SDL/src/joystick/hidapi/SDL_hidapi_shield.c

/*
  Simple DirectMedia Layer
  Copyright (C) 1997-2022 Sam Lantinga <[email protected]>

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.
*/
#include "SDL_internal.h"

#ifdef SDL_JOYSTICK_HIDAPI

#include "../SDL_sysjoystick.h"
#include "SDL_hidapijoystick_c.h"
#include "SDL_hidapi_rumble.h"

#ifdef SDL_JOYSTICK_HIDAPI_SHIELD

/* Define this if you want to log all packets from the controller */
/*#define DEBUG_SHIELD_PROTOCOL*/

#define CMD_BATTERY_STATE 0x07
#define CMD_RUMBLE        0x39
#define CMD_CHARGE_STATE  0x3A

/* Milliseconds between polls of battery state */
#define BATTERY_POLL_INTERVAL_MS 60000

/* Milliseconds between retransmission of rumble to keep motors running */
#define RUMBLE_REFRESH_INTERVAL_MS 500

/* Reports that are too small are dropped over Bluetooth */
#define HID_REPORT_SIZE 33

enum
{
    SDL_CONTROLLER_BUTTON_SHIELD_V103_TOUCHPAD = SDL_CONTROLLER_BUTTON_MISC1 + 1,
    SDL_CONTROLLER_BUTTON_SHIELD_V103_MINUS,
    SDL_CONTROLLER_BUTTON_SHIELD_V103_PLUS,
    SDL_CONTROLLER_NUM_SHIELD_V103_BUTTONS,

    SDL_CONTROLLER_NUM_SHIELD_V104_BUTTONS = SDL_CONTROLLER_BUTTON_MISC1 + 1,
};

typedef enum
{
    k_ShieldReportIdControllerState = 0x01,
    k_ShieldReportIdControllerTouch = 0x02,
    k_ShieldReportIdCommandResponse = 0x03,
    k_ShieldReportIdCommandRequest = 0x04,
} EShieldReportId;

/* This same report structure is used for both requests and responses */
typedef struct
{
    Uint8 report_id;
    Uint8 cmd;
    Uint8 seq_num;
    Uint8 payload[HID_REPORT_SIZE - 3];
} ShieldCommandReport_t;
SDL_COMPILE_TIME_ASSERT(ShieldCommandReport_t, sizeof(ShieldCommandReport_t) == HID_REPORT_SIZE);

typedef struct
{
    Uint8 seq_num;

    SDL_JoystickPowerLevel battery_level;
    SDL_bool charging;
    Uint64 last_battery_query_time;

    SDL_bool rumble_report_pending;
    SDL_bool rumble_update_pending;
    Uint8 left_motor_amplitude;
    Uint8 right_motor_amplitude;
    Uint64 last_rumble_time;

    Uint8 last_state[USB_PACKET_LENGTH];
} SDL_DriverShield_Context;

static void HIDAPI_DriverShield_RegisterHints(SDL_HintCallback callback, void *userdata)
{
    SDL_AddHintCallback(SDL_HINT_JOYSTICK_HIDAPI_SHIELD, callback, userdata);
}

static void HIDAPI_DriverShield_UnregisterHints(SDL_HintCallback callback, void *userdata)
{
    SDL_DelHintCallback(SDL_HINT_JOYSTICK_HIDAPI_SHIELD, callback, userdata);
}

static SDL_bool HIDAPI_DriverShield_IsEnabled(void)
{
    return SDL_GetHintBoolean(SDL_HINT_JOYSTICK_HIDAPI_SHIELD, SDL_GetHintBoolean(SDL_HINT_JOYSTICK_HIDAPI, SDL_HIDAPI_DEFAULT));
}

static SDL_bool HIDAPI_DriverShield_IsSupportedDevice(SDL_HIDAPI_Device *device, const char *name, SDL_GameControllerType type, Uint16 vendor_id, Uint16 product_id, Uint16 version, int interface_number, int interface_class, int interface_subclass, int interface_protocol)
{
    return (type == SDL_CONTROLLER_TYPE_NVIDIA_SHIELD) ? SDL_TRUE : SDL_FALSE;
}

static SDL_bool HIDAPI_DriverShield_InitDevice(SDL_HIDAPI_Device *device)
{
    SDL_DriverShield_Context *ctx;

