root/drivers/hid/hid-nvidia-shield.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
 *
 *  HID driver for NVIDIA SHIELD peripherals.
 */

#include <linux/hid.h>
#include <linux/idr.h>
#include <linux/input-event-codes.h>
#include <linux/input.h>
#include <linux/jiffies.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/power_supply.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/workqueue.h>

#include "hid-ids.h"

#define NOT_INIT_STR "NOT INITIALIZED"
#define android_map_key(c) hid_map_usage(hi, usage, bit, max, EV_KEY, (c))

enum {
        HID_USAGE_ANDROID_PLAYPAUSE_BTN = 0xcd, /* Double-tap volume slider */
        HID_USAGE_ANDROID_VOLUMEUP_BTN = 0xe9,
        HID_USAGE_ANDROID_VOLUMEDOWN_BTN = 0xea,
        HID_USAGE_ANDROID_SEARCH_BTN = 0x221, /* NVIDIA btn on Thunderstrike */
        HID_USAGE_ANDROID_HOME_BTN = 0x223,
        HID_USAGE_ANDROID_BACK_BTN = 0x224,
};

enum {
        SHIELD_FW_VERSION_INITIALIZED = 0,
        SHIELD_BOARD_INFO_INITIALIZED,
        SHIELD_BATTERY_STATS_INITIALIZED,
        SHIELD_CHARGER_STATE_INITIALIZED,
};

enum {
        THUNDERSTRIKE_FW_VERSION_UPDATE = 0,
        THUNDERSTRIKE_BOARD_INFO_UPDATE,
        THUNDERSTRIKE_HAPTICS_UPDATE,
        THUNDERSTRIKE_LED_UPDATE,
        THUNDERSTRIKE_POWER_SUPPLY_STATS_UPDATE,
};

enum {
        THUNDERSTRIKE_HOSTCMD_REPORT_SIZE = 33,
        THUNDERSTRIKE_HOSTCMD_REQ_REPORT_ID = 0x4,
        THUNDERSTRIKE_HOSTCMD_RESP_REPORT_ID = 0x3,
};

enum {
        THUNDERSTRIKE_HOSTCMD_ID_FW_VERSION = 1,
        THUNDERSTRIKE_HOSTCMD_ID_LED = 6,
        THUNDERSTRIKE_HOSTCMD_ID_BATTERY,
        THUNDERSTRIKE_HOSTCMD_ID_BOARD_INFO = 16,
        THUNDERSTRIKE_HOSTCMD_ID_USB_INIT = 53,
        THUNDERSTRIKE_HOSTCMD_ID_HAPTICS = 57,
        THUNDERSTRIKE_HOSTCMD_ID_CHARGER,
};

struct power_supply_dev {
        struct power_supply *psy;
        struct power_supply_desc desc;
};

struct thunderstrike_psy_prop_values {
        int voltage_min;
        int voltage_now;
        int voltage_avg;
        int voltage_boot;
        int capacity;
        int status;
        int charge_type;
        int temp;
};

static const enum power_supply_property thunderstrike_battery_props[] = {
        POWER_SUPPLY_PROP_STATUS,
        POWER_SUPPLY_PROP_CHARGE_TYPE,
        POWER_SUPPLY_PROP_PRESENT,
        POWER_SUPPLY_PROP_VOLTAGE_MIN,
        POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
        POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
        POWER_SUPPLY_PROP_VOLTAGE_NOW,
        POWER_SUPPLY_PROP_VOLTAGE_AVG,
        POWER_SUPPLY_PROP_VOLTAGE_BOOT,
        POWER_SUPPLY_PROP_CAPACITY,
        POWER_SUPPLY_PROP_SCOPE,
        POWER_SUPPLY_PROP_TEMP,
        POWER_SUPPLY_PROP_TEMP_MIN,
        POWER_SUPPLY_PROP_TEMP_MAX,
        POWER_SUPPLY_PROP_TEMP_ALERT_MIN,
        POWER_SUPPLY_PROP_TEMP_ALERT_MAX,
};

enum thunderstrike_led_state {
        THUNDERSTRIKE_LED_OFF = 1,
        THUNDERSTRIKE_LED_ON = 8,
} __packed;
static_assert(sizeof(enum thunderstrike_led_state) == 1);

struct thunderstrike_hostcmd_battery {
        __le16 voltage_avg;
        u8 reserved_at_10;
        __le16 thermistor;
        __le16 voltage_min;
        __le16 voltage_boot;
        __le16 voltage_now;
        u8 capacity;
} __packed;

enum thunderstrike_charger_type {
        THUNDERSTRIKE_CHARGER_TYPE_NONE = 0,
        THUNDERSTRIKE_CHARGER_TYPE_TRICKLE,
        THUNDERSTRIKE_CHARGER_TYPE_NORMAL,
} __packed;
static_assert(sizeof(enum thunderstrike_charger_type) == 1);

enum thunderstrike_charger_state {
        THUNDERSTRIKE_CHARGER_STATE_UNKNOWN = 0,
        THUNDERSTRIKE_CHARGER_STATE_DISABLED,
        THUNDERSTRIKE_CHARGER_STATE_CHARGING,
        THUNDERSTRIKE_CHARGER_STATE_FULL,
        THUNDERSTRIKE_CHARGER_STATE_FAILED = 8,
} __packed;
static_assert(sizeof(enum thunderstrike_charger_state) == 1);

