// SPDX-License-Identifier: GPL-2.0
// STMicroelectronics FTS Touchscreen device driver
//
// Copyright (c) 2017 Samsung Electronics Co., Ltd.
// Copyright (c) 2017 Andi Shyti <andi@etezian.org>

#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>

/* I2C commands */
#define STMFTS_READ_INFO                        0x80
#define STMFTS_READ_STATUS                      0x84
#define STMFTS_READ_ONE_EVENT                   0x85
#define STMFTS_READ_ALL_EVENT                   0x86
#define STMFTS_LATEST_EVENT                     0x87
#define STMFTS_SLEEP_IN                         0x90
#define STMFTS_SLEEP_OUT                        0x91
#define STMFTS_MS_MT_SENSE_OFF                  0x92
#define STMFTS_MS_MT_SENSE_ON                   0x93
#define STMFTS_SS_HOVER_SENSE_OFF               0x94
#define STMFTS_SS_HOVER_SENSE_ON                0x95
#define STMFTS_MS_KEY_SENSE_OFF                 0x9a
#define STMFTS_MS_KEY_SENSE_ON                  0x9b
#define STMFTS_SYSTEM_RESET                     0xa0
#define STMFTS_CLEAR_EVENT_STACK                0xa1
#define STMFTS_FULL_FORCE_CALIBRATION           0xa2
#define STMFTS_MS_CX_TUNING                     0xa3
#define STMFTS_SS_CX_TUNING                     0xa4

/* events */
#define STMFTS_EV_NO_EVENT                      0x00
#define STMFTS_EV_MULTI_TOUCH_DETECTED          0x02
#define STMFTS_EV_MULTI_TOUCH_ENTER             0x03
#define STMFTS_EV_MULTI_TOUCH_LEAVE             0x04
#define STMFTS_EV_MULTI_TOUCH_MOTION            0x05
#define STMFTS_EV_HOVER_ENTER                   0x07
#define STMFTS_EV_HOVER_LEAVE                   0x08
#define STMFTS_EV_HOVER_MOTION                  0x09
#define STMFTS_EV_KEY_STATUS                    0x0e
#define STMFTS_EV_ERROR                         0x0f
#define STMFTS_EV_CONTROLLER_READY              0x10
#define STMFTS_EV_SLEEP_OUT_CONTROLLER_READY    0x11
#define STMFTS_EV_STATUS                        0x16
#define STMFTS_EV_DEBUG                         0xdb

/* multi touch related event masks */
#define STMFTS_MASK_EVENT_ID                    0x0f
#define STMFTS_MASK_TOUCH_ID                    0xf0
#define STMFTS_MASK_LEFT_EVENT                  0x0f
#define STMFTS_MASK_X_MSB                       0x0f
#define STMFTS_MASK_Y_LSB                       0xf0

/* key related event masks */
#define STMFTS_MASK_KEY_NO_TOUCH                0x00
#define STMFTS_MASK_KEY_MENU                    0x01
#define STMFTS_MASK_KEY_BACK                    0x02

#define STMFTS_EVENT_SIZE       8
#define STMFTS_STACK_DEPTH      32
#define STMFTS_DATA_MAX_SIZE    (STMFTS_EVENT_SIZE * STMFTS_STACK_DEPTH)
#define STMFTS_MAX_FINGERS      10
#define STMFTS_DEV_NAME         "stmfts"

enum stmfts_regulators {
        STMFTS_REGULATOR_VDD,
        STMFTS_REGULATOR_AVDD,
};

struct stmfts_data {
        struct i2c_client *client;
        struct input_dev *input;
        struct led_classdev led_cdev;
        struct mutex mutex;

        struct touchscreen_properties prop;

        struct regulator_bulk_data regulators[2];

        /*
         * Presence of ledvdd will be used also to check
         * whether the LED is supported.
         */
        struct regulator *ledvdd;

        u16 chip_id;
        u8 chip_ver;
        u16 fw_ver;
        u8 config_id;
        u8 config_ver;

        u8 data[STMFTS_DATA_MAX_SIZE];

        struct completion cmd_done;

        bool use_key;
        bool led_status;
        bool hover_enabled;
        bool running;
};

static int stmfts_brightness_set(struct led_classdev *led_cdev,
                                        enum led_brightness value)
{
        struct stmfts_data *sdata = container_of(led_cdev,
                                        struct stmfts_data, led_cdev);
        int err;

