// SPDX-License-Identifier: GPL-2.0+
/*
 * HID driver for Valve Steam Controller
 *
 * Copyright (c) 2018 Rodrigo Rivas Costa <rodrigorivascosta@gmail.com>
 * Copyright (c) 2022 Valve Software
 *
 * Supports both the wired and wireless interfaces.
 *
 * This controller has a builtin emulation of mouse and keyboard: the right pad
 * can be used as a mouse, the shoulder buttons are mouse buttons, A and B
 * buttons are ENTER and ESCAPE, and so on. This is implemented as additional
 * HID interfaces.
 *
 * This is known as the "lizard mode", because apparently lizards like to use
 * the computer from the coach, without a proper mouse and keyboard.
 *
 * This driver will disable the lizard mode when the input device is opened
 * and re-enable it when the input device is closed, so as not to break user
 * mode behaviour. The lizard_mode parameter can be used to change that.
 *
 * There are a few user space applications (notably Steam Client) that use
 * the hidraw interface directly to create input devices (XTest, uinput...).
 * In order to avoid breaking them this driver creates a layered hidraw device,
 * so it can detect when the client is running and then:
 *  - it will not send any command to the controller.
 *  - this input device will be removed, to avoid double input of the same
 *    user action.
 * When the client is closed, this input device will be created again.
 *
 * For additional functions, such as changing the right-pad margin or switching
 * the led, you can use the user-space tool at:
 *
 *   https://github.com/rodrigorc/steamctrl
 */

#include <linux/device.h>
#include <linux/input.h>
#include <linux/hid.h>
#include <linux/module.h>
#include <linux/workqueue.h>
#include <linux/mutex.h>
#include <linux/rcupdate.h>
#include <linux/delay.h>
#include <linux/power_supply.h>
#include "hid-ids.h"

MODULE_DESCRIPTION("HID driver for Valve Steam Controller");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Rodrigo Rivas Costa <rodrigorivascosta@gmail.com>");

static bool lizard_mode = true;

static DEFINE_MUTEX(steam_devices_lock);
static LIST_HEAD(steam_devices);

#define STEAM_QUIRK_WIRELESS            BIT(0)
#define STEAM_QUIRK_DECK                BIT(1)

/* Touch pads are 40 mm in diameter and 65535 units */
#define STEAM_PAD_RESOLUTION 1638
/* Trigger runs are about 5 mm and 256 units */
#define STEAM_TRIGGER_RESOLUTION 51
/* Joystick runs are about 5 mm and 256 units */
#define STEAM_JOYSTICK_RESOLUTION 51
/* Trigger runs are about 6 mm and 32768 units */
#define STEAM_DECK_TRIGGER_RESOLUTION 5461
/* Joystick runs are about 5 mm and 32768 units */
#define STEAM_DECK_JOYSTICK_RESOLUTION 6553
/* Accelerometer has 16 bit resolution and a range of +/- 2g */
#define STEAM_DECK_ACCEL_RES_PER_G 16384
#define STEAM_DECK_ACCEL_RANGE 32768
#define STEAM_DECK_ACCEL_FUZZ 32
/* Gyroscope has 16 bit resolution and a range of +/- 2000 dps */
#define STEAM_DECK_GYRO_RES_PER_DPS 16
#define STEAM_DECK_GYRO_RANGE 32768
#define STEAM_DECK_GYRO_FUZZ 1

#define STEAM_PAD_FUZZ 256

/*
 * Commands that can be sent in a feature report.
 * Thanks to Valve and SDL for the names.
 */
enum {
        ID_SET_DIGITAL_MAPPINGS         = 0x80,
        ID_CLEAR_DIGITAL_MAPPINGS       = 0x81,
        ID_GET_DIGITAL_MAPPINGS         = 0x82,
        ID_GET_ATTRIBUTES_VALUES        = 0x83,
        ID_GET_ATTRIBUTE_LABEL          = 0x84,
        ID_SET_DEFAULT_DIGITAL_MAPPINGS = 0x85,
        ID_FACTORY_RESET                = 0x86,
        ID_SET_SETTINGS_VALUES          = 0x87,
        ID_CLEAR_SETTINGS_VALUES        = 0x88,
        ID_GET_SETTINGS_VALUES          = 0x89,
        ID_GET_SETTING_LABEL            = 0x8A,
        ID_GET_SETTINGS_MAXS            = 0x8B,
        ID_GET_SETTINGS_DEFAULTS        = 0x8C,
        ID_SET_CONTROLLER_MODE          = 0x8D,
        ID_LOAD_DEFAULT_SETTINGS        = 0x8E,
        ID_TRIGGER_HAPTIC_PULSE         = 0x8F,
        ID_TURN_OFF_CONTROLLER          = 0x9F,

        ID_GET_DEVICE_INFO              = 0xA1,

        ID_CALIBRATE_TRACKPADS          = 0xA7,
        ID_RESERVED_0                   = 0xA8,
        ID_SET_SERIAL_NUMBER            = 0xA9,
        ID_GET_TRACKPAD_CALIBRATION     = 0xAA,
        ID_GET_TRACKPAD_FACTORY_CALIBRATION = 0xAB,
        ID_GET_TRACKPAD_RAW_DATA        = 0xAC,
        ID_ENABLE_PAIRING               = 0xAD,
        ID_GET_STRING_ATTRIBUTE         = 0xAE,
        ID_RADIO_ERASE_RECORDS          = 0xAF,
        ID_RADIO_WRITE_RECORD           = 0xB0,
        ID_SET_DONGLE_SETTING           = 0xB1,
        ID_DONGLE_DISCONNECT_DEVICE     = 0xB2,
        ID_DONGLE_COMMIT_DEVICE         = 0xB3,
        ID_DONGLE_GET_WIRELESS_STATE    = 0xB4,
        ID_CALIBRATE_GYRO               = 0xB5,
        ID_PLAY_AUDIO                   = 0xB6,
        ID_AUDIO_UPDATE_START           = 0xB7,
        ID_AUDIO_UPDATE_DATA            = 0xB8,
        ID_AUDIO_UPDATE_COMPLETE        = 0xB9,
        ID_GET_CHIPID                   = 0xBA,

        ID_CALIBRATE_JOYSTICK           = 0xBF,
        ID_CALIBRATE_ANALOG_TRIGGERS    = 0xC0,
        ID_SET_AUDIO_MAPPING            = 0xC1,
        ID_CHECK_GYRO_FW_LOAD           = 0xC2,
        ID_CALIBRATE_ANALOG             = 0xC3,
        ID_DONGLE_GET_CONNECTED_SLOTS   = 0xC4,

        ID_RESET_IMU                    = 0xCE,

        ID_TRIGGER_HAPTIC_CMD           = 0xEA,
        ID_TRIGGER_RUMBLE_CMD           = 0xEB,
};

/* Settings IDs */
enum {
        /* 0 */
        SETTING_MOUSE_SENSITIVITY,
        SETTING_MOUSE_ACCELERATION,
        SETTING_TRACKBALL_ROTATION_ANGLE,
        SETTING_HAPTIC_INTENSITY_UNUSED,
        SETTING_LEFT_GAMEPAD_STICK_ENABLED,
        SETTING_RIGHT_GAMEPAD_STICK_ENABLED,
        SETTING_USB_DEBUG_MODE,
        SETTING_LEFT_TRACKPAD_MODE,
        SETTING_RIGHT_TRACKPAD_MODE,
        SETTING_MOUSE_POINTER_ENABLED,

        /* 10 */
        SETTING_DPAD_DEADZONE,
        SETTING_MINIMUM_MOMENTUM_VEL,
        SETTING_MOMENTUM_DECAY_AMMOUNT,
        SETTING_TRACKPAD_RELATIVE_MODE_TICKS_PER_PIXEL,
        SETTING_HAPTIC_INCREMENT,
        SETTING_DPAD_ANGLE_SIN,
        SETTING_DPAD_ANGLE_COS,
        SETTING_MOMENTUM_VERTICAL_DIVISOR,
        SETTING_MOMENTUM_MAXIMUM_VELOCITY,
        SETTING_TRACKPAD_Z_ON,

        /* 20 */
        SETTING_TRACKPAD_Z_OFF,
        SETTING_SENSITIVY_SCALE_AMMOUNT,
        SETTING_LEFT_TRACKPAD_SECONDARY_MODE,
        SETTING_RIGHT_TRACKPAD_SECONDARY_MODE,
        SETTING_SMOOTH_ABSOLUTE_MOUSE,
        SETTING_STEAMBUTTON_POWEROFF_TIME,
        SETTING_UNUSED_1,
        SETTING_TRACKPAD_OUTER_RADIUS,
        SETTING_TRACKPAD_Z_ON_LEFT,
        SETTING_TRACKPAD_Z_OFF_LEFT,

        /* 30 */
        SETTING_TRACKPAD_OUTER_SPIN_VEL,
        SETTING_TRACKPAD_OUTER_SPIN_RADIUS,
        SETTING_TRACKPAD_OUTER_SPIN_HORIZONTAL_ONLY,
        SETTING_TRACKPAD_RELATIVE_MODE_DEADZONE,
        SETTING_TRACKPAD_RELATIVE_MODE_MAX_VEL,
        SETTING_TRACKPAD_RELATIVE_MODE_INVERT_Y,
        SETTING_TRACKPAD_DOUBLE_TAP_BEEP_ENABLED,
        SETTING_TRACKPAD_DOUBLE_TAP_BEEP_PERIOD,
        SETTING_TRACKPAD_DOUBLE_TAP_BEEP_COUNT,
        SETTING_TRACKPAD_OUTER_RADIUS_RELEASE_ON_TRANSITION,