    ctx = (SDL_DriverShield_Context *)SDL_calloc(1, sizeof(*ctx));
    if (ctx == NULL) {
        SDL_OutOfMemory();
        return SDL_FALSE;
    }
    device->context = ctx;

    device->type = SDL_CONTROLLER_TYPE_NVIDIA_SHIELD;
    HIDAPI_SetDeviceName(device, "NVIDIA SHIELD Controller");

    return HIDAPI_JoystickConnected(device, NULL);
}

static int HIDAPI_DriverShield_GetDevicePlayerIndex(SDL_HIDAPI_Device *device, SDL_JoystickID instance_id)
{
    return -1;
}

static void HIDAPI_DriverShield_SetDevicePlayerIndex(SDL_HIDAPI_Device *device, SDL_JoystickID instance_id, int player_index)
{
}

static int HIDAPI_DriverShield_SendCommand(SDL_HIDAPI_Device *device, Uint8 cmd, const void *data, int size)
{
    SDL_DriverShield_Context *ctx = (SDL_DriverShield_Context *)device->context;
    ShieldCommandReport_t cmd_pkt;

    if (size > sizeof(cmd_pkt.payload)) {
        return SDL_SetError("Command data exceeds HID report size");
    }

    if (SDL_HIDAPI_LockRumble() != 0) {
        return -1;
    }

    cmd_pkt.report_id = k_ShieldReportIdCommandRequest;
    cmd_pkt.cmd = cmd;
    cmd_pkt.seq_num = ctx->seq_num++;
    if (data) {
        SDL_memcpy(cmd_pkt.payload, data, size);
    }

    /* Zero unused data in the payload */
    if (size != sizeof(cmd_pkt.payload)) {
        SDL_memset(&cmd_pkt.payload[size], 0, sizeof(cmd_pkt.payload) - size);
    }

    if (SDL_HIDAPI_SendRumbleAndUnlock(device, (Uint8 *)&cmd_pkt, sizeof(cmd_pkt)) != sizeof(cmd_pkt)) {
        return SDL_SetError("Couldn't send command packet");
    }

    return 0;
}

static SDL_bool HIDAPI_DriverShield_OpenJoystick(SDL_HIDAPI_Device *device, SDL_Joystick *joystick)
{
    SDL_DriverShield_Context *ctx = (SDL_DriverShield_Context *)device->context;

    SDL_AssertJoysticksLocked();

    ctx->rumble_report_pending = SDL_FALSE;
    ctx->rumble_update_pending = SDL_FALSE;
    ctx->left_motor_amplitude = 0;
    ctx->right_motor_amplitude = 0;
    ctx->last_rumble_time = 0;
    SDL_zeroa(ctx->last_state);

    /* Initialize the joystick capabilities */
    if (device->product_id == USB_PRODUCT_NVIDIA_SHIELD_CONTROLLER_V103) {
        joystick->nbuttons = SDL_CONTROLLER_NUM_SHIELD_V103_BUTTONS;
        joystick->naxes = SDL_CONTROLLER_AXIS_MAX;
        joystick->epowerlevel = SDL_JOYSTICK_POWER_WIRED;

        SDL_PrivateJoystickAddTouchpad(joystick, 1);
    } else {
        joystick->nbuttons = SDL_CONTROLLER_NUM_SHIELD_V104_BUTTONS;
        joystick->naxes = SDL_CONTROLLER_AXIS_MAX;
        joystick->epowerlevel = SDL_JOYSTICK_POWER_UNKNOWN;
    }

    /* Request battery and charging info */
    ctx->last_battery_query_time = SDL_GetTicks();
    HIDAPI_DriverShield_SendCommand(device, CMD_CHARGE_STATE, NULL, 0);
    HIDAPI_DriverShield_SendCommand(device, CMD_BATTERY_STATE, NULL, 0);

    return SDL_TRUE;
}

static int HIDAPI_DriverShield_SendNextRumble(SDL_HIDAPI_Device *device)
{
    SDL_DriverShield_Context *ctx = device->context;
    Uint8 rumble_data[3];

    if (!ctx->rumble_update_pending) {
        return 0;
    }

    rumble_data[0] = 0x01; /* enable */
    rumble_data[1] = ctx->left_motor_amplitude;
    rumble_data[2] = ctx->right_motor_amplitude;

    ctx->rumble_update_pending = SDL_FALSE;
    ctx->last_rumble_time = SDL_GetTicks();

    return HIDAPI_DriverShield_SendCommand(device, CMD_RUMBLE, rumble_data, sizeof(rumble_data));
}