struct thunderstrike_hostcmd_charger {
        u8 connected;
        enum thunderstrike_charger_type type;
        enum thunderstrike_charger_state state;
} __packed;

struct thunderstrike_hostcmd_board_info {
        __le16 revision;
        __le16 serial[7];
} __packed;

struct thunderstrike_hostcmd_haptics {
        u8 motor_left;
        u8 motor_right;
} __packed;

struct thunderstrike_hostcmd_resp_report {
        u8 report_id; /* THUNDERSTRIKE_HOSTCMD_RESP_REPORT_ID */
        u8 cmd_id;
        u8 reserved_at_10;

        union {
                struct thunderstrike_hostcmd_board_info board_info;
                struct thunderstrike_hostcmd_haptics motors;
                __le16 fw_version;
                enum thunderstrike_led_state led_state;
                struct thunderstrike_hostcmd_battery battery;
                struct thunderstrike_hostcmd_charger charger;
                u8 payload[30];
        } __packed;
} __packed;
static_assert(sizeof(struct thunderstrike_hostcmd_resp_report) ==
              THUNDERSTRIKE_HOSTCMD_REPORT_SIZE);

struct thunderstrike_hostcmd_req_report {
        u8 report_id; /* THUNDERSTRIKE_HOSTCMD_REQ_REPORT_ID */
        u8 cmd_id;
        u8 reserved_at_10;

        union {
                struct __packed {
                        u8 update;
                        enum thunderstrike_led_state state;
                } led;
                struct __packed {
                        u8 update;
                        struct thunderstrike_hostcmd_haptics motors;
                } haptics;
        } __packed;
        u8 reserved_at_30[27];
} __packed;
static_assert(sizeof(struct thunderstrike_hostcmd_req_report) ==
              THUNDERSTRIKE_HOSTCMD_REPORT_SIZE);

/* Common struct for shield accessories. */
struct shield_device {
        struct hid_device *hdev;
        struct power_supply_dev battery_dev;

        unsigned long initialized_flags;
        const char *codename;
        u16 fw_version;
        struct {
                u16 revision;
                char serial_number[15];
        } board_info;
};

/*
 * Non-trivial to uniquely identify Thunderstrike controllers at initialization
 * time. Use an ID allocator to help with this.
 */
static DEFINE_IDA(thunderstrike_ida);

struct thunderstrike {
        struct shield_device base;

        int id;

        /* Sub-devices */
        struct input_dev *haptics_dev;
        struct led_classdev led_dev;

        /* Resources */
        void *req_report_dmabuf;
        unsigned long update_flags;
        struct thunderstrike_hostcmd_haptics haptics_val;
        spinlock_t haptics_update_lock;
        u8 led_state : 1;
        enum thunderstrike_led_state led_value;
        struct thunderstrike_psy_prop_values psy_stats;
        spinlock_t psy_stats_lock;
        struct timer_list psy_stats_timer;
        struct work_struct hostcmd_req_work;
};

static inline void thunderstrike_hostcmd_req_report_init(
        struct thunderstrike_hostcmd_req_report *report, u8 cmd_id)
{
        memset(report, 0, sizeof(*report));
        report->report_id = THUNDERSTRIKE_HOSTCMD_REQ_REPORT_ID;
        report->cmd_id = cmd_id;
}

static inline void shield_strrev(char *dest, size_t len, u16 rev)
{
        dest[0] = ('A' - 1) + (rev >> 8);
        snprintf(&dest[1], len - 1, "%02X", 0xff & rev);
}

static struct input_dev *shield_allocate_input_dev(struct hid_device *hdev,
                                                   const char *name_suffix)
{
        struct input_dev *idev;

        idev = input_allocate_device();
        if (!idev)
                goto err_device;

        idev->id.bustype = hdev->bus;
        idev->id.vendor = hdev->vendor;
        idev->id.product = hdev->product;
        idev->id.version = hdev->version;
        idev->uniq = hdev->uniq;
        idev->name = devm_kasprintf(&hdev->dev, GFP_KERNEL, "%s %s", hdev->name,
                                    name_suffix);
        if (!idev->name)
                goto err_name;

        input_set_drvdata(idev, hdev);

        return idev;

err_name:
        input_free_device(idev);
err_device:
        return ERR_PTR(-ENOMEM);
}

static struct input_dev *shield_haptics_create(
        struct shield_device *dev,
        int (*play_effect)(struct input_dev *, void *, struct ff_effect *))
{
        struct input_dev *haptics;
        int ret;

        if (!IS_ENABLED(CONFIG_NVIDIA_SHIELD_FF))
                return NULL;

        haptics = shield_allocate_input_dev(dev->hdev, "Haptics");
        if (IS_ERR(haptics))
                return haptics;

        input_set_capability(haptics, EV_FF, FF_RUMBLE);
        ret = input_ff_create_memless(haptics, NULL, play_effect);
        if (ret)
                goto err;

        ret = input_register_device(haptics);
        if (ret)
                goto err;

        return haptics;

err:
        input_free_device(haptics);
        return ERR_PTR(ret);
}

static inline void thunderstrike_send_hostcmd_request(struct thunderstrike *ts)
{
        struct thunderstrike_hostcmd_req_report *report = ts->req_report_dmabuf;
        struct shield_device *shield_dev = &ts->base;
        int ret;

