root/drivers/input/touchscreen/melfas_mip4.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * MELFAS MIP4 Touchscreen
 *
 * Copyright (C) 2016 MELFAS Inc.
 *
 * Author : Sangwon Jee <jeesw@melfas.com>
 */

#include <linux/acpi.h>
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/unaligned.h>

#define MIP4_DEVICE_NAME        "mip4_ts"

/*****************************************************************
 * Protocol
 * Version : MIP 4.0 Rev 5.4
 *****************************************************************/

/* Address */
#define MIP4_R0_BOOT                            0x00
#define MIP4_R1_BOOT_MODE                       0x01
#define MIP4_R1_BOOT_BUF_ADDR                   0x10
#define MIP4_R1_BOOT_STATUS                     0x20
#define MIP4_R1_BOOT_CMD                        0x30
#define MIP4_R1_BOOT_TARGET_ADDR                0x40
#define MIP4_R1_BOOT_SIZE                       0x44

#define MIP4_R0_INFO                            0x01
#define MIP4_R1_INFO_PRODUCT_NAME               0x00
#define MIP4_R1_INFO_RESOLUTION_X               0x10
#define MIP4_R1_INFO_RESOLUTION_Y               0x12
#define MIP4_R1_INFO_NODE_NUM_X                 0x14
#define MIP4_R1_INFO_NODE_NUM_Y                 0x15
#define MIP4_R1_INFO_KEY_NUM                    0x16
#define MIP4_R1_INFO_PRESSURE_NUM               0x17
#define MIP4_R1_INFO_LENGTH_X                   0x18
#define MIP4_R1_INFO_LENGTH_Y                   0x1A
#define MIP4_R1_INFO_PPM_X                      0x1C
#define MIP4_R1_INFO_PPM_Y                      0x1D
#define MIP4_R1_INFO_VERSION_BOOT               0x20
#define MIP4_R1_INFO_VERSION_CORE               0x22
#define MIP4_R1_INFO_VERSION_APP                0x24
#define MIP4_R1_INFO_VERSION_PARAM              0x26
#define MIP4_R1_INFO_SECT_BOOT_START            0x30
#define MIP4_R1_INFO_SECT_BOOT_END              0x31
#define MIP4_R1_INFO_SECT_CORE_START            0x32
#define MIP4_R1_INFO_SECT_CORE_END              0x33
#define MIP4_R1_INFO_SECT_APP_START             0x34
#define MIP4_R1_INFO_SECT_APP_END               0x35
#define MIP4_R1_INFO_SECT_PARAM_START           0x36
#define MIP4_R1_INFO_SECT_PARAM_END             0x37
#define MIP4_R1_INFO_BUILD_DATE                 0x40
#define MIP4_R1_INFO_BUILD_TIME                 0x44
#define MIP4_R1_INFO_CHECKSUM_PRECALC           0x48
#define MIP4_R1_INFO_CHECKSUM_REALTIME          0x4A
#define MIP4_R1_INFO_PROTOCOL_NAME              0x50
#define MIP4_R1_INFO_PROTOCOL_VERSION           0x58
#define MIP4_R1_INFO_IC_ID                      0x70
#define MIP4_R1_INFO_IC_NAME                    0x71
#define MIP4_R1_INFO_IC_VENDOR_ID               0x75
#define MIP4_R1_INFO_IC_HW_CATEGORY             0x77
#define MIP4_R1_INFO_CONTACT_THD_SCR            0x78
#define MIP4_R1_INFO_CONTACT_THD_KEY            0x7A
#define MIP4_R1_INFO_PID                                0x7C
#define MIP4_R1_INFO_VID                                0x7E
#define MIP4_R1_INFO_SLAVE_ADDR                 0x80

#define MIP4_R0_EVENT                           0x02
#define MIP4_R1_EVENT_SUPPORTED_FUNC            0x00
#define MIP4_R1_EVENT_FORMAT                    0x04
#define MIP4_R1_EVENT_SIZE                      0x06
#define MIP4_R1_EVENT_PACKET_INFO               0x10
#define MIP4_R1_EVENT_PACKET_DATA               0x11

#define MIP4_R0_CTRL                            0x06
#define MIP4_R1_CTRL_READY_STATUS               0x00
#define MIP4_R1_CTRL_EVENT_READY                0x01
#define MIP4_R1_CTRL_MODE                       0x10
#define MIP4_R1_CTRL_EVENT_TRIGGER_TYPE         0x11
#define MIP4_R1_CTRL_RECALIBRATE                0x12
#define MIP4_R1_CTRL_POWER_STATE                0x13
#define MIP4_R1_CTRL_GESTURE_TYPE               0x14
#define MIP4_R1_CTRL_DISABLE_ESD_ALERT          0x18
#define MIP4_R1_CTRL_CHARGER_MODE               0x19
#define MIP4_R1_CTRL_HIGH_SENS_MODE             0x1A
#define MIP4_R1_CTRL_WINDOW_MODE                0x1B
#define MIP4_R1_CTRL_PALM_REJECTION             0x1C
#define MIP4_R1_CTRL_EDGE_CORRECTION            0x1D
#define MIP4_R1_CTRL_ENTER_GLOVE_MODE           0x1E
#define MIP4_R1_CTRL_I2C_ON_LPM                 0x1F
#define MIP4_R1_CTRL_GESTURE_DEBUG              0x20
#define MIP4_R1_CTRL_PALM_EVENT                 0x22
#define MIP4_R1_CTRL_PROXIMITY_SENSING          0x23

/* Value */
#define MIP4_BOOT_MODE_BOOT                     0x01
#define MIP4_BOOT_MODE_APP                      0x02

#define MIP4_BOOT_STATUS_BUSY                   0x05
#define MIP4_BOOT_STATUS_ERROR                  0x0E
#define MIP4_BOOT_STATUS_DONE                   0xA0

#define MIP4_BOOT_CMD_MASS_ERASE                0x15
#define MIP4_BOOT_CMD_PROGRAM                   0x54
#define MIP4_BOOT_CMD_ERASE                     0x8F
#define MIP4_BOOT_CMD_WRITE                     0xA5
#define MIP4_BOOT_CMD_READ                      0xC2

#define MIP4_EVENT_INPUT_TYPE_KEY               0
#define MIP4_EVENT_INPUT_TYPE_SCREEN            1
#define MIP4_EVENT_INPUT_TYPE_PROXIMITY         2

#define I2C_RETRY_COUNT                         3       /* 2~ */

#define MIP4_BUF_SIZE                           128
#define MIP4_MAX_FINGERS                        10
#define MIP4_MAX_KEYS                           4