static int HIDAPI_DriverShield_RumbleJoystick(SDL_HIDAPI_Device *device, SDL_Joystick *joystick, Uint16 low_frequency_rumble, Uint16 high_frequency_rumble)
{
    if (device->product_id == USB_PRODUCT_NVIDIA_SHIELD_CONTROLLER_V103) {
        Uint8 rumble_packet[] = { 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };

        rumble_packet[2] = (low_frequency_rumble >> 8);
        rumble_packet[4] = (high_frequency_rumble >> 8);

        if (SDL_HIDAPI_SendRumble(device, rumble_packet, sizeof(rumble_packet)) != sizeof(rumble_packet)) {
            return SDL_SetError("Couldn't send rumble packet");
        }
        return 0;

    } else {
        SDL_DriverShield_Context *ctx = device->context;

        /* The rumble motors are quite intense, so tone down the intensity like the official driver does */
        ctx->left_motor_amplitude = low_frequency_rumble >> 11;
        ctx->right_motor_amplitude = high_frequency_rumble >> 11;
        ctx->rumble_update_pending = SDL_TRUE;

        if (ctx->rumble_report_pending) {
            /* We will service this after the hardware acknowledges the previous request */
            return 0;
        }

        return HIDAPI_DriverShield_SendNextRumble(device);
    }
}

static int HIDAPI_DriverShield_RumbleJoystickTriggers(SDL_HIDAPI_Device *device, SDL_Joystick *joystick, Uint16 left_rumble, Uint16 right_rumble)
{
    return SDL_Unsupported();
}

static Uint32 HIDAPI_DriverShield_GetJoystickCapabilities(SDL_HIDAPI_Device *device, SDL_Joystick *joystick)
{
    return SDL_JOYCAP_RUMBLE;
}

static int HIDAPI_DriverShield_SetJoystickLED(SDL_HIDAPI_Device *device, SDL_Joystick *joystick, Uint8 red, Uint8 green, Uint8 blue)
{
    return SDL_Unsupported();
}

static int HIDAPI_DriverShield_SendJoystickEffect(SDL_HIDAPI_Device *device, SDL_Joystick *joystick, const void *data, int size)
{
    const Uint8 *data_bytes = data;

    if (size > 1) {
        /* Single command byte followed by a variable length payload */
        return HIDAPI_DriverShield_SendCommand(device, data_bytes[0], &data_bytes[1], size - 1);
    } else if (size == 1) {
        /* Single command byte with no payload */
        return HIDAPI_DriverShield_SendCommand(device, data_bytes[0], NULL, 0);
    } else {
        return SDL_SetError("Effect data must at least contain a command byte");
    }
}

static int HIDAPI_DriverShield_SetJoystickSensorsEnabled(SDL_HIDAPI_Device *device, SDL_Joystick *joystick, SDL_bool enabled)
{
    return SDL_Unsupported();
}

static void HIDAPI_DriverShield_HandleStatePacketV103(SDL_Joystick *joystick, SDL_DriverShield_Context *ctx, Uint8 *data, int size)
{
    Uint64 timestamp = SDL_GetTicksNS();

    if (ctx->last_state[3] != data[3]) {
        SDL_bool dpad_up = SDL_FALSE;
        SDL_bool dpad_down = SDL_FALSE;
        SDL_bool dpad_left = SDL_FALSE;
        SDL_bool dpad_right = SDL_FALSE;

        switch (data[3]) {
        case 0:
            dpad_up = SDL_TRUE;
            break;
        case 1:
            dpad_up = SDL_TRUE;
            dpad_right = SDL_TRUE;
            break;
        case 2:
            dpad_right = SDL_TRUE;
            break;
        case 3:
            dpad_right = SDL_TRUE;
            dpad_down = SDL_TRUE;
            break;
        case 4:
            dpad_down = SDL_TRUE;
            break;
        case 5:
            dpad_left = SDL_TRUE;
            dpad_down = SDL_TRUE;
            break;
        case 6:
            dpad_left = SDL_TRUE;
            break;
        case 7:
            dpad_up = SDL_TRUE;
            dpad_left = SDL_TRUE;
            break;
        default:
            break;
        }
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_DPAD_DOWN, dpad_down);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_DPAD_UP, dpad_up);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_DPAD_RIGHT, dpad_right);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_DPAD_LEFT, dpad_left);
    }

