root/drivers/input/touchscreen/ilitek_ts_i2c.c
// SPDX-License-Identifier: GPL-2.0
/*
 * ILITEK Touch IC driver for 23XX, 25XX and Lego series
 *
 * Copyright (C) 2011 ILI Technology Corporation.
 * Copyright (C) 2020 Luca Hsu <luca_hsu@ilitek.com>
 * Copyright (C) 2021 Joe Hung <joe_hung@ilitek.com>
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/gpio/consumer.h>
#include <linux/errno.h>
#include <linux/acpi.h>
#include <linux/input/touchscreen.h>
#include <linux/unaligned.h>


#define ILITEK_TS_NAME                                  "ilitek_ts"
#define BL_V1_8                                         0x108
#define BL_V1_7                                         0x107
#define BL_V1_6                                         0x106

#define ILITEK_TP_CMD_GET_TP_RES                        0x20
#define ILITEK_TP_CMD_GET_SCRN_RES                      0x21
#define ILITEK_TP_CMD_SET_IC_SLEEP                      0x30
#define ILITEK_TP_CMD_SET_IC_WAKE                       0x31
#define ILITEK_TP_CMD_GET_FW_VER                        0x40
#define ILITEK_TP_CMD_GET_PRL_VER                       0x42
#define ILITEK_TP_CMD_GET_MCU_VER                       0x61
#define ILITEK_TP_CMD_GET_IC_MODE                       0xC0

#define ILITEK_TP_I2C_REPORT_ID                         0x48

#define REPORT_COUNT_ADDRESS                            61
#define ILITEK_SUPPORT_MAX_POINT                        40

struct ilitek_protocol_info {
        u16 ver;
        u8 ver_major;
};

struct ilitek_ts_data {
        struct i2c_client               *client;
        struct gpio_desc                *reset_gpio;
        struct input_dev                *input_dev;
        struct touchscreen_properties   prop;

        const struct ilitek_protocol_map *ptl_cb_func;
        struct ilitek_protocol_info     ptl;

        char                            product_id[30];
        u16                             mcu_ver;
        u8                              ic_mode;
        u8                              firmware_ver[8];

        s32                             reset_time;
        s32                             screen_max_x;
        s32                             screen_max_y;
        s32                             screen_min_x;
        s32                             screen_min_y;
        s32                             max_tp;
};

struct ilitek_protocol_map {
        u16 cmd;
        const char *name;
        int (*func)(struct ilitek_ts_data *ts, u16 cmd, u8 *inbuf, u8 *outbuf);
};

enum ilitek_cmds {
        /* common cmds */
        GET_PTL_VER = 0,
        GET_FW_VER,
        GET_SCRN_RES,
        GET_TP_RES,
        GET_IC_MODE,
        GET_MCU_VER,
        SET_IC_SLEEP,
        SET_IC_WAKE,

        /* ALWAYS keep at the end */
        MAX_CMD_CNT
};

/* ILITEK I2C R/W APIs */
static int ilitek_i2c_write_and_read(struct ilitek_ts_data *ts,
                                     u8 *cmd, int write_len, int delay,
                                     u8 *data, int read_len)
{
        int error;
        struct i2c_client *client = ts->client;
        struct i2c_msg msgs[] = {
                {
                        .addr = client->addr,
                        .flags = 0,
                        .len = write_len,
                        .buf = cmd,
                },
                {
                        .addr = client->addr,
                        .flags = I2C_M_RD,
                        .len = read_len,
                        .buf = data,
                },
        };

        if (delay == 0 && write_len > 0 && read_len > 0) {
                error = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
                if (error < 0)
                        return error;
        } else {
                if (write_len > 0) {
                        error = i2c_transfer(client->adapter, msgs, 1);
                        if (error < 0)
                                return error;
                }
                if (delay > 0)
                        fsleep(delay * 1000);

                if (read_len > 0) {
                        error = i2c_transfer(client->adapter, msgs + 1, 1);
                        if (error < 0)
                                return error;
                }
        }

        return 0;
}

/* ILITEK ISR APIs */
static void ilitek_touch_down(struct ilitek_ts_data *ts, unsigned int id,
                              unsigned int x, unsigned int y)
{
        struct input_dev *input = ts->input_dev;

