gralloc.h revision 7cb277a5c26447df01196bb19650235603062e93 
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#define GRALLOC_API_VERSION 1
32
33/**
34 * The id of this module
35 */
36#define GRALLOC_HARDWARE_MODULE_ID "gralloc"
37
38/**
39 * Name of the graphics device to open
40 */
41
42#define GRALLOC_HARDWARE_FB0 "fb0"
43#define GRALLOC_HARDWARE_GPU0 "gpu0"
44
45enum {
46    /* buffer is never read in software */
47    GRALLOC_USAGE_SW_READ_NEVER   = 0x00000000,
48    /* buffer is rarely read in software */
49    GRALLOC_USAGE_SW_READ_RARELY  = 0x00000002,
50    /* buffer is often read in software */
51    GRALLOC_USAGE_SW_READ_OFTEN   = 0x00000003,
52    /* mask for the software read values */
53    GRALLOC_USAGE_SW_READ_MASK    = 0x0000000F,
54
55    /* buffer is never written in software */
56    GRALLOC_USAGE_SW_WRITE_NEVER  = 0x00000000,
57    /* buffer is never written in software */
58    GRALLOC_USAGE_SW_WRITE_RARELY = 0x00000020,
59    /* buffer is never written in software */
60    GRALLOC_USAGE_SW_WRITE_OFTEN  = 0x00000030,
61    /* mask for the software write values */
62    GRALLOC_USAGE_SW_WRITE_MASK   = 0x000000F0,
63
64    /* buffer will be used as an OpenGL ES texture */
65    GRALLOC_USAGE_HW_TEXTURE      = 0x00000100,
66    /* buffer will be used as an OpenGL ES render target */
67    GRALLOC_USAGE_HW_RENDER       = 0x00000200,
68    /* buffer will be used by the 2D hardware blitter */
69    GRALLOC_USAGE_HW_2D           = 0x00000400,
70    /* buffer will be used with the framebuffer device */
71    GRALLOC_USAGE_HW_FB           = 0x00001000,
72    /* mask for the software usage bit-mask */
73    GRALLOC_USAGE_HW_MASK         = 0x00001F00,
74
75    /* buffer should be displayed full-screen on an external display when
76     * possible
77     */
78    GRALLOC_USAGE_EXTERNAL_DISP   = 0x00002000,
79
80    /* Must have a hardware-protected path to external display sink for
81     * this buffer.  If a hardware-protected path is not available, then
82     * either don't composite only this buffer (preferred) to the
83     * external sink, or (less desirable) do not route the entire
84     * composition to the external sink.
85     */
86    GRALLOC_USAGE_PROTECTED       = 0x00004000,
87
88    /* implementation-specific private usage flags */
89    GRALLOC_USAGE_PRIVATE_0       = 0x10000000,
90    GRALLOC_USAGE_PRIVATE_1       = 0x20000000,
91    GRALLOC_USAGE_PRIVATE_2       = 0x40000000,
92    GRALLOC_USAGE_PRIVATE_3       = 0x80000000,
93    GRALLOC_USAGE_PRIVATE_MASK    = 0xF0000000,
94};
95
96/*****************************************************************************/
97
98typedef const native_handle* buffer_handle_t;
99
100enum {
101    /* FIXME: this only exists to work-around some issues with
102     * the video and camera frameworks. don't implement unless
103     * you know what you're doing.
104     */
105    GRALLOC_MODULE_PERFORM_CREATE_HANDLE_FROM_BUFFER = 0x080000001,
106};
107
108/**
109 * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM
110 * and the fields of this data structure must begin with hw_module_t
111 * followed by module specific information.
112 */
113typedef struct gralloc_module_t {
114    struct hw_module_t common;
115
116    /*
117     * (*registerBuffer)() must be called before a buffer_handle_t that has not
118     * been created with (*alloc_device_t::alloc)() can be used.
119     *
120     * This is intended to be used with buffer_handle_t's that have been
121     * received in this process through IPC.
122     *
123     * This function checks that the handle is indeed a valid one and prepares
124     * it for use with (*lock)() and (*unlock)().
125     *
126     * It is not necessary to call (*registerBuffer)() on a handle created
127     * with (*alloc_device_t::alloc)().
