root/drivers/input/touchscreen/hideep.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2012-2017 Hideep, Inc.
 */

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

#define HIDEEP_TS_NAME                  "HiDeep Touchscreen"
#define HIDEEP_I2C_NAME                 "hideep_ts"

#define HIDEEP_MT_MAX                   10
#define HIDEEP_KEY_MAX                  3

/* count(2) + touch data(100) + key data(6) */
#define HIDEEP_MAX_EVENT                108UL

#define HIDEEP_TOUCH_EVENT_INDEX        2
#define HIDEEP_KEY_EVENT_INDEX          102

/* Touch & key event */
#define HIDEEP_EVENT_ADDR               0x240

/* command list */
#define HIDEEP_WORK_MODE                0x081e
#define HIDEEP_RESET_CMD                0x9800

/* event bit */
#define HIDEEP_MT_RELEASED              BIT(4)
#define HIDEEP_KEY_PRESSED              BIT(7)
#define HIDEEP_KEY_FIRST_PRESSED        BIT(8)
#define HIDEEP_KEY_PRESSED_MASK         (HIDEEP_KEY_PRESSED | \
                                         HIDEEP_KEY_FIRST_PRESSED)

#define HIDEEP_KEY_IDX_MASK             0x0f

/* For NVM */
#define HIDEEP_YRAM_BASE                0x40000000
#define HIDEEP_PERIPHERAL_BASE          0x50000000
#define HIDEEP_ESI_BASE                 (HIDEEP_PERIPHERAL_BASE + 0x00000000)
#define HIDEEP_FLASH_BASE               (HIDEEP_PERIPHERAL_BASE + 0x01000000)
#define HIDEEP_SYSCON_BASE              (HIDEEP_PERIPHERAL_BASE + 0x02000000)

#define HIDEEP_SYSCON_MOD_CON           (HIDEEP_SYSCON_BASE + 0x0000)
#define HIDEEP_SYSCON_SPC_CON           (HIDEEP_SYSCON_BASE + 0x0004)
#define HIDEEP_SYSCON_CLK_CON           (HIDEEP_SYSCON_BASE + 0x0008)
#define HIDEEP_SYSCON_CLK_ENA           (HIDEEP_SYSCON_BASE + 0x000C)
#define HIDEEP_SYSCON_RST_CON           (HIDEEP_SYSCON_BASE + 0x0010)
#define HIDEEP_SYSCON_WDT_CON           (HIDEEP_SYSCON_BASE + 0x0014)
#define HIDEEP_SYSCON_WDT_CNT           (HIDEEP_SYSCON_BASE + 0x0018)
#define HIDEEP_SYSCON_PWR_CON           (HIDEEP_SYSCON_BASE + 0x0020)
#define HIDEEP_SYSCON_PGM_ID            (HIDEEP_SYSCON_BASE + 0x00F4)

#define HIDEEP_FLASH_CON                (HIDEEP_FLASH_BASE + 0x0000)
#define HIDEEP_FLASH_STA                (HIDEEP_FLASH_BASE + 0x0004)
#define HIDEEP_FLASH_CFG                (HIDEEP_FLASH_BASE + 0x0008)
#define HIDEEP_FLASH_TIM                (HIDEEP_FLASH_BASE + 0x000C)
#define HIDEEP_FLASH_CACHE_CFG          (HIDEEP_FLASH_BASE + 0x0010)
#define HIDEEP_FLASH_PIO_SIG            (HIDEEP_FLASH_BASE + 0x400000)

#define HIDEEP_ESI_TX_INVALID           (HIDEEP_ESI_BASE + 0x0008)

#define HIDEEP_PERASE                   0x00040000
#define HIDEEP_WRONLY                   0x00100000

#define HIDEEP_NVM_MASK_OFS             0x0000000C
#define HIDEEP_NVM_DEFAULT_PAGE         0
#define HIDEEP_NVM_SFR_WPAGE            1
#define HIDEEP_NVM_SFR_RPAGE            2

#define HIDEEP_PIO_SIG                  0x00400000
#define HIDEEP_PROT_MODE                0x03400000

#define HIDEEP_NVM_PAGE_SIZE            128

#define HIDEEP_DWZ_INFO                 0x000002C0

struct hideep_event {
        __le16 x;
        __le16 y;
        __le16 z;
        u8 w;
        u8 flag;
        u8 type;
        u8 index;
};

struct dwz_info {
        __be32 code_start;
        u8 code_crc[12];

