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 18 #ifndef ANDROID_GRALLOC_INTERFACE_H 19 #define ANDROID_GRALLOC_INTERFACE_H 20 21 #include <cutils/native_handle.h> 22 23 #include <hardware/hardware.h> 24 25 #include <stdint.h> 26 #include <sys/cdefs.h> 27 #include <sys/types.h> 28 29 __BEGIN_DECLS 30 31 /** 32 * The id of this module 33 */ 34 #define GRALLOC_HARDWARE_MODULE_ID "gralloc" 35 36 /** 37 * Name of the graphics device to open 38 */ 39 40 #define GRALLOC_HARDWARE_FB0 "fb0" 41 #define GRALLOC_HARDWARE_GPU0 "gpu0" 42 43 enum { 44 /* buffer is never read in software */ 45 GRALLOC_USAGE_SW_READ_NEVER = 0x00000000, 46 /* buffer is rarely read in software */ 47 GRALLOC_USAGE_SW_READ_RARELY = 0x00000002, 48 /* buffer is often read in software */ 49 GRALLOC_USAGE_SW_READ_OFTEN = 0x00000003, 50 /* mask for the software read values */ 51 GRALLOC_USAGE_SW_READ_MASK = 0x0000000F, 52 53 /* buffer is never written in software */ 54 GRALLOC_USAGE_SW_WRITE_NEVER = 0x00000000, 55 /* buffer is never written in software */ 56 GRALLOC_USAGE_SW_WRITE_RARELY = 0x00000020, 57 /* buffer is never written in software */ 58 GRALLOC_USAGE_SW_WRITE_OFTEN = 0x00000030, 59 /* mask for the software write values */ 60 GRALLOC_USAGE_SW_WRITE_MASK = 0x000000F0, 61 62 /* buffer will be used as an OpenGL ES texture */ 63 GRALLOC_USAGE_HW_TEXTURE = 0x00000100, 64 /* buffer will be used as an OpenGL ES render target */ 65 GRALLOC_USAGE_HW_RENDER = 0x00000200, 66 /* buffer will be used by the 2D hardware blitter */ 67 GRALLOC_USAGE_HW_2D = 0x00000C00, 68 /* buffer will be used with the framebuffer device */ 69 GRALLOC_USAGE_HW_FB = 0x00001000, 70 /* mask for the software usage bit-mask */ 71 GRALLOC_USAGE_HW_MASK = 0x00001F00, 72 }; 73 74 /*****************************************************************************/ 75 76 typedef const native_handle* buffer_handle_t; 77 78 enum { 79 /* FIXME: this only exists to work-around some issues with 80 * the video and camera frameworks. don't implement unless 81 * you know what you're doing. 82 */ 83 GRALLOC_MODULE_PERFORM_CREATE_HANDLE_FROM_BUFFER = 0x080000001, 84 }; 85 86 /** 87 * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM 88 * and the fields of this data structure must begin with hw_module_t 89 * followed by module specific information. 90 */ 91 typedef struct gralloc_module_t { 92 struct hw_module_t common; 93 94 /* 95 * (*registerBuffer)() must be called before a buffer_handle_t that has not 96 * been created with (*alloc_device_t::alloc)() can be used. 97 * 98 * This is intended to be used with buffer_handle_t's that have been 99 * received in this process through IPC. 100 * 101 * This function checks that the handle is indeed a valid one and prepares 102 * it for use with (*lock)() and (*unlock)(). 103 * 104 * It is not necessary to call (*registerBuffer)() on a handle created 105 * with (*alloc_device_t::alloc)(). 106 * 107 * returns an error if this buffer_handle_t is not valid. 108 */ 109 int (*registerBuffer)(struct gralloc_module_t const* module, 110 buffer_handle_t handle); 111 112 /* 113 * (*unregisterBuffer)() is called once this handle is no longer needed in 114 * this process. After this call, it is an error to call (*lock)(), 115 * (*unlock)(), or (*registerBuffer)(). 116 * 117 * This function doesn't close or free the handle itself; this is done 118 * by other means, usually through libcutils's native_handle_close() and 119 * native_handle_free(). 120 * 121 * It is an error to call (*unregisterBuffer)() on a buffer that wasn't 122 * explicitly registered first. 