        ret = hid_hw_raw_request(shield_dev->hdev, report->report_id,
                                 ts->req_report_dmabuf,
                                 THUNDERSTRIKE_HOSTCMD_REPORT_SIZE,
                                 HID_OUTPUT_REPORT, HID_REQ_SET_REPORT);

        if (ret < 0) {
                hid_err(shield_dev->hdev,
                        "Failed to output Thunderstrike HOSTCMD request HID report due to %pe\n",
                        ERR_PTR(ret));
        }
}

static void thunderstrike_hostcmd_req_work_handler(struct work_struct *work)
{
        struct thunderstrike *ts =
                container_of(work, struct thunderstrike, hostcmd_req_work);
        struct thunderstrike_hostcmd_req_report *report;
        unsigned long flags;

        report = ts->req_report_dmabuf;

        if (test_and_clear_bit(THUNDERSTRIKE_FW_VERSION_UPDATE, &ts->update_flags)) {
                thunderstrike_hostcmd_req_report_init(
                        report, THUNDERSTRIKE_HOSTCMD_ID_FW_VERSION);
                thunderstrike_send_hostcmd_request(ts);
        }

        if (test_and_clear_bit(THUNDERSTRIKE_LED_UPDATE, &ts->update_flags)) {
                thunderstrike_hostcmd_req_report_init(report, THUNDERSTRIKE_HOSTCMD_ID_LED);
                report->led.update = 1;
                report->led.state = ts->led_value;
                thunderstrike_send_hostcmd_request(ts);
        }

        if (test_and_clear_bit(THUNDERSTRIKE_POWER_SUPPLY_STATS_UPDATE, &ts->update_flags)) {
                thunderstrike_hostcmd_req_report_init(
                        report, THUNDERSTRIKE_HOSTCMD_ID_BATTERY);
                thunderstrike_send_hostcmd_request(ts);

                thunderstrike_hostcmd_req_report_init(
                        report, THUNDERSTRIKE_HOSTCMD_ID_CHARGER);
                thunderstrike_send_hostcmd_request(ts);
        }

        if (test_and_clear_bit(THUNDERSTRIKE_BOARD_INFO_UPDATE, &ts->update_flags)) {
                thunderstrike_hostcmd_req_report_init(
                        report, THUNDERSTRIKE_HOSTCMD_ID_BOARD_INFO);
                thunderstrike_send_hostcmd_request(ts);
        }

        if (test_and_clear_bit(THUNDERSTRIKE_HAPTICS_UPDATE, &ts->update_flags)) {
                thunderstrike_hostcmd_req_report_init(
                        report, THUNDERSTRIKE_HOSTCMD_ID_HAPTICS);

                report->haptics.update = 1;
                spin_lock_irqsave(&ts->haptics_update_lock, flags);
                report->haptics.motors = ts->haptics_val;
                spin_unlock_irqrestore(&ts->haptics_update_lock, flags);

                thunderstrike_send_hostcmd_request(ts);
        }
}

static inline void thunderstrike_request_firmware_version(struct thunderstrike *ts)
{
        set_bit(THUNDERSTRIKE_FW_VERSION_UPDATE, &ts->update_flags);
        schedule_work(&ts->hostcmd_req_work);
}

static inline void thunderstrike_request_board_info(struct thunderstrike *ts)
{
        set_bit(THUNDERSTRIKE_BOARD_INFO_UPDATE, &ts->update_flags);
        schedule_work(&ts->hostcmd_req_work);
}

static inline int
thunderstrike_update_haptics(struct thunderstrike *ts,
                             struct thunderstrike_hostcmd_haptics *motors)
{
        unsigned long flags;

        spin_lock_irqsave(&ts->haptics_update_lock, flags);
        ts->haptics_val = *motors;
        spin_unlock_irqrestore(&ts->haptics_update_lock, flags);

        set_bit(THUNDERSTRIKE_HAPTICS_UPDATE, &ts->update_flags);
        schedule_work(&ts->hostcmd_req_work);

        return 0;
}

static int thunderstrike_play_effect(struct input_dev *idev, void *data,
                                     struct ff_effect *effect)
{
        struct hid_device *hdev = input_get_drvdata(idev);
        struct thunderstrike_hostcmd_haptics motors;
        struct shield_device *shield_dev;
        struct thunderstrike *ts;

        if (effect->type != FF_RUMBLE)
                return 0;

        shield_dev = hid_get_drvdata(hdev);
        ts = container_of(shield_dev, struct thunderstrike, base);