        __be32 c_code_start;
        __be16 gen_ver;
        __be16 c_code_len;

        __be32 vr_start;
        __be16 rsv0;
        __be16 vr_len;

        __be32 ft_start;
        __be16 vr_version;
        __be16 ft_len;

        __be16 core_ver;
        __be16 boot_ver;

        __be16 release_ver;
        __be16 custom_ver;

        u8 factory_id;
        u8 panel_type;
        u8 model_name[6];

        __be16 extra_option;
        __be16 product_code;

        __be16 vendor_id;
        __be16 product_id;
};

struct pgm_packet {
        struct {
                u8 unused[3];
                u8 len;
                __be32 addr;
        } header;
        __be32 payload[HIDEEP_NVM_PAGE_SIZE / sizeof(__be32)];
};

#define HIDEEP_XFER_BUF_SIZE    sizeof(struct pgm_packet)

struct hideep_ts {
        struct i2c_client *client;
        struct input_dev *input_dev;
        struct regmap *reg;

        struct touchscreen_properties prop;

        struct gpio_desc *reset_gpio;

        struct regulator *vcc_vdd;
        struct regulator *vcc_vid;

        struct mutex dev_mutex;

        u32 tch_count;
        u32 lpm_count;

        /*
         * Data buffer to read packet from the device (contacts and key
         * states). We align it on double-word boundary to keep word-sized
         * fields in contact data and double-word-sized fields in program
         * packet aligned.
         */
        u8 xfer_buf[HIDEEP_XFER_BUF_SIZE] __aligned(4);

        int key_num;
        u32 key_codes[HIDEEP_KEY_MAX];

        struct dwz_info dwz_info;

        unsigned int fw_size;
        u32 nvm_mask;
};

static int hideep_pgm_w_mem(struct hideep_ts *ts, u32 addr,
                            const __be32 *data, size_t count)
{
        struct pgm_packet *packet = (void *)ts->xfer_buf;
        size_t len = count * sizeof(*data);
        struct i2c_msg msg = {
                .addr   = ts->client->addr,
                .len    = len + sizeof(packet->header.len) +
                                sizeof(packet->header.addr),
                .buf    = &packet->header.len,
        };
        int ret;

        if (len > HIDEEP_NVM_PAGE_SIZE)
                return -EINVAL;

        packet->header.len = 0x80 | (count - 1);
        packet->header.addr = cpu_to_be32(addr);
        memcpy(packet->payload, data, len);

        ret = i2c_transfer(ts->client->adapter, &msg, 1);
        if (ret != 1)
                return ret < 0 ? ret : -EIO;

        return 0;
}

static int hideep_pgm_r_mem(struct hideep_ts *ts, u32 addr,
                            __be32 *data, size_t count)
{
        struct pgm_packet *packet = (void *)ts->xfer_buf;
        size_t len = count * sizeof(*data);
        struct i2c_msg msg[] = {
                {
                        .addr   = ts->client->addr,
                        .len    = sizeof(packet->header.len) +
                                        sizeof(packet->header.addr),
                        .buf    = &packet->header.len,
                },
                {
                        .addr   = ts->client->addr,
                        .flags  = I2C_M_RD,
                        .len    = len,
                        .buf    = (u8 *)data,
                },
        };
        int ret;

        if (len > HIDEEP_NVM_PAGE_SIZE)
                return -EINVAL;

        packet->header.len = count - 1;
        packet->header.addr = cpu_to_be32(addr);

        ret = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg));
        if (ret != ARRAY_SIZE(msg))
                return ret < 0 ? ret : -EIO;

        return 0;
}

static int hideep_pgm_r_reg(struct hideep_ts *ts, u32 addr, u32 *val)
{
        __be32 data;
        int error;

        error = hideep_pgm_r_mem(ts, addr, &data, 1);
        if (error) {
                dev_err(&ts->client->dev,
                        "read of register %#08x failed: %d\n",
                        addr, error);
                return error;
        }

        *val = be32_to_cpu(data);
        return 0;
}

static int hideep_pgm_w_reg(struct hideep_ts *ts, u32 addr, u32 val)
{
        __be32 data = cpu_to_be32(val);
        int error;

        error = hideep_pgm_w_mem(ts, addr, &data, 1);
        if (error) {
                dev_err(&ts->client->dev,
                        "write to register %#08x (%#08x) failed: %d\n",
                        addr, val, error);
                return error;
        }

        return 0;
}

#define SW_RESET_IN_PGM(clk)                                    \
{                                                               \
        __be32 data = cpu_to_be32(0x01);                        \
        hideep_pgm_w_reg(ts, HIDEEP_SYSCON_WDT_CNT, (clk));     \
        hideep_pgm_w_reg(ts, HIDEEP_SYSCON_WDT_CON, 0x03);      \
        /*                                                      \
         * The first write may already cause a reset, use a raw \
         * write for the second write to avoid error logging.   \
         */                                                     \
        hideep_pgm_w_mem(ts, HIDEEP_SYSCON_WDT_CON, &data, 1);  \
}