        /* 40 */
        SETTING_RADIAL_MODE_ANGLE,
        SETTING_HAPTIC_INTENSITY_MOUSE_MODE,
        SETTING_LEFT_DPAD_REQUIRES_CLICK,
        SETTING_RIGHT_DPAD_REQUIRES_CLICK,
        SETTING_LED_BASELINE_BRIGHTNESS,
        SETTING_LED_USER_BRIGHTNESS,
        SETTING_ENABLE_RAW_JOYSTICK,
        SETTING_ENABLE_FAST_SCAN,
        SETTING_IMU_MODE,
        SETTING_WIRELESS_PACKET_VERSION,

        /* 50 */
        SETTING_SLEEP_INACTIVITY_TIMEOUT,
        SETTING_TRACKPAD_NOISE_THRESHOLD,
        SETTING_LEFT_TRACKPAD_CLICK_PRESSURE,
        SETTING_RIGHT_TRACKPAD_CLICK_PRESSURE,
        SETTING_LEFT_BUMPER_CLICK_PRESSURE,
        SETTING_RIGHT_BUMPER_CLICK_PRESSURE,
        SETTING_LEFT_GRIP_CLICK_PRESSURE,
        SETTING_RIGHT_GRIP_CLICK_PRESSURE,
        SETTING_LEFT_GRIP2_CLICK_PRESSURE,
        SETTING_RIGHT_GRIP2_CLICK_PRESSURE,

        /* 60 */
        SETTING_PRESSURE_MODE,
        SETTING_CONTROLLER_TEST_MODE,
        SETTING_TRIGGER_MODE,
        SETTING_TRACKPAD_Z_THRESHOLD,
        SETTING_FRAME_RATE,
        SETTING_TRACKPAD_FILT_CTRL,
        SETTING_TRACKPAD_CLIP,
        SETTING_DEBUG_OUTPUT_SELECT,
        SETTING_TRIGGER_THRESHOLD_PERCENT,
        SETTING_TRACKPAD_FREQUENCY_HOPPING,

        /* 70 */
        SETTING_HAPTICS_ENABLED,
        SETTING_STEAM_WATCHDOG_ENABLE,
        SETTING_TIMP_TOUCH_THRESHOLD_ON,
        SETTING_TIMP_TOUCH_THRESHOLD_OFF,
        SETTING_FREQ_HOPPING,
        SETTING_TEST_CONTROL,
        SETTING_HAPTIC_MASTER_GAIN_DB,
        SETTING_THUMB_TOUCH_THRESH,
        SETTING_DEVICE_POWER_STATUS,
        SETTING_HAPTIC_INTENSITY,

        /* 80 */
        SETTING_STABILIZER_ENABLED,
        SETTING_TIMP_MODE_MTE,
};

/* Input report identifiers */
enum
{
        ID_CONTROLLER_STATE = 1,
        ID_CONTROLLER_DEBUG = 2,
        ID_CONTROLLER_WIRELESS = 3,
        ID_CONTROLLER_STATUS = 4,
        ID_CONTROLLER_DEBUG2 = 5,
        ID_CONTROLLER_SECONDARY_STATE = 6,
        ID_CONTROLLER_BLE_STATE = 7,
        ID_CONTROLLER_DECK_STATE = 9
};

/* String attribute identifiers */
enum {
        ATTRIB_STR_BOARD_SERIAL,
        ATTRIB_STR_UNIT_SERIAL,
};

/* Values for GYRO_MODE (bitmask) */
enum {
        SETTING_GYRO_MODE_OFF                   = 0,
        SETTING_GYRO_MODE_STEERING              = BIT(0),
        SETTING_GYRO_MODE_TILT                  = BIT(1),
        SETTING_GYRO_MODE_SEND_ORIENTATION      = BIT(2),
        SETTING_GYRO_MODE_SEND_RAW_ACCEL        = BIT(3),
        SETTING_GYRO_MODE_SEND_RAW_GYRO         = BIT(4),
};

/* Trackpad modes */
enum {
        TRACKPAD_ABSOLUTE_MOUSE,
        TRACKPAD_RELATIVE_MOUSE,
        TRACKPAD_DPAD_FOUR_WAY_DISCRETE,
        TRACKPAD_DPAD_FOUR_WAY_OVERLAP,
        TRACKPAD_DPAD_EIGHT_WAY,
        TRACKPAD_RADIAL_MODE,
        TRACKPAD_ABSOLUTE_DPAD,
        TRACKPAD_NONE,
        TRACKPAD_GESTURE_KEYBOARD,
};

/* Pad identifiers for the deck */
#define STEAM_PAD_LEFT 0
#define STEAM_PAD_RIGHT 1
#define STEAM_PAD_BOTH 2

/* Other random constants */
#define STEAM_SERIAL_LEN 0x15

struct steam_device {
        struct list_head list;
        spinlock_t lock;
        struct hid_device *hdev, *client_hdev;
        struct mutex report_mutex;
        unsigned long client_opened;
        struct input_dev __rcu *input;
        struct input_dev __rcu *sensors;
        unsigned long quirks;
        struct work_struct work_connect;
        bool connected;
        char serial_no[STEAM_SERIAL_LEN + 1];
        struct power_supply_desc battery_desc;
        struct power_supply __rcu *battery;
        u8 battery_charge;
        u16 voltage;
        struct delayed_work mode_switch;
        bool did_mode_switch;
        bool gamepad_mode;
        struct work_struct rumble_work;
        u16 rumble_left;
        u16 rumble_right;
        unsigned int sensor_timestamp_us;
        struct work_struct unregister_work;
};

static int steam_recv_report(struct steam_device *steam,
                u8 *data, int size)
{
        struct hid_report *r;
        u8 *buf;
        int ret;

        r = steam->hdev->report_enum[HID_FEATURE_REPORT].report_id_hash[0];
        if (!r) {
                hid_err(steam->hdev, "No HID_FEATURE_REPORT submitted -  nothing to read\n");
                return -EINVAL;
        }

        if (hid_report_len(r) < 64)
                return -EINVAL;

        buf = hid_alloc_report_buf(r, GFP_KERNEL);
        if (!buf)
                return -ENOMEM;

        /*
         * The report ID is always 0, so strip the first byte from the output.
         * hid_report_len() is not counting the report ID, so +1 to the length
         * or else we get a EOVERFLOW. We are safe from a buffer overflow
         * because hid_alloc_report_buf() allocates +7 bytes.
         */
        ret = hid_hw_raw_request(steam->hdev, 0x00,
                        buf, hid_report_len(r) + 1,
                        HID_FEATURE_REPORT, HID_REQ_GET_REPORT);
        if (ret > 0)
                memcpy(data, buf + 1, min(size, ret - 1));
        kfree(buf);
        return ret;
}

static int steam_send_report(struct steam_device *steam,
                u8 *cmd, int size)
{
        struct hid_report *r;
        u8 *buf;
        unsigned int retries = 50;
        int ret;

        r = steam->hdev->report_enum[HID_FEATURE_REPORT].report_id_hash[0];
        if (!r) {
                hid_err(steam->hdev, "No HID_FEATURE_REPORT submitted -  nothing to read\n");
                return -EINVAL;
        }

        if (hid_report_len(r) < 64)
                return -EINVAL;

        buf = hid_alloc_report_buf(r, GFP_KERNEL);
        if (!buf)
                return -ENOMEM;

        /* The report ID is always 0 */
        memcpy(buf + 1, cmd, size);

        /*
         * Sometimes the wireless controller fails with EPIPE
         * when sending a feature report.
         * Doing a HID_REQ_GET_REPORT and waiting for a while
         * seems to fix that.
         */
        do {
                ret = hid_hw_raw_request(steam->hdev, 0,
                                buf, max(size, 64) + 1,
                                HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
                if (ret != -EPIPE)
                        break;
                msleep(20);
        } while (--retries);

        kfree(buf);
        if (ret < 0)
                hid_err(steam->hdev, "%s: error %d (%*ph)\n", __func__,
                                ret, size, cmd);
        return ret;
}

static inline int steam_send_report_byte(struct steam_device *steam, u8 cmd)
{
        return steam_send_report(steam, &cmd, 1);
}

static int steam_write_settings(struct steam_device *steam,
                /* u8 reg, u16 val */...)
{
        /* Send: 0x87 len (reg valLo valHi)* */
        u8 reg;
        u16 val;
        u8 cmd[64] = {ID_SET_SETTINGS_VALUES, 0x00};
        int ret;
        va_list args;

        va_start(args, steam);
        for (;;) {
                reg = va_arg(args, int);
                if (reg == 0)
                        break;
                val = va_arg(args, int);
                cmd[cmd[1] + 2] = reg;
                cmd[cmd[1] + 3] = val & 0xff;
                cmd[cmd[1] + 4] = val >> 8;
                cmd[1] += 3;
        }
        va_end(args);

        ret = steam_send_report(steam, cmd, 2 + cmd[1]);
        if (ret < 0)
                return ret;

