gralloc.h revision 29ead941b377cb87bcc7fe48208b96d84d649d43 
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#include <cutils/native_handle.h>
29
30#include <hardware/hardware.h>
31#include <hardware/fb.h>
32
33__BEGIN_DECLS
34
35#define GRALLOC_API_VERSION 1
36
37/**
38 * The id of this module
39 */
40#define GRALLOC_HARDWARE_MODULE_ID "gralloc"
41
42/**
43 * Name of the graphics device to open
44 */
45
46#define GRALLOC_HARDWARE_GPU0 "gpu0"
47
48enum {
49    /* buffer is never read in software */
50    GRALLOC_USAGE_SW_READ_NEVER         = 0x00000000,
51    /* buffer is rarely read in software */
52    GRALLOC_USAGE_SW_READ_RARELY        = 0x00000002,
53    /* buffer is often read in software */
54    GRALLOC_USAGE_SW_READ_OFTEN         = 0x00000003,
55    /* mask for the software read values */
56    GRALLOC_USAGE_SW_READ_MASK          = 0x0000000F,
57
58    /* buffer is never written in software */
59    GRALLOC_USAGE_SW_WRITE_NEVER        = 0x00000000,
60    /* buffer is never written in software */
61    GRALLOC_USAGE_SW_WRITE_RARELY       = 0x00000020,
62    /* buffer is never written in software */
63    GRALLOC_USAGE_SW_WRITE_OFTEN        = 0x00000030,
64    /* mask for the software write values */
65    GRALLOC_USAGE_SW_WRITE_MASK         = 0x000000F0,
66
67    /* buffer will be used as an OpenGL ES texture */
68    GRALLOC_USAGE_HW_TEXTURE            = 0x00000100,
69    /* buffer will be used as an OpenGL ES render target */
70    GRALLOC_USAGE_HW_RENDER             = 0x00000200,
71    /* buffer will be used by the 2D hardware blitter */
72    GRALLOC_USAGE_HW_2D                 = 0x00000400,
73    /* buffer will be used by the HWComposer HAL module */
74    GRALLOC_USAGE_HW_COMPOSER           = 0x00000800,
75    /* buffer will be used with the framebuffer device */
76    GRALLOC_USAGE_HW_FB                 = 0x00001000,
77    /* buffer will be used with the HW video encoder */
78    GRALLOC_USAGE_HW_VIDEO_ENCODER      = 0x00010000,
79    /* mask for the software usage bit-mask */
80    GRALLOC_USAGE_HW_MASK               = 0x00011F00,
81
82    /* buffer should be displayed full-screen on an external display when
83     * possible
84     */
85    GRALLOC_USAGE_EXTERNAL_DISP         = 0x00002000,
86
87    /* Must have a hardware-protected path to external display sink for
88     * this buffer.  If a hardware-protected path is not available, then
89     * either don't composite only this buffer (preferred) to the
90     * external sink, or (less desirable) do not route the entire
91     * composition to the external sink.
92     */
93    GRALLOC_USAGE_PROTECTED             = 0x00004000,
94
95    /* implementation-specific private usage flags */
96    GRALLOC_USAGE_PRIVATE_0             = 0x10000000,
97    GRALLOC_USAGE_PRIVATE_1             = 0x20000000,
98    GRALLOC_USAGE_PRIVATE_2             = 0x40000000,
99    GRALLOC_USAGE_PRIVATE_3             = 0x80000000,
100    GRALLOC_USAGE_PRIVATE_MASK          = 0xF0000000,
101};
102
103/*****************************************************************************/
104
105/**
106 * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM
107 * and the fields of this data structure must begin with hw_module_t
108 * followed by module specific information.
109 */
110typedef struct gralloc_module_t {
111    struct hw_module_t common;
112
113    /*
114     * (*registerBuffer)() must be called before a buffer_handle_t that has not
115     * been created with (*alloc_device_t::alloc)() can be used.
116     *
117     * This is intended to be used with buffer_handle_t's that have been
118     * received in this process through IPC.
119     *
120     * This function checks that the handle is indeed a valid one and prepares
121     * it for use with (*lock)() and (*unlock)().
122     *
123     * It is not necessary to call (*registerBuffer)() on a handle created
124     * with (*alloc_device_t::alloc)().
125     *
126     * returns an error if this buffer_handle_t is not valid.
