hardware/gralloc.h

   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
  48 enum {
  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     /* buffer will be written by the HW camera pipeline */
  80     GRALLOC_USAGE_HW_CAMERA_WRITE       = 0x00020000,
  81     /* buffer will be read by the HW camera pipeline */
  82     GRALLOC_USAGE_HW_CAMERA_READ        = 0x00040000,
  83     /* buffer will be used as part of zero-shutter-lag queue */
  84     GRALLOC_USAGE_HW_CAMERA_ZSL         = 0x00060000,
  85     /* mask for the camera access values */
  86     GRALLOC_USAGE_HW_CAMERA_MASK        = 0x00060000,
  87     /* mask for the software usage bit-mask */
  88     GRALLOC_USAGE_HW_MASK               = 0x00071F00,
  89
  90     /* buffer should be displayed full-screen on an external display when
  91      * possible
  92      */
  93     GRALLOC_USAGE_EXTERNAL_DISP         = 0x00002000,
  94
  95     /* Must have a hardware-protected path to external display sink for
  96      * this buffer.  If a hardware-protected path is not available, then
  97      * either don't composite only this buffer (preferred) to the
  98      * external sink, or (less desirable) do not route the entire
  99      * composition to the external sink.
 100      */
 101     GRALLOC_USAGE_PROTECTED             = 0x00004000,
 102
 103     /* implementation-specific private usage flags */
 104     GRALLOC_USAGE_PRIVATE_0             = 0x10000000,
 105     GRALLOC_USAGE_PRIVATE_1             = 0x20000000,
 106     GRALLOC_USAGE_PRIVATE_2             = 0x40000000,
 107     GRALLOC_USAGE_PRIVATE_3             = 0x80000000,
 108     GRALLOC_USAGE_PRIVATE_MASK          = 0xF0000000,
 109 };
 110
 111 /*****************************************************************************/
 112
 113 /**
 114  * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM
 115  * and the fields of this data structure must begin with hw_module_t
 116  * followed by module specific information.
 117  */
 118 typedef struct gralloc_module_t {
 119     struct hw_module_t common;
 120
 121     /*
 122      * (*registerBuffer)() must be called before a buffer_handle_t that has not
 123      * been created with (*alloc_device_t::alloc)() can be used.
 124      *
 125      * This is intended to be used with buffer_handle_t's that have been
 126      * received in this process through IPC.
 127      *
 128      * This function checks that the handle is indeed a valid one and prepares
 129      * it for use with (*lock)() and (*unlock)().
 130      *
 131      * It is not necessary to call (*registerBuffer)() on a handle created
 132      * with (*alloc_device_t::alloc)().
 133      *
 134      * returns an error if this buffer_handle_t is not valid.
 135      */
 136     int (*registerBuffer)(struct gralloc_module_t const* module,
 137             buffer_handle_t handle);
 138
 139     /*
 140      * (*unregisterBuffer)() is called once this handle is no longer needed in
 141      * this process. After this call, it is an error to call (*lock)(),
 142      * (*unlock)(), or (*registerBuffer)().
 143      *
 144      * This function doesn't close or free the handle itself; this is done
 145      * by other means, usually through libcutils's native_handle_close() and
 146      * native_handle_free().
 147      *
 148      * It is an error to call (*unregisterBuffer)() on a buffer that wasn't
 149      * explicitly registered first.
 150      */
 151     int (*unregisterBuffer)(struct gralloc_module_t const* module,
 152             buffer_handle_t handle);
 153
 154     /*
 155      * The (*lock)() method is called before a buffer is accessed for the
 156      * specified usage. This call may block, for instance if the h/w needs
 157      * to finish rendering or if CPU caches need to be synchronized.
 158      *
 159      * The caller promises to modify only pixels in the area specified
 160      * by (l,t,w,h).
 161      *
 162      * The content of the buffer outside of the specified area is NOT modified
 163      * by this call.
 164      *
 165      * If usage specifies GRALLOC_USAGE_SW_*, vaddr is filled with the address
 166      * of the buffer in virtual memory.
 167      *
 168      * THREADING CONSIDERATIONS:
 169      *
 170      * It is legal for several different threads to lock a buffer from
 171      * read access, none of the threads are blocked.
 172      *
 173      * However, locking a buffer simultaneously for write or read/write is
 174      * undefined, but:
 175      * - shall not result in termination of the process
 176      * - shall not block the caller
 177      * It is acceptable to return an error or to leave the buffer's content
 178      * into an indeterminate state.
 179      *
 180      * If the buffer was created with a usage mask incompatible with the
 181      * requested usage flags here, -EINVAL is returned.
 182      *
 183      */
 184
 185     int (*lock)(struct gralloc_module_t const* module,
 186             buffer_handle_t handle, int usage,
 187             int l, int t, int w, int h,
 188             void** vaddr);
 189
 190
 191     /*
 192      * The (*unlock)() method must be called after all changes to the buffer
 193      * are completed.
 194      */
 195
 196     int (*unlock)(struct gralloc_module_t const* module,
 197             buffer_handle_t handle);
 198
 199
 200     /* reserved for future use */
 201     int (*perform)(struct gralloc_module_t const* module,
 202             int operation, ... );
 203
 204     /* reserved for future use */
 205     void* reserved_proc[7];
 206 } gralloc_module_t;
 207
 208 /*****************************************************************************/
 209
 210 /**
 211  * Every device data structure must begin with hw_device_t
 212  * followed by module specific public methods and attributes.
 213  */
 214
 215 typedef struct alloc_device_t {
 216     struct hw_device_t common;
 217
 218     /*
 219      * (*alloc)() Allocates a buffer in graphic memory with the requested
 220      * parameters and returns a buffer_handle_t and the stride in pixels to
 221      * allow the implementation to satisfy hardware constraints on the width
 222      * of a pixmap (eg: it may have to be multiple of 8 pixels).
 223      * The CALLER TAKES OWNERSHIP of the buffer_handle_t.
 224      *
 225      * Returns 0 on success or -errno on error.
 226      */
 227
 228     int (*alloc)(struct alloc_device_t* dev,
 229             int w, int h, int format, int usage,
 230             buffer_handle_t* handle, int* stride);
 231
 232     /*
 233      * (*free)() Frees a previously allocated buffer.
 234      * Behavior is undefined if the buffer is still mapped in any process,
 235      * but shall not result in termination of the program or security breaches
 236      * (allowing a process to get access to another process' buffers).
 237      * THIS FUNCTION TAKES OWNERSHIP of the buffer_handle_t which becomes
 238      * invalid after the call.
 239      *
 240      * Returns 0 on success or -errno on error.
 241      */
 242     int (*free)(struct alloc_device_t* dev,
 243             buffer_handle_t handle);
 244
 245     /* This hook is OPTIONAL.
 246      *
 247      * If non NULL it will be caused by SurfaceFlinger on dumpsys
 248      */
 249     void (*dump)(struct alloc_device_t *dev, char *buff, int buff_len);
 250
 251     void* reserved_proc[7];
 252 } alloc_device_t;
 253
 254
 255 /** convenience API for opening and closing a supported device */
 256
 257 static inline int gralloc_open(const struct hw_module_t* module,
 258         struct alloc_device_t** device) {
 259     return module->methods->open(module,
 260             GRALLOC_HARDWARE_GPU0, (struct hw_device_t**)device);
 261 }
 262
 263 static inline int gralloc_close(struct alloc_device_t* device) {
 264     return device->common.close(&device->common);
 265 }
 266
 267 __END_DECLS
 268
 269 #endif  // ANDROID_GRALLOC_INTERFACE_H