Colin Cross | a2582c2 | 2012-05-03 17:30:16 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2012 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 | #include <errno.h> |
| 18 | #include <fcntl.h> |
| 19 | #include <pthread.h> |
| 20 | #include <semaphore.h> |
| 21 | #include <stddef.h> |
| 22 | #include <string.h> |
| 23 | #include <sys/stat.h> |
| 24 | #include <sys/types.h> |
| 25 | #include <unistd.h> |
| 26 | |
| 27 | #define LOG_TAG "libsuspend" |
| 28 | #include <cutils/log.h> |
| 29 | |
| 30 | #include "autosuspend_ops.h" |
| 31 | |
| 32 | #define SYS_POWER_STATE "/sys/power/state" |
| 33 | #define SYS_POWER_WAKEUP_COUNT "/sys/power/wakeup_count" |
| 34 | |
| 35 | static int state_fd; |
| 36 | static int wakeup_count_fd; |
| 37 | static pthread_t suspend_thread; |
| 38 | static sem_t suspend_lockout; |
| 39 | static const char *sleep_state = "mem"; |
| 40 | |
Edwin Vane | 62f9ffa | 2012-07-26 15:26:46 -0400 | [diff] [blame] | 41 | static void *suspend_thread_func(void *arg __attribute__((unused))) |
Colin Cross | a2582c2 | 2012-05-03 17:30:16 -0700 | [diff] [blame] | 42 | { |
| 43 | char buf[80]; |
| 44 | char wakeup_count[20]; |
| 45 | int wakeup_count_len; |
| 46 | int ret; |
| 47 | |
| 48 | while (1) { |
| 49 | usleep(100000); |
| 50 | ALOGV("%s: read wakeup_count\n", __func__); |
| 51 | lseek(wakeup_count_fd, 0, SEEK_SET); |
| 52 | wakeup_count_len = read(wakeup_count_fd, wakeup_count, sizeof(wakeup_count)); |
| 53 | if (wakeup_count_len < 0) { |
| 54 | strerror_r(errno, buf, sizeof(buf)); |
| 55 | ALOGE("Error reading from %s: %s\n", SYS_POWER_WAKEUP_COUNT, buf); |
| 56 | wakeup_count_len = 0; |
| 57 | continue; |
| 58 | } |
| 59 | if (!wakeup_count_len) { |
| 60 | ALOGE("Empty wakeup count\n"); |
| 61 | continue; |
| 62 | } |
| 63 | |
| 64 | ALOGV("%s: wait\n", __func__); |
| 65 | ret = sem_wait(&suspend_lockout); |
| 66 | if (ret < 0) { |
| 67 | strerror_r(errno, buf, sizeof(buf)); |
| 68 | ALOGE("Error waiting on semaphore: %s\n", buf); |
| 69 | continue; |
| 70 | } |
| 71 | |
| 72 | ALOGV("%s: write %*s to wakeup_count\n", __func__, wakeup_count_len, wakeup_count); |
| 73 | ret = write(wakeup_count_fd, wakeup_count, wakeup_count_len); |
| 74 | if (ret < 0) { |
| 75 | strerror_r(errno, buf, sizeof(buf)); |
| 76 | ALOGE("Error writing to %s: %s\n", SYS_POWER_WAKEUP_COUNT, buf); |
| 77 | } else { |
| 78 | ALOGV("%s: write %s to %s\n", __func__, sleep_state, SYS_POWER_STATE); |
| 79 | ret = write(state_fd, sleep_state, strlen(sleep_state)); |
| 80 | if (ret < 0) { |
| 81 | strerror_r(errno, buf, sizeof(buf)); |
| 82 | ALOGE("Error writing to %s: %s\n", SYS_POWER_STATE, buf); |
| 83 | } |
| 84 | } |
| 85 | |
| 86 | ALOGV("%s: release sem\n", __func__); |
| 87 | ret = sem_post(&suspend_lockout); |
| 88 | if (ret < 0) { |
| 89 | strerror_r(errno, buf, sizeof(buf)); |