        if (value != sdata->led_status && sdata->ledvdd) {
                if (!value) {
                        regulator_disable(sdata->ledvdd);
                } else {
                        err = regulator_enable(sdata->ledvdd);
                        if (err) {
                                dev_warn(&sdata->client->dev,
                                         "failed to enable ledvdd regulator: %d\n",
                                         err);
                                return err;
                        }
                }
                sdata->led_status = value;
        }

        return 0;
}

static enum led_brightness stmfts_brightness_get(struct led_classdev *led_cdev)
{
        struct stmfts_data *sdata = container_of(led_cdev,
                                                struct stmfts_data, led_cdev);

        return !!regulator_is_enabled(sdata->ledvdd);
}

/*
 * We can't simply use i2c_smbus_read_i2c_block_data because we
 * need to read 256 bytes, which exceeds the 255-byte SMBus block limit.
 */
static int stmfts_read_events(struct stmfts_data *sdata)
{
        u8 cmd = STMFTS_READ_ALL_EVENT;
        struct i2c_msg msgs[2] = {
                {
                        .addr   = sdata->client->addr,
                        .len    = 1,
                        .buf    = &cmd,
                },
                {
                        .addr   = sdata->client->addr,
                        .flags  = I2C_M_RD,
                        .len    = STMFTS_DATA_MAX_SIZE,
                        .buf    = sdata->data,
                },
        };
        int ret;

        ret = i2c_transfer(sdata->client->adapter, msgs, ARRAY_SIZE(msgs));
        if (ret < 0)
                return ret;

        return ret == ARRAY_SIZE(msgs) ? 0 : -EIO;
}

static void stmfts_report_contact_event(struct stmfts_data *sdata,
                                        const u8 event[])
{
        u8 slot_id = (event[0] & STMFTS_MASK_TOUCH_ID) >> 4;
        u16 x = event[1] | ((event[2] & STMFTS_MASK_X_MSB) << 8);
        u16 y = (event[2] >> 4) | (event[3] << 4);
        u8 maj = event[4];
        u8 min = event[5];
        u8 orientation = event[6];
        u8 area = event[7];

        input_mt_slot(sdata->input, slot_id);

        input_mt_report_slot_state(sdata->input, MT_TOOL_FINGER, true);
        input_report_abs(sdata->input, ABS_MT_POSITION_X, x);
        input_report_abs(sdata->input, ABS_MT_POSITION_Y, y);
        input_report_abs(sdata->input, ABS_MT_TOUCH_MAJOR, maj);
        input_report_abs(sdata->input, ABS_MT_TOUCH_MINOR, min);
        input_report_abs(sdata->input, ABS_MT_PRESSURE, area);
        input_report_abs(sdata->input, ABS_MT_ORIENTATION, orientation);

        input_sync(sdata->input);
}

static void stmfts_report_contact_release(struct stmfts_data *sdata,
                                          const u8 event[])
{
        u8 slot_id = (event[0] & STMFTS_MASK_TOUCH_ID) >> 4;

        input_mt_slot(sdata->input, slot_id);
        input_mt_report_slot_inactive(sdata->input);

        input_sync(sdata->input);
}

static void stmfts_report_hover_event(struct stmfts_data *sdata,
                                      const u8 event[])
{
        u16 x = (event[2] << 4) | (event[4] >> 4);
        u16 y = (event[3] << 4) | (event[4] & STMFTS_MASK_Y_LSB);
        u8 z = event[5];

        input_report_abs(sdata->input, ABS_X, x);
        input_report_abs(sdata->input, ABS_Y, y);
        input_report_abs(sdata->input, ABS_DISTANCE, z);

        input_sync(sdata->input);
}

static void stmfts_report_key_event(struct stmfts_data *sdata, const u8 event[])
{
        switch (event[2]) {
        case 0:
                input_report_key(sdata->input, KEY_BACK, 0);
                input_report_key(sdata->input, KEY_MENU, 0);
                break;

        case STMFTS_MASK_KEY_BACK:
                input_report_key(sdata->input, KEY_BACK, 1);
                break;

        case STMFTS_MASK_KEY_MENU:
                input_report_key(sdata->input, KEY_MENU, 1);
                break;

        default:
                dev_warn(&sdata->client->dev,
                         "unknown key event: %#02x\n", event[2]);
                break;
        }

        input_sync(sdata->input);
}

static void stmfts_parse_events(struct stmfts_data *sdata)
{
        int i;