123 */ 124 int (*unregisterBuffer)(struct gralloc_module_t const* module, 125 buffer_handle_t handle); 126 127 /* 128 * The (*lock)() method is called before a buffer is accessed for the 129 * specified usage. This call may block, for instance if the h/w needs 130 * to finish rendering or if CPU caches need to be synchronized. 131 * 132 * The caller promises to modify only pixels in the area specified 133 * by (l,t,w,h). 134 * 135 * The content of the buffer outside of the specified area is NOT modified 136 * by this call. 137 * 138 * If usage specifies GRALLOC_USAGE_SW_*, vaddr is filled with the address 139 * of the buffer in virtual memory. 140 * 141 * THREADING CONSIDERATIONS: 142 * 143 * It is legal for several different threads to lock a buffer from 144 * read access, none of the threads are blocked. 145 * 146 * However, locking a buffer simultaneously for write or read/write is 147 * undefined, but: 148 * - shall not result in termination of the process 149 * - shall not block the caller 150 * It is acceptable to return an error or to leave the buffer's content 151 * into an indeterminate state. 152 * 153 * If the buffer was created with a usage mask incompatible with the 154 * requested usage flags here, -EINVAL is returned. 155 * 156 */ 157 158 int (*lock)(struct gralloc_module_t const* module, 159 buffer_handle_t handle, int usage, 160 int l, int t, int w, int h, 161 void** vaddr); 162 163 164 /* 165 * The (*unlock)() method must be called after all changes to the buffer 166 * are completed. 167 */ 168 169 int (*unlock)(struct gralloc_module_t const* module, 170 buffer_handle_t handle); 171 172 173 /* reserved for future use */ 174 int (*perform)(struct gralloc_module_t const* module, 175 int operation, ... ); 176 177 /* reserved for future use */ 178 void* reserved_proc[7]; 179 } gralloc_module_t; 180 181 /*****************************************************************************/ 182 183 /** 184 * Every device data structure must begin with hw_device_t 185 * followed by module specific public methods and attributes. 186 */ 187 188 typedef struct alloc_device_t { 189 struct hw_device_t common; 190 191 /* 192 * (*alloc)() Allocates a buffer in graphic memory with the requested 193 * parameters and returns a buffer_handle_t and the stride in pixels to 194 * allow the implementation to satisfy hardware constraints on the width 195 * of a pixmap (eg: it may have to be multiple of 8 pixels). 196 * The CALLER TAKES OWNERSHIP of the buffer_handle_t. 197 * 198 * Returns 0 on success or -errno on error. 199 */ 200 201 int (*alloc)(struct alloc_device_t* dev, 202 int w, int h, int format, int usage, 203 buffer_handle_t* handle, int* stride); 204 205 /* 206 * (*free)() Frees a previously allocated buffer. 207 * Behavior is undefined if the buffer is still mapped in any process, 208 * but shall not result in termination of the program or security breaches 209 * (allowing a process to get access to another process' buffers). 210 * THIS FUNCTION TAKES OWNERSHIP of the buffer_handle_t which becomes 211 * invalid after the call. 212 * 213 * Returns 0 on success or -errno on error. 