fb.h
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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_FB_INTERFACE_H
19 #define ANDROID_FB_INTERFACE_H
20 
21 #include <stdint.h>
22 #include <sys/cdefs.h>
23 #include <sys/types.h>
24 
25 #include <cutils/native_handle.h>
26 
27 #include <hardware/hardware.h>
28 
29 __BEGIN_DECLS
30 
31 #define GRALLOC_HARDWARE_FB0 "fb0"
32 
33 /*****************************************************************************/
34 
35 
36 /*****************************************************************************/
37 
38 typedef struct framebuffer_device_t {
39  /**
40  * Common methods of the framebuffer device. This *must* be the first member of
41  * framebuffer_device_t as users of this structure will cast a hw_device_t to
42  * framebuffer_device_t pointer in contexts where it's known the hw_device_t references a
43  * framebuffer_device_t.
44  */
46 
47  /* flags describing some attributes of the framebuffer */
48  const uint32_t flags;
49 
50  /* dimensions of the framebuffer in pixels */
51  const uint32_t width;
52  const uint32_t height;
53 
54  /* frambuffer stride in pixels */
55  const int stride;
56 
57  /* framebuffer pixel format */
58  const int format;
59 
60  /* resolution of the framebuffer's display panel in pixel per inch*/
61  const float xdpi;
62  const float ydpi;
63 
64  /* framebuffer's display panel refresh rate in frames per second */
65  const float fps;
66 
67  /* min swap interval supported by this framebuffer */
68  const int minSwapInterval;
69 
70  /* max swap interval supported by this framebuffer */
71  const int maxSwapInterval;
72 
73  /* Number of framebuffers supported*/
74  const int numFramebuffers;
75 
76  int reserved[7];
77 
78  /*
79  * requests a specific swap-interval (same definition than EGL)
80  *
81  * Returns 0 on success or -errno on error.
82  */
83  int (*setSwapInterval)(struct framebuffer_device_t* window,
84  int interval);
85 
86  /*
87  * This hook is OPTIONAL.
88  *
89  * It is non NULL If the framebuffer driver supports "update-on-demand"
90  * and the given rectangle is the area of the screen that gets
91  * updated during (*post)().
92  *
93  * This is useful on devices that are able to DMA only a portion of
94  * the screen to the display panel, upon demand -- as opposed to
95  * constantly refreshing the panel 60 times per second, for instance.
96  *
97  * Only the area defined by this rectangle is guaranteed to be valid, that
98  * is, the driver is not allowed to post anything outside of this
99  * rectangle.
100  *
101  * The rectangle evaluated during (*post)() and specifies which area
102  * of the buffer passed in (*post)() shall to be posted.
103  *
104  * return -EINVAL if width or height <=0, or if left or top < 0
105  */
106  int (*setUpdateRect)(struct framebuffer_device_t* window,
107  int left, int top, int width, int height);
108 
109  /*
110  * Post <buffer> to the display (display it on the screen)
111  * The buffer must have been allocated with the
112  * GRALLOC_USAGE_HW_FB usage flag.
113  * buffer must be the same width and height as the display and must NOT
114  * be locked.
115  *
116  * The buffer is shown during the next VSYNC.
117  *
118  * If the same buffer is posted again (possibly after some other buffer),
119  * post() will block until the the first post is completed.
120  *
121  * Internally, post() is expected to lock the buffer so that a
122  * subsequent call to gralloc_module_t::(*lock)() with USAGE_RENDER or
123  * USAGE_*_WRITE will block until it is safe; that is typically once this
124  * buffer is shown and another buffer has been posted.
125  *
126  * Returns 0 on success or -errno on error.
127  */
128  int (*post)(struct framebuffer_device_t* dev, buffer_handle_t buffer);
129 
130 
131  /*
132  * The (*compositionComplete)() method must be called after the
133  * compositor has finished issuing GL commands for client buffers.
134  */
135 
137 
138  /*
139  * This hook is OPTIONAL.
140  *
141  * If non NULL it will be caused by SurfaceFlinger on dumpsys
142  */
143  void (*dump)(struct framebuffer_device_t* dev, char *buff, int buff_len);
144 
145  /*
146  * (*enableScreen)() is used to either blank (enable=0) or
147  * unblank (enable=1) the screen this framebuffer is attached to.
148  *
149  * Returns 0 on success or -errno on error.
150  */
151  int (*enableScreen)(struct framebuffer_device_t* dev, int enable);
152 
153  void* reserved_proc[6];
154 
156 
157 
158 /** convenience API for opening and closing a supported device */
159 
160 static inline int framebuffer_open(const struct hw_module_t* module,
161  struct framebuffer_device_t** device) {
162  return module->methods->open(module,
163  GRALLOC_HARDWARE_FB0, (struct hw_device_t**)device);
164 }
165 
166 static inline int framebuffer_close(struct framebuffer_device_t* device) {
167  return device->common.close(&device->common);
168 }
169 
170 
171 __END_DECLS
172 
173 #endif // ANDROID_FB_INTERFACE_H
const float xdpi
Definition: fb.h:61
int(* open)(const struct hw_module_t *module, const char *id, struct hw_device_t **device)
Definition: hardware.h:158
int reserved[7]
Definition: fb.h:76
const uint32_t width
Definition: fb.h:51
const int minSwapInterval
Definition: fb.h:68
int(* close)(struct hw_device_t *device)
Definition: hardware.h:200
const float ydpi
Definition: fb.h:62
#define GRALLOC_HARDWARE_FB0
Definition: fb.h:31
int(* enableScreen)(struct framebuffer_device_t *dev, int enable)
Definition: fb.h:151
int(* setUpdateRect)(struct framebuffer_device_t *window, int left, int top, int width, int height)
Definition: fb.h:106
struct hw_device_t common
Definition: fb.h:45
const int stride
Definition: fb.h:55
const int numFramebuffers
Definition: fb.h:74
int(* setSwapInterval)(struct framebuffer_device_t *window, int interval)
Definition: fb.h:83
const int format
Definition: fb.h:58
const uint32_t height
Definition: fb.h:52
struct hw_module_methods_t * methods
Definition: hardware.h:142
int(* compositionComplete)(struct framebuffer_device_t *dev)
Definition: fb.h:136
void(* dump)(struct framebuffer_device_t *dev, char *buff, int buff_len)
Definition: fb.h:143
const uint32_t flags
Definition: fb.h:48
struct framebuffer_device_t framebuffer_device_t
int(* post)(struct framebuffer_device_t *dev, buffer_handle_t buffer)
Definition: fb.h:128
const float fps
Definition: fb.h:65
const int maxSwapInterval
Definition: fb.h:71
void * reserved_proc[6]
Definition: fb.h:153