text: /*
   * Copyright (C) 2020 The LineageOS 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 <aidl/android/hardware/power/BnPower.h>
  #include <android-base/file.h>
  #include <android-base/logging.h>
  #include <linux/input.h>
  
  namespace {
  int open_ts_input() {
      int fd = -1;
      DIR* dir = opendir("/dev/input");
  
      if (dir != NULL) {
          struct dirent* ent;
  
          while ((ent = readdir(dir)) != NULL) {
              if (ent->d_type == DT_CHR) {
                  char absolute_path[PATH_MAX] = {0};
                  char name[80] = {0};
  
                  strcpy(absolute_path, "/dev/input/");
                  strcat(absolute_path, ent->d_name);
  
                  fd = open(absolute_path, O_RDWR);
                  if (ioctl(fd, EVIOCGNAME(sizeof(name) - 1), &name) > 0) {
                      if (strcmp(name, "fts_ts") == 0)
                          break;
                  }
  
                  close(fd);
                  fd = -1;
              }
          }
  
          closedir(dir);
      }
  
      return fd;
  }
  }  // anonymous namespace
  
  namespace aidl {
  namespace android {
  namespace hardware {
  namespace power {
  namespace impl {
  
  static constexpr int kInputEventWakeupModeOff = 4;
  static constexpr int kInputEventWakeupModeOn = 5;
  
  using ::aidl::android::hardware::power::Mode;
  
  bool isDeviceSpecificModeSupported(Mode type, bool* _aidl_return) {
      switch (type) {
          case Mode::DOUBLE_TAP_TO_WAKE:
              *_aidl_return = true;
              return true;
          default:
              return false;
      }
  }
  
  bool setDeviceSpecificMode(Mode type, bool enabled) {
      switch (type) {
          case Mode::DOUBLE_TAP_TO_WAKE: {
              int fd = open_ts_input();
              if (fd == -1) {
                  LOG(WARNING)
                      << "DT2W won't work because no supported touchscreen input devices were found";
                  return false;
              }
              struct input_event ev;
              ev.type = EV_SYN;
              ev.code = SYN_CONFIG;
              ev.value = enabled ? kInputEventWakeupModeOff : kInputEventWakeupModeOn;
              write(fd, &ev, sizeof(ev));
              close(fd);
          }
              return true;
          default:
              return false;
      }
  }
  
  }  // namespace impl
  }  // namespace power
  }  // namespace hardware
  }  // namespace android
  }  // namespace aidl