1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
|
/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <stdbool.h>
#include <stddef.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#define LOG_TAG "libsuspend"
#include <cutils/log.h>
#include "autosuspend_ops.h"
#define EARLYSUSPEND_SYS_POWER_STATE "/sys/power/state"
#define EARLYSUSPEND_WAIT_FOR_FB_SLEEP "/sys/power/wait_for_fb_sleep"
#define EARLYSUSPEND_WAIT_FOR_FB_WAKE "/sys/power/wait_for_fb_wake"
static int sPowerStatefd;
static const char *pwr_state_mem = "mem";
static const char *pwr_state_on = "on";
static pthread_t earlysuspend_thread;
static pthread_mutex_t earlysuspend_mutex = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t earlysuspend_cond = PTHREAD_COND_INITIALIZER;
static bool wait_for_earlysuspend;
static enum {
EARLYSUSPEND_ON,
EARLYSUSPEND_MEM,
} earlysuspend_state = EARLYSUSPEND_ON;
int wait_for_fb_wake(void)
{
int err = 0;
char buf;
int fd = TEMP_FAILURE_RETRY(open(EARLYSUSPEND_WAIT_FOR_FB_WAKE, O_RDONLY, 0));
// if the file doesn't exist, the error will be caught in read() below
err = TEMP_FAILURE_RETRY(read(fd, &buf, 1));
ALOGE_IF(err < 0,
"*** ANDROID_WAIT_FOR_FB_WAKE failed (%s)", strerror(errno));
close(fd);
return err < 0 ? err : 0;
}
static int wait_for_fb_sleep(void)
{
int err = 0;
char buf;
int fd = TEMP_FAILURE_RETRY(open(EARLYSUSPEND_WAIT_FOR_FB_SLEEP, O_RDONLY, 0));
// if the file doesn't exist, the error will be caught in read() below
err = TEMP_FAILURE_RETRY(read(fd, &buf, 1));
ALOGE_IF(err < 0,
"*** ANDROID_WAIT_FOR_FB_SLEEP failed (%s)", strerror(errno));
close(fd);
return err < 0 ? err : 0;
}
static void *earlysuspend_thread_func(void __unused *arg)
{
while (1) {
if (wait_for_fb_sleep()) {
ALOGE("Failed reading wait_for_fb_sleep, exiting earlysuspend thread\n");
return NULL;
}
pthread_mutex_lock(&earlysuspend_mutex);
earlysuspend_state = EARLYSUSPEND_MEM;
pthread_cond_signal(&earlysuspend_cond);
pthread_mutex_unlock(&earlysuspend_mutex);
if (wait_for_fb_wake()) {
ALOGE("Failed reading wait_for_fb_wake, exiting earlysuspend thread\n");
return NULL;
}
pthread_mutex_lock(&earlysuspend_mutex);
earlysuspend_state = EARLYSUSPEND_ON;
pthread_cond_signal(&earlysuspend_cond);
pthread_mutex_unlock(&earlysuspend_mutex);
}
}
static int autosuspend_earlysuspend_enable(void)
{
char buf[80];
int ret;
ALOGV("autosuspend_earlysuspend_enable\n");
ret = write(sPowerStatefd, pwr_state_mem, strlen(pwr_state_mem));
if (ret < 0) {
strerror_r(errno, buf, sizeof(buf));
ALOGE("Error writing to %s: %s\n", EARLYSUSPEND_SYS_POWER_STATE, buf);
goto err;
}
if (wait_for_earlysuspend) {
pthread_mutex_lock(&earlysuspend_mutex);
while (earlysuspend_state != EARLYSUSPEND_MEM) {
pthread_cond_wait(&earlysuspend_cond, &earlysuspend_mutex);
}
pthread_mutex_unlock(&earlysuspend_mutex);
}
ALOGV("autosuspend_earlysuspend_enable done\n");
return 0;
err:
return ret;
}
static int autosuspend_earlysuspend_disable(void)
{
char buf[80];
int ret;
ALOGV("autosuspend_earlysuspend_disable\n");
ret = TEMP_FAILURE_RETRY(write(sPowerStatefd, pwr_state_on, strlen(pwr_state_on)));
if (ret < 0) {
strerror_r(errno, buf, sizeof(buf));
ALOGE("Error writing to %s: %s\n", EARLYSUSPEND_SYS_POWER_STATE, buf);
goto err;
}
if (wait_for_earlysuspend) {
pthread_mutex_lock(&earlysuspend_mutex);
while (earlysuspend_state != EARLYSUSPEND_ON) {
pthread_cond_wait(&earlysuspend_cond, &earlysuspend_mutex);
}
pthread_mutex_unlock(&earlysuspend_mutex);
}
ALOGV("autosuspend_earlysuspend_disable done\n");
return 0;
err:
return ret;
}
struct autosuspend_ops autosuspend_earlysuspend_ops = {
.enable = autosuspend_earlysuspend_enable,
.disable = autosuspend_earlysuspend_disable,
};
void start_earlysuspend_thread(void)
{
char buf[80];
int ret;
ret = access(EARLYSUSPEND_WAIT_FOR_FB_SLEEP, F_OK);
if (ret < 0) {
return;
}
ret = access(EARLYSUSPEND_WAIT_FOR_FB_WAKE, F_OK);
if (ret < 0) {
return;
}
wait_for_fb_wake();
ALOGI("Starting early suspend unblocker thread\n");
ret = pthread_create(&earlysuspend_thread, NULL, earlysuspend_thread_func, NULL);
if (ret) {
strerror_r(errno, buf, sizeof(buf));
ALOGE("Error creating thread: %s\n", buf);
return;
}
wait_for_earlysuspend = true;
}
struct autosuspend_ops *autosuspend_earlysuspend_init(void)
{
char buf[80];
int ret;
sPowerStatefd = TEMP_FAILURE_RETRY(open(EARLYSUSPEND_SYS_POWER_STATE, O_RDWR));
if (sPowerStatefd < 0) {
strerror_r(errno, buf, sizeof(buf));
ALOGW("Error opening %s: %s\n", EARLYSUSPEND_SYS_POWER_STATE, buf);
return NULL;
}
ret = TEMP_FAILURE_RETRY(write(sPowerStatefd, "on", 2));
if (ret < 0) {
strerror_r(errno, buf, sizeof(buf));
ALOGW("Error writing 'on' to %s: %s\n", EARLYSUSPEND_SYS_POWER_STATE, buf);
goto err_write;
}
ALOGI("Selected early suspend\n");
start_earlysuspend_thread();
return &autosuspend_earlysuspend_ops;
err_write:
close(sPowerStatefd);
return NULL;
}
|