#define SET_FLASH_PIO(ce)                                       \
        hideep_pgm_w_reg(ts, HIDEEP_FLASH_CON,                  \
                         0x01 | ((ce) << 1))

#define SET_PIO_SIG(x, y)                                       \
        hideep_pgm_w_reg(ts, HIDEEP_FLASH_PIO_SIG + (x), (y))

#define SET_FLASH_HWCONTROL()                                   \
        hideep_pgm_w_reg(ts, HIDEEP_FLASH_CON, 0x00)

#define NVM_W_SFR(x, y)                                         \
{                                                               \
        SET_FLASH_PIO(1);                                       \
        SET_PIO_SIG(x, y);                                      \
        SET_FLASH_PIO(0);                                       \
}

static void hideep_pgm_set(struct hideep_ts *ts)
{
        hideep_pgm_w_reg(ts, HIDEEP_SYSCON_WDT_CON, 0x00);
        hideep_pgm_w_reg(ts, HIDEEP_SYSCON_SPC_CON, 0x00);
        hideep_pgm_w_reg(ts, HIDEEP_SYSCON_CLK_ENA, 0xFF);
        hideep_pgm_w_reg(ts, HIDEEP_SYSCON_CLK_CON, 0x01);
        hideep_pgm_w_reg(ts, HIDEEP_SYSCON_PWR_CON, 0x01);
        hideep_pgm_w_reg(ts, HIDEEP_FLASH_TIM, 0x03);
        hideep_pgm_w_reg(ts, HIDEEP_FLASH_CACHE_CFG, 0x00);
}

static int hideep_pgm_get_pattern(struct hideep_ts *ts, u32 *pattern)
{
        u16 p1 = 0xAF39;
        u16 p2 = 0xDF9D;
        int error;

        error = regmap_bulk_write(ts->reg, p1, &p2, 1);
        if (error) {
                dev_err(&ts->client->dev,
                        "%s: regmap_bulk_write() failed with %d\n",
                        __func__, error);
                return error;
        }

        usleep_range(1000, 1100);

        /* flush invalid Tx load register */
        error = hideep_pgm_w_reg(ts, HIDEEP_ESI_TX_INVALID, 0x01);
        if (error)
                return error;

        error = hideep_pgm_r_reg(ts, HIDEEP_SYSCON_PGM_ID, pattern);
        if (error)
                return error;

        return 0;
}

static int hideep_enter_pgm(struct hideep_ts *ts)
{
        int retry_count = 10;
        u32 pattern;
        int error;

        while (retry_count--) {
                error = hideep_pgm_get_pattern(ts, &pattern);
                if (error) {
                        dev_err(&ts->client->dev,
                                "hideep_pgm_get_pattern failed: %d\n", error);
                } else if (pattern != 0x39AF9DDF) {
                        dev_err(&ts->client->dev, "%s: bad pattern: %#08x\n",
                                __func__, pattern);
                } else {
                        dev_dbg(&ts->client->dev, "found magic code");

                        hideep_pgm_set(ts);
                        usleep_range(1000, 1100);

                        return 0;
                }
        }

        dev_err(&ts->client->dev, "failed to  enter pgm mode\n");
        SW_RESET_IN_PGM(1000);
        return -EIO;
}

static int hideep_nvm_unlock(struct hideep_ts *ts)
{
        u32 unmask_code;
        int error;

        hideep_pgm_w_reg(ts, HIDEEP_FLASH_CFG, HIDEEP_NVM_SFR_RPAGE);
        error = hideep_pgm_r_reg(ts, 0x0000000C, &unmask_code);
        hideep_pgm_w_reg(ts, HIDEEP_FLASH_CFG, HIDEEP_NVM_DEFAULT_PAGE);
        if (error)
                return error;

        /* make it unprotected code */
        unmask_code &= ~HIDEEP_PROT_MODE;

        /* compare unmask code */
        if (unmask_code != ts->nvm_mask)
                dev_warn(&ts->client->dev,
                         "read mask code different %#08x vs %#08x",
                         unmask_code, ts->nvm_mask);

        hideep_pgm_w_reg(ts, HIDEEP_FLASH_CFG, HIDEEP_NVM_SFR_WPAGE);
        SET_FLASH_PIO(0);

