1 /*
2 * Copyright (C) 2010 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 #ifndef ANDROID_INCLUDE_HARDWARE_HWCOMPOSER_H
18 #define ANDROID_INCLUDE_HARDWARE_HWCOMPOSER_H
19
20 #include <stdint.h>
21 #include <sys/cdefs.h>
22
23 #include <hardware/gralloc.h>
24 #include <hardware/hardware.h>
25 #include <cutils/native_handle.h>
26
27 __BEGIN_DECLS
28
29 /*****************************************************************************/
30
31 #define HWC_API_VERSION 1
32
33 /**
34 * The id of this module
35 */
36 #define HWC_HARDWARE_MODULE_ID "hwcomposer"
37
38 /**
39 * Name of the sensors device to open
40 */
41 #define HWC_HARDWARE_COMPOSER "composer"
42
43
44 enum {
45 /* hwc_composer_device_t::set failed in EGL */
46 HWC_EGL_ERROR = -1
47 };
48
49 /*
50 * hwc_layer_t::hints values
51 * Hints are set by the HAL and read by SurfaceFlinger
52 */
53 enum {
54 /*
55 * HWC can set the HWC_HINT_TRIPLE_BUFFER hint to indicate to SurfaceFlinger
56 * that it should triple buffer this layer. Typically HWC does this when
57 * the layer will be unavailable for use for an extended period of time,
58 * e.g. if the display will be fetching data directly from the layer and
59 * the layer can not be modified until after the next set().
60 */
61 HWC_HINT_TRIPLE_BUFFER = 0x00000001,
62
63 /*
64 * HWC sets HWC_HINT_CLEAR_FB to tell SurfaceFlinger that it should clear the
65 * framebuffer with transparent pixels where this layer would be.
66 * SurfaceFlinger will only honor this flag when the layer has no blending
67 *
68 */
69 HWC_HINT_CLEAR_FB = 0x00000002
70 };
71
72 /*
73 * hwc_layer_t::flags values
74 * Flags are set by SurfaceFlinger and read by the HAL
75 */
76 enum {
77 /*
78 * HWC_SKIP_LAYER is set by SurfaceFlnger to indicate that the HAL
79 * shall not consider this layer for composition as it will be handled
80 * by SurfaceFlinger (just as if compositionType was set to HWC_OVERLAY).
81 */
82 HWC_SKIP_LAYER = 0x00000001,
83 };
84
85 /*
86 * hwc_layer_t::compositionType values
87 */
88 enum {
89 /* this layer is to be drawn into the framebuffer by SurfaceFlinger */
90 HWC_FRAMEBUFFER = 0,
91
92 /* this layer will be handled in the HWC */
93 HWC_OVERLAY = 1,
94 };
95
96 /*
97 * hwc_layer_t::blending values
98 */
99 enum {
100 /* no blending */
101 HWC_BLENDING_NONE = 0x0100,
102
103 /* ONE / ONE_MINUS_SRC_ALPHA */
104 HWC_BLENDING_PREMULT = 0x0105,
105
106 /* SRC_ALPHA / ONE_MINUS_SRC_ALPHA */
107 HWC_BLENDING_COVERAGE = 0x0405
108 };
109
110 /*
111 * hwc_layer_t::transform values
112 */
113 enum {
114 /* flip source image horizontally */
115 HWC_TRANSFORM_FLIP_H = HAL_TRANSFORM_FLIP_H,
116 /* flip source image vertically */
117 HWC_TRANSFORM_FLIP_V = HAL_TRANSFORM_FLIP_V,
118 /* rotate source image 90 degrees clock-wise */
119 HWC_TRANSFORM_ROT_90 = HAL_TRANSFORM_ROT_90,
120 /* rotate source image 180 degrees */
121 HWC_TRANSFORM_ROT_180 = HAL_TRANSFORM_ROT_180,
122 /* rotate source image 270 degrees clock-wise */
123 HWC_TRANSFORM_ROT_270 = HAL_TRANSFORM_ROT_270,
124 };
125
126 typedef struct hwc_rect {
127 int left;
128 int top;
129 int right;
130 int bottom;
131 } hwc_rect_t;
132
133 typedef struct hwc_region {
134 size_t numRects;
135 hwc_rect_t const* rects;
136 } hwc_region_t;
137
138 typedef struct hwc_layer {
139 /*
140 * initially set to HWC_FRAMEBUFFER, indicates the layer will
141 * be drawn into the framebuffer using OpenGL ES.