        for (i = 0; i < STMFTS_STACK_DEPTH; i++) {
                u8 *event = &sdata->data[i * STMFTS_EVENT_SIZE];

                switch (event[0]) {

                case STMFTS_EV_CONTROLLER_READY:
                case STMFTS_EV_SLEEP_OUT_CONTROLLER_READY:
                case STMFTS_EV_STATUS:
                        complete(&sdata->cmd_done);
                        fallthrough;

                case STMFTS_EV_NO_EVENT:
                case STMFTS_EV_DEBUG:
                        return;
                }

                switch (event[0] & STMFTS_MASK_EVENT_ID) {

                case STMFTS_EV_MULTI_TOUCH_ENTER:
                case STMFTS_EV_MULTI_TOUCH_MOTION:
                        stmfts_report_contact_event(sdata, event);
                        break;

                case STMFTS_EV_MULTI_TOUCH_LEAVE:
                        stmfts_report_contact_release(sdata, event);
                        break;

                case STMFTS_EV_HOVER_ENTER:
                case STMFTS_EV_HOVER_LEAVE:
                case STMFTS_EV_HOVER_MOTION:
                        stmfts_report_hover_event(sdata, event);
                        break;

                case STMFTS_EV_KEY_STATUS:
                        stmfts_report_key_event(sdata, event);
                        break;

                case STMFTS_EV_ERROR:
                        dev_warn(&sdata->client->dev,
                                        "error code: 0x%x%x%x%x%x%x",
                                        event[6], event[5], event[4],
                                        event[3], event[2], event[1]);
                        break;

                default:
                        dev_err(&sdata->client->dev,
                                "unknown event %#02x\n", event[0]);
                }
        }
}

static irqreturn_t stmfts_irq_handler(int irq, void *dev)
{
        struct stmfts_data *sdata = dev;
        int err;

        mutex_lock(&sdata->mutex);

        err = stmfts_read_events(sdata);
        if (unlikely(err))
                dev_err(&sdata->client->dev,
                        "failed to read events: %d\n", err);
        else
                stmfts_parse_events(sdata);

        mutex_unlock(&sdata->mutex);
        return IRQ_HANDLED;
}

static int stmfts_command(struct stmfts_data *sdata, const u8 cmd)
{
        int err;

        reinit_completion(&sdata->cmd_done);

        err = i2c_smbus_write_byte(sdata->client, cmd);
        if (err)
                return err;

        if (!wait_for_completion_timeout(&sdata->cmd_done,
                                         msecs_to_jiffies(1000)))
                return -ETIMEDOUT;

        return 0;
}

static int stmfts_input_open(struct input_dev *dev)
{
        struct stmfts_data *sdata = input_get_drvdata(dev);
        int err;

        err = pm_runtime_resume_and_get(&sdata->client->dev);
        if (err)
                return err;

        err = i2c_smbus_write_byte(sdata->client, STMFTS_MS_MT_SENSE_ON);
        if (err) {
                pm_runtime_put_sync(&sdata->client->dev);
                return err;
        }

        mutex_lock(&sdata->mutex);
        sdata->running = true;

        if (sdata->hover_enabled) {
                err = i2c_smbus_write_byte(sdata->client,
                                           STMFTS_SS_HOVER_SENSE_ON);
                if (err)
                        dev_warn(&sdata->client->dev,
                                 "failed to enable hover\n");
        }
        mutex_unlock(&sdata->mutex);

        if (sdata->use_key) {
                err = i2c_smbus_write_byte(sdata->client,
                                           STMFTS_MS_KEY_SENSE_ON);
                if (err)
                        /* I can still use only the touch screen */
                        dev_warn(&sdata->client->dev,
                                 "failed to enable touchkey\n");
        }

        return 0;
}

static void stmfts_input_close(struct input_dev *dev)
{
        struct stmfts_data *sdata = input_get_drvdata(dev);
        int err;

        err = i2c_smbus_write_byte(sdata->client, STMFTS_MS_MT_SENSE_OFF);
        if (err)
                dev_warn(&sdata->client->dev,
                         "failed to disable touchscreen: %d\n", err);

        mutex_lock(&sdata->mutex);

        sdata->running = false;

        if (sdata->hover_enabled) {
                err = i2c_smbus_write_byte(sdata->client,
                                           STMFTS_SS_HOVER_SENSE_OFF);
                if (err)
                        dev_warn(&sdata->client->dev,
                                 "failed to disable hover: %d\n", err);
        }
        mutex_unlock(&sdata->mutex);

