the packet from the list and process the message by calling
 * process_recv
 */
static void ish_cl_event_cb(struct ishtp_cl_device *device)
{
        struct ishtp_cl *hid_ishtp_cl = ishtp_get_drvdata(device);
        struct ishtp_cl_rb *rb_in_proc;
        size_t r_length;

        if (!hid_ishtp_cl)
                return;

        while ((rb_in_proc = ishtp_cl_rx_get_rb(hid_ishtp_cl)) != NULL) {
                if (!rb_in_proc->buffer.data)
                        return;

                r_length = rb_in_proc->buf_idx;

                /* decide what to do with received data */
                process_recv(hid_ishtp_cl, rb_in_proc->buffer.data, r_length);

                ishtp_cl_io_rb_recycle(rb_in_proc);
        }
}

/**
 * hid_ishtp_set_feature() - send request to ISH FW to set a feature request
 * @hid:        hid device instance for this request
 * @buf:        feature buffer
 * @len:        Length of feature buffer
 * @report_id:  Report id for the feature set request
 *
 * This is called from hid core .request() callback. This function doesn't wait
 * for response.
 */
void hid_ishtp_set_feature(struct hid_device *hid, char *buf, unsigned int len,
                           int report_id)
{
        struct ishtp_hid_data *hid_data =  hid->driver_data;
        struct ishtp_cl_data *client_data = hid_data->client_data;
        struct hostif_msg *msg = (struct hostif_msg *)buf;
        int     rv;
        int     i;

        hid_ishtp_trace(client_data,  "%s hid %p\n", __func__, hid);

        rv = ishtp_hid_link_ready_wait(client_data);
        if (rv) {
                hid_ishtp_trace(client_data,  "%s hid %p link not ready\n",
                                __func__, hid);
                return;
        }

        memset(msg, 0, sizeof(struct hostif_msg));
        msg->hdr.command = HOSTIF_SET_FEATURE_REPORT;
        for (i = 0; i < client_data->num_hid_devices; ++i) {
                if (hid == client_data->hid_sensor_hubs[i]) {
                        msg->hdr.device_id =
                                client_data->hid_devices[i].dev_id;
                        break;
                }
        }

        if (i == client_data->num_hid_devices)
                return;

        rv = ishtp_cl_send(client_data->hid_ishtp_cl, buf, len);
        if (rv)
                hid_ishtp_trace(client_data,  "%s hid %p send failed\n",
                                __func__, hid);
}

/**
 * hid_ishtp_get_report() - request to get feature/input report
 * @hid:        hid device instance for this request
 * @report_id:  Report id for the get request
 * @report_type:        Report type for the this request
 *
 * This is called from hid core .request() callback. This function will send
 * request to FW and return without waiting for response.
 */
void hid_ishtp_get_report(struct hid_device *hid, int report_id,
                          int report_type)
{
        struct ishtp_hid_data *hid_data =  hid->driver_data;
        struct ishtp_cl_data *client_data = hid_data->client_data;
        struct hostif_msg_to_sensor msg = {};
        int     rv;
        int     i;

        hid_ishtp_trace(client_data,  "%s hid %p\n", __func__, hid);
        rv = ishtp_hid_link_ready_wait(client_data);
        if (rv) {
                hid_ishtp_trace(client_data,  "%s hid %p link not ready\n",
                                __func__, hid);
                return;
        }

        msg.hdr.command = (report_type == HID_FEATURE_REPORT) ?
                HOSTIF_GET_FEATURE_REPORT : HOSTIF_GET_INPUT_REPORT;
        for (i = 0; i < client_data->num_hid_devices; ++i) {
                if (hid == client_data->hid_sensor_hubs[i]) {
                        msg.hdr.device_id =
                                client_data->hid_devices[i].dev_id;
                        break;
                }
        }

        if (i == client_data->num_hid_devices)
                return;

        msg.report_id = report_id;
        rv = ishtp_cl_send(client_data->hid_ishtp_cl, (uint8_t *)&msg,
                            sizeof(msg));
        if (rv)
                hid_ishtp_trace(client_data,  "%s hid %p send failed\n",
                                __func__, hid);
}

