gralloc.h revision 33c0fe022e166007547d9c7390e7e6dbba5122e7 
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 <hardware/hardware.h>
23
24#include <stdint.h>
25#include <sys/cdefs.h>
26#include <sys/types.h>
27
28__BEGIN_DECLS
29
30#define GRALLOC_API_VERSION 1
31
32/**
33 * The id of this module
34 */
35#define GRALLOC_HARDWARE_MODULE_ID "gralloc"
36
37/**
38 * Name of the graphics device to open
39 */
40
41#define GRALLOC_HARDWARE_FB0 "fb0"
42#define GRALLOC_HARDWARE_GPU0 "gpu0"
43
44enum {
45    /* buffer is never read in software */
46    GRALLOC_USAGE_SW_READ_NEVER   = 0x00000000,
47    /* buffer is rarely read in software */
48    GRALLOC_USAGE_SW_READ_RARELY  = 0x00000002,
49    /* buffer is often read in software */
50    GRALLOC_USAGE_SW_READ_OFTEN   = 0x00000003,
51    /* mask for the software read values */
52    GRALLOC_USAGE_SW_READ_MASK    = 0x0000000F,
53
54    /* buffer is never written in software */
55    GRALLOC_USAGE_SW_WRITE_NEVER  = 0x00000000,
56    /* buffer is never written in software */
57    GRALLOC_USAGE_SW_WRITE_RARELY = 0x00000020,
58    /* buffer is never written in software */
59    GRALLOC_USAGE_SW_WRITE_OFTEN  = 0x00000030,
60    /* mask for the software write values */
61    GRALLOC_USAGE_SW_WRITE_MASK   = 0x000000F0,
62
63    /* buffer will be used as an OpenGL ES texture */
64    GRALLOC_USAGE_HW_TEXTURE      = 0x00000100,
65    /* buffer will be used as an OpenGL ES render target */
66    GRALLOC_USAGE_HW_RENDER       = 0x00000200,
67    /* buffer will be used by the 2D hardware blitter */
68    GRALLOC_USAGE_HW_2D           = 0x00000400,
69    /* buffer will be used with the framebuffer device */
70    GRALLOC_USAGE_HW_FB           = 0x00001000,
71    /* mask for the software usage bit-mask */
72    GRALLOC_USAGE_HW_MASK         = 0x00001F00,
73
74    /* buffer should be displayed full-screen on an external display when
75     * possible
76     */
77    GRALLOC_USAGE_EXTERNAL_DISP   = 0x00002000,
78
79    /* Must have a hardware-protected path to external display sink for
80     * this buffer.  If a hardware-protected path is not available, then
81     * either don't composite only this buffer (preferred) to the
82     * external sink, or (less desirable) do not route the entire
83     * composition to the external sink.
84     */
85    GRALLOC_USAGE_PROTECTED       = 0x00004000,
86
87    /* implementation-specific private usage flags */
88    GRALLOC_USAGE_PRIVATE_0       = 0x10000000,
89    GRALLOC_USAGE_PRIVATE_1       = 0x20000000,
90    GRALLOC_USAGE_PRIVATE_2       = 0x40000000,
91    GRALLOC_USAGE_PRIVATE_3       = 0x80000000,
92    GRALLOC_USAGE_PRIVATE_MASK    = 0xF0000000,
93};
94
95/*****************************************************************************/
96
97/**
98 * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM
99 * and the fields of this data structure must begin with hw_module_t
100 * followed by module specific information.
101 */
102typedef struct gralloc_module_t {
103    struct hw_module_t common;
104
105    /*
106     * (*registerBuffer)() must be called before a buffer_handle_t that has not
107     * been created with (*alloc_device_t::alloc)() can be used.
108     *
109     * This is intended to be used with buffer_handle_t's that have been
110     * received in this process through IPC.
111     *
112     * This function checks that the handle is indeed a valid one and prepares
113     * it for use with (*lock)() and (*unlock)().
114     *
115     * It is not necessary to call (*registerBuffer)() on a handle created
116     * with (*alloc_device_t::alloc)().
117     *
118     * returns an error if this buffer_handle_t is not valid.
