gralloc.h
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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 <system/window.h>
22 #include <system/graphics.h>
23 #include <hardware/hardware.h>
24 
25 #include <stdint.h>
26 #include <sys/cdefs.h>
27 #include <sys/types.h>
28 
29 #include <cutils/native_handle.h>
30 
31 #include <hardware/hardware.h>
32 #include <hardware/fb.h>
33 
34 __BEGIN_DECLS
35 
36 /**
37  * Module versioning information for the Gralloc hardware module, based on
38  * gralloc_module_t.common.module_api_version.
39  *
40  * Version History:
41  *
42  * GRALLOC_MODULE_API_VERSION_0_1:
43  * Initial Gralloc hardware module API.
44  *
45  * GRALLOC_MODULE_API_VERSION_0_2:
46  * Add support for flexible YCbCr format with (*lock_ycbcr)() method.
47  *
48  * GRALLOC_MODULE_API_VERSION_0_3:
49  * Add support for fence passing to/from lock/unlock.
50  */
51 
52 #define GRALLOC_MODULE_API_VERSION_0_1 HARDWARE_MODULE_API_VERSION(0, 1)
53 #define GRALLOC_MODULE_API_VERSION_0_2 HARDWARE_MODULE_API_VERSION(0, 2)
54 #define GRALLOC_MODULE_API_VERSION_0_3 HARDWARE_MODULE_API_VERSION(0, 3)
55 
56 #define GRALLOC_DEVICE_API_VERSION_0_1 HARDWARE_DEVICE_API_VERSION(0, 1)
57 
58 /**
59  * The id of this module
60  */
61 #define GRALLOC_HARDWARE_MODULE_ID "gralloc"
62 
63 /**
64  * Name of the graphics device to open
65  */
66 
67 #define GRALLOC_HARDWARE_GPU0 "gpu0"
68 
69 enum {
70  /* buffer is never read in software */
72  /* buffer is rarely read in software */
74  /* buffer is often read in software */
76  /* mask for the software read values */
78 
79  /* buffer is never written in software */
81  /* buffer is rarely written in software */
83  /* buffer is often written in software */
85  /* mask for the software write values */
87 
88  /* buffer will be used as an OpenGL ES texture */
90  /* buffer will be used as an OpenGL ES render target */
92  /* buffer will be used by the 2D hardware blitter */
93  GRALLOC_USAGE_HW_2D = 0x00000400,
94  /* buffer will be used by the HWComposer HAL module */
96  /* buffer will be used with the framebuffer device */
97  GRALLOC_USAGE_HW_FB = 0x00001000,
98  /* buffer will be used with the HW video encoder */
100  /* buffer will be written by the HW camera pipeline */
102  /* buffer will be read by the HW camera pipeline */
104  /* buffer will be used as part of zero-shutter-lag queue */
106  /* mask for the camera access values */
108  /* mask for the software usage bit-mask */
109  GRALLOC_USAGE_HW_MASK = 0x00071F00,
110 
111  /* buffer will be used as a RenderScript Allocation */
113 
114  /* buffer should be displayed full-screen on an external display when
115  * possible
116  */
118 
119  /* Must have a hardware-protected path to external display sink for
120  * this buffer. If a hardware-protected path is not available, then
121  * either don't composite only this buffer (preferred) to the
122  * external sink, or (less desirable) do not route the entire
123  * composition to the external sink.
124  */
126 
127  /* buffer may be used as a cursor */
128  GRALLOC_USAGE_CURSOR = 0x00008000,
129 
130  /* implementation-specific private usage flags */
136 };
137 
138 /*****************************************************************************/
139 
140 /**
141  * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM
142  * and the fields of this data structure must begin with hw_module_t
143  * followed by module specific information.
144  */
145 typedef struct gralloc_module_t {
147 
148  /*
149  * (*registerBuffer)() must be called before a buffer_handle_t that has not
150  * been created with (*alloc_device_t::alloc)() can be used.
151  *
152  * This is intended to be used with buffer_handle_t's that have been
153  * received in this process through IPC.
154  *
155  * This function checks that the handle is indeed a valid one and prepares
156  * it for use with (*lock)() and (*unlock)().
157  *
158  * It is not necessary to call (*registerBuffer)() on a handle created
159  * with (*alloc_device_t::alloc)().
160  *
161  * returns an error if this buffer_handle_t is not valid.
162  */
163  int (*registerBuffer)(struct gralloc_module_t const* module,
164  buffer_handle_t handle);
165 
166  /*
167  * (*unregisterBuffer)() is called once this handle is no longer needed in
168  * this process. After this call, it is an error to call (*lock)(),
169  * (*unlock)(), or (*registerBuffer)().
170  *
171  * This function doesn't close or free the handle itself; this is done
172  * by other means, usually through libcutils's native_handle_close() and
173  * native_handle_free().
