third_party/hwcplus/include/hardware/hardware.h

   1 /*
   2  * Copyright (C) 2008 The Android Open Source Project
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *      http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #ifndef ANDROID_INCLUDE_HARDWARE_HARDWARE_H
  18 #define ANDROID_INCLUDE_HARDWARE_HARDWARE_H
  19
  20 #include <stdint.h>
  21 #include <sys/cdefs.h>
  22
  23 #include <cutils/native_handle.h>
  24 #include <system/graphics.h>
  25
  26 __BEGIN_DECLS
  27
  28 /*
  29  * Value for the hw_module_t.tag field
  30  */
  31
  32 #define MAKE_TAG_CONSTANT(A,B,C,D) (((A) << 24) | ((B) << 16) | ((C) << 8) | (D))
  33
  34 #define HARDWARE_MODULE_TAG MAKE_TAG_CONSTANT('H', 'W', 'M', 'T')
  35 #define HARDWARE_DEVICE_TAG MAKE_TAG_CONSTANT('H', 'W', 'D', 'T')
  36
  37 #define HARDWARE_MAKE_API_VERSION(maj,min) \
  38             ((((maj) & 0xff) << 8) | ((min) & 0xff))
  39
  40 #define HARDWARE_MAKE_API_VERSION_2(maj,min,hdr) \
  41             ((((maj) & 0xff) << 24) | (((min) & 0xff) << 16) | ((hdr) & 0xffff))
  42 #define HARDWARE_API_VERSION_2_MAJ_MIN_MASK 0xffff0000
  43 #define HARDWARE_API_VERSION_2_HEADER_MASK  0x0000ffff
  44
  45
  46 /*
  47  * The current HAL API version.
  48  *
  49  * All module implementations must set the hw_module_t.hal_api_version field
  50  * to this value when declaring the module with HAL_MODULE_INFO_SYM.
  51  *
  52  * Note that previous implementations have always set this field to 0.
  53  * Therefore, libhardware HAL API will always consider versions 0.0 and 1.0
  54  * to be 100% binary compatible.
  55  *
  56  */
  57 #define HARDWARE_HAL_API_VERSION HARDWARE_MAKE_API_VERSION(1, 0)
  58
  59 /*
  60  * Helper macros for module implementors.
  61  *
  62  * The derived modules should provide convenience macros for supported
  63  * versions so that implementations can explicitly specify module/device
  64  * versions at definition time.
  65  *
  66  * Use this macro to set the hw_module_t.module_api_version field.
  67  */
  68 #define HARDWARE_MODULE_API_VERSION(maj,min) HARDWARE_MAKE_API_VERSION(maj,min)
  69 #define HARDWARE_MODULE_API_VERSION_2(maj,min,hdr) HARDWARE_MAKE_API_VERSION_2(maj,min,hdr)
  70
  71 /*
  72  * Use this macro to set the hw_device_t.version field
  73  */
  74 #define HARDWARE_DEVICE_API_VERSION(maj,min) HARDWARE_MAKE_API_VERSION(maj,min)
  75 #define HARDWARE_DEVICE_API_VERSION_2(maj,min,hdr) HARDWARE_MAKE_API_VERSION_2(maj,min,hdr)
  76
  77 struct hw_module_t;
  78 struct hw_module_methods_t;
  79 struct hw_device_t;
  80
  81 /**
  82  * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM
  83  * and the fields of this data structure must begin with hw_module_t
  84  * followed by module specific information.
  85  */
  86 typedef struct hw_module_t {
  87     /** tag must be initialized to HARDWARE_MODULE_TAG */
  88     uint32_t tag;
  89
  90     /**
  91      * The API version of the implemented module. The module owner is
  92      * responsible for updating the version when a module interface has
  93      * changed.
  94      *
  95      * The derived modules such as gralloc and audio own and manage this field.
  96      * The module user must interpret the version field to decide whether or
  97      * not to inter-operate with the supplied module implementation.
  98      * For example, SurfaceFlinger is responsible for making sure that
  99      * it knows how to manage different versions of the gralloc-module API,
 100      * and AudioFlinger must know how to do the same for audio-module API.
 101      *
 102      * The module API version should include a major and a minor component.
 103      * For example, version 1.0 could be represented as 0x0100. This format
 104      * implies that versions 0x0100-0x01ff are all API-compatible.