#define MIP4_TOUCH_MAJOR_MIN                    0
#define MIP4_TOUCH_MAJOR_MAX                    255
#define MIP4_TOUCH_MINOR_MIN                    0
#define MIP4_TOUCH_MINOR_MAX                    255
#define MIP4_PRESSURE_MIN                       0
#define MIP4_PRESSURE_MAX                       255

#define MIP4_FW_NAME                    "melfas_mip4.fw"
#define MIP4_FW_UPDATE_DEBUG            0       /* 0 (default) or 1 */

struct mip4_fw_version {
        u16 boot;
        u16 core;
        u16 app;
        u16 param;
};

struct mip4_ts {
        struct i2c_client *client;
        struct input_dev *input;
        struct gpio_desc *gpio_ce;

        char phys[32];
        char product_name[16];
        u16 product_id;
        char ic_name[4];
        char fw_name[32];

        unsigned int max_x;
        unsigned int max_y;
        u8 node_x;
        u8 node_y;
        u8 node_key;
        unsigned int ppm_x;
        unsigned int ppm_y;

        struct mip4_fw_version fw_version;

        unsigned int event_size;
        unsigned int event_format;

        unsigned int key_num;
        unsigned short key_code[MIP4_MAX_KEYS];

        bool wake_irq_enabled;

        u8 buf[MIP4_BUF_SIZE];
};

static int mip4_i2c_xfer(struct mip4_ts *ts,
                         char *write_buf, unsigned int write_len,
                         char *read_buf, unsigned int read_len)
{
        struct i2c_msg msg[] = {
                {
                        .addr = ts->client->addr,
                        .flags = 0,
                        .buf = write_buf,
                        .len = write_len,
                }, {
                        .addr = ts->client->addr,
                        .flags = I2C_M_RD,
                        .buf = read_buf,
                        .len = read_len,
                },
        };
        int retry = I2C_RETRY_COUNT;
        int res;
        int error;

        do {
                res = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
                if (res == ARRAY_SIZE(msg))
                        return 0;

                error = res < 0 ? res : -EIO;
                dev_err(&ts->client->dev,
                        "%s - i2c_transfer failed: %d (%d)\n",
                        __func__, error, res);
        } while (--retry);

        return error;
}

static void mip4_parse_fw_version(const u8 *buf, struct mip4_fw_version *v)
{
        v->boot  = get_unaligned_le16(buf + 0);
        v->core  = get_unaligned_le16(buf + 2);
        v->app   = get_unaligned_le16(buf + 4);
        v->param = get_unaligned_le16(buf + 6);
}

/*
 * Read chip firmware version
 */
static int mip4_get_fw_version(struct mip4_ts *ts)
{
        u8 cmd[] = { MIP4_R0_INFO, MIP4_R1_INFO_VERSION_BOOT };
        u8 buf[sizeof(ts->fw_version)];
        int error;

        error = mip4_i2c_xfer(ts, cmd, sizeof(cmd), buf, sizeof(buf));
        if (error) {
                memset(&ts->fw_version, 0xff, sizeof(ts->fw_version));
                return error;
        }

        mip4_parse_fw_version(buf, &ts->fw_version);

        return 0;
}

/*
 * Fetch device characteristics
 */
static int mip4_query_device(struct mip4_ts *ts)
{
        union i2c_smbus_data dummy;
        int error;
        u8 cmd[2];
        u8 buf[14];

        /*
         * Make sure there is something at this address as we do not
         * consider subsequent failures as fatal.
         */
        if (i2c_smbus_xfer(ts->client->adapter, ts->client->addr,
                           0, I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) {
                dev_err(&ts->client->dev, "nothing at this address\n");
                return -ENXIO;
        }

        /* Product name */
        cmd[0] = MIP4_R0_INFO;
        cmd[1] = MIP4_R1_INFO_PRODUCT_NAME;
        error = mip4_i2c_xfer(ts, cmd, sizeof(cmd),
                              ts->product_name, sizeof(ts->product_name));
        if (error)
                dev_warn(&ts->client->dev,
                         "Failed to retrieve product name: %d\n", error);
        else
                dev_dbg(&ts->client->dev, "product name: %.*s\n",
                        (int)sizeof(ts->product_name), ts->product_name);

        /* Product ID */
        cmd[0] = MIP4_R0_INFO;
        cmd[1] = MIP4_R1_INFO_PID;
        error = mip4_i2c_xfer(ts, cmd, sizeof(cmd), buf, 2);
        if (error) {
                dev_warn(&ts->client->dev,
                         "Failed to retrieve product id: %d\n", error);
        } else {
                ts->product_id = get_unaligned_le16(&buf[0]);
                dev_dbg(&ts->client->dev, "product id: %04X\n", ts->product_id);
        }

        /* Firmware name */
        snprintf(ts->fw_name, sizeof(ts->fw_name),
                "melfas_mip4_%04X.fw", ts->product_id);
        dev_dbg(&ts->client->dev, "firmware name: %s\n", ts->fw_name);

        /* IC name */
        cmd[0] = MIP4_R0_INFO;
        cmd[1] = MIP4_R1_INFO_IC_NAME;
        error = mip4_i2c_xfer(ts, cmd, sizeof(cmd),
                              ts->ic_name, sizeof(ts->ic_name));
        if (error)
                dev_warn(&ts->client->dev,
                         "Failed to retrieve IC name: %d\n", error);
        else
                dev_dbg(&ts->client->dev, "IC name: %.*s\n",
                        (int)sizeof(ts->ic_name), ts->ic_name);

        /* Firmware version */
        error = mip4_get_fw_version(ts);
        if (error)
                dev_warn(&ts->client->dev,
                        "Failed to retrieve FW version: %d\n", error);
        else
                dev_dbg(&ts->client->dev, "F/W Version: %04X %04X %04X %04X\n",
                         ts->fw_version.boot, ts->fw_version.core,
                         ts->fw_version.app, ts->fw_version.param);

        /* Resolution */
        cmd[0] = MIP4_R0_INFO;
        cmd[1] = MIP4_R1_INFO_RESOLUTION_X;
        error = mip4_i2c_xfer(ts, cmd, sizeof(cmd), buf, 14);
        if (error) {
                dev_warn(&ts->client->dev,
                         "Failed to retrieve touchscreen parameters: %d\n",
                         error);
        } else {
                ts->max_x = get_unaligned_le16(&buf[0]);
                ts->max_y = get_unaligned_le16(&buf[2]);
                dev_dbg(&ts->client->dev, "max_x: %d, max_y: %d\n",
                        ts->max_x, ts->max_y);

                ts->node_x = buf[4];
                ts->node_y = buf[5];
                ts->node_key = buf[6];
                dev_dbg(&ts->client->dev,
                        "node_x: %d, node_y: %d, node_key: %d\n",
                        ts->node_x, ts->node_y, ts->node_key);

                ts->ppm_x = buf[12];
                ts->ppm_y = buf[13];
                dev_dbg(&ts->client->dev, "ppm_x: %d, ppm_y: %d\n",
                        ts->ppm_x, ts->ppm_y);