        NVM_W_SFR(HIDEEP_NVM_MASK_OFS, ts->nvm_mask);
        SET_FLASH_HWCONTROL();
        hideep_pgm_w_reg(ts, HIDEEP_FLASH_CFG, HIDEEP_NVM_DEFAULT_PAGE);

        return 0;
}

static int hideep_check_status(struct hideep_ts *ts)
{
        int time_out = 100;
        int status;
        int error;

        while (time_out--) {
                error = hideep_pgm_r_reg(ts, HIDEEP_FLASH_STA, &status);
                if (!error && status)
                        return 0;

                usleep_range(1000, 1100);
        }

        return -ETIMEDOUT;
}

static int hideep_program_page(struct hideep_ts *ts, u32 addr,
                               const __be32 *ucode, size_t xfer_count)
{
        u32 val;
        int error;

        error = hideep_check_status(ts);
        if (error)
                return -EBUSY;

        addr &= ~(HIDEEP_NVM_PAGE_SIZE - 1);

        SET_FLASH_PIO(0);
        SET_FLASH_PIO(1);

        /* erase page */
        SET_PIO_SIG(HIDEEP_PERASE | addr, 0xFFFFFFFF);

        SET_FLASH_PIO(0);

        error = hideep_check_status(ts);
        if (error)
                return -EBUSY;

        /* write page */
        SET_FLASH_PIO(1);

        val = be32_to_cpu(ucode[0]);
        SET_PIO_SIG(HIDEEP_WRONLY | addr, val);

        hideep_pgm_w_mem(ts, HIDEEP_FLASH_PIO_SIG | HIDEEP_WRONLY,
                         ucode, xfer_count);

        val = be32_to_cpu(ucode[xfer_count - 1]);
        SET_PIO_SIG(124, val);

        SET_FLASH_PIO(0);

        usleep_range(1000, 1100);

        error = hideep_check_status(ts);
        if (error)
                return -EBUSY;

        SET_FLASH_HWCONTROL();

        return 0;
}

static int hideep_program_nvm(struct hideep_ts *ts,
                              const __be32 *ucode, size_t ucode_len)
{
        struct pgm_packet *packet_r = (void *)ts->xfer_buf;
        __be32 *current_ucode = packet_r->payload;
        size_t xfer_len;
        size_t xfer_count;
        u32 addr = 0;
        int error;

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

        while (ucode_len > 0) {
                xfer_len = min_t(size_t, ucode_len, HIDEEP_NVM_PAGE_SIZE);
                xfer_count = xfer_len / sizeof(*ucode);

                error = hideep_pgm_r_mem(ts, 0x00000000 + addr,
                                         current_ucode, xfer_count);
                if (error) {
                        dev_err(&ts->client->dev,
                                "%s: failed to read page at offset %#08x: %d\n",
                                __func__, addr, error);
                        return error;
                }

                /* See if the page needs updating */
                if (memcmp(ucode, current_ucode, xfer_len)) {
                        error = hideep_program_page(ts, addr,
                                                    ucode, xfer_count);
                        if (error) {
                                dev_err(&ts->client->dev,
                                        "%s: iwrite failure @%#08x: %d\n",
                                        __func__, addr, error);
                                return error;
                        }

                        usleep_range(1000, 1100);
                }

                ucode += xfer_count;
                addr += xfer_len;
                ucode_len -= xfer_len;
        }

        return 0;
}

static int hideep_verify_nvm(struct hideep_ts *ts,
                             const __be32 *ucode, size_t ucode_len)
{
        struct pgm_packet *packet_r = (void *)ts->xfer_buf;
        __be32 *current_ucode = packet_r->payload;
        size_t xfer_len;
        size_t xfer_count;
        u32 addr = 0;
        int i;
        int error;

        while (ucode_len > 0) {
                xfer_len = min_t(size_t, ucode_len, HIDEEP_NVM_PAGE_SIZE);
                xfer_count = xfer_len / sizeof(*ucode);

                error = hideep_pgm_r_mem(ts, 0x00000000 + addr,
                                         current_ucode, xfer_count);
                if (error) {
                        dev_err(&ts->client->dev,
                                "%s: failed to read page at offset %#08x: %d\n",
                                __func__, addr, error);
                        return error;
                }

                if (memcmp(ucode, current_ucode, xfer_len)) {
                        const u8 *ucode_bytes = (const u8 *)ucode;
                        const u8 *current_bytes = (const u8 *)current_ucode;