    if (ctx->last_state[1] != data[1]) {
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_A, (data[1] & 0x01) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_B, (data[1] & 0x02) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_X, (data[1] & 0x04) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_Y, (data[1] & 0x08) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_LEFTSHOULDER, (data[1] & 0x10) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_RIGHTSHOULDER, (data[1] & 0x20) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_LEFTSTICK, (data[1] & 0x40) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_RIGHTSTICK, (data[1] & 0x80) ? SDL_PRESSED : SDL_RELEASED);
    }

    if (ctx->last_state[2] != data[2]) {
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_START, (data[2] & 0x02) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_SHIELD_V103_PLUS, (data[2] & 0x08) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_SHIELD_V103_MINUS, (data[2] & 0x10) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_GUIDE, (data[2] & 0x20) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_BACK, (data[2] & 0x40) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_MISC1, (data[2] & 0x80) ? SDL_PRESSED : SDL_RELEASED);
    }

    SDL_PrivateJoystickAxis(timestamp, joystick, SDL_CONTROLLER_AXIS_LEFTX, SDL_SwapLE16(*(Sint16 *)&data[4]) - 0x8000);
    SDL_PrivateJoystickAxis(timestamp, joystick, SDL_CONTROLLER_AXIS_LEFTY, SDL_SwapLE16(*(Sint16 *)&data[6]) - 0x8000);

    SDL_PrivateJoystickAxis(timestamp, joystick, SDL_CONTROLLER_AXIS_RIGHTX, SDL_SwapLE16(*(Sint16 *)&data[8]) - 0x8000);
    SDL_PrivateJoystickAxis(timestamp, joystick, SDL_CONTROLLER_AXIS_RIGHTY, SDL_SwapLE16(*(Sint16 *)&data[10]) - 0x8000);

    SDL_PrivateJoystickAxis(timestamp, joystick, SDL_CONTROLLER_AXIS_TRIGGERLEFT, SDL_SwapLE16(*(Sint16 *)&data[12]) - 0x8000);
    SDL_PrivateJoystickAxis(timestamp, joystick, SDL_CONTROLLER_AXIS_TRIGGERRIGHT, SDL_SwapLE16(*(Sint16 *)&data[14]) - 0x8000);

    SDL_memcpy(ctx->last_state, data, SDL_min(size, sizeof(ctx->last_state)));
}

#undef clamp
#define clamp(val, min, max) (((val) > (max)) ? (max) : (((val) < (min)) ? (min) : (val)))

static void HIDAPI_DriverShield_HandleTouchPacketV103(SDL_Joystick *joystick, SDL_DriverShield_Context *ctx, const Uint8 *data, int size)
{
    Uint8 touchpad_state;
    float touchpad_x, touchpad_y;
    Uint64 timestamp = SDL_GetTicksNS();

    SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_SHIELD_V103_TOUCHPAD, (data[1] & 0x01) ? SDL_PRESSED : SDL_RELEASED);

    /* It's a triangular pad, but just use the center as the usable touch area */
    touchpad_state = ((data[1] & 0x80) == 0) ? SDL_PRESSED : SDL_RELEASED;
    touchpad_x = clamp((float)(data[2] - 0x70) / 0x50, 0.0f, 1.0f);
    touchpad_y = clamp((float)(data[4] - 0x40) / 0x15, 0.0f, 1.0f);
    SDL_PrivateJoystickTouchpad(timestamp, joystick, 0, 0, touchpad_state, touchpad_x, touchpad_y, touchpad_state ? 1.0f : 0.0f);
}

static void HIDAPI_DriverShield_HandleStatePacketV104(SDL_Joystick *joystick, SDL_DriverShield_Context *ctx, Uint8 *data, int size)
{
    Uint64 timestamp = SDL_GetTicksNS();

    if (size < 23) {
        return;
    }

    if (ctx->last_state[2] != data[2]) {
        SDL_bool dpad_up = SDL_FALSE;
        SDL_bool dpad_down = SDL_FALSE;
        SDL_bool dpad_left = SDL_FALSE;
        SDL_bool dpad_right = SDL_FALSE;