/**
 * ishtp_hid_link_ready_wait() - Wait for link ready
 * @client_data:        client data instance
 *
 * If the transport link started suspend process, then wait, till either
 * resumed or timeout
 *
 * Return: 0 on success, non zero on error
 */
int ishtp_hid_link_ready_wait(struct ishtp_cl_data *client_data)
{
        int rc;

        if (client_data->suspended) {
                hid_ishtp_trace(client_data,  "wait for link ready\n");
                rc = wait_event_interruptible_timeout(
                                        client_data->ishtp_resume_wait,
                                        !client_data->suspended,
                                        5 * HZ);

                if (rc == 0) {
                        hid_ishtp_trace(client_data,  "link not ready\n");
                        return -EIO;
                }
                hid_ishtp_trace(client_data,  "link ready\n");
        }

        return 0;
}

/**
 * ishtp_enum_enum_devices() - Enumerate hid devices
 * @hid_ishtp_cl:       client instance
 *
 * Helper function to send request to firmware to enumerate HID devices
 *
 * Return: 0 on success, non zero on error
 */
static int ishtp_enum_enum_devices(struct ishtp_cl *hid_ishtp_cl)
{
        struct hostif_msg msg;
        struct ishtp_cl_data *client_data = ishtp_get_client_data(hid_ishtp_cl);
        int retry_count;
        int rv;

        /* Send HOSTIF_DM_ENUM_DEVICES */
        memset(&msg, 0, sizeof(struct hostif_msg));
        msg.hdr.command = HOSTIF_DM_ENUM_DEVICES;
        rv = ishtp_cl_send(hid_ishtp_cl, (unsigned char *)&msg,
                           sizeof(struct hostif_msg));
        if (rv)
                return rv;

        retry_count = 0;
        while (!client_data->enum_devices_done &&
               retry_count < 10) {
                wait_event_interruptible_timeout(client_data->init_wait,
                                         client_data->enum_devices_done,
                                         3 * HZ);
                ++retry_count;
                if (!client_data->enum_devices_done)
                        /* Send HOSTIF_DM_ENUM_DEVICES */
                        rv = ishtp_cl_send(hid_ishtp_cl,
                                           (unsigned char *) &msg,
                                           sizeof(struct hostif_msg));
        }
        if (!client_data->enum_devices_done) {
                dev_err(cl_data_to_dev(client_data),
                        "[hid-ish]: timed out waiting for enum_devices\n");
                return -ETIMEDOUT;
        }
        if (!client_data->hid_devices) {
                dev_err(cl_data_to_dev(client_data),
                        "[hid-ish]: failed to allocate HID dev structures\n");
                return -ENOMEM;
        }

        client_data->num_hid_devices = client_data->hid_dev_count;
        dev_info(ishtp_device(client_data->cl_device),
                "[hid-ish]: enum_devices_done OK, num_hid_devices=%d\n",
                client_data->num_hid_devices);

        return  0;
}

/**
 * ishtp_get_hid_descriptor() - Get hid descriptor
 * @hid_ishtp_cl:       client instance
 * @index:              Index into the hid_descr array
 *
 * Helper function to send request to firmware get HID descriptor of a device
 *
 * Return: 0 on success, non zero on error
 */
static int ishtp_get_hid_descriptor(struct ishtp_cl *hid_ishtp_cl, int index)
{
        struct hostif_msg msg;
        struct ishtp_cl_data *client_data = ishtp_get_client_data(hid_ishtp_cl);
        int rv;