        /*
         * Sometimes a lingering report for this command can
         * get read back instead of the last set report if
         * this isn't explicitly queried
         */
        return steam_recv_report(steam, cmd, 2 + cmd[1]);
}

static int steam_get_serial(struct steam_device *steam)
{
        /*
         * Send: 0xae 0x15 0x01
         * Recv: 0xae 0x15 0x01 serialnumber
         */
        int ret = 0;
        u8 cmd[] = {ID_GET_STRING_ATTRIBUTE, sizeof(steam->serial_no), ATTRIB_STR_UNIT_SERIAL};
        u8 reply[3 + STEAM_SERIAL_LEN + 1];

        mutex_lock(&steam->report_mutex);
        ret = steam_send_report(steam, cmd, sizeof(cmd));
        if (ret < 0)
                goto out;
        ret = steam_recv_report(steam, reply, sizeof(reply));
        if (ret < 0)
                goto out;
        if (reply[0] != ID_GET_STRING_ATTRIBUTE || reply[1] < 1 ||
            reply[1] > sizeof(steam->serial_no) || reply[2] != ATTRIB_STR_UNIT_SERIAL) {
                ret = -EIO;
                goto out;
        }
        reply[3 + STEAM_SERIAL_LEN] = 0;
        strscpy(steam->serial_no, reply + 3, reply[1]);
out:
        mutex_unlock(&steam->report_mutex);
        return ret;
}

/*
 * This command requests the wireless adaptor to post an event
 * with the connection status. Useful if this driver is loaded when
 * the controller is already connected.
 */
static inline int steam_request_conn_status(struct steam_device *steam)
{
        int ret;
        mutex_lock(&steam->report_mutex);
        ret = steam_send_report_byte(steam, ID_DONGLE_GET_WIRELESS_STATE);
        mutex_unlock(&steam->report_mutex);
        return ret;
}

/*
 * Send a haptic pulse to the trackpads
 * Duration and interval are measured in microseconds, count is the number
 * of pulses to send for duration time with interval microseconds between them
 * and gain is measured in decibels, ranging from -24 to +6
 */
static inline int steam_haptic_pulse(struct steam_device *steam, u8 pad,
                                u16 duration, u16 interval, u16 count, u8 gain)
{
        int ret;
        u8 report[10] = {ID_TRIGGER_HAPTIC_PULSE, 8};

        /* Left and right are swapped on this report for legacy reasons */
        if (pad < STEAM_PAD_BOTH)
                pad ^= 1;

        report[2] = pad;
        report[3] = duration & 0xFF;
        report[4] = duration >> 8;
        report[5] = interval & 0xFF;
        report[6] = interval >> 8;
        report[7] = count & 0xFF;
        report[8] = count >> 8;
        report[9] = gain;

        mutex_lock(&steam->report_mutex);
        ret = steam_send_report(steam, report, sizeof(report));
        mutex_unlock(&steam->report_mutex);
        return ret;
}

static inline int steam_haptic_rumble(struct steam_device *steam,
                                u16 intensity, u16 left_speed, u16 right_speed,
                                u8 left_gain, u8 right_gain)
{
        int ret;
        u8 report[11] = {ID_TRIGGER_RUMBLE_CMD, 9};

        report[3] = intensity & 0xFF;
        report[4] = intensity >> 8;
        report[5] = left_speed & 0xFF;
        report[6] = left_speed >> 8;
        report[7] = right_speed & 0xFF;
        report[8] = right_speed >> 8;
        report[9] = left_gain;
        report[10] = right_gain;

        mutex_lock(&steam->report_mutex);
        ret = steam_send_report(steam, report, sizeof(report));
        mutex_unlock(&steam->report_mutex);
        return ret;
}

static void steam_haptic_rumble_cb(struct work_struct *work)
{
        struct steam_device *steam = container_of(work, struct steam_device,
                                                        rumble_work);
        steam_haptic_rumble(steam, 0, steam->rumble_left,
                steam->rumble_right, 2, 0);
}

#ifdef CONFIG_STEAM_FF
static int steam_play_effect(struct input_dev *dev, void *data,
                                struct ff_effect *effect)
{
        struct steam_device *steam = input_get_drvdata(dev);

        steam->rumble_left = effect->u.rumble.strong_magnitude;
        steam->rumble_right = effect->u.rumble.weak_magnitude;

        return schedule_work(&steam->rumble_work);
}
#endif

static void steam_set_lizard_mode(struct steam_device *steam, bool enable)
{
        if (steam->gamepad_mode)
                enable = false;

        mutex_lock(&steam->report_mutex);
        if (enable) {
                /* enable esc, enter, cursors */
                steam_send_report_byte(steam, ID_SET_DEFAULT_DIGITAL_MAPPINGS);
                /* reset settings */
                steam_send_report_byte(steam, ID_LOAD_DEFAULT_SETTINGS);
        } else {
                /* disable esc, enter, cursor */
                steam_send_report_byte(steam, ID_CLEAR_DIGITAL_MAPPINGS);

                if (steam->quirks & STEAM_QUIRK_DECK) {
                        steam_write_settings(steam,
                                SETTING_LEFT_TRACKPAD_MODE, TRACKPAD_NONE, /* disable mouse */
                                SETTING_RIGHT_TRACKPAD_MODE, TRACKPAD_NONE, /* disable mouse */
                                SETTING_LEFT_TRACKPAD_CLICK_PRESSURE, 0xFFFF, /* disable haptic click */
                                SETTING_RIGHT_TRACKPAD_CLICK_PRESSURE, 0xFFFF, /* disable haptic click */
                                SETTING_STEAM_WATCHDOG_ENABLE, 0, /* disable watchdog that tests if Steam is active */
                                0);
                } else {
                        steam_write_settings(steam,
                                SETTING_LEFT_TRACKPAD_MODE, TRACKPAD_NONE, /* disable mouse */
                                SETTING_RIGHT_TRACKPAD_MODE, TRACKPAD_NONE, /* disable mouse */
                                0);
                }
        }
        mutex_unlock(&steam->report_mutex);
}

static int steam_input_open(struct input_dev *dev)
{
        struct steam_device *steam = input_get_drvdata(dev);
        unsigned long flags;
        bool set_lizard_mode;

        /*
         * Disabling lizard mode automatically is only done on the Steam
         * Controller. On the Steam Deck, this is toggled manually by holding
         * the options button instead, handled by steam_mode_switch_cb.
         */
        if (!(steam->quirks & STEAM_QUIRK_DECK)) {
                spin_lock_irqsave(&steam->lock, flags);
                set_lizard_mode = !steam->client_opened && lizard_mode;
                spin_unlock_irqrestore(&steam->lock, flags);
                if (set_lizard_mode)
                        steam_set_lizard_mode(steam, false);
        }

        return 0;
}

static void steam_input_close(struct input_dev *dev)
{
        struct steam_device *steam = input_get_drvdata(dev);
        unsigned long flags;
        bool set_lizard_mode;

        if (!(steam->quirks & STEAM_QUIRK_DECK)) {
                spin_lock_irqsave(&steam->lock, flags);
                set_lizard_mode = !steam->client_opened && lizard_mode;
                spin_unlock_irqrestore(&steam->lock, flags);
                if (set_lizard_mode)
                        steam_set_lizard_mode(steam, true);
        }
}

static enum power_supply_property steam_battery_props[] = {
        POWER_SUPPLY_PROP_PRESENT,
        POWER_SUPPLY_PROP_SCOPE,
        POWER_SUPPLY_PROP_VOLTAGE_NOW,
        POWER_SUPPLY_PROP_CAPACITY,
};

static int steam_battery_get_property(struct power_supply *psy,
                                enum power_supply_property psp,
                                union power_supply_propval *val)
{
        struct steam_device *steam = power_supply_get_drvdata(psy);
        unsigned long flags;
        s16 volts;
        u8 batt;
        int ret = 0;

        spin_lock_irqsave(&steam->lock, flags);
        volts = steam->voltage;
        batt = steam->battery_charge;
        spin_unlock_irqrestore(&steam->lock, flags);

        switch (psp) {
        case POWER_SUPPLY_PROP_PRESENT:
                val->intval = 1;
                break;
        case POWER_SUPPLY_PROP_SCOPE:
                val->intval = POWER_SUPPLY_SCOPE_DEVICE;
                break;
        case POWER_SUPPLY_PROP_VOLTAGE_NOW:
                val->intval = volts * 1000; /* mV -> uV */
                break;
        case POWER_SUPPLY_PROP_CAPACITY:
                val->intval = batt;
                break;
        default:
                ret = -EINVAL;
                break;
        }
        return ret;
}

static int steam_battery_register(struct steam_device *steam)
{
        struct power_supply *battery;
        struct power_supply_config battery_cfg = { .drv_data = steam, };
        unsigned long flags;
        int ret;

        steam->battery_desc.type = POWER_SUPPLY_TYPE_BATTERY;
        steam->battery_desc.properties = steam_battery_props;
        steam->battery_desc.num_properties = ARRAY_SIZE(steam_battery_props);
        steam->battery_desc.get_property = steam_battery_get_property;
        steam->battery_desc.name = devm_kasprintf(&steam->hdev->dev,
                        GFP_KERNEL, "steam-controller-%s-battery",
                        steam->serial_no);
        if (!steam->battery_desc.name)
                return -ENOMEM;