        switch (data[2]) {
        case 0:
            dpad_up = SDL_TRUE;
            break;
        case 1:
            dpad_up = SDL_TRUE;
            dpad_right = SDL_TRUE;
            break;
        case 2:
            dpad_right = SDL_TRUE;
            break;
        case 3:
            dpad_right = SDL_TRUE;
            dpad_down = SDL_TRUE;
            break;
        case 4:
            dpad_down = SDL_TRUE;
            break;
        case 5:
            dpad_left = SDL_TRUE;
            dpad_down = SDL_TRUE;
            break;
        case 6:
            dpad_left = SDL_TRUE;
            break;
        case 7:
            dpad_up = SDL_TRUE;
            dpad_left = SDL_TRUE;
            break;
        default:
            break;
        }
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_DPAD_DOWN, dpad_down);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_DPAD_UP, dpad_up);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_DPAD_RIGHT, dpad_right);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_DPAD_LEFT, dpad_left);
    }

    if (ctx->last_state[3] != data[3]) {
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_A, (data[3] & 0x01) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_B, (data[3] & 0x02) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_X, (data[3] & 0x04) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_Y, (data[3] & 0x08) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_LEFTSHOULDER, (data[3] & 0x10) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_RIGHTSHOULDER, (data[3] & 0x20) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_LEFTSTICK, (data[3] & 0x40) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_RIGHTSTICK, (data[3] & 0x80) ? SDL_PRESSED : SDL_RELEASED);
    }

    if (ctx->last_state[4] != data[4]) {
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_START, (data[4] & 0x01) ? SDL_PRESSED : SDL_RELEASED);
    }

    SDL_PrivateJoystickAxis(timestamp, joystick, SDL_CONTROLLER_AXIS_LEFTX, SDL_SwapLE16(*(Sint16 *)&data[9]) - 0x8000);
    SDL_PrivateJoystickAxis(timestamp, joystick, SDL_CONTROLLER_AXIS_LEFTY, SDL_SwapLE16(*(Sint16 *)&data[11]) - 0x8000);

    SDL_PrivateJoystickAxis(timestamp, joystick, SDL_CONTROLLER_AXIS_RIGHTX, SDL_SwapLE16(*(Sint16 *)&data[13]) - 0x8000);
    SDL_PrivateJoystickAxis(timestamp, joystick, SDL_CONTROLLER_AXIS_RIGHTY, SDL_SwapLE16(*(Sint16 *)&data[15]) - 0x8000);

    SDL_PrivateJoystickAxis(timestamp, joystick, SDL_CONTROLLER_AXIS_TRIGGERLEFT, SDL_SwapLE16(*(Sint16 *)&data[19]) - 0x8000);
    SDL_PrivateJoystickAxis(timestamp, joystick, SDL_CONTROLLER_AXIS_TRIGGERRIGHT, SDL_SwapLE16(*(Sint16 *)&data[21]) - 0x8000);

    if (ctx->last_state[17] != data[17]) {
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_MISC1, (data[17] & 0x01) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_BACK, (data[17] & 0x02) ? SDL_PRESSED : SDL_RELEASED);
        SDL_PrivateJoystickButton(timestamp, joystick, SDL_CONTROLLER_BUTTON_GUIDE, (data[17] & 0x04) ? SDL_PRESSED : SDL_RELEASED);
    }

    SDL_memcpy(ctx->last_state, data, SDL_min(size, sizeof(ctx->last_state)));
}

static SDL_bool HIDAPI_DriverShield_UpdateDevice(SDL_HIDAPI_Device *device)
{
    SDL_DriverShield_Context *ctx = (SDL_DriverShield_Context *)device->context;
    SDL_Joystick *joystick = NULL;
    Uint8 data[USB_PACKET_LENGTH];
    int size = 0;
    ShieldCommandReport_t *cmd_resp_report;

    if (device->num_joysticks > 0) {
        joystick = SDL_JoystickFromInstanceID(device->joysticks[0]);
    } else {
        return SDL_FALSE;
    }

    while ((size = SDL_hid_read_timeout(device->dev, data, sizeof(data), 0)) > 0) {
#ifdef DEBUG_SHIELD_PROTOCOL
        HIDAPI_DumpPacket("NVIDIA SHIELD packet: size = %d", data, size);
#endif

