diff --git a/recovery_ui/ui.cpp b/recovery_ui/ui.cpp
new file mode 100644
index 0000000..b7107ff
--- /dev/null
+++ b/recovery_ui/ui.cpp
@@ -0,0 +1,597 @@
+/*
+ * Copyright (C) 2011 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 "recovery_ui/ui.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <chrono>
+#include <functional>
+#include <string>
+#include <thread>
+
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <android-base/parseint.h>
+#include <android-base/properties.h>
+#include <android-base/strings.h>
+
+#include "minui/minui.h"
+#include "otautil/sysutil.h"
+
+using namespace std::chrono_literals;
+
+constexpr int UI_WAIT_KEY_TIMEOUT_SEC = 120;
+constexpr const char* BRIGHTNESS_FILE = "/sys/class/leds/lcd-backlight/brightness";
+constexpr const char* MAX_BRIGHTNESS_FILE = "/sys/class/leds/lcd-backlight/max_brightness";
+constexpr const char* BRIGHTNESS_FILE_SDM = "/sys/class/backlight/panel0-backlight/brightness";
+constexpr const char* MAX_BRIGHTNESS_FILE_SDM =
+    "/sys/class/backlight/panel0-backlight/max_brightness";
+
+constexpr int kDefaultTouchLowThreshold = 50;
+constexpr int kDefaultTouchHighThreshold = 90;
+
+RecoveryUI::RecoveryUI()
+    : brightness_normal_(50),
+      brightness_dimmed_(25),
+      brightness_file_(BRIGHTNESS_FILE),
+      max_brightness_file_(MAX_BRIGHTNESS_FILE),
+      touch_screen_allowed_(false),
+      fastbootd_logo_enabled_(false),
+      touch_low_threshold_(android::base::GetIntProperty("ro.recovery.ui.touch_low_threshold",
+                                                         kDefaultTouchLowThreshold)),
+      touch_high_threshold_(android::base::GetIntProperty("ro.recovery.ui.touch_high_threshold",
+                                                          kDefaultTouchHighThreshold)),
+      key_interrupted_(false),
+      key_queue_len(0),
+      key_last_down(-1),
+      key_long_press(false),
+      key_down_count(0),
+      enable_reboot(true),
+      consecutive_power_keys(0),
+      last_key(-1),
+      has_power_key(false),
+      has_up_key(false),
+      has_down_key(false),
+      has_touch_screen(false),
+      touch_slot_(0),
+      is_bootreason_recovery_ui_(false),
+      screensaver_state_(ScreensaverState::DISABLED) {
+  memset(key_pressed, 0, sizeof(key_pressed));
+}
+
+RecoveryUI::~RecoveryUI() {
+  ev_exit();
+  input_thread_stopped_ = true;
+  if (input_thread_.joinable()) {
+    input_thread_.join();
+  }
+}
+
+void RecoveryUI::OnKeyDetected(int key_code) {
+  if (key_code == KEY_POWER) {
+    has_power_key = true;
+  } else if (key_code == KEY_DOWN || key_code == KEY_VOLUMEDOWN) {
+    has_down_key = true;
+  } else if (key_code == KEY_UP || key_code == KEY_VOLUMEUP) {
+    has_up_key = true;
+  } else if (key_code == ABS_MT_POSITION_X || key_code == ABS_MT_POSITION_Y) {
+    has_touch_screen = true;
+  }
+}
+
+bool RecoveryUI::InitScreensaver() {
+  // Disabled.
+  if (brightness_normal_ == 0 || brightness_dimmed_ > brightness_normal_) {
+    return false;
+  }
+  if (access(brightness_file_.c_str(), R_OK | W_OK)) {
+    brightness_file_ = BRIGHTNESS_FILE_SDM;
+  }
+  if (access(max_brightness_file_.c_str(), R_OK)) {
+    max_brightness_file_ = MAX_BRIGHTNESS_FILE_SDM;
+  }
+  // Set the initial brightness level based on the max brightness. Note that reading the initial
+  // value from BRIGHTNESS_FILE doesn't give the actual brightness value (bullhead, sailfish), so
+  // we don't have a good way to query the default value.
+  std::string content;
+  if (!android::base::ReadFileToString(max_brightness_file_, &content)) {
+    PLOG(WARNING) << "Failed to read max brightness";
+    return false;
+  }
+
+  unsigned int max_value;
+  if (!android::base::ParseUint(android::base::Trim(content), &max_value)) {
+    LOG(WARNING) << "Failed to parse max brightness: " << content;
+    return false;
+  }
+
+  brightness_normal_value_ = max_value * brightness_normal_ / 100.0;
+  brightness_dimmed_value_ = max_value * brightness_dimmed_ / 100.0;
+  if (!android::base::WriteStringToFile(std::to_string(brightness_normal_value_),
+                                        brightness_file_)) {
+    PLOG(WARNING) << "Failed to set brightness";
+    return false;
+  }
+
+  LOG(INFO) << "Brightness: " << brightness_normal_value_ << " (" << brightness_normal_ << "%)";
+  screensaver_state_ = ScreensaverState::NORMAL;
+  return true;
+}
+
+bool RecoveryUI::Init(const std::string& /* locale */) {
+  ev_init(std::bind(&RecoveryUI::OnInputEvent, this, std::placeholders::_1, std::placeholders::_2),
+          touch_screen_allowed_);
+
+  ev_iterate_available_keys(std::bind(&RecoveryUI::OnKeyDetected, this, std::placeholders::_1));
+
+  if (touch_screen_allowed_) {
+    ev_iterate_touch_inputs(std::bind(&RecoveryUI::OnKeyDetected, this, std::placeholders::_1));
+
+    // Parse /proc/cmdline to determine if it's booting into recovery with a bootreason of
+    // "recovery_ui". This specific reason is set by some (wear) bootloaders, to allow an easier way
+    // to turn on text mode. It will only be set if the recovery boot is triggered from fastboot, or
+    // with 'adb reboot recovery'. Note that this applies to all build variants. Otherwise the text
+    // mode will be turned on automatically on debuggable builds, even without a swipe.