        /* Thunderstrike motor values range from 0 to 32 inclusively */
        motors.motor_left = effect->u.rumble.strong_magnitude / 2047;
        motors.motor_right = effect->u.rumble.weak_magnitude / 2047;

        hid_dbg(hdev, "Thunderstrike FF_RUMBLE request, left: %u right: %u\n",
                motors.motor_left, motors.motor_right);

        return thunderstrike_update_haptics(ts, &motors);
}

static enum led_brightness
thunderstrike_led_get_brightness(struct led_classdev *led)
{
        struct hid_device *hdev = to_hid_device(led->dev->parent);
        struct shield_device *shield_dev = hid_get_drvdata(hdev);
        struct thunderstrike *ts;

        ts = container_of(shield_dev, struct thunderstrike, base);

        return ts->led_state;
}

static void thunderstrike_led_set_brightness(struct led_classdev *led,
                                            enum led_brightness value)
{
        struct hid_device *hdev = to_hid_device(led->dev->parent);
        struct shield_device *shield_dev = hid_get_drvdata(hdev);
        struct thunderstrike *ts;

        ts = container_of(shield_dev, struct thunderstrike, base);

        switch (value) {
        case LED_OFF:
                ts->led_value = THUNDERSTRIKE_LED_OFF;
                break;
        default:
                ts->led_value = THUNDERSTRIKE_LED_ON;
                break;
        }

        set_bit(THUNDERSTRIKE_LED_UPDATE, &ts->update_flags);
        schedule_work(&ts->hostcmd_req_work);
}

static int thunderstrike_battery_get_property(struct power_supply *psy,
                                              enum power_supply_property psp,
                                              union power_supply_propval *val)
{
        struct shield_device *shield_dev = power_supply_get_drvdata(psy);
        struct thunderstrike_psy_prop_values prop_values;
        struct thunderstrike *ts;
        int ret = 0;

        ts = container_of(shield_dev, struct thunderstrike, base);
        spin_lock(&ts->psy_stats_lock);
        prop_values = ts->psy_stats;
        spin_unlock(&ts->psy_stats_lock);

        switch (psp) {
        case POWER_SUPPLY_PROP_STATUS:
                val->intval = prop_values.status;
                break;
        case POWER_SUPPLY_PROP_CHARGE_TYPE:
                val->intval = prop_values.charge_type;
                break;
        case POWER_SUPPLY_PROP_PRESENT:
                val->intval = 1;
                break;
        case POWER_SUPPLY_PROP_VOLTAGE_MIN:
                val->intval = prop_values.voltage_min;
                break;
        case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
                val->intval = 2900000; /* 2.9 V */
                break;
        case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
                val->intval = 2200000; /* 2.2 V */
                break;
        case POWER_SUPPLY_PROP_VOLTAGE_NOW:
                val->intval = prop_values.voltage_now;
                break;
        case POWER_SUPPLY_PROP_VOLTAGE_AVG:
                val->intval = prop_values.voltage_avg;
                break;
        case POWER_SUPPLY_PROP_VOLTAGE_BOOT:
                val->intval = prop_values.voltage_boot;
                break;
        case POWER_SUPPLY_PROP_CAPACITY:
                val->intval = prop_values.capacity;
                break;
        case POWER_SUPPLY_PROP_SCOPE:
                val->intval = POWER_SUPPLY_SCOPE_DEVICE;
                break;
        case POWER_SUPPLY_PROP_TEMP:
                val->intval = prop_values.temp;
                break;
        case POWER_SUPPLY_PROP_TEMP_MIN:
                val->intval = 0; /* 0 C */
                break;
        case POWER_SUPPLY_PROP_TEMP_MAX:
                val->intval = 400; /* 40 C */
                break;
        case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
                val->intval = 15; /* 1.5 C */
                break;
        case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
                val->intval = 380; /* 38 C */
                break;
        default:
                ret = -EINVAL;
                break;
        }

        return ret;
}

static inline void thunderstrike_request_psy_stats(struct thunderstrike *ts)
{
        set_bit(THUNDERSTRIKE_POWER_SUPPLY_STATS_UPDATE, &ts->update_flags);
        schedule_work(&ts->hostcmd_req_work);
}

static void thunderstrike_psy_stats_timer_handler(struct timer_list *timer)
{
        struct thunderstrike *ts =
                container_of(timer, struct thunderstrike, psy_stats_timer);

        thunderstrike_request_psy_stats(ts);
        /* Query battery statistics from device every five minutes */
        mod_timer(timer, jiffies + 300 * HZ);
}

static void
thunderstrike_parse_fw_version_payload(struct shield_device *shield_dev,
                                       __le16 fw_version)
{
        shield_dev->fw_version = le16_to_cpu(fw_version);

        set_bit(SHIELD_FW_VERSION_INITIALIZED, &shield_dev->initialized_flags);

        hid_dbg(shield_dev->hdev, "Thunderstrike firmware version 0x%04X\n",
                shield_dev->fw_version);
}

static void
thunderstrike_parse_board_info_payload(struct shield_device *shield_dev,
                                       struct thunderstrike_hostcmd_board_info *board_info)
{
        char board_revision_str[4];
        int i;

        shield_dev->board_info.revision = le16_to_cpu(board_info->revision);
        for (i = 0; i < 7; ++i) {
                u16 val = le16_to_cpu(board_info->serial[i]);

                shield_dev->board_info.serial_number[2 * i] = val & 0xFF;
                shield_dev->board_info.serial_number[2 * i + 1] = val >> 8;
        }
        shield_dev->board_info.serial_number[14] = '\0';

        set_bit(SHIELD_BOARD_INFO_INITIALIZED, &shield_dev->initialized_flags);

        shield_strrev(board_revision_str, 4, shield_dev->board_info.revision);
        hid_dbg(shield_dev->hdev,
                "Thunderstrike BOARD_REVISION_%s (0x%04X) S/N: %s\n",
                board_revision_str, shield_dev->board_info.revision,
                shield_dev->board_info.serial_number);
}