        if (sdata->use_key) {
                err = i2c_smbus_write_byte(sdata->client,
                                           STMFTS_MS_KEY_SENSE_OFF);
                if (err)
                        dev_warn(&sdata->client->dev,
                                 "failed to disable touchkey: %d\n", err);
        }

        pm_runtime_put_sync(&sdata->client->dev);
}

static ssize_t stmfts_sysfs_chip_id(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        struct stmfts_data *sdata = dev_get_drvdata(dev);

        return sysfs_emit(buf, "%#x\n", sdata->chip_id);
}

static ssize_t stmfts_sysfs_chip_version(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        struct stmfts_data *sdata = dev_get_drvdata(dev);

        return sysfs_emit(buf, "%u\n", sdata->chip_ver);
}

static ssize_t stmfts_sysfs_fw_ver(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        struct stmfts_data *sdata = dev_get_drvdata(dev);

        return sysfs_emit(buf, "%u\n", sdata->fw_ver);
}

static ssize_t stmfts_sysfs_config_id(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        struct stmfts_data *sdata = dev_get_drvdata(dev);

        return sysfs_emit(buf, "%#x\n", sdata->config_id);
}

static ssize_t stmfts_sysfs_config_version(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        struct stmfts_data *sdata = dev_get_drvdata(dev);

        return sysfs_emit(buf, "%u\n", sdata->config_ver);
}

static ssize_t stmfts_sysfs_read_status(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        struct stmfts_data *sdata = dev_get_drvdata(dev);
        u8 status[4];
        int err;

        err = i2c_smbus_read_i2c_block_data(sdata->client, STMFTS_READ_STATUS,
                                            sizeof(status), status);
        if (err)
                return err;

        return sysfs_emit(buf, "%#02x\n", status[0]);
}

static ssize_t stmfts_sysfs_hover_enable_read(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        struct stmfts_data *sdata = dev_get_drvdata(dev);

        return sysfs_emit(buf, "%u\n", sdata->hover_enabled);
}

static ssize_t stmfts_sysfs_hover_enable_write(struct device *dev,
                                struct device_attribute *attr,
                                const char *buf, size_t len)
{
        struct stmfts_data *sdata = dev_get_drvdata(dev);
        unsigned long value;
        int err = 0;

        if (kstrtoul(buf, 0, &value))
                return -EINVAL;

        mutex_lock(&sdata->mutex);

        if (value && sdata->hover_enabled)
                goto out;

        if (sdata->running)
                err = i2c_smbus_write_byte(sdata->client,
                                           value ? STMFTS_SS_HOVER_SENSE_ON :
                                                   STMFTS_SS_HOVER_SENSE_OFF);

        if (!err)
                sdata->hover_enabled = !!value;

out:
        mutex_unlock(&sdata->mutex);

        return len;
}

static DEVICE_ATTR(chip_id, 0444, stmfts_sysfs_chip_id, NULL);
static DEVICE_ATTR(chip_version, 0444, stmfts_sysfs_chip_version, NULL);
static DEVICE_ATTR(fw_ver, 0444, stmfts_sysfs_fw_ver, NULL);
static DEVICE_ATTR(config_id, 0444, stmfts_sysfs_config_id, NULL);
static DEVICE_ATTR(config_version, 0444, stmfts_sysfs_config_version, NULL);
static DEVICE_ATTR(status, 0444, stmfts_sysfs_read_status, NULL);
static DEVICE_ATTR(hover_enable, 0644, stmfts_sysfs_hover_enable_read,
                                        stmfts_sysfs_hover_enable_write);

static struct attribute *stmfts_sysfs_attrs[] = {
        &dev_attr_chip_id.attr,
        &dev_attr_chip_version.attr,
        &dev_attr_fw_ver.attr,
        &dev_attr_config_id.attr,
        &dev_attr_config_version.attr,
        &dev_attr_status.attr,
        &dev_attr_hover_enable.attr,
        NULL
};
ATTRIBUTE_GROUPS(stmfts_sysfs);

static int stmfts_power_on(struct stmfts_data *sdata)
{
        int err;
        u8 reg[8];

        err = regulator_bulk_enable(ARRAY_SIZE(sdata->regulators),
                                    sdata->regulators);
        if (err)
                return err;