128     *
129     * returns an error if this buffer_handle_t is not valid.
130     */
131    int (*registerBuffer)(struct gralloc_module_t const* module,
132            buffer_handle_t handle);
133
134    /*
135     * (*unregisterBuffer)() is called once this handle is no longer needed in
136     * this process. After this call, it is an error to call (*lock)(),
137     * (*unlock)(), or (*registerBuffer)().
138     *
139     * This function doesn't close or free the handle itself; this is done
140     * by other means, usually through libcutils's native_handle_close() and
141     * native_handle_free().
142     *
143     * It is an error to call (*unregisterBuffer)() on a buffer that wasn't
144     * explicitly registered first.
145     */
146    int (*unregisterBuffer)(struct gralloc_module_t const* module,
147            buffer_handle_t handle);
148
149    /*
150     * The (*lock)() method is called before a buffer is accessed for the
151     * specified usage. This call may block, for instance if the h/w needs
152     * to finish rendering or if CPU caches need to be synchronized.
153     *
154     * The caller promises to modify only pixels in the area specified
155     * by (l,t,w,h).
156     *
157     * The content of the buffer outside of the specified area is NOT modified
158     * by this call.
159     *
160     * If usage specifies GRALLOC_USAGE_SW_*, vaddr is filled with the address
161     * of the buffer in virtual memory.
162     *
163     * THREADING CONSIDERATIONS:
164     *
165     * It is legal for several different threads to lock a buffer from
166     * read access, none of the threads are blocked.
167     *
168     * However, locking a buffer simultaneously for write or read/write is
169     * undefined, but:
170     * - shall not result in termination of the process
171     * - shall not block the caller
172     * It is acceptable to return an error or to leave the buffer's content
173     * into an indeterminate state.
174     *
175     * If the buffer was created with a usage mask incompatible with the
176     * requested usage flags here, -EINVAL is returned.
177     *
178     */
179
180    int (*lock)(struct gralloc_module_t const* module,
181            buffer_handle_t handle, int usage,
182            int l, int t, int w, int h,
183            void** vaddr);
184
185
186    /*
187     * The (*unlock)() method must be called after all changes to the buffer
188     * are completed.
189     */
190
191    int (*unlock)(struct gralloc_module_t const* module,
192            buffer_handle_t handle);
193
194
195    /* reserved for future use */
196    int (*perform)(struct gralloc_module_t const* module,
197            int operation, ... );
198
199    /* reserved for future use */
200    void* reserved_proc[7];
201} gralloc_module_t;
202
203/*****************************************************************************/
204
205/**
206 * Every device data structure must begin with hw_device_t
207 * followed by module specific public methods and attributes.
208 */
209
210typedef struct alloc_device_t {
211    struct hw_device_t common;
212
213    /*
214     * (*alloc)() Allocates a buffer in graphic memory with the requested
215     * parameters and returns a buffer_handle_t and the stride in pixels to
216     * allow the implementation to satisfy hardware constraints on the width
217     * of a pixmap (eg: it may have to be multiple of 8 pixels).
218     * The CALLER TAKES OWNERSHIP of the buffer_handle_t.
219     *
220     * Returns 0 on success or -errno on error.
221     */
222
223    int (*alloc)(struct alloc_device_t* dev,
224            int w, int h, int format, int usage,
225            buffer_handle_t* handle, int* stride);
226
227    /*
228     * (*free)() Frees a previously allocated buffer.
229     * Behavior is undefined if the buffer is still mapped in any process,
230     * but shall not result in termination of the program or security breaches
231     * (allowing a process to get access to another process' buffers).
232     * THIS FUNCTION TAKES OWNERSHIP of the buffer_handle_t which becomes
233     * invalid after the call.
234     *
235     * Returns 0 on success or -errno on error.
236     */
237    int (*free)(struct alloc_device_t* dev,
238            buffer_handle_t handle);
239
240    /* This hook is OPTIONAL.