static inline void
thunderstrike_parse_haptics_payload(struct shield_device *shield_dev,
                                    struct thunderstrike_hostcmd_haptics *haptics)
{
        hid_dbg(shield_dev->hdev,
                "Thunderstrike haptics HOSTCMD response, left: %u right: %u\n",
                haptics->motor_left, haptics->motor_right);
}

static void
thunderstrike_parse_led_payload(struct shield_device *shield_dev,
                                enum thunderstrike_led_state led_state)
{
        struct thunderstrike *ts = container_of(shield_dev, struct thunderstrike, base);

        switch (led_state) {
        case THUNDERSTRIKE_LED_OFF:
                ts->led_state = 0;
                break;
        case THUNDERSTRIKE_LED_ON:
                ts->led_state = 1;
                break;
        }

        hid_dbg(shield_dev->hdev, "Thunderstrike led HOSTCMD response, 0x%02X\n", led_state);
}

static void thunderstrike_parse_battery_payload(
        struct shield_device *shield_dev,
        struct thunderstrike_hostcmd_battery *battery)
{
        struct thunderstrike *ts = container_of(shield_dev, struct thunderstrike, base);
        u16 hostcmd_voltage_boot = le16_to_cpu(battery->voltage_boot);
        u16 hostcmd_voltage_avg = le16_to_cpu(battery->voltage_avg);
        u16 hostcmd_voltage_min = le16_to_cpu(battery->voltage_min);
        u16 hostcmd_voltage_now = le16_to_cpu(battery->voltage_now);
        u16 hostcmd_thermistor = le16_to_cpu(battery->thermistor);
        int voltage_boot, voltage_avg, voltage_min, voltage_now;
        struct hid_device *hdev = shield_dev->hdev;
        u8 capacity = battery->capacity;
        int temp;

        /* Convert thunderstrike device values to µV and tenths of degree Celsius */
        voltage_boot = hostcmd_voltage_boot * 1000;
        voltage_avg = hostcmd_voltage_avg * 1000;
        voltage_min = hostcmd_voltage_min * 1000;
        voltage_now = hostcmd_voltage_now * 1000;
        temp = (1378 - (int)hostcmd_thermistor) * 10 / 19;

        /* Copy converted values */
        spin_lock(&ts->psy_stats_lock);
        ts->psy_stats.voltage_boot = voltage_boot;
        ts->psy_stats.voltage_avg = voltage_avg;
        ts->psy_stats.voltage_min = voltage_min;
        ts->psy_stats.voltage_now = voltage_now;
        ts->psy_stats.capacity = capacity;
        ts->psy_stats.temp = temp;
        spin_unlock(&ts->psy_stats_lock);

        set_bit(SHIELD_BATTERY_STATS_INITIALIZED, &shield_dev->initialized_flags);

        hid_dbg(hdev,
                "Thunderstrike battery HOSTCMD response, voltage_avg: %u voltage_now: %u\n",
                hostcmd_voltage_avg, hostcmd_voltage_now);
        hid_dbg(hdev,
                "Thunderstrike battery HOSTCMD response, voltage_boot: %u voltage_min: %u\n",
                hostcmd_voltage_boot, hostcmd_voltage_min);
        hid_dbg(hdev,
                "Thunderstrike battery HOSTCMD response, thermistor: %u\n",
                hostcmd_thermistor);
        hid_dbg(hdev,
                "Thunderstrike battery HOSTCMD response, capacity: %u%%\n",
                capacity);
}

static void thunderstrike_parse_charger_payload(
        struct shield_device *shield_dev,
        struct thunderstrike_hostcmd_charger *charger)
{
        struct thunderstrike *ts = container_of(shield_dev, struct thunderstrike, base);
        int charge_type = POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
        struct hid_device *hdev = shield_dev->hdev;
        int status = POWER_SUPPLY_STATUS_UNKNOWN;

        switch (charger->type) {
        case THUNDERSTRIKE_CHARGER_TYPE_NONE:
                charge_type = POWER_SUPPLY_CHARGE_TYPE_NONE;
                break;
        case THUNDERSTRIKE_CHARGER_TYPE_TRICKLE:
                charge_type = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
                break;
        case THUNDERSTRIKE_CHARGER_TYPE_NORMAL:
                charge_type = POWER_SUPPLY_CHARGE_TYPE_STANDARD;
                break;
        default:
                hid_warn(hdev, "Unhandled Thunderstrike charger HOSTCMD type, %u\n",
                         charger->type);
                break;
        }

        switch (charger->state) {
        case THUNDERSTRIKE_CHARGER_STATE_UNKNOWN:
                status = POWER_SUPPLY_STATUS_UNKNOWN;
                break;
        case THUNDERSTRIKE_CHARGER_STATE_DISABLED:
                /* Indicates charger is disconnected */
                break;
        case THUNDERSTRIKE_CHARGER_STATE_CHARGING:
                status = POWER_SUPPLY_STATUS_CHARGING;
                break;
        case THUNDERSTRIKE_CHARGER_STATE_FULL:
                status = POWER_SUPPLY_STATUS_FULL;
                break;
        case THUNDERSTRIKE_CHARGER_STATE_FAILED:
                status = POWER_SUPPLY_STATUS_NOT_CHARGING;
                hid_err(hdev, "Thunderstrike device failed to charge\n");
                break;
        default:
                hid_warn(hdev, "Unhandled Thunderstrike charger HOSTCMD state, %u\n",
                         charger->state);
                break;
        }