        /* avoid the warning of 0% battery while waiting for the first info */
        spin_lock_irqsave(&steam->lock, flags);
        steam->voltage = 3000;
        steam->battery_charge = 100;
        spin_unlock_irqrestore(&steam->lock, flags);

        battery = power_supply_register(&steam->hdev->dev,
                        &steam->battery_desc, &battery_cfg);
        if (IS_ERR(battery)) {
                ret = PTR_ERR(battery);
                hid_err(steam->hdev,
                                "%s:power_supply_register failed with error %d\n",
                                __func__, ret);
                return ret;
        }
        rcu_assign_pointer(steam->battery, battery);
        power_supply_powers(battery, &steam->hdev->dev);
        return 0;
}

static int steam_input_register(struct steam_device *steam)
{
        struct hid_device *hdev = steam->hdev;
        struct input_dev *input;
        int ret;

        rcu_read_lock();
        input = rcu_dereference(steam->input);
        rcu_read_unlock();
        if (input) {
                dbg_hid("%s: already connected\n", __func__);
                return 0;
        }

        input = input_allocate_device();
        if (!input)
                return -ENOMEM;

        input_set_drvdata(input, steam);
        input->dev.parent = &hdev->dev;
        input->open = steam_input_open;
        input->close = steam_input_close;

        input->name = (steam->quirks & STEAM_QUIRK_WIRELESS) ? "Wireless Steam Controller" :
                (steam->quirks & STEAM_QUIRK_DECK) ? "Steam Deck" :
                "Steam Controller";
        input->phys = hdev->phys;
        input->uniq = steam->serial_no;
        input->id.bustype = hdev->bus;
        input->id.vendor = hdev->vendor;
        input->id.product = hdev->product;
        input->id.version = hdev->version;

        input_set_capability(input, EV_KEY, BTN_TR2);
        input_set_capability(input, EV_KEY, BTN_TL2);
        input_set_capability(input, EV_KEY, BTN_TR);
        input_set_capability(input, EV_KEY, BTN_TL);
        input_set_capability(input, EV_KEY, BTN_Y);
        input_set_capability(input, EV_KEY, BTN_B);
        input_set_capability(input, EV_KEY, BTN_X);
        input_set_capability(input, EV_KEY, BTN_A);
        input_set_capability(input, EV_KEY, BTN_DPAD_UP);
        input_set_capability(input, EV_KEY, BTN_DPAD_RIGHT);
        input_set_capability(input, EV_KEY, BTN_DPAD_LEFT);
        input_set_capability(input, EV_KEY, BTN_DPAD_DOWN);
        input_set_capability(input, EV_KEY, BTN_SELECT);
        input_set_capability(input, EV_KEY, BTN_MODE);
        input_set_capability(input, EV_KEY, BTN_START);
        input_set_capability(input, EV_KEY, BTN_THUMBR);
        input_set_capability(input, EV_KEY, BTN_THUMBL);
        input_set_capability(input, EV_KEY, BTN_THUMB);
        input_set_capability(input, EV_KEY, BTN_THUMB2);
        input_set_capability(input, EV_KEY, BTN_GRIPL);
        input_set_capability(input, EV_KEY, BTN_GRIPR);
        if (steam->quirks & STEAM_QUIRK_DECK) {
                input_set_capability(input, EV_KEY, BTN_BASE);
                input_set_capability(input, EV_KEY, BTN_GRIPL2);
                input_set_capability(input, EV_KEY, BTN_GRIPR2);
        }

        input_set_abs_params(input, ABS_X, -32767, 32767, 0, 0);
        input_set_abs_params(input, ABS_Y, -32767, 32767, 0, 0);

        input_set_abs_params(input, ABS_HAT0X, -32767, 32767,
                        STEAM_PAD_FUZZ, 0);
        input_set_abs_params(input, ABS_HAT0Y, -32767, 32767,
                        STEAM_PAD_FUZZ, 0);

        if (steam->quirks & STEAM_QUIRK_DECK) {
                input_set_abs_params(input, ABS_HAT2Y, 0, 32767, 0, 0);
                input_set_abs_params(input, ABS_HAT2X, 0, 32767, 0, 0);

                input_set_abs_params(input, ABS_RX, -32767, 32767, 0, 0);
                input_set_abs_params(input, ABS_RY, -32767, 32767, 0, 0);

                input_set_abs_params(input, ABS_HAT1X, -32767, 32767,
                                STEAM_PAD_FUZZ, 0);
                input_set_abs_params(input, ABS_HAT1Y, -32767, 32767,
                                STEAM_PAD_FUZZ, 0);

                input_abs_set_res(input, ABS_X, STEAM_DECK_JOYSTICK_RESOLUTION);
                input_abs_set_res(input, ABS_Y, STEAM_DECK_JOYSTICK_RESOLUTION);
                input_abs_set_res(input, ABS_RX, STEAM_DECK_JOYSTICK_RESOLUTION);
                input_abs_set_res(input, ABS_RY, STEAM_DECK_JOYSTICK_RESOLUTION);
                input_abs_set_res(input, ABS_HAT1X, STEAM_PAD_RESOLUTION);
                input_abs_set_res(input, ABS_HAT1Y, STEAM_PAD_RESOLUTION);
                input_abs_set_res(input, ABS_HAT2Y, STEAM_DECK_TRIGGER_RESOLUTION);
                input_abs_set_res(input, ABS_HAT2X, STEAM_DECK_TRIGGER_RESOLUTION);
        } else {
                input_set_abs_params(input, ABS_HAT2Y, 0, 255, 0, 0);
                input_set_abs_params(input, ABS_HAT2X, 0, 255, 0, 0);

                input_set_abs_params(input, ABS_RX, -32767, 32767,
                                STEAM_PAD_FUZZ, 0);
                input_set_abs_params(input, ABS_RY, -32767, 32767,
                                STEAM_PAD_FUZZ, 0);

                input_abs_set_res(input, ABS_X, STEAM_JOYSTICK_RESOLUTION);
                input_abs_set_res(input, ABS_Y, STEAM_JOYSTICK_RESOLUTION);
                input_abs_set_res(input, ABS_RX, STEAM_PAD_RESOLUTION);
                input_abs_set_res(input, ABS_RY, STEAM_PAD_RESOLUTION);
                input_abs_set_res(input, ABS_HAT2Y, STEAM_TRIGGER_RESOLUTION);
                input_abs_set_res(input, ABS_HAT2X, STEAM_TRIGGER_RESOLUTION);
        }
        input_abs_set_res(input, ABS_HAT0X, STEAM_PAD_RESOLUTION);
        input_abs_set_res(input, ABS_HAT0Y, STEAM_PAD_RESOLUTION);

#ifdef CONFIG_STEAM_FF
        if (steam->quirks & STEAM_QUIRK_DECK) {
                input_set_capability(input, EV_FF, FF_RUMBLE);
                ret = input_ff_create_memless(input, NULL, steam_play_effect);
                if (ret)
                        goto input_register_fail;
        }
#endif

        ret = input_register_device(input);
        if (ret)
                goto input_register_fail;

        rcu_assign_pointer(steam->input, input);
        return 0;

input_register_fail:
        input_free_device(input);
        return ret;
}

static int steam_sensors_register(struct steam_device *steam)
{
        struct hid_device *hdev = steam->hdev;
        struct input_dev *sensors;
        int ret;

        if (!(steam->quirks & STEAM_QUIRK_DECK))
                return 0;

        rcu_read_lock();
        sensors = rcu_dereference(steam->sensors);
        rcu_read_unlock();
        if (sensors) {
                dbg_hid("%s: already connected\n", __func__);
                return 0;
        }

        sensors = input_allocate_device();
        if (!sensors)
                return -ENOMEM;

        input_set_drvdata(sensors, steam);
        sensors->dev.parent = &hdev->dev;

        sensors->name = "Steam Deck Motion Sensors";
        sensors->phys = hdev->phys;
        sensors->uniq = steam->serial_no;
        sensors->id.bustype = hdev->bus;
        sensors->id.vendor = hdev->vendor;
        sensors->id.product = hdev->product;
        sensors->id.version = hdev->version;

        __set_bit(INPUT_PROP_ACCELEROMETER, sensors->propbit);
        __set_bit(EV_MSC, sensors->evbit);
        __set_bit(MSC_TIMESTAMP, sensors->mscbit);

        input_set_abs_params(sensors, ABS_X, -STEAM_DECK_ACCEL_RANGE,
                        STEAM_DECK_ACCEL_RANGE, STEAM_DECK_ACCEL_FUZZ, 0);
        input_set_abs_params(sensors, ABS_Y, -STEAM_DECK_ACCEL_RANGE,
                        STEAM_DECK_ACCEL_RANGE, STEAM_DECK_ACCEL_FUZZ, 0);
        input_set_abs_params(sensors, ABS_Z, -STEAM_DECK_ACCEL_RANGE,
                        STEAM_DECK_ACCEL_RANGE, STEAM_DECK_ACCEL_FUZZ, 0);
        input_abs_set_res(sensors, ABS_X, STEAM_DECK_ACCEL_RES_PER_G);
        input_abs_set_res(sensors, ABS_Y, STEAM_DECK_ACCEL_RES_PER_G);
        input_abs_set_res(sensors, ABS_Z, STEAM_DECK_ACCEL_RES_PER_G);