        /* Get HID descriptor */
        client_data->hid_descr_done = false;
        memset(&msg, 0, sizeof(struct hostif_msg));
        msg.hdr.command = HOSTIF_GET_HID_DESCRIPTOR;
        msg.hdr.device_id = client_data->hid_devices[index].dev_id;
        rv = ishtp_cl_send(hid_ishtp_cl, (unsigned char *) &msg,
                           sizeof(struct hostif_msg));
        if (rv)
                return rv;

        if (!client_data->hid_descr_done) {
                wait_event_interruptible_timeout(client_data->init_wait,
                                                 client_data->hid_descr_done,
                                                 3 * HZ);
                if (!client_data->hid_descr_done) {
                        dev_err(cl_data_to_dev(client_data),
                                "[hid-ish]: timed out for hid_descr_done\n");
                        return -EIO;
                }

                if (!client_data->hid_descr[index]) {
                        dev_err(cl_data_to_dev(client_data),
                                "[hid-ish]: allocation HID desc fail\n");
                        return -ENOMEM;
                }
        }

        return 0;
}

/**
 * ishtp_get_report_descriptor() - Get report descriptor
 * @hid_ishtp_cl:       client instance
 * @index:              Index into the hid_descr array
 *
 * Helper function to send request to firmware get HID report descriptor of
 * a device
 *
 * Return: 0 on success, non zero on error
 */
static int ishtp_get_report_descriptor(struct ishtp_cl *hid_ishtp_cl,
                                       int index)
{
        struct hostif_msg msg;
        struct ishtp_cl_data *client_data = ishtp_get_client_data(hid_ishtp_cl);
        int rv;

        /* Get report descriptor */
        client_data->report_descr_done = false;
        memset(&msg, 0, sizeof(struct hostif_msg));
        msg.hdr.command = HOSTIF_GET_REPORT_DESCRIPTOR;
        msg.hdr.device_id = client_data->hid_devices[index].dev_id;
        rv = ishtp_cl_send(hid_ishtp_cl, (unsigned char *) &msg,
                           sizeof(struct hostif_msg));
        if (rv)
                return rv;

        if (!client_data->report_descr_done)
                wait_event_interruptible_timeout(client_data->init_wait,
                                         client_data->report_descr_done,
                                         3 * HZ);
        if (!client_data->report_descr_done) {
                dev_err(cl_data_to_dev(client_data),
                                "[hid-ish]: timed out for report descr\n");
                return -EIO;
        }
        if (!client_data->report_descr[index]) {
                dev_err(cl_data_to_dev(client_data),
                        "[hid-ish]: failed to alloc report descr\n");
                return -ENOMEM;
        }

        return 0;
}

/**
 * hid_ishtp_cl_init() - Init function for ISHTP client
 * @hid_ishtp_cl:       ISHTP client instance
 * @reset:              true if called for init after reset
 *
 * This function complete the initializtion of the client. The summary of
 * processing:
 * - Send request to enumerate the hid clients
 *      Get the HID descriptor for each enumearated device
 *      Get report description of each device
 *      Register each device wik hid core by calling ishtp_hid_probe
 *
 * Return: 0 on success, non zero on error
 */
static int hid_ishtp_cl_init(struct ishtp_cl *hid_ishtp_cl, int reset)
{
        struct ishtp_device *dev;
        struct ishtp_cl_data *client_data = ishtp_get_client_data(hid_ishtp_cl);
        struct ishtp_fw_client *fw_client;
        int i;
        int rv;

        dev_dbg(cl_data_to_dev(client_data), "%s\n", __func__);
        hid_ishtp_trace(client_data,  "%s reset flag: %d\n", __func__, reset);

        rv = ishtp_cl_link(hid_ishtp_cl);
        if (rv) {
                dev_err(cl_data_to_dev(client_data),
                        "ishtp_cl_link failed\n");
                return  -ENOMEM;
        }

        client_data->init_done = 0;

        dev = ishtp_get_ishtp_device(hid_ishtp_cl);

