gralloc.h revision 53b8af5e9ccb7ab9b48b223d4efde9096890fd6a 
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
100/**
101 * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM
102 * and the fields of this data structure must begin with hw_module_t
103 * followed by module specific information.
104 */
105typedef struct gralloc_module_t {
106    struct hw_module_t common;
107
108    /*
109     * (*registerBuffer)() must be called before a buffer_handle_t that has not
110     * been created with (*alloc_device_t::alloc)() can be used.
111     *
112     * This is intended to be used with buffer_handle_t's that have been
113     * received in this process through IPC.
114     *
115     * This function checks that the handle is indeed a valid one and prepares
116     * it for use with (*lock)() and (*unlock)().
117     *
118     * It is not necessary to call (*registerBuffer)() on a handle created
119     * with (*alloc_device_t::alloc)().
120     *
121     * returns an error if this buffer_handle_t is not valid.
122     */
123    int (*registerBuffer)(struct gralloc_module_t const* module,
124            buffer_handle_t handle);
125
126    /*
127     * (*unregisterBuffer)() is called once this handle is no longer needed in
128     * this process. After this call, it is an error to call (*lock)(),
129     * (*unlock)(), or (*registerBuffer)().
130     *
131     * This function doesn't close or free the handle itself; this is done
132     * by other means, usually through libcutils's native_handle_close() and
133     * native_handle_free().
134     *
135     * It is an error to call (*unregisterBuffer)() on a buffer that wasn't
136     * explicitly registered first.
137     */
138    int (*unregisterBuffer)(struct gralloc_module_t const* module,
139            buffer_handle_t handle);
140
141    /*
142     * The (*lock)() method is called before a buffer is accessed for the
143     * specified usage. This call may block, for instance if the h/w needs
144     * to finish rendering or if CPU caches need to be synchronized.
145     *
146     * The caller promises to modify only pixels in the area specified
147     * by (l,t,w,h).
148     *
149     * The content of the buffer outside of the specified area is NOT modified
150     * by this call.
151     *
152     * If usage specifies GRALLOC_USAGE_SW_*, vaddr is filled with the address
153     * of the buffer in virtual memory.
154     *
155     * THREADING CONSIDERATIONS:
156     *
157     * It is legal for several different threads to lock a buffer from
158     * read access, none of the threads are blocked.
159     *
160     * However, locking a buffer simultaneously for write or read/write is
161     * undefined, but:
162     * - shall not result in termination of the process
163     * - shall not block the caller
164     * It is acceptable to return an error or to leave the buffer's content
165     * into an indeterminate state.
166     *
167     * If the buffer was created with a usage mask incompatible with the
168     * requested usage flags here, -EINVAL is returned.
169     *
170     */
171
172    int (*lock)(struct gralloc_module_t const* module,
173            buffer_handle_t handle, int usage,
174            int l, int t, int w, int h,
175            void** vaddr);
176
177
178    /*
179     * The (*unlock)() method must be called after all changes to the buffer
180     * are completed.
181     */
182
183    int (*unlock)(struct gralloc_module_t const* module,
184            buffer_handle_t handle);
185
186
187    /* reserved for future use */
188    int (*perform)(struct gralloc_module_t const* module,
189            int operation, ... );
190
191    /* reserved for future use */
192    void* reserved_proc[7];
193} gralloc_module_t;
194
195/*****************************************************************************/
196
197/**
198 * Every device data structure must begin with hw_device_t
199 * followed by module specific public methods and attributes.
200 */
201
202typedef struct alloc_device_t {
203    struct hw_device_t common;
204
205    /*
206     * (*alloc)() Allocates a buffer in graphic memory with the requested
207     * parameters and returns a buffer_handle_t and the stride in pixels to
208     * allow the implementation to satisfy hardware constraints on the width
209     * of a pixmap (eg: it may have to be multiple of 8 pixels).
210     * The CALLER TAKES OWNERSHIP of the buffer_handle_t.
211     *
212     * Returns 0 on success or -errno on error.
213     */
214
215    int (*alloc)(struct alloc_device_t* dev,
216            int w, int h, int format, int usage,
217            buffer_handle_t* handle, int* stride);
218
219    /*
220     * (*free)() Frees a previously allocated buffer.
221     * Behavior is undefined if the buffer is still mapped in any process,
222     * but shall not result in termination of the program or security breaches
223     * (allowing a process to get access to another process' buffers).