        input_set_abs_params(sensors, ABS_RX, -STEAM_DECK_GYRO_RANGE,
                        STEAM_DECK_GYRO_RANGE, STEAM_DECK_GYRO_FUZZ, 0);
        input_set_abs_params(sensors, ABS_RY, -STEAM_DECK_GYRO_RANGE,
                        STEAM_DECK_GYRO_RANGE, STEAM_DECK_GYRO_FUZZ, 0);
        input_set_abs_params(sensors, ABS_RZ, -STEAM_DECK_GYRO_RANGE,
                        STEAM_DECK_GYRO_RANGE, STEAM_DECK_GYRO_FUZZ, 0);
        input_abs_set_res(sensors, ABS_RX, STEAM_DECK_GYRO_RES_PER_DPS);
        input_abs_set_res(sensors, ABS_RY, STEAM_DECK_GYRO_RES_PER_DPS);
        input_abs_set_res(sensors, ABS_RZ, STEAM_DECK_GYRO_RES_PER_DPS);

        ret = input_register_device(sensors);
        if (ret)
                goto sensors_register_fail;

        rcu_assign_pointer(steam->sensors, sensors);
        return 0;

sensors_register_fail:
        input_free_device(sensors);
        return ret;
}

static void steam_input_unregister(struct steam_device *steam)
{
        struct input_dev *input;
        rcu_read_lock();
        input = rcu_dereference(steam->input);
        rcu_read_unlock();
        if (!input)
                return;
        RCU_INIT_POINTER(steam->input, NULL);
        synchronize_rcu();
        input_unregister_device(input);
}

static void steam_sensors_unregister(struct steam_device *steam)
{
        struct input_dev *sensors;

        if (!(steam->quirks & STEAM_QUIRK_DECK))
                return;

        rcu_read_lock();
        sensors = rcu_dereference(steam->sensors);
        rcu_read_unlock();

        if (!sensors)
                return;
        RCU_INIT_POINTER(steam->sensors, NULL);
        synchronize_rcu();
        input_unregister_device(sensors);
}

static void steam_battery_unregister(struct steam_device *steam)
{
        struct power_supply *battery;

        rcu_read_lock();
        battery = rcu_dereference(steam->battery);
        rcu_read_unlock();

        if (!battery)
                return;
        RCU_INIT_POINTER(steam->battery, NULL);
        synchronize_rcu();
        power_supply_unregister(battery);
}

static int steam_register(struct steam_device *steam)
{
        int ret;
        unsigned long client_opened;
        unsigned long flags;

        /*
         * This function can be called several times in a row with the
         * wireless adaptor, without steam_unregister() between them, because
         * another client send a get_connection_status command, for example.
         * The battery and serial number are set just once per device.
         */
        if (!steam->serial_no[0]) {
                /*
                 * Unlikely, but getting the serial could fail, and it is not so
                 * important, so make up a serial number and go on.
                 */
                if (steam_get_serial(steam) < 0)
                        strscpy(steam->serial_no, "XXXXXXXXXX",
                                        sizeof(steam->serial_no));

                hid_info(steam->hdev, "Steam Controller '%s' connected",
                                steam->serial_no);

                /* ignore battery errors, we can live without it */
                if (steam->quirks & STEAM_QUIRK_WIRELESS)
                        steam_battery_register(steam);

                mutex_lock(&steam_devices_lock);
                if (list_empty(&steam->list))
                        list_add(&steam->list, &steam_devices);
                mutex_unlock(&steam_devices_lock);
        }

        spin_lock_irqsave(&steam->lock, flags);
        client_opened = steam->client_opened;
        spin_unlock_irqrestore(&steam->lock, flags);

        if (!client_opened) {
                steam_set_lizard_mode(steam, lizard_mode);
                ret = steam_input_register(steam);
                if (ret != 0)
                        goto steam_register_input_fail;
                ret = steam_sensors_register(steam);
                if (ret != 0)
                        goto steam_register_sensors_fail;
        }
        return 0;

steam_register_sensors_fail:
        steam_input_unregister(steam);
steam_register_input_fail:
        return ret;
}

static void steam_unregister(struct steam_device *steam)
{
        steam_battery_unregister(steam);
        steam_sensors_unregister(steam);
        steam_input_unregister(steam);
        if (steam->serial_no[0]) {
                hid_info(steam->hdev, "Steam Controller '%s' disconnected",
                                steam->serial_no);
                mutex_lock(&steam_devices_lock);
                list_del_init(&steam->list);
                mutex_unlock(&steam_devices_lock);
                steam->serial_no[0] = 0;
        }
}

static void steam_work_connect_cb(struct work_struct *work)
{
        struct steam_device *steam = container_of(work, struct steam_device,
                                                        work_connect);
        unsigned long flags;
        bool connected;
        int ret;

        spin_lock_irqsave(&steam->lock, flags);
        connected = steam->connected;
        spin_unlock_irqrestore(&steam->lock, flags);

        if (connected) {
                ret = steam_register(steam);
                if (ret) {
                        hid_err(steam->hdev,
                                "%s:steam_register failed with error %d\n",
                                __func__, ret);
                }
        } else {
                steam_unregister(steam);
        }
}

static void steam_mode_switch_cb(struct work_struct *work)
{
        struct steam_device *steam = container_of(to_delayed_work(work),
                                                        struct steam_device, mode_switch);
        unsigned long flags;
        bool client_opened;
        if (!lizard_mode)
                return;

        steam->gamepad_mode = !steam->gamepad_mode;
        if (steam->gamepad_mode)
                steam_set_lizard_mode(steam, false);
        else {
                spin_lock_irqsave(&steam->lock, flags);
                client_opened = steam->client_opened;
                spin_unlock_irqrestore(&steam->lock, flags);
                if (!client_opened)
                        steam_set_lizard_mode(steam, lizard_mode);
        }

        steam_haptic_pulse(steam, STEAM_PAD_RIGHT, 0x190, 0, 1, 0);
        if (steam->gamepad_mode) {
                steam_haptic_pulse(steam, STEAM_PAD_LEFT, 0x14D, 0x14D, 0x2D, 0);
        } else {
                steam_haptic_pulse(steam, STEAM_PAD_LEFT, 0x1F4, 0x1F4, 0x1E, 0);
        }
}

static void steam_work_unregister_cb(struct work_struct *work)
{
        struct steam_device *steam = container_of(work, struct steam_device,
                                                        unregister_work);
        unsigned long flags;
        bool connected;
        bool opened;

        spin_lock_irqsave(&steam->lock, flags);
        opened = steam->client_opened;
        connected = steam->connected;
        spin_unlock_irqrestore(&steam->lock, flags);

        if (connected) {
                if (opened) {
                        steam_sensors_unregister(steam);
                        steam_input_unregister(steam);
                } else {
                        steam_set_lizard_mode(steam, lizard_mode);
                        steam_input_register(steam);
                        steam_sensors_register(steam);
                }
        }
}

static bool steam_is_valve_interface(struct hid_device *hdev)
{
        struct hid_report_enum *rep_enum;

        /*
         * The wired device creates 3 interfaces:
         *  0: emulated mouse.
         *  1: emulated keyboard.
         *  2: the real game pad.
         * The wireless device creates 5 interfaces:
         *  0: emulated keyboard.
         *  1-4: slots where up to 4 real game pads will be connected to.
         * We know which one is the real gamepad interface because they are the
         * only ones with a feature report.
         */
        rep_enum = &hdev->report_enum[HID_FEATURE_REPORT];
        return !list_empty(&rep_enum->report_list);
}

static int steam_client_ll_parse(struct hid_device *hdev)
{
        struct steam_device *steam = hdev->driver_data;

        return hid_parse_report(hdev, steam->hdev->dev_rdesc,
                        steam->hdev->dev_rsize);
}

static int steam_client_ll_start(struct hid_device *hdev)
{
        return 0;
}

static void steam_client_ll_stop(struct hid_device *hdev)
{
}

static int steam_client_ll_open(struct hid_device *hdev)
{
        struct steam_device *steam = hdev->driver_data;
        unsigned long flags;

        spin_lock_irqsave(&steam->lock, flags);
        steam->client_opened++;
        spin_unlock_irqrestore(&steam->lock, flags);

        schedule_work(&steam->unregister_work);

        return 0;
}

static void steam_client_ll_close(struct hid_device *hdev)
{
        struct steam_device *steam = hdev->driver_data;

        unsigned long flags;

        spin_lock_irqsave(&steam->lock, flags);
        steam->client_opened--;
        spin_unlock_irqrestore(&steam->lock, flags);

        schedule_work(&steam->unregister_work);
}

static int steam_client_ll_raw_request(struct hid_device *hdev,
                                unsigned char reportnum, u8 *buf,
                                size_t count, unsigned char report_type,
                                int reqtype)
{
        struct steam_device *steam = hdev->driver_data;

        return hid_hw_raw_request(steam->hdev, reportnum, buf, count,
                        report_type, reqtype);
}

static const struct hid_ll_driver steam_client_ll_driver = {
        .parse = steam_client_ll_parse,
        .start = steam_client_ll_start,
        .stop = steam_client_ll_stop,
        .open = steam_client_ll_open,
        .close = steam_client_ll_close,
        .raw_request = steam_client_ll_raw_request,
};

static struct hid_device *steam_create_client_hid(struct hid_device *hdev)
{
        struct hid_device *client_hdev;

        client_hdev = hid_allocate_device();
        if (IS_ERR(client_hdev))
                return client_hdev;

        client_hdev->ll_driver = &steam_client_ll_driver;
        client_hdev->dev.parent = hdev->dev.parent;
        client_hdev->bus = hdev->bus;
        client_hdev->vendor = hdev->vendor;
        client_hdev->product = hdev->product;
        client_hdev->version = hdev->version;
        client_hdev->type = hdev->type;
        client_hdev->country = hdev->country;
        strscpy(client_hdev->name, hdev->name,
                        sizeof(client_hdev->name));
        strscpy(client_hdev->phys, hdev->phys,
                        sizeof(client_hdev->phys));
        /*
         * Since we use the same device info than the real interface to
         * trick userspace, we will be calling steam_probe recursively.
         * We need to recognize the client interface somehow.
         */
        client_hdev->group = HID_GROUP_STEAM;
        return client_hdev;
}

static int steam_probe(struct hid_device *hdev,
                                const struct hid_device_id *id)
{
        struct steam_device *steam;
        int ret;

        ret = hid_parse(hdev);
        if (ret) {
                hid_err(hdev,
                        "%s:parse of hid interface failed\n", __func__);
                return ret;
        }