        /* Connect to FW client */
        ishtp_set_tx_ring_size(hid_ishtp_cl, HID_CL_TX_RING_SIZE);
        ishtp_set_rx_ring_size(hid_ishtp_cl, HID_CL_RX_RING_SIZE);

        fw_client = ishtp_fw_cl_get_client(dev, &hid_ishtp_id_table[0].guid);
        if (!fw_client) {
                dev_err(cl_data_to_dev(client_data),
                        "ish client uuid not found\n");
                return -ENOENT;
        }
        ishtp_cl_set_fw_client_id(hid_ishtp_cl,
                                  ishtp_get_fw_client_id(fw_client));
        ishtp_set_connection_state(hid_ishtp_cl, ISHTP_CL_CONNECTING);

        rv = ishtp_cl_connect(hid_ishtp_cl);
        if (rv) {
                dev_err(cl_data_to_dev(client_data),
                        "client connect fail\n");
                goto err_cl_unlink;
        }

        hid_ishtp_trace(client_data,  "%s client connected\n", __func__);

        /* Register read callback */
        ishtp_register_event_cb(client_data->cl_device, ish_cl_event_cb);

        rv = ishtp_enum_enum_devices(hid_ishtp_cl);
        if (rv)
                goto err_cl_disconnect;

        hid_ishtp_trace(client_data,  "%s enumerated device count %d\n",
                        __func__, client_data->num_hid_devices);

        for (i = 0; i < client_data->num_hid_devices; ++i) {
                client_data->cur_hid_dev = i;

                rv = ishtp_get_hid_descriptor(hid_ishtp_cl, i);
                if (rv)
                        goto err_cl_disconnect;

                rv = ishtp_get_report_descriptor(hid_ishtp_cl, i);
                if (rv)
                        goto err_cl_disconnect;

                if (!reset) {
                        rv = ishtp_hid_probe(i, client_data);
                        if (rv) {
                                dev_err(cl_data_to_dev(client_data),
                                "[hid-ish]: HID probe for #%u failed: %d\n",
                                i, rv);
                                goto err_cl_disconnect;
                        }
                }
        } /* for() on all hid devices */

        client_data->init_done = 1;
        client_data->suspended = false;
        wake_up_interruptible(&client_data->ishtp_resume_wait);
        hid_ishtp_trace(client_data,  "%s successful init\n", __func__);
        return 0;

err_cl_disconnect:
        ishtp_set_connection_state(hid_ishtp_cl, ISHTP_CL_DISCONNECTING);
        ishtp_cl_disconnect(hid_ishtp_cl);
err_cl_unlink:
        ishtp_cl_unlink(hid_ishtp_cl);
        return rv;
}

/**
 * hid_ishtp_cl_deinit() - Deinit function for ISHTP client
 * @hid_ishtp_cl:       ISHTP client instance
 *
 * Unlink and free hid client
 */
static void hid_ishtp_cl_deinit(struct ishtp_cl *hid_ishtp_cl)
{
        ishtp_cl_unlink(hid_ishtp_cl);
        ishtp_cl_flush_queues(hid_ishtp_cl);

        /* disband and free all Tx and Rx client-level rings */
        ishtp_cl_free(hid_ishtp_cl);
}

static void hid_ishtp_cl_reset_handler(struct work_struct *work)
{
        struct ishtp_cl_data *client_data;
        struct ishtp_cl *hid_ishtp_cl;
        struct ishtp_cl_device *cl_device;
        int retry;
        int rv;

        client_data = container_of(work, struct ishtp_cl_data, work);

        hid_ishtp_cl = client_data->hid_ishtp_cl;
        cl_device = client_data->cl_device;

        hid_ishtp_trace(client_data, "%s hid_ishtp_cl %p\n", __func__,
                        hid_ishtp_cl);
        dev_dbg(ishtp_device(client_data->cl_device), "%s\n", __func__);

        hid_ishtp_cl_deinit(hid_ishtp_cl);