174  *
175  * It is an error to call (*unregisterBuffer)() on a buffer that wasn't
176  * explicitly registered first.
177  */
178  int (*unregisterBuffer)(struct gralloc_module_t const* module,
179  buffer_handle_t handle);
180 
181  /*
182  * The (*lock)() method is called before a buffer is accessed for the
183  * specified usage. This call may block, for instance if the h/w needs
184  * to finish rendering or if CPU caches need to be synchronized.
185  *
186  * The caller promises to modify only pixels in the area specified
187  * by (l,t,w,h).
188  *
189  * The content of the buffer outside of the specified area is NOT modified
190  * by this call.
191  *
192  * If usage specifies GRALLOC_USAGE_SW_*, vaddr is filled with the address
193  * of the buffer in virtual memory.
194  *
195  * Note calling (*lock)() on HAL_PIXEL_FORMAT_YCbCr_*_888 buffers will fail
196  * and return -EINVAL. These buffers must be locked with (*lock_ycbcr)()
197  * instead.
198  *
199  * THREADING CONSIDERATIONS:
200  *
201  * It is legal for several different threads to lock a buffer from
202  * read access, none of the threads are blocked.
203  *
204  * However, locking a buffer simultaneously for write or read/write is
205  * undefined, but:
206  * - shall not result in termination of the process
207  * - shall not block the caller
208  * It is acceptable to return an error or to leave the buffer's content
209  * into an indeterminate state.
210  *
211  * If the buffer was created with a usage mask incompatible with the
212  * requested usage flags here, -EINVAL is returned.
213  *
214  */
215 
216  int (*lock)(struct gralloc_module_t const* module,
217  buffer_handle_t handle, int usage,
218  int l, int t, int w, int h,
219  void** vaddr);
220 
221 
222  /*
223  * The (*unlock)() method must be called after all changes to the buffer
224  * are completed.
225  */
226 
227  int (*unlock)(struct gralloc_module_t const* module,
228  buffer_handle_t handle);
229 
230 
231  /* reserved for future use */
232  int (*perform)(struct gralloc_module_t const* module,
233  int operation, ... );
234 
235  /*
236  * The (*lock_ycbcr)() method is like the (*lock)() method, with the
237  * difference that it fills a struct ycbcr with a description of the buffer
238  * layout, and zeroes out the reserved fields.
239  *
240  * This will only work on buffers with HAL_PIXEL_FORMAT_YCbCr_*_888, and
241  * will return -EINVAL on any other buffer formats.
242  *
243  * Added in GRALLOC_MODULE_API_VERSION_0_2.
244  */
245 
246  int (*lock_ycbcr)(struct gralloc_module_t const* module,
247  buffer_handle_t handle, int usage,
248  int l, int t, int w, int h,
249  struct android_ycbcr *ycbcr);
250 
251  /*
252  * The (*lockAsync)() method is like the (*lock)() method except
253  * that the buffer's sync fence object is passed into the lock
254  * call instead of requiring the caller to wait for completion.
255  *
256  * The gralloc implementation takes ownership of the fenceFd and
257  * is responsible for closing it when no longer needed.
258  *
259  * Added in GRALLOC_MODULE_API_VERSION_0_3.
260  */
261  int (*lockAsync)(struct gralloc_module_t const* module,
262  buffer_handle_t handle, int usage,
263  int l, int t, int w, int h,
264  void** vaddr, int fenceFd);
265 
266  /*
267  * The (*unlockAsync)() method is like the (*unlock)() method
268  * except that a buffer sync fence object is returned from the
269  * lock call, representing the completion of any pending work
270  * performed by the gralloc implementation.
271  *
272  * The caller takes ownership of the fenceFd and is responsible
273  * for closing it when no longer needed.
274  *
275  * Added in GRALLOC_MODULE_API_VERSION_0_3.
276  */
277  int (*unlockAsync)(struct gralloc_module_t const* module,
278  buffer_handle_t handle, int* fenceFd);
279 
280  /*
281  * The (*lockAsync_ycbcr)() method is like the (*lock_ycbcr)()
282  * method except that the buffer's sync fence object is passed
283  * into the lock call instead of requiring the caller to wait for
284  * completion.
285  *
286  * The gralloc implementation takes ownership of the fenceFd and
287  * is responsible for closing it when no longer needed.
288  *
289  * Added in GRALLOC_MODULE_API_VERSION_0_3.
290  */
291  int (*lockAsync_ycbcr)(struct gralloc_module_t const* module,
292  buffer_handle_t handle, int usage,
293  int l, int t, int w, int h,
294  struct android_ycbcr *ycbcr, int fenceFd);
295 
296  /* reserved for future use */
297  void* reserved_proc[3];
299 
300 /*****************************************************************************/
301 
302 /**
303  * Every device data structure must begin with hw_device_t
304  * followed by module specific public methods and attributes.