                /* Key ts */
                if (ts->node_key > 0)
                        ts->key_num = ts->node_key;
        }

        /* Protocol */
        cmd[0] = MIP4_R0_EVENT;
        cmd[1] = MIP4_R1_EVENT_SUPPORTED_FUNC;
        error = mip4_i2c_xfer(ts, cmd, sizeof(cmd), buf, 7);
        if (error) {
                dev_warn(&ts->client->dev,
                        "Failed to retrieve device type: %d\n", error);
                ts->event_format = 0xff;
        } else {
                ts->event_format = get_unaligned_le16(&buf[4]);
                ts->event_size = buf[6];
                dev_dbg(&ts->client->dev, "event_format: %d, event_size: %d\n",
                        ts->event_format, ts->event_size);

                if (ts->event_format == 2 || ts->event_format > 3)
                        dev_warn(&ts->client->dev,
                                 "Unknown event format %d\n", ts->event_format);
        }

        return 0;
}

static int mip4_power_on(struct mip4_ts *ts)
{
        if (ts->gpio_ce) {
                gpiod_set_value_cansleep(ts->gpio_ce, 1);

                /* Booting delay : 200~300ms */
                usleep_range(200 * 1000, 300 * 1000);
        }

        return 0;
}

static void mip4_power_off(struct mip4_ts *ts)
{
        if (ts->gpio_ce)
                gpiod_set_value_cansleep(ts->gpio_ce, 0);
}

/*
 * Clear touch input event status
 */
static void mip4_clear_input(struct mip4_ts *ts)
{
        int i;

        /* Screen */
        for (i = 0; i < MIP4_MAX_FINGERS; i++) {
                input_mt_slot(ts->input, i);
                input_mt_report_slot_inactive(ts->input);
        }

        /* Keys */
        for (i = 0; i < ts->key_num; i++)
                input_report_key(ts->input, ts->key_code[i], 0);

        input_sync(ts->input);
}

static int mip4_enable(struct mip4_ts *ts)
{
        int error;

        error = mip4_power_on(ts);
        if (error)
                return error;

        enable_irq(ts->client->irq);

        return 0;
}

static void mip4_disable(struct mip4_ts *ts)
{
        disable_irq(ts->client->irq);

        mip4_power_off(ts);

        mip4_clear_input(ts);
}

/*****************************************************************
 * Input handling
 *****************************************************************/

static void mip4_report_keys(struct mip4_ts *ts, u8 *packet)
{
        u8 key;
        bool down;

        switch (ts->event_format) {
        case 0:
        case 1:
                key = packet[0] & 0x0F;
                down = packet[0] & 0x80;
                break;

        case 3:
        default:
                key = packet[0] & 0x0F;
                down = packet[1] & 0x01;
                break;
        }

        /* Report key event */
        if (key >= 1 && key <= ts->key_num) {
                unsigned short keycode = ts->key_code[key - 1];

                dev_dbg(&ts->client->dev,
                        "Key - ID: %d, keycode: %d, state: %d\n",
                        key, keycode, down);

                input_event(ts->input, EV_MSC, MSC_SCAN, keycode);
                input_report_key(ts->input, keycode, down);

        } else {
                dev_err(&ts->client->dev, "Unknown key: %d\n", key);
        }
}

static void mip4_report_touch(struct mip4_ts *ts, u8 *packet)
{
        int id;
        bool __always_unused hover;
        bool palm;
        bool state;
        u16 x, y;
        u8 __always_unused pressure_stage = 0;
        u8 pressure;
        u8 __always_unused size;
        u8 touch_major;
        u8 touch_minor;

        switch (ts->event_format) {
        case 0:
        case 1:
                /* Touch only */
                state = packet[0] & BIT(7);
                hover = packet[0] & BIT(5);
                palm = packet[0] & BIT(4);
                id = (packet[0] & 0x0F) - 1;
                x = ((packet[1] & 0x0F) << 8) | packet[2];
                y = (((packet[1] >> 4) & 0x0F) << 8) |
                        packet[3];
                pressure = packet[4];
                size = packet[5];
                if (ts->event_format == 0) {
                        touch_major = packet[5];
                        touch_minor = packet[5];
                } else {
                        touch_major = packet[6];
                        touch_minor = packet[7];
                }
                break;

        case 3:
        default:
                /* Touch + Force(Pressure) */
                id = (packet[0] & 0x0F) - 1;
                hover = packet[1] & BIT(2);
                palm = packet[1] & BIT(1);
                state = packet[1] & BIT(0);
                x = ((packet[2] & 0x0F) << 8) | packet[3];
                y = (((packet[2] >> 4) & 0x0F) << 8) |
                        packet[4];
                size = packet[6];
                pressure_stage = (packet[7] & 0xF0) >> 4;
                pressure = ((packet[7] & 0x0F) << 8) |
                        packet[8];
                touch_major = packet[9];
                touch_minor = packet[10];
                break;
        }

        dev_dbg(&ts->client->dev,
                "Screen - Slot: %d State: %d X: %04d Y: %04d Z: %d\n",
                id, state, x, y, pressure);

        if (unlikely(id < 0 || id >= MIP4_MAX_FINGERS)) {
                dev_err(&ts->client->dev, "Screen - invalid slot ID: %d\n", id);
                goto out;
        }

        input_mt_slot(ts->input, id);
        if (input_mt_report_slot_state(ts->input,
                                       palm ? MT_TOOL_PALM : MT_TOOL_FINGER,
                                       state)) {
                input_report_abs(ts->input, ABS_MT_POSITION_X, x);
                input_report_abs(ts->input, ABS_MT_POSITION_Y, y);
                input_report_abs(ts->input, ABS_MT_PRESSURE, pressure);
                input_report_abs(ts->input, ABS_MT_TOUCH_MAJOR, touch_major);
                input_report_abs(ts->input, ABS_MT_TOUCH_MINOR, touch_minor);
        }

out:
        input_mt_sync_frame(ts->input);
}

static int mip4_handle_packet(struct mip4_ts *ts, u8 *packet)
{
        u8 type;

        switch (ts->event_format) {
        case 0:
        case 1:
                type = (packet[0] & 0x40) >> 6;
                break;

        case 3:
                type = (packet[0] & 0xF0) >> 4;
                break;

        default:
                /* Should not happen unless we have corrupted firmware */
                return -EINVAL;
        }

        dev_dbg(&ts->client->dev, "Type: %d\n", type);