        /*
         * The datasheet does not specify the power on time, but considering
         * that the reset time is < 10ms, I sleep 20ms to be sure
         */
        msleep(20);

        err = i2c_smbus_read_i2c_block_data(sdata->client, STMFTS_READ_INFO,
                                            sizeof(reg), reg);
        if (err < 0)
                return err;
        if (err != sizeof(reg))
                return -EIO;

        sdata->chip_id = be16_to_cpup((__be16 *)&reg[6]);
        sdata->chip_ver = reg[0];
        sdata->fw_ver = be16_to_cpup((__be16 *)&reg[2]);
        sdata->config_id = reg[4];
        sdata->config_ver = reg[5];

        enable_irq(sdata->client->irq);

        msleep(50);

        err = stmfts_command(sdata, STMFTS_SYSTEM_RESET);
        if (err)
                return err;

        err = stmfts_command(sdata, STMFTS_SLEEP_OUT);
        if (err)
                return err;

        /* optional tuning */
        err = stmfts_command(sdata, STMFTS_MS_CX_TUNING);
        if (err)
                dev_warn(&sdata->client->dev,
                         "failed to perform mutual auto tune: %d\n", err);

        /* optional tuning */
        err = stmfts_command(sdata, STMFTS_SS_CX_TUNING);
        if (err)
                dev_warn(&sdata->client->dev,
                         "failed to perform self auto tune: %d\n", err);

        err = stmfts_command(sdata, STMFTS_FULL_FORCE_CALIBRATION);
        if (err)
                return err;

        /*
         * At this point no one is using the touchscreen
         * and I don't really care about the return value
         */
        (void) i2c_smbus_write_byte(sdata->client, STMFTS_SLEEP_IN);

        return 0;
}

static void stmfts_power_off(void *data)
{
        struct stmfts_data *sdata = data;

        disable_irq(sdata->client->irq);
        regulator_bulk_disable(ARRAY_SIZE(sdata->regulators),
                                                sdata->regulators);
}

static int stmfts_enable_led(struct stmfts_data *sdata)
{
        int err;

        /* get the regulator for powering the leds on */
        sdata->ledvdd = devm_regulator_get(&sdata->client->dev, "ledvdd");
        if (IS_ERR(sdata->ledvdd))
                return PTR_ERR(sdata->ledvdd);

        sdata->led_cdev.name = STMFTS_DEV_NAME;
        sdata->led_cdev.max_brightness = LED_ON;
        sdata->led_cdev.brightness = LED_OFF;
        sdata->led_cdev.brightness_set_blocking = stmfts_brightness_set;
        sdata->led_cdev.brightness_get = stmfts_brightness_get;

        err = devm_led_classdev_register(&sdata->client->dev, &sdata->led_cdev);
        if (err) {
                devm_regulator_put(sdata->ledvdd);
                return err;
        }

        return 0;
}

static int stmfts_probe(struct i2c_client *client)
{
        int err;
        struct stmfts_data *sdata;

        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
                                                I2C_FUNC_SMBUS_BYTE_DATA |
                                                I2C_FUNC_SMBUS_I2C_BLOCK))
                return -ENODEV;

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

        i2c_set_clientdata(client, sdata);

        sdata->client = client;
        mutex_init(&sdata->mutex);
        init_completion(&sdata->cmd_done);

        sdata->regulators[STMFTS_REGULATOR_VDD].supply = "vdd";
        sdata->regulators[STMFTS_REGULATOR_AVDD].supply = "avdd";
        err = devm_regulator_bulk_get(&client->dev,
                                      ARRAY_SIZE(sdata->regulators),
                                      sdata->regulators);
        if (err)
                return err;

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

        sdata->input->name = STMFTS_DEV_NAME;
        sdata->input->id.bustype = BUS_I2C;
        sdata->input->open = stmfts_input_open;
        sdata->input->close = stmfts_input_close;

        input_set_capability(sdata->input, EV_ABS, ABS_MT_POSITION_X);
        input_set_capability(sdata->input, EV_ABS, ABS_MT_POSITION_Y);
        touchscreen_parse_properties(sdata->input, true, &sdata->prop);

        input_set_abs_params(sdata->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
        input_set_abs_params(sdata->input, ABS_MT_TOUCH_MINOR, 0, 255, 0, 0);
        input_set_abs_params(sdata->input, ABS_MT_ORIENTATION, 0, 255, 0, 0);
        input_set_abs_params(sdata->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
        input_set_abs_params(sdata->input, ABS_DISTANCE, 0, 255, 0, 0);

        sdata->use_key = device_property_read_bool(&client->dev,
                                                   "touch-key-connected");
        if (sdata->use_key) {
                input_set_capability(sdata->input, EV_KEY, KEY_MENU);
                input_set_capability(sdata->input, EV_KEY, KEY_BACK);
        }

        err = input_mt_init_slots(sdata->input,
                                  STMFTS_MAX_FINGERS, INPUT_MT_DIRECT);
        if (err)
                return err;

        input_set_drvdata(sdata->input, sdata);