        if (!charger->connected)
                status = POWER_SUPPLY_STATUS_DISCHARGING;

        spin_lock(&ts->psy_stats_lock);
        ts->psy_stats.charge_type = charge_type;
        ts->psy_stats.status = status;
        spin_unlock(&ts->psy_stats_lock);

        set_bit(SHIELD_CHARGER_STATE_INITIALIZED, &shield_dev->initialized_flags);

        hid_dbg(hdev,
                "Thunderstrike charger HOSTCMD response, connected: %u, type: %u, state: %u\n",
                charger->connected, charger->type, charger->state);
}

static inline void thunderstrike_device_init_info(struct shield_device *shield_dev)
{
        struct thunderstrike *ts =
                container_of(shield_dev, struct thunderstrike, base);

        if (!test_bit(SHIELD_FW_VERSION_INITIALIZED, &shield_dev->initialized_flags))
                thunderstrike_request_firmware_version(ts);

        if (!test_bit(SHIELD_BOARD_INFO_INITIALIZED, &shield_dev->initialized_flags))
                thunderstrike_request_board_info(ts);

        if (!test_bit(SHIELD_BATTERY_STATS_INITIALIZED, &shield_dev->initialized_flags) ||
            !test_bit(SHIELD_CHARGER_STATE_INITIALIZED, &shield_dev->initialized_flags))
                thunderstrike_psy_stats_timer_handler(&ts->psy_stats_timer);
}

static int thunderstrike_parse_report(struct shield_device *shield_dev,
                                      struct hid_report *report, u8 *data,
                                      int size)
{
        struct thunderstrike_hostcmd_resp_report *hostcmd_resp_report;
        struct hid_device *hdev = shield_dev->hdev;

        switch (report->id) {
        case THUNDERSTRIKE_HOSTCMD_RESP_REPORT_ID:
                if (size != THUNDERSTRIKE_HOSTCMD_REPORT_SIZE) {
                        hid_err(hdev,
                                "Encountered Thunderstrike HOSTCMD HID report with unexpected size %d\n",
                                size);
                        return -EINVAL;
                }

                hostcmd_resp_report =
                        (struct thunderstrike_hostcmd_resp_report *)data;

                switch (hostcmd_resp_report->cmd_id) {
                case THUNDERSTRIKE_HOSTCMD_ID_FW_VERSION:
                        thunderstrike_parse_fw_version_payload(
                                shield_dev, hostcmd_resp_report->fw_version);
                        break;
                case THUNDERSTRIKE_HOSTCMD_ID_LED:
                        thunderstrike_parse_led_payload(shield_dev, hostcmd_resp_report->led_state);
                        break;
                case THUNDERSTRIKE_HOSTCMD_ID_BATTERY:
                        thunderstrike_parse_battery_payload(shield_dev,
                                                            &hostcmd_resp_report->battery);
                        break;
                case THUNDERSTRIKE_HOSTCMD_ID_BOARD_INFO:
                        thunderstrike_parse_board_info_payload(
                                shield_dev, &hostcmd_resp_report->board_info);
                        break;
                case THUNDERSTRIKE_HOSTCMD_ID_HAPTICS:
                        thunderstrike_parse_haptics_payload(
                                shield_dev, &hostcmd_resp_report->motors);
                        break;
                case THUNDERSTRIKE_HOSTCMD_ID_USB_INIT:
                        /* May block HOSTCMD requests till received initially */
                        thunderstrike_device_init_info(shield_dev);
                        break;
                case THUNDERSTRIKE_HOSTCMD_ID_CHARGER:
                        /* May block HOSTCMD requests till received initially */
                        thunderstrike_device_init_info(shield_dev);

                        thunderstrike_parse_charger_payload(
                                shield_dev, &hostcmd_resp_report->charger);
                        break;
                default:
                        hid_warn(hdev,
                                 "Unhandled Thunderstrike HOSTCMD id %d\n",
                                 hostcmd_resp_report->cmd_id);
                        return -ENOENT;
                }

                break;
        default:
                return 0;
        }

        return 0;
}

static inline int thunderstrike_led_create(struct thunderstrike *ts)
{
        struct led_classdev *led = &ts->led_dev;

        led->name = devm_kasprintf(&ts->base.hdev->dev, GFP_KERNEL,
                                   "thunderstrike%d:blue:led", ts->id);
        if (!led->name)
                return -ENOMEM;
        led->max_brightness = 1;
        led->flags = LED_CORE_SUSPENDRESUME | LED_RETAIN_AT_SHUTDOWN;
        led->brightness_get = &thunderstrike_led_get_brightness;
        led->brightness_set = &thunderstrike_led_set_brightness;

        return led_classdev_register(&ts->base.hdev->dev, led);
}

static inline int thunderstrike_psy_create(struct shield_device *shield_dev)
{
        struct thunderstrike *ts = container_of(shield_dev, struct thunderstrike, base);
        struct power_supply_config psy_cfg = { .drv_data = shield_dev, };
        struct hid_device *hdev = shield_dev->hdev;
        int ret;