        /* Byte 0 is HID report ID */
        switch (data[0]) {
        case k_ShieldReportIdControllerState:
            if (joystick == NULL) {
                break;
            }
            if (size == 16) {
                HIDAPI_DriverShield_HandleStatePacketV103(joystick, ctx, data, size);
            } else {
                HIDAPI_DriverShield_HandleStatePacketV104(joystick, ctx, data, size);
            }
            break;
        case k_ShieldReportIdControllerTouch:
            if (joystick == NULL) {
                break;
            }
            HIDAPI_DriverShield_HandleTouchPacketV103(joystick, ctx, data, size);
            break;
        case k_ShieldReportIdCommandResponse:
            cmd_resp_report = (ShieldCommandReport_t *)data;
            switch (cmd_resp_report->cmd) {
            case CMD_RUMBLE:
                ctx->rumble_report_pending = SDL_FALSE;
                HIDAPI_DriverShield_SendNextRumble(device);
                break;
            case CMD_CHARGE_STATE:
                ctx->charging = cmd_resp_report->payload[0] != 0;
                if (joystick) {
                    SDL_PrivateJoystickBatteryLevel(joystick, ctx->charging ? SDL_JOYSTICK_POWER_WIRED : ctx->battery_level);
                }
                break;
            case CMD_BATTERY_STATE:
                switch (cmd_resp_report->payload[2]) {
                case 0:
                    ctx->battery_level = SDL_JOYSTICK_POWER_EMPTY;
                    break;
                case 1:
                    ctx->battery_level = SDL_JOYSTICK_POWER_LOW;
                    break;
                case 2: /* 40% */
                case 3: /* 60% */
                case 4: /* 80% */
                    ctx->battery_level = SDL_JOYSTICK_POWER_MEDIUM;
                    break;
                case 5:
                    ctx->battery_level = SDL_JOYSTICK_POWER_FULL;
                    break;
                default:
                    ctx->battery_level = SDL_JOYSTICK_POWER_UNKNOWN;
                    break;
                }
                if (joystick) {
                    SDL_PrivateJoystickBatteryLevel(joystick, ctx->charging ? SDL_JOYSTICK_POWER_WIRED : ctx->battery_level);
                }
                break;
            }
            break;
        }
    }

    /* Ask for battery state again if we're due for an update */
    if (joystick && SDL_GetTicks() >= (ctx->last_battery_query_time + BATTERY_POLL_INTERVAL_MS)) {
        ctx->last_battery_query_time = SDL_GetTicks();
        HIDAPI_DriverShield_SendCommand(device, CMD_BATTERY_STATE, NULL, 0);
    }

    /* Retransmit rumble packets if they've lasted longer than the hardware supports */
    if ((ctx->left_motor_amplitude != 0 || ctx->right_motor_amplitude != 0) &&
        SDL_GetTicks() >= (ctx->last_rumble_time + RUMBLE_REFRESH_INTERVAL_MS)) {
        ctx->rumble_update_pending = SDL_TRUE;
        HIDAPI_DriverShield_SendNextRumble(device);
    }

    if (size < 0) {
        /* Read error, device is disconnected */
        HIDAPI_JoystickDisconnected(device, device->joysticks[0]);
    }
    return size >= 0;
}

static void HIDAPI_DriverShield_CloseJoystick(SDL_HIDAPI_Device *device, SDL_Joystick *joystick)
{
}

static void HIDAPI_DriverShield_FreeDevice(SDL_HIDAPI_Device *device)
{
}

SDL_HIDAPI_DeviceDriver SDL_HIDAPI_DriverShield = {
    SDL_HINT_JOYSTICK_HIDAPI_SHIELD,
    SDL_TRUE,
    HIDAPI_DriverShield_RegisterHints,
    HIDAPI_DriverShield_UnregisterHints,
    HIDAPI_DriverShield_IsEnabled,
    HIDAPI_DriverShield_IsSupportedDevice,
    HIDAPI_DriverShield_InitDevice,
    HIDAPI_DriverShield_GetDevicePlayerIndex,
    HIDAPI_DriverShield_SetDevicePlayerIndex,
    HIDAPI_DriverShield_UpdateDevice,
    HIDAPI_DriverShield_OpenJoystick,
    HIDAPI_DriverShield_RumbleJoystick,
    HIDAPI_DriverShield_RumbleJoystickTriggers,
    HIDAPI_DriverShield_GetJoystickCapabilities,
    HIDAPI_DriverShield_SetJoystickLED,
    HIDAPI_DriverShield_SendJoystickEffect,
    HIDAPI_DriverShield_SetJoystickSensorsEnabled,
    HIDAPI_DriverShield_CloseJoystick,
    HIDAPI_DriverShield_FreeDevice,
};

#endif /* SDL_JOYSTICK_HIDAPI_SHIELD */

#endif /* SDL_JOYSTICK_HIDAPI */

/* vi: set ts=4 sw=4 expandtab: */