        /*
         * stmfts_power_on expects interrupt to be disabled, but
         * at this point the device is still off and I do not trust
         * the status of the irq line that can generate some spurious
         * interrupts. To be on the safe side it's better to not enable
         * the interrupts during their request.
         */
        err = devm_request_threaded_irq(&client->dev, client->irq,
                                        NULL, stmfts_irq_handler,
                                        IRQF_ONESHOT | IRQF_NO_AUTOEN,
                                        "stmfts_irq", sdata);
        if (err)
                return err;

        dev_dbg(&client->dev, "initializing ST-Microelectronics FTS...\n");

        err = stmfts_power_on(sdata);
        if (err)
                return err;

        err = devm_add_action_or_reset(&client->dev, stmfts_power_off, sdata);
        if (err)
                return err;

        err = input_register_device(sdata->input);
        if (err)
                return err;

        if (sdata->use_key) {
                err = stmfts_enable_led(sdata);
                if (err) {
                        /*
                         * Even if the LEDs have failed to be initialized and
                         * used in the driver, I can still use the device even
                         * without LEDs. The ledvdd regulator pointer will be
                         * used as a flag.
                         */
                        dev_warn(&client->dev, "unable to use touchkey leds\n");
                        sdata->ledvdd = NULL;
                }
        }

        pm_runtime_enable(&client->dev);
        device_enable_async_suspend(&client->dev);

        return 0;
}

static void stmfts_remove(struct i2c_client *client)
{
        pm_runtime_disable(&client->dev);
}

static int stmfts_runtime_suspend(struct device *dev)
{
        struct stmfts_data *sdata = dev_get_drvdata(dev);
        int ret;

        ret = i2c_smbus_write_byte(sdata->client, STMFTS_SLEEP_IN);
        if (ret)
                dev_warn(dev, "failed to suspend device: %d\n", ret);

        return ret;
}

static int stmfts_runtime_resume(struct device *dev)
{
        struct stmfts_data *sdata = dev_get_drvdata(dev);
        int ret;

        ret = i2c_smbus_write_byte(sdata->client, STMFTS_SLEEP_OUT);
        if (ret)
                dev_err(dev, "failed to resume device: %d\n", ret);

        return ret;
}

static int stmfts_suspend(struct device *dev)
{
        struct stmfts_data *sdata = dev_get_drvdata(dev);

        stmfts_power_off(sdata);

        return 0;
}

static int stmfts_resume(struct device *dev)
{
        struct stmfts_data *sdata = dev_get_drvdata(dev);

        return stmfts_power_on(sdata);
}

static const struct dev_pm_ops stmfts_pm_ops = {
        SYSTEM_SLEEP_PM_OPS(stmfts_suspend, stmfts_resume)
        RUNTIME_PM_OPS(stmfts_runtime_suspend, stmfts_runtime_resume, NULL)
};

#ifdef CONFIG_OF
static const struct of_device_id stmfts_of_match[] = {
        { .compatible = "st,stmfts", },
        { },
};
MODULE_DEVICE_TABLE(of, stmfts_of_match);
#endif

static const struct i2c_device_id stmfts_id[] = {
        { "stmfts" },
        { }
};
MODULE_DEVICE_TABLE(i2c, stmfts_id);

static struct i2c_driver stmfts_driver = {
        .driver = {
                .name = STMFTS_DEV_NAME,
                .dev_groups = stmfts_sysfs_groups,
                .of_match_table = of_match_ptr(stmfts_of_match),
                .pm = pm_ptr(&stmfts_pm_ops),
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
        },
        .probe = stmfts_probe,
        .remove = stmfts_remove,
        .id_table = stmfts_id,
};

module_i2c_driver(stmfts_driver);

MODULE_AUTHOR("Andi Shyti <andi.shyti@samsung.com>");
MODULE_DESCRIPTION("STMicroelectronics FTS Touch Screen");
MODULE_LICENSE("GPL v2");