        /*
         * Set an initial capacity and temperature value to avoid prematurely
         * triggering alerts. Will be replaced by values queried from initial
         * HOSTCMD requests.
         */
        ts->psy_stats.capacity = 100;
        ts->psy_stats.temp = 182;

        shield_dev->battery_dev.desc.properties = thunderstrike_battery_props;
        shield_dev->battery_dev.desc.num_properties =
                ARRAY_SIZE(thunderstrike_battery_props);
        shield_dev->battery_dev.desc.get_property = thunderstrike_battery_get_property;
        shield_dev->battery_dev.desc.type = POWER_SUPPLY_TYPE_BATTERY;
        shield_dev->battery_dev.desc.name =
                devm_kasprintf(&ts->base.hdev->dev, GFP_KERNEL,
                               "thunderstrike_%d", ts->id);
        if (!shield_dev->battery_dev.desc.name)
                return -ENOMEM;

        shield_dev->battery_dev.psy = power_supply_register(
                &hdev->dev, &shield_dev->battery_dev.desc, &psy_cfg);
        if (IS_ERR(shield_dev->battery_dev.psy)) {
                hid_err(hdev, "Failed to register Thunderstrike battery device\n");
                return PTR_ERR(shield_dev->battery_dev.psy);
        }

        ret = power_supply_powers(shield_dev->battery_dev.psy, &hdev->dev);
        if (ret) {
                hid_err(hdev, "Failed to associate battery device to Thunderstrike\n");
                goto err;
        }

        return 0;

err:
        power_supply_unregister(shield_dev->battery_dev.psy);
        return ret;
}

static struct shield_device *thunderstrike_create(struct hid_device *hdev)
{
        struct shield_device *shield_dev;
        struct thunderstrike *ts;
        int ret;

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

        ts->req_report_dmabuf = devm_kzalloc(
                &hdev->dev, THUNDERSTRIKE_HOSTCMD_REPORT_SIZE, GFP_KERNEL);
        if (!ts->req_report_dmabuf)
                return ERR_PTR(-ENOMEM);

        shield_dev = &ts->base;
        shield_dev->hdev = hdev;
        shield_dev->codename = "Thunderstrike";

        spin_lock_init(&ts->haptics_update_lock);
        spin_lock_init(&ts->psy_stats_lock);
        INIT_WORK(&ts->hostcmd_req_work, thunderstrike_hostcmd_req_work_handler);

        hid_set_drvdata(hdev, shield_dev);

        ts->id = ida_alloc(&thunderstrike_ida, GFP_KERNEL);
        if (ts->id < 0)
                return ERR_PTR(ts->id);

        ts->haptics_dev = shield_haptics_create(shield_dev, thunderstrike_play_effect);
        if (IS_ERR(ts->haptics_dev)) {
                hid_err(hdev, "Failed to create Thunderstrike haptics instance\n");
                ret = PTR_ERR(ts->haptics_dev);
                goto err_id;
        }

        ret = thunderstrike_psy_create(shield_dev);
        if (ret) {
                hid_err(hdev, "Failed to create Thunderstrike power supply instance\n");
                goto err_haptics;
        }

        ret = thunderstrike_led_create(ts);
        if (ret) {
                hid_err(hdev, "Failed to create Thunderstrike LED instance\n");
                goto err_psy;
        }

        timer_setup(&ts->psy_stats_timer, thunderstrike_psy_stats_timer_handler, 0);

        hid_info(hdev, "Registered Thunderstrike controller\n");
        return shield_dev;

err_psy:
        power_supply_unregister(shield_dev->battery_dev.psy);
err_haptics:
        if (ts->haptics_dev)
                input_unregister_device(ts->haptics_dev);
err_id:
        ida_free(&thunderstrike_ida, ts->id);
        return ERR_PTR(ret);
}

static void thunderstrike_destroy(struct thunderstrike *ts)
{
        led_classdev_unregister(&ts->led_dev);
        power_supply_unregister(ts->base.battery_dev.psy);
        if (ts->haptics_dev)
                input_unregister_device(ts->haptics_dev);
        ida_free(&thunderstrike_ida, ts->id);
}

static int android_input_mapping(struct hid_device *hdev, struct hid_input *hi,
                                 struct hid_field *field,
                                 struct hid_usage *usage, unsigned long **bit,
                                 int *max)
{
        if ((usage->hid & HID_USAGE_PAGE) != HID_UP_CONSUMER)
                return 0;

        switch (usage->hid & HID_USAGE) {
        case HID_USAGE_ANDROID_PLAYPAUSE_BTN:
                android_map_key(KEY_PLAYPAUSE);
                break;
        case HID_USAGE_ANDROID_VOLUMEUP_BTN:
                android_map_key(KEY_VOLUMEUP);
                break;
        case HID_USAGE_ANDROID_VOLUMEDOWN_BTN:
                android_map_key(KEY_VOLUMEDOWN);
                break;
        case HID_USAGE_ANDROID_SEARCH_BTN:
                android_map_key(BTN_Z);
                break;
        case HID_USAGE_ANDROID_HOME_BTN:
                android_map_key(BTN_MODE);
                break;
        case HID_USAGE_ANDROID_BACK_BTN:
                android_map_key(BTN_SELECT);
                break;
        default:
                return 0;
        }

        return 1;
}

static ssize_t firmware_version_show(struct device *dev,
                                     struct device_attribute *attr, char *buf)
{
        struct hid_device *hdev = to_hid_device(dev);
        struct shield_device *shield_dev;
        int ret;