        input_mt_slot(input, id);
        input_mt_report_slot_state(input, MT_TOOL_FINGER, true);

        touchscreen_report_pos(input, &ts->prop, x, y, true);
}

static int ilitek_process_and_report_v6(struct ilitek_ts_data *ts)
{
        int error = 0;
        u8 buf[512];
        int packet_len = 5;
        int packet_max_point = 10;
        int report_max_point;
        int i, count;
        struct input_dev *input = ts->input_dev;
        struct device *dev = &ts->client->dev;
        unsigned int x, y, status, id;

        error = ilitek_i2c_write_and_read(ts, NULL, 0, 0, buf, 64);
        if (error) {
                dev_err(dev, "get touch info failed, err:%d\n", error);
                return error;
        }

        if (buf[0] != ILITEK_TP_I2C_REPORT_ID) {
                dev_err(dev, "get touch info failed. Wrong id: 0x%02X\n", buf[0]);
                return -EINVAL;
        }

        report_max_point = buf[REPORT_COUNT_ADDRESS];
        if (report_max_point > ts->max_tp) {
                dev_err(dev, "FW report max point:%d > panel info. max:%d\n",
                        report_max_point, ts->max_tp);
                return -EINVAL;
        }

        count = DIV_ROUND_UP(report_max_point, packet_max_point);
        for (i = 1; i < count; i++) {
                error = ilitek_i2c_write_and_read(ts, NULL, 0, 0,
                                                  buf + i * 64, 64);
                if (error) {
                        dev_err(dev, "get touch info. failed, cnt:%d, err:%d\n",
                                count, error);
                        return error;
                }
        }

        for (i = 0; i < report_max_point; i++) {
                status = buf[i * packet_len + 1] & 0x40;
                if (!status)
                        continue;

                id = buf[i * packet_len + 1] & 0x3F;

                x = get_unaligned_le16(buf + i * packet_len + 2);
                y = get_unaligned_le16(buf + i * packet_len + 4);

                if (x > ts->screen_max_x || x < ts->screen_min_x ||
                    y > ts->screen_max_y || y < ts->screen_min_y) {
                        dev_warn(dev, "invalid position, X[%d,%u,%d], Y[%d,%u,%d]\n",
                                 ts->screen_min_x, x, ts->screen_max_x,
                                 ts->screen_min_y, y, ts->screen_max_y);
                        continue;
                }

                ilitek_touch_down(ts, id, x, y);
        }

        input_mt_sync_frame(input);
        input_sync(input);

        return 0;
}

/* APIs of cmds for ILITEK Touch IC */
static int api_protocol_set_cmd(struct ilitek_ts_data *ts,
                                u16 idx, u8 *inbuf, u8 *outbuf)
{
        u16 cmd;
        int error;

        if (idx >= MAX_CMD_CNT)
                return -EINVAL;

        cmd = ts->ptl_cb_func[idx].cmd;
        error = ts->ptl_cb_func[idx].func(ts, cmd, inbuf, outbuf);
        if (error)
                return error;

        return 0;
}

static int api_protocol_get_ptl_ver(struct ilitek_ts_data *ts,
                                    u16 cmd, u8 *inbuf, u8 *outbuf)
{
        int error;
        u8 buf[64];

        buf[0] = cmd;
        error = ilitek_i2c_write_and_read(ts, buf, 1, 5, outbuf, 3);
        if (error)
                return error;

        ts->ptl.ver = get_unaligned_be16(outbuf);
        ts->ptl.ver_major = outbuf[0];

        return 0;
}

static int api_protocol_get_mcu_ver(struct ilitek_ts_data *ts,
                                    u16 cmd, u8 *inbuf, u8 *outbuf)
{
        int error;
        u8 buf[64];

        buf[0] = cmd;
        error = ilitek_i2c_write_and_read(ts, buf, 1, 5, outbuf, 32);
        if (error)
                return error;

        ts->mcu_ver = get_unaligned_le16(outbuf);
        memset(ts->product_id, 0, sizeof(ts->product_id));
        memcpy(ts->product_id, outbuf + 6, 26);