142 * The HWC can toggle this value to HWC_OVERLAY, to indicate
143 * it will handle the layer.
144 */
145 int32_t compositionType;
146
147 /* see hwc_layer_t::hints above */
148 uint32_t hints;
149
150 /* see hwc_layer_t::flags above */
151 uint32_t flags;
152
153 /* handle of buffer to compose. this handle is guaranteed to have been
154 * allocated with gralloc */
155 buffer_handle_t handle;
156
157 /* transformation to apply to the buffer during composition */
158 uint32_t transform;
159
160 /* blending to apply during composition */
161 int32_t blending;
162
163 /* area of the source to consider, the origin is the top-left corner of
164 * the buffer */
165 hwc_rect_t sourceCrop;
166
167 /* where to composite the sourceCrop onto the display. The sourceCrop
168 * is scaled using linear filtering to the displayFrame. The origin is the
169 * top-left corner of the screen.
170 */
171 hwc_rect_t displayFrame;
172
173 /* visible region in screen space. The origin is the
174 * top-left corner of the screen.
175 * The visible region INCLUDES areas overlapped by a translucent layer.
176 */
177 hwc_region_t visibleRegionScreen;
178 } hwc_layer_t;
179
180
181 /*
182 * hwc_layer_list_t::flags values
183 */
184 enum {
185 /*
186 * HWC_GEOMETRY_CHANGED is set by SurfaceFlinger to indicate that the list
187 * passed to (*prepare)() has changed by more than just the buffer handles.
188 */
189 HWC_GEOMETRY_CHANGED = 0x00000001,
190 };
191
192 /*
193 * List of layers.
194 * The handle members of hwLayers elements must be unique.
195 */
196 typedef struct hwc_layer_list {
197 uint32_t flags;
198 size_t numHwLayers;
199 hwc_layer_t hwLayers[0];
200 } hwc_layer_list_t;
201
202 /* This represents a display, typically an EGLDisplay object */
203 typedef void* hwc_display_t;
204
205 /* This represents a surface, typically an EGLSurface object */
206 typedef void* hwc_surface_t;
207
208
209 /* see hwc_composer_device::registerProcs()
210 * Any of the callbacks can be NULL, in which case the corresponding
211 * functionality is not supported.
212 */
213 typedef struct hwc_procs {
214 /*
215 * (*invalidate)() triggers a screen refresh, in particular prepare and set
216 * will be called shortly after this call is made. Note that there is
217 * NO GUARANTEE that the screen refresh will happen after invalidate()
218 * returns (in particular, it could happen before).
219 * invalidate() is GUARANTEED TO NOT CALL BACK into the h/w composer HAL and
220 * it is safe to call invalidate() from any of hwc_composer_device
221 * hooks, unless noted otherwise.
222 */
223 void (*invalidate)(struct hwc_procs* procs);
224 } hwc_procs_t;
225
226
227 /*****************************************************************************/
228
229 typedef struct hwc_module {
230 struct hw_module_t common;
231 } hwc_module_t;
232
233
234 typedef struct hwc_composer_device {
235 struct hw_device_t common;
236
237 /*
238 * (*prepare)() is called for each frame before composition and is used by
239 * SurfaceFlinger to determine what composition steps the HWC can handle.
240 *
241 * (*prepare)() can be called more than once, the last call prevails.
242 *
243 * The HWC responds by setting the compositionType field to either
244 * HWC_FRAMEBUFFER or HWC_OVERLAY. In the former case, the composition for
245 * this layer is handled by SurfaceFlinger with OpenGL ES, in the later
246 * case, the HWC will have to handle this layer's composition.