        hid_ishtp_cl = ishtp_cl_allocate(cl_device);
        if (!hid_ishtp_cl)
                return;

        ishtp_set_drvdata(cl_device, hid_ishtp_cl);
        ishtp_set_client_data(hid_ishtp_cl, client_data);
        client_data->hid_ishtp_cl = hid_ishtp_cl;

        client_data->num_hid_devices = 0;

        for (retry = 0; retry < 3; ++retry) {
                rv = hid_ishtp_cl_init(hid_ishtp_cl, 1);
                if (!rv)
                        break;
                dev_err(cl_data_to_dev(client_data), "Retry reset init\n");
        }
        if (rv) {
                dev_err(cl_data_to_dev(client_data), "Reset Failed\n");
                hid_ishtp_trace(client_data, "%s Failed hid_ishtp_cl %p\n",
                                __func__, hid_ishtp_cl);
        }
}

static void hid_ishtp_cl_resume_handler(struct work_struct *work)
{
        struct ishtp_cl_data *client_data = container_of(work, struct ishtp_cl_data, resume_work);
        struct ishtp_cl *hid_ishtp_cl = client_data->hid_ishtp_cl;

        if (ishtp_wait_resume(ishtp_get_ishtp_device(hid_ishtp_cl))) {
                client_data->suspended = false;
                wake_up_interruptible(&client_data->ishtp_resume_wait);
        }
}

ishtp_print_log ishtp_hid_print_trace;

/**
 * hid_ishtp_cl_probe() - ISHTP client driver probe
 * @cl_device:          ISHTP client device instance
 *
 * This function gets called on device create on ISHTP bus
 *
 * Return: 0 on success, non zero on error
 */
static int hid_ishtp_cl_probe(struct ishtp_cl_device *cl_device)
{
        struct ishtp_cl *hid_ishtp_cl;
        struct ishtp_cl_data *client_data;
        int rv;

        if (!cl_device)
                return  -ENODEV;

        client_data = devm_kzalloc(ishtp_device(cl_device),
                                   sizeof(*client_data),
                                   GFP_KERNEL);
        if (!client_data)
                return -ENOMEM;

        hid_ishtp_cl = ishtp_cl_allocate(cl_device);
        if (!hid_ishtp_cl)
                return -ENOMEM;

        ishtp_set_drvdata(cl_device, hid_ishtp_cl);
        ishtp_set_client_data(hid_ishtp_cl, client_data);
        client_data->hid_ishtp_cl = hid_ishtp_cl;
        client_data->cl_device = cl_device;

        init_waitqueue_head(&client_data->init_wait);
        init_waitqueue_head(&client_data->ishtp_resume_wait);

        INIT_WORK(&client_data->work, hid_ishtp_cl_reset_handler);
        INIT_WORK(&client_data->resume_work, hid_ishtp_cl_resume_handler);


        ishtp_hid_print_trace = ishtp_trace_callback(cl_device);

        rv = hid_ishtp_cl_init(hid_ishtp_cl, 0);
        if (rv) {
                ishtp_cl_free(hid_ishtp_cl);
                return rv;
        }
        ishtp_get_device(cl_device);

        return 0;
}

/**
 * hid_ishtp_cl_remove() - ISHTP client driver remove
 * @cl_device:          ISHTP client device instance
 *
 * This function gets called on device remove on ISHTP bus
 *
 * Return: 0
 */
static void hid_ishtp_cl_remove(struct ishtp_cl_device *cl_device)
{
        struct ishtp_cl *hid_ishtp_cl = ishtp_get_drvdata(cl_device);
        struct ishtp_cl_data *client_data = ishtp_get_client_data(hid_ishtp_cl);

        hid_ishtp_trace(client_data, "%s hid_ishtp_cl %p\n", __func__,
                        hid_ishtp_cl);