        return 0;
}

static int api_protocol_get_fw_ver(struct ilitek_ts_data *ts,
                                   u16 cmd, u8 *inbuf, u8 *outbuf)
{
        int error;
        u8 buf[64];

        buf[0] = cmd;
        error = ilitek_i2c_write_and_read(ts, buf, 1, 5, outbuf, 8);
        if (error)
                return error;

        memcpy(ts->firmware_ver, outbuf, 8);

        return 0;
}

static int api_protocol_get_scrn_res(struct ilitek_ts_data *ts,
                                     u16 cmd, u8 *inbuf, u8 *outbuf)
{
        int error;
        u8 buf[64];

        buf[0] = cmd;
        error = ilitek_i2c_write_and_read(ts, buf, 1, 5, outbuf, 8);
        if (error)
                return error;

        ts->screen_min_x = get_unaligned_le16(outbuf);
        ts->screen_min_y = get_unaligned_le16(outbuf + 2);
        ts->screen_max_x = get_unaligned_le16(outbuf + 4);
        ts->screen_max_y = get_unaligned_le16(outbuf + 6);

        return 0;
}

static int api_protocol_get_tp_res(struct ilitek_ts_data *ts,
                                   u16 cmd, u8 *inbuf, u8 *outbuf)
{
        int error;
        u8 buf[64];

        buf[0] = cmd;
        error = ilitek_i2c_write_and_read(ts, buf, 1, 5, outbuf, 15);
        if (error)
                return error;

        ts->max_tp = outbuf[8];
        if (ts->max_tp > ILITEK_SUPPORT_MAX_POINT) {
                dev_err(&ts->client->dev, "Invalid MAX_TP:%d from FW\n",
                        ts->max_tp);
                return -EINVAL;
        }

        return 0;
}

static int api_protocol_get_ic_mode(struct ilitek_ts_data *ts,
                                    u16 cmd, u8 *inbuf, u8 *outbuf)
{
        int error;
        u8 buf[64];

        buf[0] = cmd;
        error = ilitek_i2c_write_and_read(ts, buf, 1, 5, outbuf, 2);
        if (error)
                return error;

        ts->ic_mode = outbuf[0];
        return 0;
}

static int api_protocol_set_ic_sleep(struct ilitek_ts_data *ts,
                                     u16 cmd, u8 *inbuf, u8 *outbuf)
{
        u8 buf[64];

        buf[0] = cmd;
        return ilitek_i2c_write_and_read(ts, buf, 1, 0, NULL, 0);
}

static int api_protocol_set_ic_wake(struct ilitek_ts_data *ts,
                                    u16 cmd, u8 *inbuf, u8 *outbuf)
{
        u8 buf[64];

        buf[0] = cmd;
        return ilitek_i2c_write_and_read(ts, buf, 1, 0, NULL, 0);
}

static const struct ilitek_protocol_map ptl_func_map[] = {
        /* common cmds */
        [GET_PTL_VER] = {
                ILITEK_TP_CMD_GET_PRL_VER, "GET_PTL_VER",
                api_protocol_get_ptl_ver
        },
        [GET_FW_VER] = {
                ILITEK_TP_CMD_GET_FW_VER, "GET_FW_VER",
                api_protocol_get_fw_ver
        },
        [GET_SCRN_RES] = {
                ILITEK_TP_CMD_GET_SCRN_RES, "GET_SCRN_RES",
                api_protocol_get_scrn_res
        },
        [GET_TP_RES] = {
                ILITEK_TP_CMD_GET_TP_RES, "GET_TP_RES",
                api_protocol_get_tp_res
        },
        [GET_IC_MODE] = {
                ILITEK_TP_CMD_GET_IC_MODE, "GET_IC_MODE",
                           api_protocol_get_ic_mode
        },
        [GET_MCU_VER] = {
                ILITEK_TP_CMD_GET_MCU_VER, "GET_MOD_VER",
                           api_protocol_get_mcu_ver
        },
        [SET_IC_SLEEP] = {
                ILITEK_TP_CMD_SET_IC_SLEEP, "SET_IC_SLEEP",
                api_protocol_set_ic_sleep
        },
        [SET_IC_WAKE] = {
                ILITEK_TP_CMD_SET_IC_WAKE, "SET_IC_WAKE",
                api_protocol_set_ic_wake
        },
};