                        for (i = 0; i < xfer_len; i++)
                                if (ucode_bytes[i] != current_bytes[i])
                                        dev_err(&ts->client->dev,
                                                "%s: mismatch @%#08x: (%#02x vs %#02x)\n",
                                                __func__, addr + i,
                                                ucode_bytes[i],
                                                current_bytes[i]);

                        return -EIO;
                }

                ucode += xfer_count;
                addr += xfer_len;
                ucode_len -= xfer_len;
        }

        return 0;
}

static int hideep_load_dwz(struct hideep_ts *ts)
{
        u16 product_code;
        int error;

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

        msleep(50);

        error = hideep_pgm_r_mem(ts, HIDEEP_DWZ_INFO,
                                 (void *)&ts->dwz_info,
                                 sizeof(ts->dwz_info) / sizeof(__be32));

        SW_RESET_IN_PGM(10);
        msleep(50);

        if (error) {
                dev_err(&ts->client->dev,
                        "failed to fetch DWZ data: %d\n", error);
                return error;
        }

        product_code = be16_to_cpu(ts->dwz_info.product_code);

        switch (product_code & 0xF0) {
        case 0x40:
                dev_dbg(&ts->client->dev, "used crimson IC");
                ts->fw_size = 1024 * 48;
                ts->nvm_mask = 0x00310000;
                break;
        case 0x60:
                dev_dbg(&ts->client->dev, "used lime IC");
                ts->fw_size = 1024 * 64;
                ts->nvm_mask = 0x0030027B;
                break;
        default:
                dev_err(&ts->client->dev, "product code is wrong: %#04x",
                        product_code);
                return -EINVAL;
        }

        dev_dbg(&ts->client->dev, "firmware release version: %#04x",
                be16_to_cpu(ts->dwz_info.release_ver));

        return 0;
}

static int hideep_flash_firmware(struct hideep_ts *ts,
                                 const __be32 *ucode, size_t ucode_len)
{
        int retry_cnt = 3;
        int error;

        while (retry_cnt--) {
                error = hideep_program_nvm(ts, ucode, ucode_len);
                if (!error) {
                        error = hideep_verify_nvm(ts, ucode, ucode_len);
                        if (!error)
                                return 0;
                }
        }

        return error;
}

static int hideep_update_firmware(struct hideep_ts *ts,
                                  const __be32 *ucode, size_t ucode_len)
{
        int error, error2;

        dev_dbg(&ts->client->dev, "starting firmware update");

        /* enter program mode */
        error = hideep_enter_pgm(ts);
        if (error)
                return error;

        error = hideep_flash_firmware(ts, ucode, ucode_len);
        if (error)
                dev_err(&ts->client->dev,
                        "firmware update failed: %d\n", error);
        else
                dev_dbg(&ts->client->dev, "firmware updated successfully\n");

        SW_RESET_IN_PGM(1000);

        error2 = hideep_load_dwz(ts);
        if (error2)
                dev_err(&ts->client->dev,
                        "failed to load dwz after firmware update: %d\n",
                        error2);

        return error ?: error2;
}

static int hideep_power_on(struct hideep_ts *ts)
{
        int error = 0;

        error = regulator_enable(ts->vcc_vdd);
        if (error)
                dev_err(&ts->client->dev,
                        "failed to enable 'vdd' regulator: %d", error);

        usleep_range(999, 1000);

        error = regulator_enable(ts->vcc_vid);
        if (error)
                dev_err(&ts->client->dev,
                        "failed to enable 'vcc_vid' regulator: %d",
                        error);

        msleep(30);

        if (ts->reset_gpio) {
                gpiod_set_value_cansleep(ts->reset_gpio, 0);
        } else {
                error = regmap_write(ts->reg, HIDEEP_RESET_CMD, 0x01);
                if (error)
                        dev_err(&ts->client->dev,
                                "failed to send 'reset' command: %d\n", error);
        }

        msleep(50);

        return error;
}

static void hideep_power_off(void *data)
{
        struct hideep_ts *ts = data;

        if (ts->reset_gpio)
                gpiod_set_value(ts->reset_gpio, 1);

        regulator_disable(ts->vcc_vid);
        regulator_disable(ts->vcc_vdd);
}

#define __GET_MT_TOOL_TYPE(type) ((type) == 0x01 ? MT_TOOL_FINGER : MT_TOOL_PEN)