        dev_dbg(ishtp_device(cl_device), "%s\n", __func__);
        ishtp_set_connection_state(hid_ishtp_cl, ISHTP_CL_DISCONNECTING);
        ishtp_cl_disconnect(hid_ishtp_cl);
        ishtp_put_device(cl_device);
        ishtp_hid_remove(client_data);
        hid_ishtp_cl_deinit(hid_ishtp_cl);

        hid_ishtp_cl = NULL;

        client_data->num_hid_devices = 0;
}

/**
 * hid_ishtp_cl_reset() - ISHTP client driver reset
 * @cl_device:          ISHTP client device instance
 *
 * This function gets called on device reset on ISHTP bus
 *
 * Return: 0
 */
static int hid_ishtp_cl_reset(struct ishtp_cl_device *cl_device)
{
        struct ishtp_cl *hid_ishtp_cl = ishtp_get_drvdata(cl_device);
        struct ishtp_cl_data *client_data = ishtp_get_client_data(hid_ishtp_cl);

        hid_ishtp_trace(client_data, "%s hid_ishtp_cl %p\n", __func__,
                        hid_ishtp_cl);

        schedule_work(&client_data->work);

        return 0;
}

/**
 * hid_ishtp_cl_suspend() - ISHTP client driver suspend
 * @device:     device instance
 *
 * This function gets called on system suspend
 *
 * Return: 0
 */
static int hid_ishtp_cl_suspend(struct device *device)
{
        struct ishtp_cl_device *cl_device = ishtp_dev_to_cl_device(device);
        struct ishtp_cl *hid_ishtp_cl = ishtp_get_drvdata(cl_device);
        struct ishtp_cl_data *client_data = ishtp_get_client_data(hid_ishtp_cl);

        hid_ishtp_trace(client_data, "%s hid_ishtp_cl %p\n", __func__,
                        hid_ishtp_cl);
        client_data->suspended = true;

        return 0;
}

/**
 * hid_ishtp_cl_resume() - ISHTP client driver resume
 * @device:     device instance
 *
 * This function gets called on system resume
 *
 * Return: 0
 */
static int hid_ishtp_cl_resume(struct device *device)
{
        struct ishtp_cl_device *cl_device = ishtp_dev_to_cl_device(device);
        struct ishtp_cl *hid_ishtp_cl = ishtp_get_drvdata(cl_device);
        struct ishtp_cl_data *client_data = ishtp_get_client_data(hid_ishtp_cl);

        hid_ishtp_trace(client_data, "%s hid_ishtp_cl %p\n", __func__,
                        hid_ishtp_cl);
        schedule_work(&client_data->resume_work);
        return 0;
}

static const struct dev_pm_ops hid_ishtp_pm_ops = {
        .suspend = hid_ishtp_cl_suspend,
        .resume = hid_ishtp_cl_resume,
};

static struct ishtp_cl_driver   hid_ishtp_cl_driver = {
        .name = "ish-hid",
        .id = hid_ishtp_id_table,
        .probe = hid_ishtp_cl_probe,
        .remove = hid_ishtp_cl_remove,
        .reset = hid_ishtp_cl_reset,
        .driver.pm = &hid_ishtp_pm_ops,
};

static int __init ish_hid_init(void)
{
        int     rv;

        /* Register ISHTP client device driver with ISHTP Bus */
        rv = ishtp_cl_driver_register(&hid_ishtp_cl_driver, THIS_MODULE);

        return rv;

}

static void __exit ish_hid_exit(void)
{
        ishtp_cl_driver_unregister(&hid_ishtp_cl_driver);
}

late_initcall(ish_hid_init);
module_exit(ish_hid_exit);

MODULE_DESCRIPTION("ISH ISHTP HID client driver");
/* Primary author */
MODULE_AUTHOR("Daniel Drubin <daniel.drubin@intel.com>");
/*
 * Several modification for multi instance support
 * suspend/resume and clean up
 */
MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");

MODULE_LICENSE("GPL");