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
38typedef 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     */
45    struct hw_device_t common;
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
136    int (*compositionComplete)(struct framebuffer_device_t* dev);
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
155} framebuffer_device_t;
156
157
158/** convenience API for opening and closing a supported device */
159
160static 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, TO_HW_DEVICE_T_OPEN(device));
164}
165
166static 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
174