static void hideep_report_slot(struct input_dev *input,
                               const struct hideep_event *event)
{
        input_mt_slot(input, event->index & 0x0f);
        input_mt_report_slot_state(input,
                                   __GET_MT_TOOL_TYPE(event->type),
                                   !(event->flag & HIDEEP_MT_RELEASED));
        if (!(event->flag & HIDEEP_MT_RELEASED)) {
                input_report_abs(input, ABS_MT_POSITION_X,
                                 le16_to_cpup(&event->x));
                input_report_abs(input, ABS_MT_POSITION_Y,
                                 le16_to_cpup(&event->y));
                input_report_abs(input, ABS_MT_PRESSURE,
                                 le16_to_cpup(&event->z));
                input_report_abs(input, ABS_MT_TOUCH_MAJOR, event->w);
        }
}

static void hideep_parse_and_report(struct hideep_ts *ts)
{
        const struct hideep_event *events =
                        (void *)&ts->xfer_buf[HIDEEP_TOUCH_EVENT_INDEX];
        const u8 *keys = &ts->xfer_buf[HIDEEP_KEY_EVENT_INDEX];
        int touch_count = ts->xfer_buf[0];
        int key_count = ts->xfer_buf[1] & 0x0f;
        int lpm_count = ts->xfer_buf[1] & 0xf0;
        int i;

        /* get touch event count */
        dev_dbg(&ts->client->dev, "mt = %d, key = %d, lpm = %02x",
                touch_count, key_count, lpm_count);

        touch_count = min(touch_count, HIDEEP_MT_MAX);
        for (i = 0; i < touch_count; i++)
                hideep_report_slot(ts->input_dev, events + i);

        key_count = min(key_count, HIDEEP_KEY_MAX);
        for (i = 0; i < key_count; i++) {
                u8 key_data = keys[i * 2];

                input_report_key(ts->input_dev,
                                 ts->key_codes[key_data & HIDEEP_KEY_IDX_MASK],
                                 key_data & HIDEEP_KEY_PRESSED_MASK);
        }

        input_mt_sync_frame(ts->input_dev);
        input_sync(ts->input_dev);
}

static irqreturn_t hideep_irq(int irq, void *handle)
{
        struct hideep_ts *ts = handle;
        int error;

        BUILD_BUG_ON(HIDEEP_MAX_EVENT > HIDEEP_XFER_BUF_SIZE);

        error = regmap_bulk_read(ts->reg, HIDEEP_EVENT_ADDR,
                                 ts->xfer_buf, HIDEEP_MAX_EVENT / 2);
        if (error) {
                dev_err(&ts->client->dev, "failed to read events: %d\n", error);
                goto out;
        }

        hideep_parse_and_report(ts);

out:
        return IRQ_HANDLED;
}

static int hideep_get_axis_info(struct hideep_ts *ts)
{
        __le16 val[2];
        int error;

        error = regmap_bulk_read(ts->reg, 0x28, val, ARRAY_SIZE(val));
        if (error)
                return error;

        ts->prop.max_x = le16_to_cpup(val);
        ts->prop.max_y = le16_to_cpup(val + 1);

        dev_dbg(&ts->client->dev, "X: %d, Y: %d",
                ts->prop.max_x, ts->prop.max_y);

        return 0;
}

static int hideep_init_input(struct hideep_ts *ts)
{
        struct device *dev = &ts->client->dev;
        int i;
        int error;

        ts->input_dev = devm_input_allocate_device(dev);
        if (!ts->input_dev) {
                dev_err(dev, "failed to allocate input device\n");
                return -ENOMEM;
        }

        ts->input_dev->name = HIDEEP_TS_NAME;
        ts->input_dev->id.bustype = BUS_I2C;
        input_set_drvdata(ts->input_dev, ts);

        input_set_capability(ts->input_dev, EV_ABS, ABS_MT_POSITION_X);
        input_set_capability(ts->input_dev, EV_ABS, ABS_MT_POSITION_Y);
        input_set_abs_params(ts->input_dev, ABS_MT_PRESSURE, 0, 65535, 0, 0);
        input_set_abs_params(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
        input_set_abs_params(ts->input_dev, ABS_MT_TOOL_TYPE,
                             0, MT_TOOL_MAX, 0, 0);
        touchscreen_parse_properties(ts->input_dev, true, &ts->prop);

        if (ts->prop.max_x == 0 || ts->prop.max_y == 0) {
                error = hideep_get_axis_info(ts);
                if (error)
                        return error;
        }

        error = input_mt_init_slots(ts->input_dev, HIDEEP_MT_MAX,
                                    INPUT_MT_DIRECT);
        if (error)
                return error;

        ts->key_num = device_property_count_u32(dev, "linux,keycodes");
        if (ts->key_num > HIDEEP_KEY_MAX) {
                dev_err(dev, "too many keys defined: %d\n",
                        ts->key_num);
                return -EINVAL;
        }