        /* Report input event */
        switch (type) {
        case MIP4_EVENT_INPUT_TYPE_KEY:
                mip4_report_keys(ts, packet);
                break;

        case MIP4_EVENT_INPUT_TYPE_SCREEN:
                mip4_report_touch(ts, packet);
                break;

        default:
                dev_err(&ts->client->dev, "Unknown event type: %d\n", type);
                break;
        }

        return 0;
}

static irqreturn_t mip4_interrupt(int irq, void *dev_id)
{
        struct mip4_ts *ts = dev_id;
        struct i2c_client *client = ts->client;
        unsigned int i;
        int error;
        u8 cmd[2];
        u8 size;
        bool alert;

        /* Read packet info */
        cmd[0] = MIP4_R0_EVENT;
        cmd[1] = MIP4_R1_EVENT_PACKET_INFO;
        error = mip4_i2c_xfer(ts, cmd, sizeof(cmd), ts->buf, 1);
        if (error) {
                dev_err(&client->dev,
                        "Failed to read packet info: %d\n", error);
                goto out;
        }

        size = ts->buf[0] & 0x7F;
        alert = ts->buf[0] & BIT(7);
        dev_dbg(&client->dev, "packet size: %d, alert: %d\n", size, alert);

        /* Check size */
        if (!size) {
                dev_err(&client->dev, "Empty packet\n");
                goto out;
        }

        /* Read packet data */
        cmd[0] = MIP4_R0_EVENT;
        cmd[1] = MIP4_R1_EVENT_PACKET_DATA;
        error = mip4_i2c_xfer(ts, cmd, sizeof(cmd), ts->buf, size);
        if (error) {
                dev_err(&client->dev,
                        "Failed to read packet data: %d\n", error);
                goto out;
        }

        if (alert) {
                dev_dbg(&client->dev, "Alert: %d\n", ts->buf[0]);
        } else {
                for (i = 0; i < size; i += ts->event_size) {
                        error = mip4_handle_packet(ts, &ts->buf[i]);
                        if (error)
                                break;
                }

                input_sync(ts->input);
        }

out:
        return IRQ_HANDLED;
}

static int mip4_input_open(struct input_dev *dev)
{
        struct mip4_ts *ts = input_get_drvdata(dev);

        return mip4_enable(ts);
}

static void mip4_input_close(struct input_dev *dev)
{
        struct mip4_ts *ts = input_get_drvdata(dev);

        mip4_disable(ts);
}

/*****************************************************************
 * Firmware update
 *****************************************************************/

/* Firmware Info */
#define MIP4_BL_PAGE_SIZE               512     /* 512 */
#define MIP4_BL_PACKET_SIZE             512     /* 512, 256, 128, 64, ... */

/*
 * Firmware binary tail info
 */

struct mip4_bin_tail {
        u8 tail_mark[4];
        u8 chip_name[4];

        __le32 bin_start_addr;
        __le32 bin_length;

        __le16 ver_boot;
        __le16 ver_core;
        __le16 ver_app;
        __le16 ver_param;

        u8 boot_start;
        u8 boot_end;
        u8 core_start;
        u8 core_end;
        u8 app_start;
        u8 app_end;
        u8 param_start;
        u8 param_end;

        u8 checksum_type;
        u8 hw_category;

        __le16 param_id;
        __le32 param_length;
        __le32 build_date;
        __le32 build_time;

        __le32 reserved1;
        __le32 reserved2;
        __le16 reserved3;
        __le16 tail_size;
        __le32 crc;
} __packed;

#define MIP4_BIN_TAIL_MARK      "MBT\001"
#define MIP4_BIN_TAIL_SIZE      (sizeof(struct mip4_bin_tail))

/*
* Bootloader - Read status
*/
static int mip4_bl_read_status(struct mip4_ts *ts)
{
        u8 cmd[] = { MIP4_R0_BOOT, MIP4_R1_BOOT_STATUS };
        u8 result;
        struct i2c_msg msg[] = {
                {
                        .addr = ts->client->addr,
                        .flags = 0,
                        .buf = cmd,
                        .len = sizeof(cmd),
                }, {
                        .addr = ts->client->addr,
                        .flags = I2C_M_RD,
                        .buf = &result,
                        .len = sizeof(result),
                },
        };
        int ret;
        int error;
        int retry = 1000;

        do {
                ret = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
                if (ret != ARRAY_SIZE(msg)) {
                        error = ret < 0 ? ret : -EIO;
                        dev_err(&ts->client->dev,
                                "Failed to read bootloader status: %d\n",
                                error);
                        return error;
                }

                switch (result) {
                case MIP4_BOOT_STATUS_DONE:
                        dev_dbg(&ts->client->dev, "%s - done\n", __func__);
                        return 0;

                case MIP4_BOOT_STATUS_ERROR:
                        dev_err(&ts->client->dev, "Bootloader failure\n");
                        return -EIO;

                case MIP4_BOOT_STATUS_BUSY:
                        dev_dbg(&ts->client->dev, "%s - Busy\n", __func__);
                        error = -EBUSY;
                        break;

                default:
                        dev_err(&ts->client->dev,
                                "Unexpected bootloader status: %#02x\n",
                                result);
                        error = -EINVAL;
                        break;
                }

                usleep_range(1000, 2000);
        } while (--retry);

        return error;
}

/*
* Bootloader - Change mode
*/
static int mip4_bl_change_mode(struct mip4_ts *ts, u8 mode)
{
        u8 mode_chg_cmd[] = { MIP4_R0_BOOT, MIP4_R1_BOOT_MODE, mode };
        u8 mode_read_cmd[] = { MIP4_R0_BOOT, MIP4_R1_BOOT_MODE };
        u8 result;
        struct i2c_msg msg[] = {
                {
                        .addr = ts->client->addr,
                        .flags = 0,
                        .buf = mode_read_cmd,
                        .len = sizeof(mode_read_cmd),
                }, {
                        .addr = ts->client->addr,
                        .flags = I2C_M_RD,
                        .buf = &result,
                        .len = sizeof(result),
                },
        };
        int retry = 10;
        int ret;
        int error;

        do {
                /* Send mode change command */
                ret = i2c_master_send(ts->client,
                                      mode_chg_cmd, sizeof(mode_chg_cmd));
                if (ret != sizeof(mode_chg_cmd)) {
                        error = ret < 0 ? ret : -EIO;
                        dev_err(&ts->client->dev,
                                "Failed to send %d mode change: %d (%d)\n",
                                mode, error, ret);
                        return error;
                }

                dev_dbg(&ts->client->dev,
                        "Sent mode change request (mode: %d)\n", mode);