224     * THIS FUNCTION TAKES OWNERSHIP of the buffer_handle_t which becomes
225     * invalid after the call.
226     *
227     * Returns 0 on success or -errno on error.
228     */
229    int (*free)(struct alloc_device_t* dev,
230            buffer_handle_t handle);
231
232    /* This hook is OPTIONAL.
233     *
234     * If non NULL it will be caused by SurfaceFlinger on dumpsys
235     */
236    void (*dump)(struct alloc_device_t *dev, char *buff, int buff_len);
237
238    void* reserved_proc[7];
239} alloc_device_t;
240
241
242typedef struct framebuffer_device_t {
243    struct hw_device_t common;
244
245    /* flags describing some attributes of the framebuffer */
246    const uint32_t  flags;
247
248    /* dimensions of the framebuffer in pixels */
249    const uint32_t  width;
250    const uint32_t  height;
251
252    /* frambuffer stride in pixels */
253    const int       stride;
254
255    /* framebuffer pixel format */
256    const int       format;
257
258    /* resolution of the framebuffer's display panel in pixel per inch*/
259    const float     xdpi;
260    const float     ydpi;
261
262    /* framebuffer's display panel refresh rate in frames per second */
263    const float     fps;
264
265    /* min swap interval supported by this framebuffer */
266    const int       minSwapInterval;
267
268    /* max swap interval supported by this framebuffer */
269    const int       maxSwapInterval;
270
271    int reserved[8];
272
273    /*
274     * requests a specific swap-interval (same definition than EGL)
275     *
276     * Returns 0 on success or -errno on error.
277     */
278    int (*setSwapInterval)(struct framebuffer_device_t* window,
279            int interval);
280
281    /*
282     * This hook is OPTIONAL.
283     *
284     * It is non NULL If the framebuffer driver supports "update-on-demand"
285     * and the given rectangle is the area of the screen that gets
286     * updated during (*post)().
287     *
288     * This is useful on devices that are able to DMA only a portion of
289     * the screen to the display panel, upon demand -- as opposed to
290     * constantly refreshing the panel 60 times per second, for instance.
291     *
292     * Only the area defined by this rectangle is guaranteed to be valid, that
293     * is, the driver is not allowed to post anything outside of this
294     * rectangle.
295     *
296     * The rectangle evaluated during (*post)() and specifies which area
297     * of the buffer passed in (*post)() shall to be posted.
298     *
299     * return -EINVAL if width or height <=0, or if left or top < 0
300     */
301    int (*setUpdateRect)(struct framebuffer_device_t* window,
302            int left, int top, int width, int height);
303
304    /*
305     * Post <buffer> to the display (display it on the screen)
306     * The buffer must have been allocated with the
307     *   GRALLOC_USAGE_HW_FB usage flag.
308     * buffer must be the same width and height as the display and must NOT
309     * be locked.
310     *
311     * The buffer is shown during the next VSYNC.
312     *
313     * If the same buffer is posted again (possibly after some other buffer),
314     * post() will block until the the first post is completed.
315     *
316     * Internally, post() is expected to lock the buffer so that a
317     * subsequent call to gralloc_module_t::(*lock)() with USAGE_RENDER or
318     * USAGE_*_WRITE will block until it is safe; that is typically once this
319     * buffer is shown and another buffer has been posted.
320     *
321     * Returns 0 on success or -errno on error.
322     */
323    int (*post)(struct framebuffer_device_t* dev, buffer_handle_t buffer);
324
325
326    /*
327     * The (*compositionComplete)() method must be called after the
328     * compositor has finished issuing GL commands for client buffers.
329     */
330
331    int (*compositionComplete)(struct framebuffer_device_t* dev);
332
333    /*
334     * This hook is OPTIONAL.
335     *
336     * If non NULL it will be caused by SurfaceFlinger on dumpsys
337     */
338    void (*dump)(struct framebuffer_device_t* dev, char *buff, int buff_len);
339
340    /*
341     * (*enableScreen)() is used to either blank (enable=0) or
342     * unblank (enable=1) the screen this framebuffer is attached to.
343     *
344     * Returns 0 on success or -errno on error.
345     */
346    int (*enableScreen)(struct framebuffer_device_t* dev, int enable);
347
348    void* reserved_proc[6];
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