        /*
         * The virtual client_dev is only used for hidraw.
         * Also avoid the recursive probe.
         */
        if (hdev->group == HID_GROUP_STEAM)
                return hid_hw_start(hdev, HID_CONNECT_HIDRAW);
        /*
         * The non-valve interfaces (mouse and keyboard emulation) are
         * connected without changes.
         */
        if (!steam_is_valve_interface(hdev))
                return hid_hw_start(hdev, HID_CONNECT_DEFAULT);

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

        steam->hdev = hdev;
        hid_set_drvdata(hdev, steam);
        spin_lock_init(&steam->lock);
        mutex_init(&steam->report_mutex);
        steam->quirks = id->driver_data;
        INIT_WORK(&steam->work_connect, steam_work_connect_cb);
        INIT_DELAYED_WORK(&steam->mode_switch, steam_mode_switch_cb);
        INIT_LIST_HEAD(&steam->list);
        INIT_WORK(&steam->rumble_work, steam_haptic_rumble_cb);
        steam->sensor_timestamp_us = 0;
        INIT_WORK(&steam->unregister_work, steam_work_unregister_cb);

        /*
         * With the real steam controller interface, do not connect hidraw.
         * Instead, create the client_hid and connect that.
         */
        ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_HIDRAW);
        if (ret)
                goto err_cancel_work;

        ret = hid_hw_open(hdev);
        if (ret) {
                hid_err(hdev,
                        "%s:hid_hw_open\n",
                        __func__);
                goto err_hw_stop;
        }

        if (steam->quirks & STEAM_QUIRK_WIRELESS) {
                hid_info(hdev, "Steam wireless receiver connected");
                /* If using a wireless adaptor ask for connection status */
                steam->connected = false;
                steam_request_conn_status(steam);
        } else {
                /* A wired connection is always present */
                steam->connected = true;
                ret = steam_register(steam);
                if (ret) {
                        hid_err(hdev,
                                "%s:steam_register failed with error %d\n",
                                __func__, ret);
                        goto err_hw_close;
                }
        }

        steam->client_hdev = steam_create_client_hid(hdev);
        if (IS_ERR(steam->client_hdev)) {
                ret = PTR_ERR(steam->client_hdev);
                goto err_steam_unregister;
        }
        steam->client_hdev->driver_data = steam;

        ret = hid_add_device(steam->client_hdev);
        if (ret)
                goto err_destroy;

        return 0;

err_destroy:
        hid_destroy_device(steam->client_hdev);
err_steam_unregister:
        if (steam->connected)
                steam_unregister(steam);
err_hw_close:
        hid_hw_close(hdev);
err_hw_stop:
        hid_hw_stop(hdev);
err_cancel_work:
        cancel_work_sync(&steam->work_connect);
        cancel_delayed_work_sync(&steam->mode_switch);
        cancel_work_sync(&steam->rumble_work);
        cancel_work_sync(&steam->unregister_work);

        return ret;
}

static void steam_remove(struct hid_device *hdev)
{
        struct steam_device *steam = hid_get_drvdata(hdev);

        if (!steam || hdev->group == HID_GROUP_STEAM) {
                hid_hw_stop(hdev);
                return;
        }

        hid_destroy_device(steam->client_hdev);
        cancel_delayed_work_sync(&steam->mode_switch);
        cancel_work_sync(&steam->work_connect);
        cancel_work_sync(&steam->rumble_work);
        cancel_work_sync(&steam->unregister_work);
        steam->client_hdev = NULL;
        steam->client_opened = 0;
        if (steam->quirks & STEAM_QUIRK_WIRELESS) {
                hid_info(hdev, "Steam wireless receiver disconnected");
        }
        hid_hw_close(hdev);
        hid_hw_stop(hdev);
        steam_unregister(steam);
}

static void steam_do_connect_event(struct steam_device *steam, bool connected)
{
        unsigned long flags;
        bool changed;

        spin_lock_irqsave(&steam->lock, flags);
        changed = steam->connected != connected;
        steam->connected = connected;
        spin_unlock_irqrestore(&steam->lock, flags);

        if (changed && schedule_work(&steam->work_connect) == 0)
                dbg_hid("%s: connected=%d event already queued\n",
                                __func__, connected);
}

/*
 * Some input data in the protocol has the opposite sign.
 * Clamp the values to 32767..-32767 so that the range is
 * symmetrical and can be negated safely.
 */
static inline s16 steam_le16(u8 *data)
{
        s16 x = (s16) le16_to_cpup((__le16 *)data);

        return x == -32768 ? -32767 : x;
}

/*
 * The size for this message payload is 60.
 * The known values are:
 *  (* values are not sent through wireless)
 *  (* accelerator/gyro is disabled by default)
 *  Offset| Type  | Mapped to |Meaning
 * -------+-------+-----------+--------------------------
 *  4-7   | u32   | --        | sequence number
 *  8-10  | 24bit | see below | buttons
 *  11    | u8    | ABS_HAT2Y | left trigger
 *  12    | u8    | ABS_HAT2X | right trigger
 *  13-15 | --    | --        | always 0
 *  16-17 | s16   | ABS_X/ABS_HAT0X     | X value
 *  18-19 | s16   | ABS_Y/ABS_HAT0Y     | Y value
 *  20-21 | s16   | ABS_RX    | right-pad X value
 *  22-23 | s16   | ABS_RY    | right-pad Y value
 *  24-25 | s16   | --        | * left trigger
 *  26-27 | s16   | --        | * right trigger
 *  28-29 | s16   | --        | * accelerometer X value
 *  30-31 | s16   | --        | * accelerometer Y value
 *  32-33 | s16   | --        | * accelerometer Z value
 *  34-35 | s16   | --        | gyro X value
 *  36-36 | s16   | --        | gyro Y value
 *  38-39 | s16   | --        | gyro Z value
 *  40-41 | s16   | --        | quaternion W value
 *  42-43 | s16   | --        | quaternion X value
 *  44-45 | s16   | --        | quaternion Y value
 *  46-47 | s16   | --        | quaternion Z value
 *  48-49 | --    | --        | always 0
 *  50-51 | s16   | --        | * left trigger (uncalibrated)
 *  52-53 | s16   | --        | * right trigger (uncalibrated)
 *  54-55 | s16   | --        | * joystick X value (uncalibrated)
 *  56-57 | s16   | --        | * joystick Y value (uncalibrated)
 *  58-59 | s16   | --        | * left-pad X value
 *  60-61 | s16   | --        | * left-pad Y value
 *  62-63 | u16   | --        | * battery voltage
 *
 * The buttons are:
 *  Bit  | Mapped to  | Description
 * ------+------------+--------------------------------
 *  8.0  | BTN_TR2    | right trigger fully pressed
 *  8.1  | BTN_TL2    | left trigger fully pressed
 *  8.2  | BTN_TR     | right shoulder
 *  8.3  | BTN_TL     | left shoulder
 *  8.4  | BTN_Y      | button Y
 *  8.5  | BTN_B      | button B
 *  8.6  | BTN_X      | button X
 *  8.7  | BTN_A      | button A
 *  9.0  | BTN_DPAD_UP    | left-pad up
 *  9.1  | BTN_DPAD_RIGHT | left-pad right
 *  9.2  | BTN_DPAD_LEFT  | left-pad left
 *  9.3  | BTN_DPAD_DOWN  | left-pad down
 *  9.4  | BTN_SELECT | menu left
 *  9.5  | BTN_MODE   | steam logo
 *  9.6  | BTN_START  | menu right
 *  9.7  | BTN_GRIPL  | left back lever
 * 10.0  | BTN_GRIPR  | right back lever
 * 10.1  | --         | left-pad clicked
 * 10.2  | BTN_THUMBR | right-pad clicked
 * 10.3  | BTN_THUMB  | left-pad touched (but see explanation below)
 * 10.4  | BTN_THUMB2 | right-pad touched
 * 10.5  | --         | unknown
 * 10.6  | BTN_THUMBL | joystick clicked
 * 10.7  | --         | lpad_and_joy
 */

static void steam_do_input_event(struct steam_device *steam,
                struct input_dev *input, u8 *data)
{
        /* 24 bits of buttons */
        u8 b8, b9, b10;
        s16 x, y;
        bool lpad_touched, lpad_and_joy;

        b8 = data[8];
        b9 = data[9];
        b10 = data[10];

        input_report_abs(input, ABS_HAT2Y, data[11]);
        input_report_abs(input, ABS_HAT2X, data[12]);