                /* Wait */
                msleep(1000);

                /* Verify target mode */
                ret = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
                if (ret != ARRAY_SIZE(msg)) {
                        error = ret < 0 ? ret : -EIO;
                        dev_err(&ts->client->dev,
                                "Failed to read device mode: %d\n", error);
                        return error;
                }

                dev_dbg(&ts->client->dev,
                        "Current device mode: %d, want: %d\n", result, mode);

                if (result == mode)
                        return 0;

        } while (--retry);

        return -EIO;
}

/*
 * Bootloader - Start bootloader mode
 */
static int mip4_bl_enter(struct mip4_ts *ts)
{
        return mip4_bl_change_mode(ts, MIP4_BOOT_MODE_BOOT);
}

/*
 * Bootloader - Exit bootloader mode
 */
static int mip4_bl_exit(struct mip4_ts *ts)
{
        return mip4_bl_change_mode(ts, MIP4_BOOT_MODE_APP);
}

static int mip4_bl_get_address(struct mip4_ts *ts, u16 *buf_addr)
{
        u8 cmd[] = { MIP4_R0_BOOT, MIP4_R1_BOOT_BUF_ADDR };
        u8 result[sizeof(u16)];
        struct i2c_msg msg[] = {
                {
                        .addr = ts->client->addr,
                        .flags = 0,
                        .buf = cmd,
                        .len = sizeof(cmd),
                }, {
                        .addr = ts->client->addr,
                        .flags = I2C_M_RD,
                        .buf = result,
                        .len = sizeof(result),
                },
        };
        int ret;
        int error;

        ret = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
        if (ret != ARRAY_SIZE(msg)) {
                error = ret < 0 ? ret : -EIO;
                dev_err(&ts->client->dev,
                        "Failed to retrieve bootloader buffer address: %d\n",
                        error);
                return error;
        }

        *buf_addr = get_unaligned_le16(result);
        dev_dbg(&ts->client->dev,
                "Bootloader buffer address %#04x\n", *buf_addr);

        return 0;
}

static int mip4_bl_program_page(struct mip4_ts *ts, int offset,
                                const u8 *data, int length, u16 buf_addr)
{
        u8 cmd[6];
        u8 *data_buf;
        u16 buf_offset;
        int ret;
        int error;

        dev_dbg(&ts->client->dev, "Writing page @%#06x (%d)\n",
                offset, length);

        if (length > MIP4_BL_PAGE_SIZE || length % MIP4_BL_PACKET_SIZE) {
                dev_err(&ts->client->dev,
                        "Invalid page length: %d\n", length);
                return -EINVAL;
        }

        data_buf = kmalloc(2 + MIP4_BL_PACKET_SIZE, GFP_KERNEL);
        if (!data_buf)
                return -ENOMEM;

        /* Addr */
        cmd[0] = MIP4_R0_BOOT;
        cmd[1] = MIP4_R1_BOOT_TARGET_ADDR;
        put_unaligned_le32(offset, &cmd[2]);
        ret = i2c_master_send(ts->client, cmd, 6);
        if (ret != 6) {
                error = ret < 0 ? ret : -EIO;
                dev_err(&ts->client->dev,
                        "Failed to send write page address: %d\n", error);
                goto out;
        }

        /* Size */
        cmd[0] = MIP4_R0_BOOT;
        cmd[1] = MIP4_R1_BOOT_SIZE;
        put_unaligned_le32(length, &cmd[2]);
        ret = i2c_master_send(ts->client, cmd, 6);
        if (ret != 6) {
                error = ret < 0 ? ret : -EIO;
                dev_err(&ts->client->dev,
                        "Failed to send write page size: %d\n", error);
                goto out;
        }

        /* Data */
        for (buf_offset = 0;
             buf_offset < length;
             buf_offset += MIP4_BL_PACKET_SIZE) {
                dev_dbg(&ts->client->dev,
                        "writing chunk at %#04x (size %d)\n",
                        buf_offset, MIP4_BL_PACKET_SIZE);
                put_unaligned_be16(buf_addr + buf_offset, data_buf);
                memcpy(&data_buf[2], &data[buf_offset], MIP4_BL_PACKET_SIZE);
                ret = i2c_master_send(ts->client,
                                      data_buf, 2 + MIP4_BL_PACKET_SIZE);
                if (ret != 2 + MIP4_BL_PACKET_SIZE) {
                        error = ret < 0 ? ret : -EIO;
                        dev_err(&ts->client->dev,
                                "Failed to read chunk at %#04x (size %d): %d\n",
                                buf_offset, MIP4_BL_PACKET_SIZE, error);
                        goto out;
                }
        }

        /* Command */
        cmd[0] = MIP4_R0_BOOT;
        cmd[1] = MIP4_R1_BOOT_CMD;
        cmd[2] = MIP4_BOOT_CMD_PROGRAM;
        ret = i2c_master_send(ts->client, cmd, 3);
        if (ret != 3) {
                error = ret < 0 ? ret : -EIO;
                dev_err(&ts->client->dev,
                        "Failed to send 'write' command: %d\n", error);
                goto out;
        }

        /* Status */
        error = mip4_bl_read_status(ts);

out:
        kfree(data_buf);
        return error ? error : 0;
}

static int mip4_bl_verify_page(struct mip4_ts *ts, int offset,
                               const u8 *data, int length, int buf_addr)
{
        u8 cmd[8];
        u8 *read_buf;
        int buf_offset;
        struct i2c_msg msg[] = {
                {
                        .addr = ts->client->addr,
                        .flags = 0,
                        .buf = cmd,
                        .len = 2,
                }, {
                        .addr = ts->client->addr,
                        .flags = I2C_M_RD,
                        .len = MIP4_BL_PACKET_SIZE,
                },
        };
        int ret;
        int error;

        dev_dbg(&ts->client->dev, "Validating page @%#06x (%d)\n",
                offset, length);

        /* Addr */
        cmd[0] = MIP4_R0_BOOT;
        cmd[1] = MIP4_R1_BOOT_TARGET_ADDR;
        put_unaligned_le32(offset, &cmd[2]);
        ret = i2c_master_send(ts->client, cmd, 6);
        if (ret != 6) {
                error = ret < 0 ? ret : -EIO;
                dev_err(&ts->client->dev,
                        "Failed to send read page address: %d\n", error);
                return error;
        }