305  */
306 
307 typedef struct alloc_device_t {
309 
310  /*
311  * (*alloc)() Allocates a buffer in graphic memory with the requested
312  * parameters and returns a buffer_handle_t and the stride in pixels to
313  * allow the implementation to satisfy hardware constraints on the width
314  * of a pixmap (eg: it may have to be multiple of 8 pixels).
315  * The CALLER TAKES OWNERSHIP of the buffer_handle_t.
316  *
317  * If format is HAL_PIXEL_FORMAT_YCbCr_420_888, the returned stride must be
318  * 0, since the actual strides are available from the android_ycbcr
319  * structure.
320  *
321  * Returns 0 on success or -errno on error.
322  */
323 
324  int (*alloc)(struct alloc_device_t* dev,
325  int w, int h, int format, int usage,
326  buffer_handle_t* handle, int* stride);
327 
328  /*
329  * (*free)() Frees a previously allocated buffer.
330  * Behavior is undefined if the buffer is still mapped in any process,
331  * but shall not result in termination of the program or security breaches
332  * (allowing a process to get access to another process' buffers).
333  * THIS FUNCTION TAKES OWNERSHIP of the buffer_handle_t which becomes
334  * invalid after the call.
335  *
336  * Returns 0 on success or -errno on error.
337  */
338  int (*free)(struct alloc_device_t* dev,
339  buffer_handle_t handle);
340 
341  /* This hook is OPTIONAL.
342  *
343  * If non NULL it will be caused by SurfaceFlinger on dumpsys
344  */
345  void (*dump)(struct alloc_device_t *dev, char *buff, int buff_len);
346 
347  void* reserved_proc[7];
349 
350 
351 /** convenience API for opening and closing a supported device */
352 
353 static inline int gralloc_open(const struct hw_module_t* module,
354  struct alloc_device_t** device) {
355  return module->methods->open(module,
356  GRALLOC_HARDWARE_GPU0, (struct hw_device_t**)device);
357 }
358 
359 static inline int gralloc_close(struct alloc_device_t* device) {
360  return device->common.close(&device->common);
361 }
362 
363 __END_DECLS
364 
365 #endif // ANDROID_GRALLOC_INTERFACE_H
void(* dump)(struct alloc_device_t *dev, char *buff, int buff_len)
Definition: gralloc.h:345
#define GRALLOC_HARDWARE_GPU0
Definition: gralloc.h:67
int(* open)(const struct hw_module_t *module, const char *id, struct hw_device_t **device)
Definition: hardware.h:158
int(* close)(struct hw_device_t *device)
Definition: hardware.h:200
int(* registerBuffer)(struct gralloc_module_t const *module, buffer_handle_t handle)
Definition: gralloc.h:163
int(* lock)(struct gralloc_module_t const *module, buffer_handle_t handle, int usage, int l, int t, int w, int h, void **vaddr)
Definition: gralloc.h:216
struct alloc_device_t alloc_device_t
struct gralloc_module_t gralloc_module_t
int(* alloc)(struct alloc_device_t *dev, int w, int h, int format, int usage, buffer_handle_t *handle, int *stride)
Definition: gralloc.h:324
int(* unregisterBuffer)(struct gralloc_module_t const *module, buffer_handle_t handle)
Definition: gralloc.h:178
int(* free)(struct alloc_device_t *dev, buffer_handle_t handle)
Definition: gralloc.h:338
void * reserved_proc[7]
Definition: gralloc.h:347
int(* perform)(struct gralloc_module_t const *module, int operation,...)
Definition: gralloc.h:232
int(* lockAsync)(struct gralloc_module_t const *module, buffer_handle_t handle, int usage, int l, int t, int w, int h, void **vaddr, int fenceFd)
Definition: gralloc.h:261
struct hw_module_methods_t * methods
Definition: hardware.h:142
void * reserved_proc[3]
Definition: gralloc.h:297
int(* lock_ycbcr)(struct gralloc_module_t const *module, buffer_handle_t handle, int usage, int l, int t, int w, int h, struct android_ycbcr *ycbcr)
Definition: gralloc.h:246
int(* unlockAsync)(struct gralloc_module_t const *module, buffer_handle_t handle, int *fenceFd)
Definition: gralloc.h:277
int(* lockAsync_ycbcr)(struct gralloc_module_t const *module, buffer_handle_t handle, int usage, int l, int t, int w, int h, struct android_ycbcr *ycbcr, int fenceFd)
Definition: gralloc.h:291
int(* unlock)(struct gralloc_module_t const *module, buffer_handle_t handle)
Definition: gralloc.h:227
struct hw_module_t common
Definition: gralloc.h:146
struct hw_device_t common
Definition: gralloc.h:308