        /*
         * These two bits tells how to interpret the values X and Y.
         * lpad_and_joy tells that the joystick and the lpad are used at the
         * same time.
         * lpad_touched tells whether X/Y are to be read as lpad coord or
         * joystick values.
         * (lpad_touched || lpad_and_joy) tells if the lpad is really touched.
         */
        lpad_touched = b10 & BIT(3);
        lpad_and_joy = b10 & BIT(7);
        x = steam_le16(data + 16);
        y = -steam_le16(data + 18);

        input_report_abs(input, lpad_touched ? ABS_HAT0X : ABS_X, x);
        input_report_abs(input, lpad_touched ? ABS_HAT0Y : ABS_Y, y);
        /* Check if joystick is centered */
        if (lpad_touched && !lpad_and_joy) {
                input_report_abs(input, ABS_X, 0);
                input_report_abs(input, ABS_Y, 0);
        }
        /* Check if lpad is untouched */
        if (!(lpad_touched || lpad_and_joy)) {
                input_report_abs(input, ABS_HAT0X, 0);
                input_report_abs(input, ABS_HAT0Y, 0);
        }

        input_report_abs(input, ABS_RX, steam_le16(data + 20));
        input_report_abs(input, ABS_RY, -steam_le16(data + 22));

        input_event(input, EV_KEY, BTN_TR2, !!(b8 & BIT(0)));
        input_event(input, EV_KEY, BTN_TL2, !!(b8 & BIT(1)));
        input_event(input, EV_KEY, BTN_TR, !!(b8 & BIT(2)));
        input_event(input, EV_KEY, BTN_TL, !!(b8 & BIT(3)));
        input_event(input, EV_KEY, BTN_Y, !!(b8 & BIT(4)));
        input_event(input, EV_KEY, BTN_B, !!(b8 & BIT(5)));
        input_event(input, EV_KEY, BTN_X, !!(b8 & BIT(6)));
        input_event(input, EV_KEY, BTN_A, !!(b8 & BIT(7)));
        input_event(input, EV_KEY, BTN_SELECT, !!(b9 & BIT(4)));
        input_event(input, EV_KEY, BTN_MODE, !!(b9 & BIT(5)));
        input_event(input, EV_KEY, BTN_START, !!(b9 & BIT(6)));
        input_event(input, EV_KEY, BTN_GRIPL, !!(b9 & BIT(7)));
        input_event(input, EV_KEY, BTN_GRIPR, !!(b10 & BIT(0)));
        input_event(input, EV_KEY, BTN_THUMBR, !!(b10 & BIT(2)));
        input_event(input, EV_KEY, BTN_THUMBL, !!(b10 & BIT(6)));
        input_event(input, EV_KEY, BTN_THUMB, lpad_touched || lpad_and_joy);
        input_event(input, EV_KEY, BTN_THUMB2, !!(b10 & BIT(4)));
        input_event(input, EV_KEY, BTN_DPAD_UP, !!(b9 & BIT(0)));
        input_event(input, EV_KEY, BTN_DPAD_RIGHT, !!(b9 & BIT(1)));
        input_event(input, EV_KEY, BTN_DPAD_LEFT, !!(b9 & BIT(2)));
        input_event(input, EV_KEY, BTN_DPAD_DOWN, !!(b9 & BIT(3)));

        input_sync(input);
}

/*
 * The size for this message payload is 56.
 * The known values are:
 *  Offset| Type  | Mapped to |Meaning
 * -------+-------+-----------+--------------------------
 *  4-7   | u32   | --        | sequence number
 *  8-15  | u64   | see below | buttons
 *  16-17 | s16   | ABS_HAT0X | left-pad X value
 *  18-19 | s16   | ABS_HAT0Y | left-pad Y value
 *  20-21 | s16   | ABS_HAT1X | right-pad X value
 *  22-23 | s16   | ABS_HAT1Y | right-pad Y value
 *  24-25 | s16   | IMU ABS_X | accelerometer X value
 *  26-27 | s16   | IMU ABS_Z | accelerometer Y value
 *  28-29 | s16   | IMU ABS_Y | accelerometer Z value
 *  30-31 | s16   | IMU ABS_RX | gyro X value
 *  32-33 | s16   | IMU ABS_RZ | gyro Y value
 *  34-35 | s16   | IMU ABS_RY | gyro Z value
 *  36-37 | s16   | --        | quaternion W value
 *  38-39 | s16   | --        | quaternion X value
 *  40-41 | s16   | --        | quaternion Y value
 *  42-43 | s16   | --        | quaternion Z value
 *  44-45 | u16   | ABS_HAT2Y | left trigger (uncalibrated)
 *  46-47 | u16   | ABS_HAT2X | right trigger (uncalibrated)
 *  48-49 | s16   | ABS_X     | left joystick X
 *  50-51 | s16   | ABS_Y     | left joystick Y
 *  52-53 | s16   | ABS_RX    | right joystick X
 *  54-55 | s16   | ABS_RY    | right joystick Y
 *  56-57 | u16   | --        | left pad pressure
 *  58-59 | u16   | --        | right pad pressure
 *
 * The buttons are:
 *  Bit  | Mapped to  | Description
 * ------+------------+--------------------------------
 *  8.0  | BTN_TR2    | right trigger fully pressed
 *  8.1  | BTN_TL2    | left trigger fully pressed
 *  8.2  | BTN_TR     | right shoulder
 *  8.3  | BTN_TL     | left shoulder
 *  8.4  | BTN_Y      | button Y
 *  8.5  | BTN_B      | button B
 *  8.6  | BTN_X      | button X
 *  8.7  | BTN_A      | button A
 *  9.0  | BTN_DPAD_UP    | left-pad up
 *  9.1  | BTN_DPAD_RIGHT | left-pad right
 *  9.2  | BTN_DPAD_LEFT  | left-pad left
 *  9.3  | BTN_DPAD_DOWN  | left-pad down
 *  9.4  | BTN_SELECT | menu left
 *  9.5  | BTN_MODE   | steam logo
 *  9.6  | BTN_START  | menu right
 *  9.7  | BTN_GRIPL2 | left bottom grip button
 *  10.0 | BTN_GRIPR2 | right bottom grip button
 *  10.1 | BTN_THUMB  | left pad pressed
 *  10.2 | BTN_THUMB2 | right pad pressed
 *  10.3 | --         | left pad touched
 *  10.4 | --         | right pad touched
 *  10.5 | --         | unknown
 *  10.6 | BTN_THUMBL | left joystick clicked
 *  10.7 | --         | unknown
 *  11.0 | --         | unknown
 *  11.1 | --         | unknown
 *  11.2 | BTN_THUMBR | right joystick clicked
 *  11.3 | --         | unknown
 *  11.4 | --         | unknown
 *  11.5 | --         | unknown
 *  11.6 | --         | unknown
 *  11.7 | --         | unknown
 *  12.0 | --         | unknown
 *  12.1 | --         | unknown
 *  12.2 | --         | unknown
 *  12.3 | --         | unknown
 *  12.4 | --         | unknown
 *  12.5 | --         | unknown
 *  12.6 | --         | unknown
 *  12.7 | --         | unknown
 *  13.0 | --         | unknown
 *  13.1 | BTN_GRIPL  | left top grip button
 *  13.2 | BTN_GRIPR  | right top grip button
 *  13.3 | --         | unknown
 *  13.4 | --         | unknown
 *  13.5 | --         | unknown
 *  13.6 | --         | left joystick touched
 *  13.7 | --         | right joystick touched
 *  14.0 | --         | unknown
 *  14.1 | --         | unknown
 *  14.2 | BTN_BASE   | quick access button
 *  14.3 | --         | unknown
 *  14.4 | --         | unknown
 *  14.5 | --         | unknown
 *  14.6 | --         | unknown
 *  14.7 | --         | unknown
 *  15.0 | --         | unknown
 *  15.1 | --         | unknown
 *  15.2 | --         | unknown
 *  15.3 | --         | unknown
 *  15.4 | --         | unknown
 *  15.5 | --         | unknown
 *  15.6 | --         | unknown
 *  15.7 | --         | unknown
 */
static void steam_do_deck_input_event(struct steam_device *steam,
                struct input_dev *input, u8 *data)
{
        u8 b8, b9, b10, b11, b13, b14;
        bool lpad_touched, rpad_touched;

        b8 = data[8];
        b9 = data[9];
        b10 = data[10];
        b11 = data[11];
        b13 = data[13];
        b14 = data[14];

        if (!(b9 & BIT(6)) && steam->did_mode_switch) {
                steam->did_mode_switch = false;
                cancel_delayed_work(&steam->mode_switch);
        } else if (!steam->client_opened && (b9 & BIT(6)) && !steam->did_mode_switch) {
                steam->did_mode_switch = true;
                schedule_delayed_work(&steam->mode_switch, 45 * HZ / 100);
        }

        if (!steam->gamepad_mode && lizard_mode)
                return;

        lpad_touched = b10 & BIT(3);
        rpad_touched = b10 & BIT(4);

        if (lpad_touched) {
                input_report_abs(input, ABS_HAT0X, steam_le16(data + 16));
                input_report_abs(input, ABS_HAT0Y, steam_le16(data + 18));
        } else {
                input_report_abs(input, ABS_HAT0X, 0);
                input_report_abs(input, ABS_HAT0Y, 0);
        }

        if (rpad_touched) {
                input_report_abs(input, ABS_HAT1X, steam_le16(data + 20));
                input_report_abs(input, ABS_HAT1Y, steam_le16(data + 22));
        } else {
                input_report_abs(input, ABS_HAT1X, 0);
                input_report_abs(input, ABS_HAT1Y, 0);
        }