        /* Size */
        cmd[0] = MIP4_R0_BOOT;
        cmd[1] = MIP4_R1_BOOT_SIZE;
        put_unaligned_le32(length, &cmd[2]);
        ret = i2c_master_send(ts->client, cmd, 6);
        if (ret != 6) {
                error = ret < 0 ? ret : -EIO;
                dev_err(&ts->client->dev,
                        "Failed to send read page size: %d\n", error);
                return error;
        }

        /* Command */
        cmd[0] = MIP4_R0_BOOT;
        cmd[1] = MIP4_R1_BOOT_CMD;
        cmd[2] = MIP4_BOOT_CMD_READ;
        ret = i2c_master_send(ts->client, cmd, 3);
        if (ret != 3) {
                error = ret < 0 ? ret : -EIO;
                dev_err(&ts->client->dev,
                        "Failed to send 'read' command: %d\n", error);
                return error;
        }

        /* Status */
        error = mip4_bl_read_status(ts);
        if (error)
                return error;

        /* Read */
        msg[1].buf = read_buf = kmalloc(MIP4_BL_PACKET_SIZE, GFP_KERNEL);
        if (!read_buf)
                return -ENOMEM;

        for (buf_offset = 0;
             buf_offset < length;
             buf_offset += MIP4_BL_PACKET_SIZE) {
                dev_dbg(&ts->client->dev,
                        "reading chunk at %#04x (size %d)\n",
                        buf_offset, MIP4_BL_PACKET_SIZE);
                put_unaligned_be16(buf_addr + buf_offset, cmd);
                ret = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
                if (ret != ARRAY_SIZE(msg)) {
                        error = ret < 0 ? ret : -EIO;
                        dev_err(&ts->client->dev,
                                "Failed to read chunk at %#04x (size %d): %d\n",
                                buf_offset, MIP4_BL_PACKET_SIZE, error);
                        break;
                }

                if (memcmp(&data[buf_offset], read_buf, MIP4_BL_PACKET_SIZE)) {
                        dev_err(&ts->client->dev,
                                "Failed to validate chunk at %#04x (size %d)\n",
                                buf_offset, MIP4_BL_PACKET_SIZE);
#if MIP4_FW_UPDATE_DEBUG
                        print_hex_dump(KERN_DEBUG,
                                       MIP4_DEVICE_NAME " F/W File: ",
                                       DUMP_PREFIX_OFFSET, 16, 1,
                                       data + offset, MIP4_BL_PACKET_SIZE,
                                       false);
                        print_hex_dump(KERN_DEBUG,
                                       MIP4_DEVICE_NAME " F/W Chip: ",
                                       DUMP_PREFIX_OFFSET, 16, 1,
                                       read_buf, MIP4_BL_PAGE_SIZE, false);
#endif
                        error = -EINVAL;
                        break;
                }
        }

        kfree(read_buf);
        return error ? error : 0;
}

/*
 * Flash chip firmware
 */
static int mip4_flash_fw(struct mip4_ts *ts,
                         const u8 *fw_data, u32 fw_size, u32 fw_offset)
{
        struct i2c_client *client = ts->client;
        int offset;
        u16 buf_addr;
        int error, error2;

        /* Enter bootloader mode */
        dev_dbg(&client->dev, "Entering bootloader mode\n");

        error = mip4_bl_enter(ts);
        if (error) {
                dev_err(&client->dev,
                        "Failed to enter bootloader mode: %d\n",
                        error);
                return error;
        }

        /* Read info */
        error = mip4_bl_get_address(ts, &buf_addr);
        if (error)
                goto exit_bl;

        /* Program & Verify */
        dev_dbg(&client->dev,
                "Program & Verify, page size: %d, packet size: %d\n",
                MIP4_BL_PAGE_SIZE, MIP4_BL_PACKET_SIZE);

        for (offset = fw_offset;
             offset < fw_offset + fw_size;
             offset += MIP4_BL_PAGE_SIZE) {
                /* Program */
                error = mip4_bl_program_page(ts, offset, fw_data + offset,
                                             MIP4_BL_PAGE_SIZE, buf_addr);
                if (error)
                        break;

                /* Verify */
                error = mip4_bl_verify_page(ts, offset, fw_data + offset,
                                            MIP4_BL_PAGE_SIZE, buf_addr);
                if (error)
                        break;
        }

exit_bl:
        /* Exit bootloader mode */
        dev_dbg(&client->dev, "Exiting bootloader mode\n");

        error2 = mip4_bl_exit(ts);
        if (error2) {
                dev_err(&client->dev,
                        "Failed to exit bootloader mode: %d\n", error2);
                if (!error)
                        error = error2;
        }

        /* Reset chip */
        mip4_power_off(ts);
        mip4_power_on(ts);

        mip4_query_device(ts);

        /* Refresh device parameters */
        input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, ts->max_x, 0, 0);
        input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, ts->max_y, 0, 0);
        input_set_abs_params(ts->input, ABS_X, 0, ts->max_x, 0, 0);
        input_set_abs_params(ts->input, ABS_Y, 0, ts->max_y, 0, 0);
        input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->ppm_x);
        input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->ppm_y);
        input_abs_set_res(ts->input, ABS_X, ts->ppm_x);
        input_abs_set_res(ts->input, ABS_Y, ts->ppm_y);

        return error ? error : 0;
}

static int mip4_parse_firmware(struct mip4_ts *ts, const struct firmware *fw,
                               u32 *fw_offset_start, u32 *fw_size,
                               const struct mip4_bin_tail **pfw_info)
{
        const struct mip4_bin_tail *fw_info;
        struct mip4_fw_version fw_version;
        u16 tail_size;

        if (fw->size < MIP4_BIN_TAIL_SIZE) {
                dev_err(&ts->client->dev,
                        "Invalid firmware, size mismatch (tail %zd vs %zd)\n",
                        MIP4_BIN_TAIL_SIZE, fw->size);
                return -EINVAL;
        }

        fw_info = (const void *)&fw->data[fw->size - MIP4_BIN_TAIL_SIZE];

#if MIP4_FW_UPDATE_DEBUG
        print_hex_dump(KERN_ERR, MIP4_DEVICE_NAME " Bin Info: ",
                       DUMP_PREFIX_OFFSET, 16, 1, *fw_info, tail_size, false);
#endif

        tail_size = get_unaligned_le16(&fw_info->tail_size);
        if (tail_size != MIP4_BIN_TAIL_SIZE) {
                dev_err(&ts->client->dev,
                        "wrong tail size: %d (expected %zd)\n",
                        tail_size, MIP4_BIN_TAIL_SIZE);
                return -EINVAL;
        }

