include/Android/hardware/hardware.h

/*
 * Copyright (C) 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#pragma once

#include <cstdint>

#define MAKE_TAG_CONSTANT(A, B, C, D) (((A) << 24) | ((B) << 16) | ((C) << 8) | (D))

#define HARDWARE_MODULE_TAG MAKE_TAG_CONSTANT('H', 'W', 'M', 'T')
#define HARDWARE_DEVICE_TAG MAKE_TAG_CONSTANT('H', 'W', 'D', 'T')

#define HARDWARE_MAKE_API_VERSION(maj, min) ((((maj)&0xff) << 8) | ((min)&0xff))

#define HARDWARE_HAL_API_VERSION HARDWARE_MAKE_API_VERSION(1, 0)

struct hw_module_methods_t;

struct hw_module_t {
    uint32_t tag;
    uint16_t module_api_version;
    uint16_t hal_api_version;
    const char* id;
    const char* name;
    const char* author;
    hw_module_methods_t* methods;
    void* dso;
#ifdef __LP64__
    uint64_t reserved[32 - 7];
#else
    uint32_t reserved[32 - 7];
#endif
};

struct hw_device_t {
    uint32_t tag;
    uint32_t version;
    struct hw_module_t* module;
#ifdef __LP64__
    uint64_t reserved[12];
#else
    uint32_t reserved[12];
#endif
    int (*close)(hw_device_t* device);
};

struct hw_module_methods_t {
    int (*open)(const hw_module_t*, const char*, hw_device_t**);
};

extern "C" {
int hw_get_module(const char* id, const hw_module_t** module);
};