/* Probe APIs */
static void ilitek_reset(struct ilitek_ts_data *ts, int delay)
{
        if (ts->reset_gpio) {
                gpiod_set_value_cansleep(ts->reset_gpio, 1);
                fsleep(10000);
                gpiod_set_value_cansleep(ts->reset_gpio, 0);
                fsleep(delay * 1000);
        }
}

static int ilitek_protocol_init(struct ilitek_ts_data *ts)
{
        int error;
        u8 outbuf[64];

        ts->ptl_cb_func = ptl_func_map;
        ts->reset_time = 600;

        error = api_protocol_set_cmd(ts, GET_PTL_VER, NULL, outbuf);
        if (error)
                return error;

        /* Protocol v3 is not support currently */
        if (ts->ptl.ver_major == 0x3 ||
            ts->ptl.ver == BL_V1_6 ||
            ts->ptl.ver == BL_V1_7)
                return -EINVAL;

        return 0;
}

static int ilitek_read_tp_info(struct ilitek_ts_data *ts, bool boot)
{
        u8 outbuf[256];
        int error;

        error = api_protocol_set_cmd(ts, GET_PTL_VER, NULL, outbuf);
        if (error)
                return error;

        error = api_protocol_set_cmd(ts, GET_MCU_VER, NULL, outbuf);
        if (error)
                return error;

        error = api_protocol_set_cmd(ts, GET_FW_VER, NULL, outbuf);
        if (error)
                return error;

        if (boot) {
                error = api_protocol_set_cmd(ts, GET_SCRN_RES, NULL,
                                             outbuf);
                if (error)
                        return error;
        }

        error = api_protocol_set_cmd(ts, GET_TP_RES, NULL, outbuf);
        if (error)
                return error;

        error = api_protocol_set_cmd(ts, GET_IC_MODE, NULL, outbuf);
        if (error)
                return error;

        return 0;
}

static int ilitek_input_dev_init(struct device *dev, struct ilitek_ts_data *ts)
{
        int error;
        struct input_dev *input;

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

        ts->input_dev = input;
        input->name = ILITEK_TS_NAME;
        input->id.bustype = BUS_I2C;

        __set_bit(INPUT_PROP_DIRECT, input->propbit);

        input_set_abs_params(input, ABS_MT_POSITION_X,
                             ts->screen_min_x, ts->screen_max_x, 0, 0);
        input_set_abs_params(input, ABS_MT_POSITION_Y,
                             ts->screen_min_y, ts->screen_max_y, 0, 0);

        touchscreen_parse_properties(input, true, &ts->prop);

        error = input_mt_init_slots(input, ts->max_tp,
                                    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
        if (error) {
                dev_err(dev, "initialize MT slots failed, err:%d\n", error);
                return error;
        }

        error = input_register_device(input);
        if (error) {
                dev_err(dev, "register input device failed, err:%d\n", error);
                return error;
        }

        return 0;
}

static irqreturn_t ilitek_i2c_isr(int irq, void *dev_id)
{
        struct ilitek_ts_data *ts = dev_id;
        int error;

        error = ilitek_process_and_report_v6(ts);
        if (error < 0) {
                dev_err(&ts->client->dev, "[%s] err:%d\n", __func__, error);
                return IRQ_NONE;
        }

        return IRQ_HANDLED;
}

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

        return sysfs_emit(buf,
                          "fw version: [%02X%02X.%02X%02X.%02X%02X.%02X%02X]\n",
                          ts->firmware_ver[0], ts->firmware_ver[1],
                          ts->firmware_ver[2], ts->firmware_ver[3],
                          ts->firmware_ver[4], ts->firmware_ver[5],
                          ts->firmware_ver[6], ts->firmware_ver[7]);
}
static DEVICE_ATTR_RO(firmware_version);