        /* Check bin format */
        if (memcmp(fw_info->tail_mark, MIP4_BIN_TAIL_MARK,
                   sizeof(fw_info->tail_mark))) {
                dev_err(&ts->client->dev,
                        "unable to locate tail marker (%*ph vs %*ph)\n",
                        (int)sizeof(fw_info->tail_mark), fw_info->tail_mark,
                        (int)sizeof(fw_info->tail_mark), MIP4_BIN_TAIL_MARK);
                return -EINVAL;
        }

        *fw_offset_start = get_unaligned_le32(&fw_info->bin_start_addr);
        *fw_size = get_unaligned_le32(&fw_info->bin_length);

        dev_dbg(&ts->client->dev,
                "F/W Data offset: %#08x, size: %d\n",
                *fw_offset_start, *fw_size);

        if (*fw_size % MIP4_BL_PAGE_SIZE) {
                dev_err(&ts->client->dev,
                        "encoded fw length %d is not multiple of pages (%d)\n",
                        *fw_size, MIP4_BL_PAGE_SIZE);
                return -EINVAL;
        }

        if (fw->size != *fw_offset_start + *fw_size) {
                dev_err(&ts->client->dev,
                        "Wrong firmware size, expected %d bytes, got %zd\n",
                        *fw_offset_start + *fw_size, fw->size);
                return -EINVAL;
        }

        mip4_parse_fw_version((const u8 *)&fw_info->ver_boot, &fw_version);

        dev_dbg(&ts->client->dev,
                "F/W file version %04X %04X %04X %04X\n",
                fw_version.boot, fw_version.core,
                fw_version.app, fw_version.param);

        dev_dbg(&ts->client->dev, "F/W chip version: %04X %04X %04X %04X\n",
                 ts->fw_version.boot, ts->fw_version.core,
                 ts->fw_version.app, ts->fw_version.param);

        /* Check F/W type */
        if (fw_version.boot != 0xEEEE && fw_version.boot != 0xFFFF &&
            fw_version.core == 0xEEEE &&
            fw_version.app == 0xEEEE &&
            fw_version.param == 0xEEEE) {
                dev_dbg(&ts->client->dev, "F/W type: Bootloader\n");
        } else if (fw_version.boot == 0xEEEE &&
                   fw_version.core != 0xEEEE && fw_version.core != 0xFFFF &&
                   fw_version.app != 0xEEEE && fw_version.app != 0xFFFF &&
                   fw_version.param != 0xEEEE && fw_version.param != 0xFFFF) {
                dev_dbg(&ts->client->dev, "F/W type: Main\n");
        } else {
                dev_err(&ts->client->dev, "Wrong firmware type\n");
                return -EINVAL;
        }

        return 0;
}

static int mip4_execute_fw_update(struct mip4_ts *ts, const struct firmware *fw)
{
        const struct mip4_bin_tail *fw_info;
        u32 fw_start_offset;
        u32 fw_size;
        int retires = 3;
        int error;

        error = mip4_parse_firmware(ts, fw,
                                    &fw_start_offset, &fw_size, &fw_info);
        if (error)
                return error;

        if (input_device_enabled(ts->input)) {
                disable_irq(ts->client->irq);
        } else {
                error = mip4_power_on(ts);
                if (error)
                        return error;
        }

        /* Update firmware */
        do {
                error = mip4_flash_fw(ts, fw->data, fw_size, fw_start_offset);
                if (!error)
                        break;
        } while (--retires);

        if (error)
                dev_err(&ts->client->dev,
                        "Failed to flash firmware: %d\n", error);

        /* Enable IRQ */
        if (input_device_enabled(ts->input))
                enable_irq(ts->client->irq);
        else
                mip4_power_off(ts);

        return error ? error : 0;
}

static ssize_t mip4_sysfs_fw_update(struct device *dev,
                                    struct device_attribute *attr,
                                    const char *buf, size_t count)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct mip4_ts *ts = i2c_get_clientdata(client);
        const struct firmware *fw;
        int error;

        error = request_firmware(&fw, ts->fw_name, dev);
        if (error) {
                dev_err(&ts->client->dev,
                        "Failed to retrieve firmware %s: %d\n",
                        ts->fw_name, error);
                return error;
        }

        /*
         * Take input mutex to prevent racing with itself and also with
         * userspace opening and closing the device and also suspend/resume
         * transitions.
         */
        mutex_lock(&ts->input->mutex);

        error = mip4_execute_fw_update(ts, fw);

        mutex_unlock(&ts->input->mutex);

        release_firmware(fw);

        if (error) {
                dev_err(&ts->client->dev,
                        "Firmware update failed: %d\n", error);
                return error;
        }

        return count;
}

static DEVICE_ATTR(update_fw, S_IWUSR, NULL, mip4_sysfs_fw_update);

static ssize_t mip4_sysfs_read_fw_version(struct device *dev,
                                          struct device_attribute *attr,
                                          char *buf)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct mip4_ts *ts = i2c_get_clientdata(client);
        size_t count;

        /* Take lock to prevent racing with firmware update */
        mutex_lock(&ts->input->mutex);

        count = sysfs_emit(buf, "%04X %04X %04X %04X\n",
                           ts->fw_version.boot, ts->fw_version.core,
                           ts->fw_version.app, ts->fw_version.param);

        mutex_unlock(&ts->input->mutex);

        return count;
}

static DEVICE_ATTR(fw_version, S_IRUGO, mip4_sysfs_read_fw_version, NULL);

static ssize_t mip4_sysfs_read_hw_version(struct device *dev,
                                          struct device_attribute *attr,
                                          char *buf)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct mip4_ts *ts = i2c_get_clientdata(client);
        size_t count;

        /* Take lock to prevent racing with firmware update */
        mutex_lock(&ts->input->mutex);