        if (ts->key_num <= 0) {
                dev_dbg(dev,
                        "missing or malformed 'linux,keycodes' property\n");
        } else {
                error = device_property_read_u32_array(dev, "linux,keycodes",
                                                       ts->key_codes,
                                                       ts->key_num);
                if (error) {
                        dev_dbg(dev, "failed to read keymap: %d", error);
                        return error;
                }

                if (ts->key_num) {
                        ts->input_dev->keycode = ts->key_codes;
                        ts->input_dev->keycodesize = sizeof(ts->key_codes[0]);
                        ts->input_dev->keycodemax = ts->key_num;

                        for (i = 0; i < ts->key_num; i++)
                                input_set_capability(ts->input_dev, EV_KEY,
                                        ts->key_codes[i]);
                }
        }

        error = input_register_device(ts->input_dev);
        if (error) {
                dev_err(dev, "failed to register input device: %d", error);
                return error;
        }

        return 0;
}

static ssize_t hideep_update_fw(struct device *dev,
                                struct device_attribute *attr,
                                const char *buf, size_t count)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct hideep_ts *ts = i2c_get_clientdata(client);
        const struct firmware *fw_entry;
        char *fw_name;
        int mode;
        int error;

        error = kstrtoint(buf, 0, &mode);
        if (error)
                return error;

        fw_name = kasprintf(GFP_KERNEL, "hideep_ts_%04x.bin",
                            be16_to_cpu(ts->dwz_info.product_id));
        if (!fw_name)
                return -ENOMEM;

        error = request_firmware(&fw_entry, fw_name, dev);
        if (error) {
                dev_err(dev, "failed to request firmware %s: %d",
                        fw_name, error);
                goto out_free_fw_name;
        }

        if (fw_entry->size % sizeof(__be32)) {
                dev_err(dev, "invalid firmware size %zu\n", fw_entry->size);
                error = -EINVAL;
                goto out_release_fw;
        }

        if (fw_entry->size > ts->fw_size) {
                dev_err(dev, "fw size (%zu) is too big (memory size %d)\n",
                        fw_entry->size, ts->fw_size);
                error = -EFBIG;
                goto out_release_fw;
        }

        mutex_lock(&ts->dev_mutex);
        disable_irq(client->irq);

        error = hideep_update_firmware(ts, (const __be32 *)fw_entry->data,
                                       fw_entry->size);

        enable_irq(client->irq);
        mutex_unlock(&ts->dev_mutex);

out_release_fw:
        release_firmware(fw_entry);
out_free_fw_name:
        kfree(fw_name);

        return error ?: count;
}

static ssize_t hideep_fw_version_show(struct device *dev,
                                      struct device_attribute *attr, char *buf)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct hideep_ts *ts = i2c_get_clientdata(client);
        ssize_t len;

        mutex_lock(&ts->dev_mutex);
        len = sysfs_emit(buf, "%04x\n", be16_to_cpu(ts->dwz_info.release_ver));
        mutex_unlock(&ts->dev_mutex);

        return len;
}

static ssize_t hideep_product_id_show(struct device *dev,
                                      struct device_attribute *attr, char *buf)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct hideep_ts *ts = i2c_get_clientdata(client);
        ssize_t len;

        mutex_lock(&ts->dev_mutex);
        len = sysfs_emit(buf, "%04x\n", be16_to_cpu(ts->dwz_info.product_id));
        mutex_unlock(&ts->dev_mutex);

        return len;
}

static DEVICE_ATTR(version, 0664, hideep_fw_version_show, NULL);
static DEVICE_ATTR(product_id, 0664, hideep_product_id_show, NULL);
static DEVICE_ATTR(update_fw, 0664, NULL, hideep_update_fw);

static struct attribute *hideep_ts_attrs[] = {
        &dev_attr_version.attr,
        &dev_attr_product_id.attr,
        &dev_attr_update_fw.attr,
        NULL,
};
ATTRIBUTE_GROUPS(hideep_ts);

static void hideep_set_work_mode(struct hideep_ts *ts)
{
        /*
         * Reset touch report format to the native HiDeep 20 protocol if requested.
         * This is necessary to make touchscreens which come up in I2C-HID mode
         * work with this driver.
         *
         * Note this is a kernel internal device-property set by x86 platform code,
         * this MUST not be used in devicetree files without first adding it to
         * the DT bindings.
         */
        if (device_property_read_bool(&ts->client->dev, "hideep,force-native-protocol"))
                regmap_write(ts->reg, HIDEEP_WORK_MODE, 0x00);
}