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

        return sysfs_emit(buf, "product id: [%04X], module: [%s]\n",
                          ts->mcu_ver, ts->product_id);
}
static DEVICE_ATTR_RO(product_id);

static struct attribute *ilitek_sysfs_attrs[] = {
        &dev_attr_firmware_version.attr,
        &dev_attr_product_id.attr,
        NULL
};
ATTRIBUTE_GROUPS(ilitek_sysfs);

static int ilitek_ts_i2c_probe(struct i2c_client *client)
{
        struct ilitek_ts_data *ts;
        struct device *dev = &client->dev;
        int error;

        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
                dev_err(dev, "i2c check functionality failed\n");
                return -ENXIO;
        }

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

        ts->client = client;
        i2c_set_clientdata(client, ts);

        ts->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
        if (IS_ERR(ts->reset_gpio)) {
                error = PTR_ERR(ts->reset_gpio);
                dev_err(dev, "request gpiod failed: %d", error);
                return error;
        }

        ilitek_reset(ts, 1000);

        error = ilitek_protocol_init(ts);
        if (error) {
                dev_err(dev, "protocol init failed: %d", error);
                return error;
        }

        error = ilitek_read_tp_info(ts, true);
        if (error) {
                dev_err(dev, "read tp info failed: %d", error);
                return error;
        }

        error = ilitek_input_dev_init(dev, ts);
        if (error) {
                dev_err(dev, "input dev init failed: %d", error);
                return error;
        }

        error = devm_request_threaded_irq(dev, ts->client->irq,
                                          NULL, ilitek_i2c_isr, IRQF_ONESHOT,
                                          "ilitek_touch_irq", ts);
        if (error) {
                dev_err(dev, "request threaded irq failed: %d\n", error);
                return error;
        }

        return 0;
}

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

        disable_irq(client->irq);

        if (!device_may_wakeup(dev)) {
                error = api_protocol_set_cmd(ts, SET_IC_SLEEP, NULL, NULL);
                if (error)
                        return error;
        }

        return 0;
}

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

        if (!device_may_wakeup(dev)) {
                error = api_protocol_set_cmd(ts, SET_IC_WAKE, NULL, NULL);
                if (error)
                        return error;

                ilitek_reset(ts, ts->reset_time);
        }

        enable_irq(client->irq);

        return 0;
}

static DEFINE_SIMPLE_DEV_PM_OPS(ilitek_pm_ops, ilitek_suspend, ilitek_resume);

static const struct i2c_device_id ilitek_ts_i2c_id[] = {
        { ILITEK_TS_NAME },
        { }
};
MODULE_DEVICE_TABLE(i2c, ilitek_ts_i2c_id);

#ifdef CONFIG_ACPI
static const struct acpi_device_id ilitekts_acpi_id[] = {
        { "ILTK0001", 0 },
        { },
};
MODULE_DEVICE_TABLE(acpi, ilitekts_acpi_id);
#endif

#ifdef CONFIG_OF
static const struct of_device_id ilitek_ts_i2c_match[] = {
        {.compatible = "ilitek,ili2130",},
        {.compatible = "ilitek,ili2131",},
        {.compatible = "ilitek,ili2132",},
        {.compatible = "ilitek,ili2316",},
        {.compatible = "ilitek,ili2322",},
        {.compatible = "ilitek,ili2323",},
        {.compatible = "ilitek,ili2326",},
        {.compatible = "ilitek,ili2520",},
        {.compatible = "ilitek,ili2521",},
        { },
};
MODULE_DEVICE_TABLE(of, ilitek_ts_i2c_match);
#endif

static struct i2c_driver ilitek_ts_i2c_driver = {
        .driver = {
                .name = ILITEK_TS_NAME,
                .dev_groups = ilitek_sysfs_groups,
                .pm = pm_sleep_ptr(&ilitek_pm_ops),
                .of_match_table = of_match_ptr(ilitek_ts_i2c_match),
                .acpi_match_table = ACPI_PTR(ilitekts_acpi_id),
        },
        .probe = ilitek_ts_i2c_probe,
        .id_table = ilitek_ts_i2c_id,
};
module_i2c_driver(ilitek_ts_i2c_driver);

MODULE_AUTHOR("ILITEK");
MODULE_DESCRIPTION("ILITEK I2C Touchscreen Driver");
MODULE_LICENSE("GPL");