241     *
242     * If non NULL it will be caused by SurfaceFlinger on dumpsys
243     */
244    void (*dump)(struct alloc_device_t *dev, char *buff, int buff_len);
245
246    void* reserved_proc[7];
247} alloc_device_t;
248
249
250typedef struct framebuffer_device_t {
251    struct hw_device_t common;
252
253    /* flags describing some attributes of the framebuffer */
254    const uint32_t  flags;
255
256    /* dimensions of the framebuffer in pixels */
257    const uint32_t  width;
258    const uint32_t  height;
259
260    /* frambuffer stride in pixels */
261    const int       stride;
262
263    /* framebuffer pixel format */
264    const int       format;
265
266    /* resolution of the framebuffer's display panel in pixel per inch*/
267    const float     xdpi;
268    const float     ydpi;
269
270    /* framebuffer's display panel refresh rate in frames per second */
271    const float     fps;
272
273    /* min swap interval supported by this framebuffer */
274    const int       minSwapInterval;
275
276    /* max swap interval supported by this framebuffer */
277    const int       maxSwapInterval;
278
279    int reserved[8];
280
281    /*
282     * requests a specific swap-interval (same definition than EGL)
283     *
284     * Returns 0 on success or -errno on error.
285     */
286    int (*setSwapInterval)(struct framebuffer_device_t* window,
287            int interval);
288
289    /*
290     * This hook is OPTIONAL.
291     *
292     * It is non NULL If the framebuffer driver supports "update-on-demand"
293     * and the given rectangle is the area of the screen that gets
294     * updated during (*post)().
295     *
296     * This is useful on devices that are able to DMA only a portion of
297     * the screen to the display panel, upon demand -- as opposed to
298     * constantly refreshing the panel 60 times per second, for instance.
299     *
300     * Only the area defined by this rectangle is guaranteed to be valid, that
301     * is, the driver is not allowed to post anything outside of this
302     * rectangle.
303     *
304     * The rectangle evaluated during (*post)() and specifies which area
305     * of the buffer passed in (*post)() shall to be posted.
306     *
307     * return -EINVAL if width or height <=0, or if left or top < 0
308     */
309    int (*setUpdateRect)(struct framebuffer_device_t* window,
310            int left, int top, int width, int height);
311
312    /*
313     * Post <buffer> to the display (display it on the screen)
314     * The buffer must have been allocated with the
315     *   GRALLOC_USAGE_HW_FB usage flag.
316     * buffer must be the same width and height as the display and must NOT
317     * be locked.
318     *
319     * The buffer is shown during the next VSYNC.
320     *
321     * If the same buffer is posted again (possibly after some other buffer),
322     * post() will block until the the first post is completed.
323     *
324     * Internally, post() is expected to lock the buffer so that a
325     * subsequent call to gralloc_module_t::(*lock)() with USAGE_RENDER or
326     * USAGE_*_WRITE will block until it is safe; that is typically once this
327     * buffer is shown and another buffer has been posted.
328     *
329     * Returns 0 on success or -errno on error.
330     */
331    int (*post)(struct framebuffer_device_t* dev, buffer_handle_t buffer);
332
333
334    /*
335     * The (*compositionComplete)() method must be called after the
336     * compositor has finished issuing GL commands for client buffers.
337     */
338
339    int (*compositionComplete)(struct framebuffer_device_t* dev);
340
341    /*
342     * This hook is OPTIONAL.
343     *
344     * If non NULL it will be caused by SurfaceFlinger on dumpsys
345     */
346    void (*dump)(struct framebuffer_device_t* dev, char *buff, int buff_len);
347
348    void* reserved_proc[7];
349
350} framebuffer_device_t;
351
352
353/** convenience API for opening and closing a supported device */
354
355static inline int gralloc_open(const struct hw_module_t* module,
356        struct alloc_device_t** device) {
357    return module->methods->open(module,
358            GRALLOC_HARDWARE_GPU0, (struct hw_device_t**)device);
359}
360
361static inline int gralloc_close(struct alloc_device_t* device) {
362    return device->common.close(&device->common);
363}
364
365
366static inline int framebuffer_open(const struct hw_module_t* module,
367        struct framebuffer_device_t** device) {
368    return module->methods->open(module,
369            GRALLOC_HARDWARE_FB0, (struct hw_device_t**)device);
370}
371
372static inline int framebuffer_close(struct framebuffer_device_t* device) {
373    return device->common.close(&device->common);
374}
375
376
377__END_DECLS
378
379#endif  // ANDROID_ALLOC_INTERFACE_H
380