        shield_dev = hid_get_drvdata(hdev);

        if (test_bit(SHIELD_FW_VERSION_INITIALIZED, &shield_dev->initialized_flags))
                ret = sysfs_emit(buf, "0x%04X\n", shield_dev->fw_version);
        else
                ret = sysfs_emit(buf, NOT_INIT_STR "\n");

        return ret;
}

static DEVICE_ATTR_RO(firmware_version);

static ssize_t hardware_version_show(struct device *dev,
                                     struct device_attribute *attr, char *buf)
{
        struct hid_device *hdev = to_hid_device(dev);
        struct shield_device *shield_dev;
        char board_revision_str[4];
        int ret;

        shield_dev = hid_get_drvdata(hdev);

        if (test_bit(SHIELD_BOARD_INFO_INITIALIZED, &shield_dev->initialized_flags)) {
                shield_strrev(board_revision_str, 4, shield_dev->board_info.revision);
                ret = sysfs_emit(buf, "%s BOARD_REVISION_%s (0x%04X)\n",
                                 shield_dev->codename, board_revision_str,
                                 shield_dev->board_info.revision);
        } else
                ret = sysfs_emit(buf, NOT_INIT_STR "\n");

        return ret;
}

static DEVICE_ATTR_RO(hardware_version);

static ssize_t serial_number_show(struct device *dev,
                                  struct device_attribute *attr, char *buf)
{
        struct hid_device *hdev = to_hid_device(dev);
        struct shield_device *shield_dev;
        int ret;

        shield_dev = hid_get_drvdata(hdev);

        if (test_bit(SHIELD_BOARD_INFO_INITIALIZED, &shield_dev->initialized_flags))
                ret = sysfs_emit(buf, "%s\n", shield_dev->board_info.serial_number);
        else
                ret = sysfs_emit(buf, NOT_INIT_STR "\n");

        return ret;
}

static DEVICE_ATTR_RO(serial_number);

static struct attribute *shield_device_attrs[] = {
        &dev_attr_firmware_version.attr,
        &dev_attr_hardware_version.attr,
        &dev_attr_serial_number.attr,
        NULL,
};
ATTRIBUTE_GROUPS(shield_device);

static int shield_raw_event(struct hid_device *hdev, struct hid_report *report,
                            u8 *data, int size)
{
        struct shield_device *dev = hid_get_drvdata(hdev);

        return thunderstrike_parse_report(dev, report, data, size);
}

static int shield_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
        struct shield_device *shield_dev = NULL;
        struct thunderstrike *ts;
        int ret;

        ret = hid_parse(hdev);
        if (ret) {
                hid_err(hdev, "Parse failed\n");
                return ret;
        }

        switch (id->product) {
        case USB_DEVICE_ID_NVIDIA_THUNDERSTRIKE_CONTROLLER:
                shield_dev = thunderstrike_create(hdev);
                break;
        }

        if (unlikely(!shield_dev)) {
                hid_err(hdev, "Failed to identify SHIELD device\n");
                return -ENODEV;
        }
        if (IS_ERR(shield_dev)) {
                hid_err(hdev, "Failed to create SHIELD device\n");
                return PTR_ERR(shield_dev);
        }

        ts = container_of(shield_dev, struct thunderstrike, base);

        ret = hid_hw_start(hdev, HID_CONNECT_HIDINPUT);
        if (ret) {
                hid_err(hdev, "Failed to start HID device\n");
                goto err_ts_create;
        }

        ret = hid_hw_open(hdev);
        if (ret) {
                hid_err(hdev, "Failed to open HID device\n");
                goto err_stop;
        }

        thunderstrike_device_init_info(shield_dev);

        return ret;

err_stop:
        hid_hw_stop(hdev);
err_ts_create:
        thunderstrike_destroy(ts);
        return ret;
}

static void shield_remove(struct hid_device *hdev)
{
        struct shield_device *dev = hid_get_drvdata(hdev);
        struct thunderstrike *ts;

        ts = container_of(dev, struct thunderstrike, base);

        hid_hw_close(hdev);
        thunderstrike_destroy(ts);
        timer_delete_sync(&ts->psy_stats_timer);
        cancel_work_sync(&ts->hostcmd_req_work);
        hid_hw_stop(hdev);
}

static const struct hid_device_id shield_devices[] = {
        { HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_NVIDIA,
                               USB_DEVICE_ID_NVIDIA_THUNDERSTRIKE_CONTROLLER) },
        { HID_USB_DEVICE(USB_VENDOR_ID_NVIDIA,
                         USB_DEVICE_ID_NVIDIA_THUNDERSTRIKE_CONTROLLER) },
        { }
};
MODULE_DEVICE_TABLE(hid, shield_devices);

static struct hid_driver shield_driver = {
        .name          = "shield",
        .id_table      = shield_devices,
        .input_mapping = android_input_mapping,
        .probe         = shield_probe,
        .remove        = shield_remove,
        .raw_event     = shield_raw_event,
        .driver = {
                .dev_groups = shield_device_groups,
        },
};
module_hid_driver(shield_driver);

MODULE_AUTHOR("Rahul Rameshbabu <rrameshbabu@nvidia.com>");
MODULE_DESCRIPTION("HID Driver for NVIDIA SHIELD peripherals.");
MODULE_LICENSE("GPL");