127     */
128    int (*registerBuffer)(struct gralloc_module_t const* module,
129            buffer_handle_t handle);
130
131    /*
132     * (*unregisterBuffer)() is called once this handle is no longer needed in
133     * this process. After this call, it is an error to call (*lock)(),
134     * (*unlock)(), or (*registerBuffer)().
135     *
136     * This function doesn't close or free the handle itself; this is done
137     * by other means, usually through libcutils's native_handle_close() and
138     * native_handle_free().
139     *
140     * It is an error to call (*unregisterBuffer)() on a buffer that wasn't
141     * explicitly registered first.
142     */
143    int (*unregisterBuffer)(struct gralloc_module_t const* module,
144            buffer_handle_t handle);
145
146    /*
147     * The (*lock)() method is called before a buffer is accessed for the
148     * specified usage. This call may block, for instance if the h/w needs
149     * to finish rendering or if CPU caches need to be synchronized.
150     *
151     * The caller promises to modify only pixels in the area specified
152     * by (l,t,w,h).
153     *
154     * The content of the buffer outside of the specified area is NOT modified
155     * by this call.
156     *
157     * If usage specifies GRALLOC_USAGE_SW_*, vaddr is filled with the address
158     * of the buffer in virtual memory.
159     *
160     * THREADING CONSIDERATIONS:
161     *
162     * It is legal for several different threads to lock a buffer from
163     * read access, none of the threads are blocked.
164     *
165     * However, locking a buffer simultaneously for write or read/write is
166     * undefined, but:
167     * - shall not result in termination of the process
168     * - shall not block the caller
169     * It is acceptable to return an error or to leave the buffer's content
170     * into an indeterminate state.
171     *
172     * If the buffer was created with a usage mask incompatible with the
173     * requested usage flags here, -EINVAL is returned.
174     *
175     */
176
177    int (*lock)(struct gralloc_module_t const* module,
178            buffer_handle_t handle, int usage,
179            int l, int t, int w, int h,
180            void** vaddr);
181
182
183    /*
184     * The (*unlock)() method must be called after all changes to the buffer
185     * are completed.
186     */
187
188    int (*unlock)(struct gralloc_module_t const* module,
189            buffer_handle_t handle);
190
191
192    /* reserved for future use */
193    int (*perform)(struct gralloc_module_t const* module,
194            int operation, ... );
195
196    /* reserved for future use */
197    void* reserved_proc[7];
198} gralloc_module_t;
199
200/*****************************************************************************/
201
202/**
203 * Every device data structure must begin with hw_device_t
204 * followed by module specific public methods and attributes.
205 */
206
207typedef struct alloc_device_t {
208    struct hw_device_t common;
209
210    /*
211     * (*alloc)() Allocates a buffer in graphic memory with the requested
212     * parameters and returns a buffer_handle_t and the stride in pixels to
213     * allow the implementation to satisfy hardware constraints on the width
214     * of a pixmap (eg: it may have to be multiple of 8 pixels).
215     * The CALLER TAKES OWNERSHIP of the buffer_handle_t.
216     *
217     * Returns 0 on success or -errno on error.
218     */
219
220    int (*alloc)(struct alloc_device_t* dev,
221            int w, int h, int format, int usage,
222            buffer_handle_t* handle, int* stride);
223
224    /*
225     * (*free)() Frees a previously allocated buffer.
226     * Behavior is undefined if the buffer is still mapped in any process,
227     * but shall not result in termination of the program or security breaches
228     * (allowing a process to get access to another process' buffers).
229     * THIS FUNCTION TAKES OWNERSHIP of the buffer_handle_t which becomes
230     * invalid after the call.
231     *
232     * Returns 0 on success or -errno on error.
233     */
234    int (*free)(struct alloc_device_t* dev,
235            buffer_handle_t handle);
236
237    /* This hook is OPTIONAL.
238     *
239     * If non NULL it will be caused by SurfaceFlinger on dumpsys
240     */
241    void (*dump)(struct alloc_device_t *dev, char *buff, int buff_len);
242
243    void* reserved_proc[7];
244} alloc_device_t;
245
246
247/** convenience API for opening and closing a supported device */
248
249static inline int gralloc_open(const struct hw_module_t* module,
250        struct alloc_device_t** device) {
251    return module->methods->open(module,
252            GRALLOC_HARDWARE_GPU0, (struct hw_device_t**)device);
253}
254
255static inline int gralloc_close(struct alloc_device_t* device) {
256    return device->common.close(&device->common);
257}
258
259__END_DECLS
260
261#endif  // ANDROID_ALLOC_INTERFACE_H
262