2 * Copyright (C) 2008 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
18 #ifndef ANDROID_GRALLOC_INTERFACE_H
19 #define ANDROID_GRALLOC_INTERFACE_H
21 #include <system/window.h>
22 #include <hardware/hardware.h>
25 #include <sys/cdefs.h>
26 #include <sys/types.h>
28 #include <cutils/native_handle.h>
30 #include <hardware/hardware.h>
31 #include <hardware/fb.h>
35 #define GRALLOC_API_VERSION 1
38 * The id of this module
40 #define GRALLOC_HARDWARE_MODULE_ID "gralloc"
43 * Name of the graphics device to open
46 #define GRALLOC_HARDWARE_GPU0 "gpu0"
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,
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,
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,
82 /* buffer should be displayed full-screen on an external display when
85 GRALLOC_USAGE_EXTERNAL_DISP = 0x00002000,
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.
93 GRALLOC_USAGE_PROTECTED = 0x00004000,
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,
103 /*****************************************************************************/
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.
110 typedef struct gralloc_module_t {
111 struct hw_module_t common;
114 * (*registerBuffer)() must be called before a buffer_handle_t that has not
115 * been created with (*alloc_device_t::alloc)() can be used.
117 * This is intended to be used with buffer_handle_t's that have been
118 * received in this process through IPC.
120 * This function checks that the handle is indeed a valid one and prepares
121 * it for use with (*lock)() and (*unlock)().
123 * It is not necessary to call (*registerBuffer)() on a handle created
124 * with (*alloc_device_t::alloc)().
126 * returns an error if this buffer_handle_t is not valid.
128 int (*registerBuffer)(struct gralloc_module_t const* module,
129 buffer_handle_t handle);
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)().
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().
140 * It is an error to call (*unregisterBuffer)() on a buffer that wasn't
141 * explicitly registered first.
143 int (*unregisterBuffer)(struct gralloc_module_t const* module,
144 buffer_handle_t handle);
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.
151 * The caller promises to modify only pixels in the area specified
154 * The content of the buffer outside of the specified area is NOT modified
157 * If usage specifies GRALLOC_USAGE_SW_*, vaddr is filled with the address
158 * of the buffer in virtual memory.
160 * THREADING CONSIDERATIONS:
162 * It is legal for several different threads to lock a buffer from
163 * read access, none of the threads are blocked.
165 * However, locking a buffer simultaneously for write or read/write is
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.
172 * If the buffer was created with a usage mask incompatible with the
173 * requested usage flags here, -EINVAL is returned.
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,
184 * The (*unlock)() method must be called after all changes to the buffer
188 int (*unlock)(struct gralloc_module_t const* module,
189 buffer_handle_t handle);
192 /* reserved for future use */
193 int (*perform)(struct gralloc_module_t const* module,
194 int operation, ... );
196 /* reserved for future use */
197 void* reserved_proc[7];
200 /*****************************************************************************/
203 * Every device data structure must begin with hw_device_t
204 * followed by module specific public methods and attributes.
207 typedef struct alloc_device_t {
208 struct hw_device_t common;
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.
217 * Returns 0 on success or -errno on error.
220 int (*alloc)(struct alloc_device_t* dev,
221 int w, int h, int format, int usage,
222 buffer_handle_t* handle, int* stride);
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.
232 * Returns 0 on success or -errno on error.
234 int (*free)(struct alloc_device_t* dev,
235 buffer_handle_t handle);
237 /* This hook is OPTIONAL.
239 * If non NULL it will be caused by SurfaceFlinger on dumpsys
241 void (*dump)(struct alloc_device_t *dev, char *buff, int buff_len);
243 void* reserved_proc[7];
247 /** convenience API for opening and closing a supported device */
249 static 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);
255 static inline int gralloc_close(struct alloc_device_t* device) {
256 return device->common.close(&device->common);
261 #endif // ANDROID_GRALLOC_INTERFACE_H