119     */
120    int (*registerBuffer)(struct gralloc_module_t const* module,
121            buffer_handle_t handle);
122
123    /*
124     * (*unregisterBuffer)() is called once this handle is no longer needed in
125     * this process. After this call, it is an error to call (*lock)(),
126     * (*unlock)(), or (*registerBuffer)().
127     *
128     * This function doesn't close or free the handle itself; this is done
129     * by other means, usually through libcutils's native_handle_close() and
130     * native_handle_free().
131     *
132     * It is an error to call (*unregisterBuffer)() on a buffer that wasn't
133     * explicitly registered first.
134     */
135    int (*unregisterBuffer)(struct gralloc_module_t const* module,
136            buffer_handle_t handle);
137
138    /*
139     * The (*lock)() method is called before a buffer is accessed for the
140     * specified usage. This call may block, for instance if the h/w needs
141     * to finish rendering or if CPU caches need to be synchronized.
142     *
143     * The caller promises to modify only pixels in the area specified
144     * by (l,t,w,h).
145     *
146     * The content of the buffer outside of the specified area is NOT modified
147     * by this call.
148     *
149     * If usage specifies GRALLOC_USAGE_SW_*, vaddr is filled with the address
150     * of the buffer in virtual memory.
151     *
152     * THREADING CONSIDERATIONS:
153     *
154     * It is legal for several different threads to lock a buffer from
155     * read access, none of the threads are blocked.
156     *
157     * However, locking a buffer simultaneously for write or read/write is
158     * undefined, but:
159     * - shall not result in termination of the process
160     * - shall not block the caller
161     * It is acceptable to return an error or to leave the buffer's content
162     * into an indeterminate state.
163     *
164     * If the buffer was created with a usage mask incompatible with the
165     * requested usage flags here, -EINVAL is returned.
166     *
167     */
168
169    int (*lock)(struct gralloc_module_t const* module,
170            buffer_handle_t handle, int usage,
171            int l, int t, int w, int h,
172            void** vaddr);
173
174
175    /*
176     * The (*unlock)() method must be called after all changes to the buffer
177     * are completed.
178     */
179
180    int (*unlock)(struct gralloc_module_t const* module,
181            buffer_handle_t handle);
182
183
184    /* reserved for future use */
185    int (*perform)(struct gralloc_module_t const* module,
186            int operation, ... );
187
188    /* reserved for future use */
189    void* reserved_proc[7];
190} gralloc_module_t;
191
192/*****************************************************************************/
193
194/**
195 * Every device data structure must begin with hw_device_t
196 * followed by module specific public methods and attributes.
197 */
198
199typedef struct alloc_device_t {
200    struct hw_device_t common;
201
202    /*
203     * (*alloc)() Allocates a buffer in graphic memory with the requested
204     * parameters and returns a buffer_handle_t and the stride in pixels to
205     * allow the implementation to satisfy hardware constraints on the width
206     * of a pixmap (eg: it may have to be multiple of 8 pixels).
207     * The CALLER TAKES OWNERSHIP of the buffer_handle_t.
208     *
209     * Returns 0 on success or -errno on error.
210     */
211
212    int (*alloc)(struct alloc_device_t* dev,
213            int w, int h, int format, int usage,
214            buffer_handle_t* handle, int* stride);
215
216    /*
217     * (*free)() Frees a previously allocated buffer.
218     * Behavior is undefined if the buffer is still mapped in any process,
219     * but shall not result in termination of the program or security breaches
220     * (allowing a process to get access to another process' buffers).
221     * THIS FUNCTION TAKES OWNERSHIP of the buffer_handle_t which becomes
222     * invalid after the call.
223     *
224     * Returns 0 on success or -errno on error.
225     */
226    int (*free)(struct alloc_device_t* dev,
227            buffer_handle_t handle);
228
229    /* This hook is OPTIONAL.