        input_report_abs(input, ABS_X, steam_le16(data + 48));
        input_report_abs(input, ABS_Y, -steam_le16(data + 50));
        input_report_abs(input, ABS_RX, steam_le16(data + 52));
        input_report_abs(input, ABS_RY, -steam_le16(data + 54));

        input_report_abs(input, ABS_HAT2Y, steam_le16(data + 44));
        input_report_abs(input, ABS_HAT2X, steam_le16(data + 46));

        input_event(input, EV_KEY, BTN_TR2, !!(b8 & BIT(0)));
        input_event(input, EV_KEY, BTN_TL2, !!(b8 & BIT(1)));
        input_event(input, EV_KEY, BTN_TR, !!(b8 & BIT(2)));
        input_event(input, EV_KEY, BTN_TL, !!(b8 & BIT(3)));
        input_event(input, EV_KEY, BTN_Y, !!(b8 & BIT(4)));
        input_event(input, EV_KEY, BTN_B, !!(b8 & BIT(5)));
        input_event(input, EV_KEY, BTN_X, !!(b8 & BIT(6)));
        input_event(input, EV_KEY, BTN_A, !!(b8 & BIT(7)));
        input_event(input, EV_KEY, BTN_SELECT, !!(b9 & BIT(4)));
        input_event(input, EV_KEY, BTN_MODE, !!(b9 & BIT(5)));
        input_event(input, EV_KEY, BTN_START, !!(b9 & BIT(6)));
        input_event(input, EV_KEY, BTN_GRIPL2, !!(b9 & BIT(7)));
        input_event(input, EV_KEY, BTN_GRIPR2, !!(b10 & BIT(0)));
        input_event(input, EV_KEY, BTN_THUMBL, !!(b10 & BIT(6)));
        input_event(input, EV_KEY, BTN_THUMBR, !!(b11 & BIT(2)));
        input_event(input, EV_KEY, BTN_DPAD_UP, !!(b9 & BIT(0)));
        input_event(input, EV_KEY, BTN_DPAD_RIGHT, !!(b9 & BIT(1)));
        input_event(input, EV_KEY, BTN_DPAD_LEFT, !!(b9 & BIT(2)));
        input_event(input, EV_KEY, BTN_DPAD_DOWN, !!(b9 & BIT(3)));
        input_event(input, EV_KEY, BTN_THUMB, !!(b10 & BIT(1)));
        input_event(input, EV_KEY, BTN_THUMB2, !!(b10 & BIT(2)));
        input_event(input, EV_KEY, BTN_GRIPL, !!(b13 & BIT(1)));
        input_event(input, EV_KEY, BTN_GRIPR, !!(b13 & BIT(2)));
        input_event(input, EV_KEY, BTN_BASE, !!(b14 & BIT(2)));

        input_sync(input);
}

static void steam_do_deck_sensors_event(struct steam_device *steam,
                struct input_dev *sensors, u8 *data)
{
        /*
         * The deck input report is received every 4 ms on average,
         * with a jitter of +/- 4 ms even though the USB descriptor claims
         * that it uses 1 kHz.
         * Since the HID report does not include a sensor timestamp,
         * use a fixed increment here.
         */
        steam->sensor_timestamp_us += 4000;

        if (!steam->gamepad_mode && lizard_mode)
                return;

        input_event(sensors, EV_MSC, MSC_TIMESTAMP, steam->sensor_timestamp_us);
        input_report_abs(sensors, ABS_X, steam_le16(data + 24));
        input_report_abs(sensors, ABS_Z, -steam_le16(data + 26));
        input_report_abs(sensors, ABS_Y, steam_le16(data + 28));
        input_report_abs(sensors, ABS_RX, steam_le16(data + 30));
        input_report_abs(sensors, ABS_RZ, -steam_le16(data + 32));
        input_report_abs(sensors, ABS_RY, steam_le16(data + 34));

        input_sync(sensors);
}

/*
 * The size for this message payload is 11.
 * The known values are:
 *  Offset| Type  | Meaning
 * -------+-------+---------------------------
 *  4-7   | u32   | sequence number
 *  8-11  | --    | always 0
 *  12-13 | u16   | voltage (mV)
 *  14    | u8    | battery percent
 */
static void steam_do_battery_event(struct steam_device *steam,
                struct power_supply *battery, u8 *data)
{
        unsigned long flags;

        s16 volts = steam_le16(data + 12);
        u8 batt = data[14];

        /* Creating the battery may have failed */
        rcu_read_lock();
        battery = rcu_dereference(steam->battery);
        if (likely(battery)) {
                spin_lock_irqsave(&steam->lock, flags);
                steam->voltage = volts;
                steam->battery_charge = batt;
                spin_unlock_irqrestore(&steam->lock, flags);
                power_supply_changed(battery);
        }
        rcu_read_unlock();
}

static int steam_raw_event(struct hid_device *hdev,
                        struct hid_report *report, u8 *data,
                        int size)
{
        struct steam_device *steam = hid_get_drvdata(hdev);
        struct input_dev *input;
        struct input_dev *sensors;
        struct power_supply *battery;

        if (!steam)
                return 0;

        if (steam->client_opened)
                hid_input_report(steam->client_hdev, HID_FEATURE_REPORT,
                                data, size, 0);
        /*
         * All messages are size=64, all values little-endian.
         * The format is:
         *  Offset| Meaning
         * -------+--------------------------------------------
         *  0-1   | always 0x01, 0x00, maybe protocol version?
         *  2     | type of message
         *  3     | length of the real payload (not checked)
         *  4-n   | payload data, depends on the type
         *
         * There are these known types of message:
         *  0x01: input data (60 bytes)
         *  0x03: wireless connect/disconnect (1 byte)
         *  0x04: battery status (11 bytes)
         *  0x09: Steam Deck input data (56 bytes)
         */

        if (size != 64 || data[0] != 1 || data[1] != 0)
                return 0;

        switch (data[2]) {
        case ID_CONTROLLER_STATE:
                if (steam->client_opened)
                        return 0;
                rcu_read_lock();
                input = rcu_dereference(steam->input);
                if (likely(input))
                        steam_do_input_event(steam, input, data);
                rcu_read_unlock();
                break;
        case ID_CONTROLLER_DECK_STATE:
                if (steam->client_opened)
                        return 0;
                rcu_read_lock();
                input = rcu_dereference(steam->input);
                if (likely(input))
                        steam_do_deck_input_event(steam, input, data);
                sensors = rcu_dereference(steam->sensors);
                if (likely(sensors))
                        steam_do_deck_sensors_event(steam, sensors, data);
                rcu_read_unlock();
                break;
        case ID_CONTROLLER_WIRELESS:
                /*
                 * The payload of this event is a single byte:
                 *  0x01: disconnected.
                 *  0x02: connected.
                 */
                switch (data[4]) {
                case 0x01:
                        steam_do_connect_event(steam, false);
                        break;
                case 0x02:
                        steam_do_connect_event(steam, true);
                        break;
                }
                break;
        case ID_CONTROLLER_STATUS:
                if (steam->quirks & STEAM_QUIRK_WIRELESS) {
                        rcu_read_lock();
                        battery = rcu_dereference(steam->battery);
                        if (likely(battery)) {
                                steam_do_battery_event(steam, battery, data);
                        } else {
                                dbg_hid(
                                        "%s: battery data without connect event\n",
                                        __func__);
                                steam_do_connect_event(steam, true);
                        }
                        rcu_read_unlock();
                }
                break;
        }
        return 0;
}

static int steam_param_set_lizard_mode(const char *val,
                                        const struct kernel_param *kp)
{
        struct steam_device *steam;
        int ret;

        ret = param_set_bool(val, kp);
        if (ret)
                return ret;

        mutex_lock(&steam_devices_lock);
        list_for_each_entry(steam, &steam_devices, list) {
                if (!steam->client_opened)
                        steam_set_lizard_mode(steam, lizard_mode);
        }
        mutex_unlock(&steam_devices_lock);
        return 0;
}

static const struct kernel_param_ops steam_lizard_mode_ops = {
        .set    = steam_param_set_lizard_mode,
        .get    = param_get_bool,
};

module_param_cb(lizard_mode, &steam_lizard_mode_ops, &lizard_mode, 0644);
MODULE_PARM_DESC(lizard_mode,
        "Enable mouse and keyboard emulation (lizard mode) when the gamepad is not in use");

static const struct hid_device_id steam_controllers[] = {
        { /* Wired Steam Controller */
          HID_USB_DEVICE(USB_VENDOR_ID_VALVE,
                USB_DEVICE_ID_STEAM_CONTROLLER)
        },
        { /* Wireless Steam Controller */
          HID_USB_DEVICE(USB_VENDOR_ID_VALVE,
                USB_DEVICE_ID_STEAM_CONTROLLER_WIRELESS),
          .driver_data = STEAM_QUIRK_WIRELESS
        },
        { /* Steam Deck */
          HID_USB_DEVICE(USB_VENDOR_ID_VALVE,
                USB_DEVICE_ID_STEAM_DECK),
          .driver_data = STEAM_QUIRK_DECK
        },
        {}
};

MODULE_DEVICE_TABLE(hid, steam_controllers);

static struct hid_driver steam_controller_driver = {
        .name = "hid-steam",
        .id_table = steam_controllers,
        .probe = steam_probe,
        .remove = steam_remove,
        .raw_event = steam_raw_event,
};

module_hid_driver(steam_controller_driver);