        /*
         * product_name shows the name or version of the hardware
         * paired with current firmware in the chip.
         */
        count = sysfs_emit(buf, "%.*s\n",
                           (int)sizeof(ts->product_name), ts->product_name);

        mutex_unlock(&ts->input->mutex);

        return count;
}

static DEVICE_ATTR(hw_version, S_IRUGO, mip4_sysfs_read_hw_version, NULL);

static ssize_t mip4_sysfs_read_product_id(struct device *dev,
                                          struct device_attribute *attr,
                                          char *buf)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct mip4_ts *ts = i2c_get_clientdata(client);
        size_t count;

        mutex_lock(&ts->input->mutex);

        count = sysfs_emit(buf, "%04X\n", ts->product_id);

        mutex_unlock(&ts->input->mutex);

        return count;
}

static DEVICE_ATTR(product_id, S_IRUGO, mip4_sysfs_read_product_id, NULL);

static ssize_t mip4_sysfs_read_ic_name(struct device *dev,
                                          struct device_attribute *attr,
                                          char *buf)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct mip4_ts *ts = i2c_get_clientdata(client);
        size_t count;

        mutex_lock(&ts->input->mutex);

        count = sysfs_emit(buf, "%.*s\n",
                           (int)sizeof(ts->ic_name), ts->ic_name);

        mutex_unlock(&ts->input->mutex);

        return count;
}

static DEVICE_ATTR(ic_name, S_IRUGO, mip4_sysfs_read_ic_name, NULL);

static struct attribute *mip4_attrs[] = {
        &dev_attr_fw_version.attr,
        &dev_attr_hw_version.attr,
        &dev_attr_product_id.attr,
        &dev_attr_ic_name.attr,
        &dev_attr_update_fw.attr,
        NULL,
};
ATTRIBUTE_GROUPS(mip4);

static int mip4_probe(struct i2c_client *client)
{
        struct mip4_ts *ts;
        struct input_dev *input;
        int error;

        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
                dev_err(&client->dev, "Not supported I2C adapter\n");
                return -ENXIO;
        }

        ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
        if (!ts)
                return -ENOMEM;

        input = devm_input_allocate_device(&client->dev);
        if (!input)
                return -ENOMEM;

        ts->client = client;
        ts->input = input;

        snprintf(ts->phys, sizeof(ts->phys),
                 "%s/input0", dev_name(&client->dev));

        ts->gpio_ce = devm_gpiod_get_optional(&client->dev,
                                              "ce", GPIOD_OUT_LOW);
        if (IS_ERR(ts->gpio_ce))
                return dev_err_probe(&client->dev, PTR_ERR(ts->gpio_ce), "Failed to get gpio\n");

        error = mip4_power_on(ts);
        if (error)
                return error;
        error = mip4_query_device(ts);
        mip4_power_off(ts);
        if (error)
                return error;

        input->name = "MELFAS MIP4 Touchscreen";
        input->phys = ts->phys;

        input->id.bustype = BUS_I2C;
        input->id.vendor = 0x13c5;
        input->id.product = ts->product_id;

        input->open = mip4_input_open;
        input->close = mip4_input_close;

        input_set_drvdata(input, ts);

        input->keycode = ts->key_code;
        input->keycodesize = sizeof(*ts->key_code);
        input->keycodemax = ts->key_num;

        input_set_abs_params(input, ABS_MT_TOOL_TYPE, 0, MT_TOOL_PALM, 0, 0);
        input_set_abs_params(input, ABS_MT_POSITION_X, 0, ts->max_x, 0, 0);
        input_set_abs_params(input, ABS_MT_POSITION_Y, 0, ts->max_y, 0, 0);
        input_set_abs_params(input, ABS_MT_PRESSURE,
                             MIP4_PRESSURE_MIN, MIP4_PRESSURE_MAX, 0, 0);
        input_set_abs_params(input, ABS_MT_TOUCH_MAJOR,
                             MIP4_TOUCH_MAJOR_MIN, MIP4_TOUCH_MAJOR_MAX, 0, 0);
        input_set_abs_params(input, ABS_MT_TOUCH_MINOR,
                             MIP4_TOUCH_MINOR_MIN, MIP4_TOUCH_MINOR_MAX, 0, 0);
        input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->ppm_x);
        input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->ppm_y);

        error = input_mt_init_slots(input, MIP4_MAX_FINGERS, INPUT_MT_DIRECT);
        if (error)
                return error;

        i2c_set_clientdata(client, ts);

        error = devm_request_threaded_irq(&client->dev, client->irq,
                                          NULL, mip4_interrupt,
                                          IRQF_ONESHOT | IRQF_NO_AUTOEN,
                                          MIP4_DEVICE_NAME, ts);
        if (error) {
                dev_err(&client->dev,
                        "Failed to request interrupt %d: %d\n",
                        client->irq, error);
                return error;
        }

        error = input_register_device(input);
        if (error) {
                dev_err(&client->dev,
                        "Failed to register input device: %d\n", error);
                return error;
        }

        return 0;
}

static int mip4_suspend(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct mip4_ts *ts = i2c_get_clientdata(client);
        struct input_dev *input = ts->input;

        mutex_lock(&input->mutex);

        if (device_may_wakeup(dev))
                ts->wake_irq_enabled = enable_irq_wake(client->irq) == 0;
        else if (input_device_enabled(input))
                mip4_disable(ts);

        mutex_unlock(&input->mutex);

        return 0;
}

static int mip4_resume(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct mip4_ts *ts = i2c_get_clientdata(client);
        struct input_dev *input = ts->input;

        mutex_lock(&input->mutex);

        if (ts->wake_irq_enabled)
                disable_irq_wake(client->irq);
        else if (input_device_enabled(input))
                mip4_enable(ts);

        mutex_unlock(&input->mutex);

        return 0;
}

static DEFINE_SIMPLE_DEV_PM_OPS(mip4_pm_ops, mip4_suspend, mip4_resume);

#ifdef CONFIG_OF
static const struct of_device_id mip4_of_match[] = {
        { .compatible = "melfas,mip4_ts", },
        { },
};
MODULE_DEVICE_TABLE(of, mip4_of_match);
#endif

#ifdef CONFIG_ACPI
static const struct acpi_device_id mip4_acpi_match[] = {
        { "MLFS0000", 0},
        { },
};
MODULE_DEVICE_TABLE(acpi, mip4_acpi_match);
#endif

static const struct i2c_device_id mip4_i2c_ids[] = {
        { MIP4_DEVICE_NAME },
        { }
};
MODULE_DEVICE_TABLE(i2c, mip4_i2c_ids);

static struct i2c_driver mip4_driver = {
        .id_table = mip4_i2c_ids,
        .probe = mip4_probe,
        .driver = {
                .name = MIP4_DEVICE_NAME,
                .dev_groups = mip4_groups,
                .of_match_table = of_match_ptr(mip4_of_match),
                .acpi_match_table = ACPI_PTR(mip4_acpi_match),
                .pm = pm_sleep_ptr(&mip4_pm_ops),
        },
};
module_i2c_driver(mip4_driver);

MODULE_DESCRIPTION("MELFAS MIP4 Touchscreen");
MODULE_AUTHOR("Sangwon Jee <jeesw@melfas.com>");
MODULE_LICENSE("GPL");