230     *
231     * If non NULL it will be caused by SurfaceFlinger on dumpsys
232     */
233    void (*dump)(struct alloc_device_t *dev, char *buff, int buff_len);
234
235    void* reserved_proc[7];
236} alloc_device_t;
237
238
239typedef struct framebuffer_device_t {
240    struct hw_device_t common;
241
242    /* flags describing some attributes of the framebuffer */
243    const uint32_t  flags;
244
245    /* dimensions of the framebuffer in pixels */
246    const uint32_t  width;
247    const uint32_t  height;
248
249    /* frambuffer stride in pixels */
250    const int       stride;
251
252    /* framebuffer pixel format */
253    const int       format;
254
255    /* resolution of the framebuffer's display panel in pixel per inch*/
256    const float     xdpi;
257    const float     ydpi;
258
259    /* framebuffer's display panel refresh rate in frames per second */
260    const float     fps;
261
262    /* min swap interval supported by this framebuffer */
263    const int       minSwapInterval;
264
265    /* max swap interval supported by this framebuffer */
266    const int       maxSwapInterval;
267
268    int reserved[8];
269
270    /*
271     * requests a specific swap-interval (same definition than EGL)
272     *
273     * Returns 0 on success or -errno on error.
274     */
275    int (*setSwapInterval)(struct framebuffer_device_t* window,
276            int interval);
277
278    /*
279     * This hook is OPTIONAL.
280     *
281     * It is non NULL If the framebuffer driver supports "update-on-demand"
282     * and the given rectangle is the area of the screen that gets
283     * updated during (*post)().
284     *
285     * This is useful on devices that are able to DMA only a portion of
286     * the screen to the display panel, upon demand -- as opposed to
287     * constantly refreshing the panel 60 times per second, for instance.
288     *
289     * Only the area defined by this rectangle is guaranteed to be valid, that
290     * is, the driver is not allowed to post anything outside of this
291     * rectangle.
292     *
293     * The rectangle evaluated during (*post)() and specifies which area
294     * of the buffer passed in (*post)() shall to be posted.
295     *
296     * return -EINVAL if width or height <=0, or if left or top < 0
297     */
298    int (*setUpdateRect)(struct framebuffer_device_t* window,
299            int left, int top, int width, int height);
300
301    /*
302     * Post <buffer> to the display (display it on the screen)
303     * The buffer must have been allocated with the
304     *   GRALLOC_USAGE_HW_FB usage flag.
305     * buffer must be the same width and height as the display and must NOT
306     * be locked.
307     *
308     * The buffer is shown during the next VSYNC.
309     *
310     * If the same buffer is posted again (possibly after some other buffer),
311     * post() will block until the the first post is completed.
312     *
313     * Internally, post() is expected to lock the buffer so that a
314     * subsequent call to gralloc_module_t::(*lock)() with USAGE_RENDER or
315     * USAGE_*_WRITE will block until it is safe; that is typically once this
316     * buffer is shown and another buffer has been posted.
317     *
318     * Returns 0 on success or -errno on error.
319     */
320    int (*post)(struct framebuffer_device_t* dev, buffer_handle_t buffer);
321
322
323    /*
324     * The (*compositionComplete)() method must be called after the
325     * compositor has finished issuing GL commands for client buffers.
326     */
327
328    int (*compositionComplete)(struct framebuffer_device_t* dev);
329
330    /*
331     * This hook is OPTIONAL.
332     *
333     * If non NULL it will be caused by SurfaceFlinger on dumpsys
334     */
335    void (*dump)(struct framebuffer_device_t* dev, char *buff, int buff_len);
336
337    /*
338     * (*enableScreen)() is used to either blank (enable=0) or
339     * unblank (enable=1) the screen this framebuffer is attached to.
340     *
341     * Returns 0 on success or -errno on error.
342     */
343    int (*enableScreen)(struct framebuffer_device_t* dev, int enable);
344
345    void* reserved_proc[6];
346
347} framebuffer_device_t;
348
349
350/** convenience API for opening and closing a supported device */
351
352static inline int gralloc_open(const struct hw_module_t* module,
353        struct alloc_device_t** device) {
354    return module->methods->open(module,
355            GRALLOC_HARDWARE_GPU0, (struct hw_device_t**)device);
356}
357
358static inline int gralloc_close(struct alloc_device_t* device) {
359    return device->common.close(&device->common);
360}
361
362
363static inline int framebuffer_open(const struct hw_module_t* module,
364        struct framebuffer_device_t** device) {
365    return module->methods->open(module,
366            GRALLOC_HARDWARE_FB0, (struct hw_device_t**)device);
367}
368
369static inline int framebuffer_close(struct framebuffer_device_t* device) {
370    return device->common.close(&device->common);
371}
372
373
374__END_DECLS
375
376#endif  // ANDROID_ALLOC_INTERFACE_H
377