214 */ 215 int (*free)(struct alloc_device_t* dev, 216 buffer_handle_t handle); 217 218 } alloc_device_t; 219 220 221 typedef struct framebuffer_device_t { 222 struct hw_device_t common; 223 224 /* flags describing some attributes of the framebuffer */ 225 const uint32_t flags; 226 227 /* dimensions of the framebuffer in pixels */ 228 const uint32_t width; 229 const uint32_t height; 230 231 /* frambuffer stride in pixels */ 232 const int stride; 233 234 /* framebuffer pixel format */ 235 const int format; 236 237 /* resolution of the framebuffer's display panel in pixel per inch*/ 238 const float xdpi; 239 const float ydpi; 240 241 /* framebuffer's display panel refresh rate in frames per second */ 242 const float fps; 243 244 /* min swap interval supported by this framebuffer */ 245 const int minSwapInterval; 246 247 /* max swap interval supported by this framebuffer */ 248 const int maxSwapInterval; 249 250 int reserved[8]; 251 252 /* 253 * requests a specific swap-interval (same definition than EGL) 254 * 255 * Returns 0 on success or -errno on error. 256 */ 257 int (*setSwapInterval)(struct framebuffer_device_t* window, 258 int interval); 259 260 /* 261 * This hook is OPTIONAL. 262 * 263 * It is non NULL If the framebuffer driver supports "update-on-demand" 264 * and the given rectangle is the area of the screen that gets 265 * updated during (*post)(). 266 * 267 * This is useful on devices that are able to DMA only a portion of 268 * the screen to the display panel, upon demand -- as opposed to 269 * constantly refreshing the panel 60 times per second, for instance. 270 * 271 * Only the area defined by this rectangle is guaranteed to be valid, that 272 * is, the driver is not allowed to post anything outside of this 273 * rectangle. 274 * 275 * The rectangle evaluated during (*post)() and specifies which area 276 * of the buffer passed in (*post)() shall to be posted. 277 * 278 * return -EINVAL if width or height <=0, or if left or top < 0 279 */ 280 int (*setUpdateRect)(struct framebuffer_device_t* window, 281 int left, int top, int width, int height); 282 283 /* 284 * Post <buffer> to the display (display it on the screen) 285 * The buffer must have been allocated with the 286 * GRALLOC_USAGE_HW_FB usage flag. 287 * buffer must be the same width and height as the display and must NOT 288 * be locked. 289 * 290 * The buffer is shown during the next VSYNC. 291 * 292 * If the same buffer is posted again (possibly after some other buffer), 293 * post() will block until the the first post is completed. 294 * 295 * Internally, post() is expected to lock the buffer so that a 296 * subsequent call to gralloc_module_t::(*lock)() with USAGE_RENDER or 297 * USAGE_*_WRITE will block until it is safe; that is typically once this 298 * buffer is shown and another buffer has been posted. 299 * 300 * Returns 0 on success or -errno on error. 301 */ 302 int (*post)(struct framebuffer_device_t* dev, buffer_handle_t buffer); 303 304 305 /* 306 * The (*compositionComplete)() method must be called after the 307 * compositor has finished issuing GL commands for client buffers. 308 */ 309 310 int (*compositionComplete)(struct framebuffer_device_t* dev); 311 312 313 void* reserved_proc[8]; 314 315 } framebuffer_device_t; 316 317 318 /** convenience API for opening and closing a supported device */ 319 320 static inline int gralloc_open(const struct hw_module_t* module, 321 struct alloc_device_t** device) { 322 return module->methods->open(module, 323 GRALLOC_HARDWARE_GPU0, (struct hw_device_t**)device); 324 } 325 326 static inline int gralloc_close(struct alloc_device_t* device) { 327 return device->common.close(&device->common); 328 } 329 330 331 static inline int framebuffer_open(const struct hw_module_t* module, 332 struct framebuffer_device_t** device) { 333 return module->methods->open(module, 334 GRALLOC_HARDWARE_FB0, (struct hw_device_t**)device); 335 } 336 337 static inline int framebuffer_close(struct framebuffer_device_t* device) { 338 return device->common.close(&device->common); 339 } 340 341 342 __END_DECLS 343 344 #endif // ANDROID_ALLOC_INTERFACE_H 345