 105      *
 106      * In the future, libhardware will expose a hw_get_module_version()
 107      * (or equivalent) function that will take minimum/maximum supported
 108      * versions as arguments and would be able to reject modules with
 109      * versions outside of the supplied range.
 110      */
 111     uint16_t module_api_version;
 112 #define version_major module_api_version
 113     /**
 114      * version_major/version_minor defines are supplied here for temporary
 115      * source code compatibility. They will be removed in the next version.
 116      * ALL clients must convert to the new version format.
 117      */
 118
 119     /**
 120      * The API version of the HAL module interface. This is meant to
 121      * version the hw_module_t, hw_module_methods_t, and hw_device_t
 122      * structures and definitions.
 123      *
 124      * The HAL interface owns this field. Module users/implementations
 125      * must NOT rely on this value for version information.
 126      *
 127      * Presently, 0 is the only valid value.
 128      */
 129     uint16_t hal_api_version;
 130 #define version_minor hal_api_version
 131
 132     /** Identifier of module */
 133     const char *id;
 134
 135     /** Name of this module */
 136     const char *name;
 137
 138     /** Author/owner/implementor of the module */
 139     const char *author;
 140
 141     /** Modules methods */
 142     struct hw_module_methods_t* methods;
 143
 144     /** module's dso */
 145     void* dso;
 146
 147     /** padding to 128 bytes, reserved for future use */
 148     uint32_t reserved[32-7];
 149
 150 } hw_module_t;
 151
 152 typedef struct hw_module_methods_t {
 153     /** Open a specific device */
 154     int (*open)(const struct hw_module_t* module, const char* id,
 155             struct hw_device_t** device);
 156
 157 } hw_module_methods_t;
 158
 159 /**
 160  * Every device data structure must begin with hw_device_t
 161  * followed by module specific public methods and attributes.
 162  */
 163 typedef struct hw_device_t {
 164     /** tag must be initialized to HARDWARE_DEVICE_TAG */
 165     uint32_t tag;
 166
 167     /**
 168      * Version of the module-specific device API. This value is used by
 169      * the derived-module user to manage different device implementations.
 170      *
 171      * The module user is responsible for checking the module_api_version
 172      * and device version fields to ensure that the user is capable of
 173      * communicating with the specific module implementation.
 174      *
 175      * One module can support multiple devices with different versions. This
 176      * can be useful when a device interface changes in an incompatible way
 177      * but it is still necessary to support older implementations at the same
 178      * time. One such example is the Camera 2.0 API.
 179      *
 180      * This field is interpreted by the module user and is ignored by the
 181      * HAL interface itself.
 182      */
 183     uint32_t version;
 184
 185     /** reference to the module this device belongs to */
 186     struct hw_module_t* module;
 187
 188     /** padding reserved for future use */
 189     uint32_t reserved[12];
 190
 191     /** Close this device */
 192     int (*close)(struct hw_device_t* device);
 193
 194 } hw_device_t;
 195
 196 /**
 197  * Name of the hal_module_info
 198  */
 199 #define HAL_MODULE_INFO_SYM         HMI
 200
 201 /**
 202  * Name of the hal_module_info as a string
 203  */
 204 #define HAL_MODULE_INFO_SYM_AS_STR  "HMI"
 205
 206 /**
 207  * Get the module info associated with a module by id.
 208  *
 209  * @return: 0 == success, <0 == error and *module == NULL
 210  */
 211 int hw_get_module(const char *id, const struct hw_module_t **module);
 212
 213 /**
 214  * Get the module info associated with a module instance by class 'class_id'
 215  * and instance 'inst'.
 216  *
 217  * Some modules types necessitate multiple instances. For example audio supports
 218  * multiple concurrent interfaces and thus 'audio' is the module class
 219  * and 'primary' or 'a2dp' are module interfaces. This implies that the files
 220  * providing these modules would be named audio.primary.<variant>.so and
 221  * audio.a2dp.<variant>.so
 222  *
 223  * @return: 0 == success, <0 == error and *module == NULL
 224  */
 225 int hw_get_module_by_class(const char *class_id, const char *inst,
 226                            const struct hw_module_t **module);
 227
 228 /**
 229  * Provide a function to handle log messages.
 230  */
 231 typedef int (*hwcplus_log_fn_t)(int prio, const char* tag, const char* msg);
 232 void hwcplus_set_log_fn(hwcplus_log_fn_t fn);
 233
 234 __END_DECLS
 235
 236 #endif  /* ANDROID_INCLUDE_HARDWARE_HARDWARE_H */