247 *
248 * (*prepare)() is called with HWC_GEOMETRY_CHANGED to indicate that the
249 * list's geometry has changed, that is, when more than just the buffer's
250 * handles have been updated. Typically this happens (but is not limited to)
251 * when a window is added, removed, resized or moved.
252 *
253 * a NULL list parameter or a numHwLayers of zero indicates that the
254 * entire composition will be handled by SurfaceFlinger with OpenGL ES.
255 *
256 * returns: 0 on success. An negative error code on error. If an error is
257 * returned, SurfaceFlinger will assume that none of the layer will be
258 * handled by the HWC.
259 */
260 int (*prepare)(struct hwc_composer_device *dev, hwc_layer_list_t* list);
261
262
263 /*
264 * (*set)() is used in place of eglSwapBuffers(), and assumes the same
265 * functionality, except it also commits the work list atomically with
266 * the actual eglSwapBuffers().
267 *
268 * The list parameter is guaranteed to be the same as the one returned
269 * from the last call to (*prepare)().
270 *
271 * When this call returns the caller assumes that:
272 *
273 * - the display will be updated in the near future with the content
274 * of the work list, without artifacts during the transition from the
275 * previous frame.
276 *
277 * - all objects are available for immediate access or destruction, in
278 * particular, hwc_region_t::rects data and hwc_layer_t::layer's buffer.
279 * Note that this means that immediately accessing (potentially from a
280 * different process) a buffer used in this call will not result in
281 * screen corruption, the driver must apply proper synchronization or
282 * scheduling (eg: block the caller, such as gralloc_module_t::lock(),
283 * OpenGL ES, Camera, Codecs, etc..., or schedule the caller's work
284 * after the buffer is freed from the actual composition).
285 *
286 * a NULL list parameter or a numHwLayers of zero indicates that the
287 * entire composition has been handled by SurfaceFlinger with OpenGL ES.
288 * In this case, (*set)() behaves just like eglSwapBuffers().
289 *
290 * returns: 0 on success. An negative error code on error:
291 * HWC_EGL_ERROR: eglGetError() will provide the proper error code
292 * Another code for non EGL errors.
293 *
294 */
295 int (*set)(struct hwc_composer_device *dev,
296 hwc_display_t dpy,
297 hwc_surface_t sur,
298 hwc_layer_list_t* list);
299 /*
300 * This hook is OPTIONAL.
301 *
302 * If non NULL it will be called by SurfaceFlinger on dumpsys
303 */
304 void (*dump)(struct hwc_composer_device* dev, char *buff, int buff_len);
305
306 /*
307 * This hook is OPTIONAL.
308 *
309 * (*registerProcs)() registers a set of callbacks the h/w composer HAL
310 * can later use. It is FORBIDDEN to call any of the callbacks from
311 * within registerProcs(). registerProcs() must save the hwc_procs_t pointer
312 * which is needed when calling a registered callback.
313 * Each call to registerProcs replaces the previous set of callbacks.
314 * registerProcs is called with NULL to unregister all callbacks.
315 *
316 * Any of the callbacks can be NULL, in which case the corresponding
317 * functionality is not supported.
318 */
319 void (*registerProcs)(struct hwc_composer_device* dev,
320 hwc_procs_t const* procs);
321
322 void* reserved_proc[6];
323
324 } hwc_composer_device_t;
325
326
327 /** convenience API for opening and closing a device */
328
hwc_open(const struct hw_module_t * module,hwc_composer_device_t ** device)329 static inline int hwc_open(const struct hw_module_t* module,
330 hwc_composer_device_t** device) {
331 return module->methods->open(module,
332 HWC_HARDWARE_COMPOSER, (struct hw_device_t**)device);
333 }
334
hwc_close(hwc_composer_device_t * device)335 static inline int hwc_close(hwc_composer_device_t* device) {
336 return device->common.close(&device->common);
337 }
338
339
340 /*****************************************************************************/
341
342 __END_DECLS
343
344 #endif /* ANDROID_INCLUDE_HARDWARE_HWCOMPOSER_H */
345