| 90 | ALOGE("Error releasing semaphore: %s\n", buf); |
| 91 | } |
| 92 | } |
| 93 | return NULL; |
| 94 | } |
| 95 | |
| 96 | static int autosuspend_wakeup_count_enable(void) |
| 97 | { |
| 98 | char buf[80]; |
| 99 | int ret; |
| 100 | |
| 101 | ALOGV("autosuspend_wakeup_count_enable\n"); |
| 102 | |
| 103 | ret = sem_post(&suspend_lockout); |
| 104 | |
| 105 | if (ret < 0) { |
| 106 | strerror_r(errno, buf, sizeof(buf)); |
| 107 | ALOGE("Error changing semaphore: %s\n", buf); |
| 108 | } |
| 109 | |
| 110 | ALOGV("autosuspend_wakeup_count_enable done\n"); |
| 111 | |
| 112 | return ret; |
| 113 | } |
| 114 | |
| 115 | static int autosuspend_wakeup_count_disable(void) |
| 116 | { |
| 117 | char buf[80]; |
| 118 | int ret; |
| 119 | |
| 120 | ALOGV("autosuspend_wakeup_count_disable\n"); |
| 121 | |
| 122 | ret = sem_wait(&suspend_lockout); |
| 123 | |
| 124 | if (ret < 0) { |
| 125 | strerror_r(errno, buf, sizeof(buf)); |
| 126 | ALOGE("Error changing semaphore: %s\n", buf); |
| 127 | } |
| 128 | |
| 129 | ALOGV("autosuspend_wakeup_count_disable done\n"); |
| 130 | |
| 131 | return ret; |
| 132 | } |
| 133 | |
| 134 | struct autosuspend_ops autosuspend_wakeup_count_ops = { |
| 135 | .enable = autosuspend_wakeup_count_enable, |
| 136 | .disable = autosuspend_wakeup_count_disable, |
| 137 | }; |
| 138 | |
| 139 | struct autosuspend_ops *autosuspend_wakeup_count_init(void) |
| 140 | { |
| 141 | int ret; |
| 142 | char buf[80]; |
| 143 | |
| 144 | state_fd = open(SYS_POWER_STATE, O_RDWR); |
| 145 | if (state_fd < 0) { |
| 146 | strerror_r(errno, buf, sizeof(buf)); |
| 147 | ALOGE("Error opening %s: %s\n", SYS_POWER_STATE, buf); |
| 148 | goto err_open_state; |
| 149 | } |
| 150 | |
| 151 | wakeup_count_fd = open(SYS_POWER_WAKEUP_COUNT, O_RDWR); |
| 152 | if (wakeup_count_fd < 0) { |
| 153 | strerror_r(errno, buf, sizeof(buf)); |
| 154 | ALOGE("Error opening %s: %s\n", SYS_POWER_WAKEUP_COUNT, buf); |
| 155 | goto err_open_wakeup_count; |
| 156 | } |
| 157 | |
| 158 | ret = sem_init(&suspend_lockout, 0, 0); |
| 159 | if (ret < 0) { |
| 160 | strerror_r(errno, buf, sizeof(buf)); |
| 161 | ALOGE("Error creating semaphore: %s\n", buf); |
| 162 | goto err_sem_init; |
| 163 | } |
| 164 | ret = pthread_create(&suspend_thread, NULL, suspend_thread_func, NULL); |
| 165 | if (ret) { |
| 166 | strerror_r(ret, buf, sizeof(buf)); |
| 167 | ALOGE("Error creating thread: %s\n", buf); |
| 168 | goto err_pthread_create; |
| 169 | } |
| 170 | |
| 171 | ALOGI("Selected wakeup count\n"); |
| 172 | return &autosuspend_wakeup_count_ops; |
| 173 | |
| 174 | err_pthread_create: |
| 175 | sem_destroy(&suspend_lockout); |
| 176 | err_sem_init: |
| 177 | close(wakeup_count_fd); |
| 178 | err_open_wakeup_count: |
| 179 | close(state_fd); |
| 180 | err_open_state: |
| 181 | return NULL; |
| 182 | } |