static int hideep_suspend(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct hideep_ts *ts = i2c_get_clientdata(client);

        disable_irq(client->irq);
        hideep_power_off(ts);

        return 0;
}

static int hideep_resume(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct hideep_ts *ts = i2c_get_clientdata(client);
        int error;

        error = hideep_power_on(ts);
        if (error) {
                dev_err(&client->dev, "power on failed");
                return error;
        }

        hideep_set_work_mode(ts);

        enable_irq(client->irq);

        return 0;
}

static DEFINE_SIMPLE_DEV_PM_OPS(hideep_pm_ops, hideep_suspend, hideep_resume);

static const struct regmap_config hideep_regmap_config = {
        .reg_bits = 16,
        .reg_format_endian = REGMAP_ENDIAN_LITTLE,
        .val_bits = 16,
        .val_format_endian = REGMAP_ENDIAN_LITTLE,
        .max_register = 0xffff,
};

static int hideep_probe(struct i2c_client *client)
{
        struct hideep_ts *ts;
        int error;

        /* check i2c bus */
        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
                dev_err(&client->dev, "check i2c device error");
                return -ENODEV;
        }

        if (client->irq <= 0) {
                dev_err(&client->dev, "missing irq: %d\n", client->irq);
                return -EINVAL;
        }

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

        ts->client = client;
        i2c_set_clientdata(client, ts);
        mutex_init(&ts->dev_mutex);

        ts->reg = devm_regmap_init_i2c(client, &hideep_regmap_config);
        if (IS_ERR(ts->reg)) {
                error = PTR_ERR(ts->reg);
                dev_err(&client->dev,
                        "failed to initialize regmap: %d\n", error);
                return error;
        }

        ts->vcc_vdd = devm_regulator_get(&client->dev, "vdd");
        if (IS_ERR(ts->vcc_vdd))
                return PTR_ERR(ts->vcc_vdd);

        ts->vcc_vid = devm_regulator_get(&client->dev, "vid");
        if (IS_ERR(ts->vcc_vid))
                return PTR_ERR(ts->vcc_vid);

        ts->reset_gpio = devm_gpiod_get_optional(&client->dev,
                                                 "reset", GPIOD_OUT_HIGH);
        if (IS_ERR(ts->reset_gpio))
                return PTR_ERR(ts->reset_gpio);

        error = hideep_power_on(ts);
        if (error) {
                dev_err(&client->dev, "power on failed: %d\n", error);
                return error;
        }

        error = devm_add_action_or_reset(&client->dev, hideep_power_off, ts);
        if (error)
                return error;

        error = hideep_load_dwz(ts);
        if (error) {
                dev_err(&client->dev, "failed to load dwz: %d", error);
                return error;
        }

        hideep_set_work_mode(ts);

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

        error = devm_request_threaded_irq(&client->dev, client->irq,
                                          NULL, hideep_irq, IRQF_ONESHOT,
                                          client->name, ts);
        if (error) {
                dev_err(&client->dev, "failed to request irq %d: %d\n",
                        client->irq, error);
                return error;
        }

        return 0;
}

static const struct i2c_device_id hideep_i2c_id[] = {
        { HIDEEP_I2C_NAME },
        { }
};
MODULE_DEVICE_TABLE(i2c, hideep_i2c_id);

#ifdef CONFIG_ACPI
static const struct acpi_device_id hideep_acpi_id[] = {
        { "HIDP0001", 0 },
        { }
};
MODULE_DEVICE_TABLE(acpi, hideep_acpi_id);
#endif

#ifdef CONFIG_OF
static const struct of_device_id hideep_match_table[] = {
        { .compatible = "hideep,hideep-ts" },
        { }
};
MODULE_DEVICE_TABLE(of, hideep_match_table);
#endif

static struct i2c_driver hideep_driver = {
        .driver = {
                .name                   = HIDEEP_I2C_NAME,
                .dev_groups             = hideep_ts_groups,
                .of_match_table         = of_match_ptr(hideep_match_table),
                .acpi_match_table       = ACPI_PTR(hideep_acpi_id),
                .pm                     = pm_sleep_ptr(&hideep_pm_ops),
        },
        .id_table       = hideep_i2c_id,
        .probe          = hideep_probe,
};

module_i2c_driver(hideep_driver);

MODULE_DESCRIPTION("Driver for HiDeep Touchscreen Controller");
MODULE_AUTHOR("anthony.kim@hideep.com");
MODULE_LICENSE("GPL v2");