+    std::string cmdline;
+    if (android::base::ReadFileToString("/proc/cmdline", &cmdline)) {
+      is_bootreason_recovery_ui_ = cmdline.find("bootreason=recovery_ui") != std::string::npos;
+    } else {
+      // Non-fatal, and won't affect Init() result.
+      PLOG(WARNING) << "Failed to read /proc/cmdline";
+    }
+  }
+
+  if (!InitScreensaver()) {
+    LOG(INFO) << "Screensaver disabled";
+  }
+
+  // Create a separate thread that handles input events.
+  input_thread_ = std::thread([this]() {
+    while (!this->input_thread_stopped_) {
+      if (!ev_wait(500)) {
+        ev_dispatch();
+      }
+    }
+  });
+
+  return true;
+}
+
+void RecoveryUI::OnTouchDetected(int dx, int dy) {
+  enum SwipeDirection { UP, DOWN, RIGHT, LEFT } direction;
+
+  // We only consider a valid swipe if:
+  // - the delta along one axis is below touch_low_threshold_;
+  // - and the delta along the other axis is beyond touch_high_threshold_.
+  if (abs(dy) < touch_low_threshold_ && abs(dx) > touch_high_threshold_) {
+    direction = dx < 0 ? SwipeDirection::LEFT : SwipeDirection::RIGHT;
+  } else if (abs(dx) < touch_low_threshold_ && abs(dy) > touch_high_threshold_) {
+    direction = dy < 0 ? SwipeDirection::UP : SwipeDirection::DOWN;
+  } else {
+    LOG(DEBUG) << "Ignored " << dx << " " << dy << " (low: " << touch_low_threshold_
+               << ", high: " << touch_high_threshold_ << ")";
+    return;
+  }
+
+  // Allow turning on text mode with any swipe, if bootloader has set a bootreason of recovery_ui.
+  if (is_bootreason_recovery_ui_ && !IsTextVisible()) {
+    ShowText(true);
+    return;
+  }
+
+  LOG(DEBUG) << "Swipe direction=" << direction;
+  switch (direction) {
+    case SwipeDirection::UP:
+      ProcessKey(KEY_UP, 1);  // press up key
+      ProcessKey(KEY_UP, 0);  // and release it
+      break;
+
+    case SwipeDirection::DOWN:
+      ProcessKey(KEY_DOWN, 1);  // press down key
+      ProcessKey(KEY_DOWN, 0);  // and release it
+      break;
+
+    case SwipeDirection::LEFT:
+    case SwipeDirection::RIGHT:
+      ProcessKey(KEY_POWER, 1);  // press power key
+      ProcessKey(KEY_POWER, 0);  // and release it
+      break;
+  };
+}
+
+int RecoveryUI::OnInputEvent(int fd, uint32_t epevents) {
+  struct input_event ev;
+  if (ev_get_input(fd, epevents, &ev) == -1) {
+    return -1;
+  }
+
+  // Touch inputs handling.
+  //
+  // We handle the touch inputs by tracking the position changes between initial contacting and
+  // upon lifting. touch_start_X/Y record the initial positions, with touch_finger_down set. Upon
+  // detecting the lift, we unset touch_finger_down and detect a swipe based on position changes.
+  //
+  // Per the doc Multi-touch Protocol at below, there are two protocols.
+  // https://www.kernel.org/doc/Documentation/input/multi-touch-protocol.txt
+  //
+  // The main difference between the stateless type A protocol and the stateful type B slot protocol
+  // lies in the usage of identifiable contacts to reduce the amount of data sent to userspace. The
+  // slot protocol (i.e. type B) sends ABS_MT_TRACKING_ID with a unique id on initial contact, and
+  // sends ABS_MT_TRACKING_ID -1 upon lifting the contact. Protocol A doesn't send
+  // ABS_MT_TRACKING_ID -1 on lifting, but the driver may additionally report BTN_TOUCH event.
+  //
+  // For protocol A, we rely on BTN_TOUCH to recognize lifting, while for protocol B we look for
+  // ABS_MT_TRACKING_ID being -1.
+  //
+  // Touch input events will only be available if touch_screen_allowed_ is set.
+
+  if (ev.type == EV_SYN) {
+    if (touch_screen_allowed_ && ev.code == SYN_REPORT) {
+      // There might be multiple SYN_REPORT events. We should only detect a swipe after lifting the
+      // contact.
+      if (touch_finger_down_ && !touch_swiping_) {
+        touch_start_X_ = touch_X_;
+        touch_start_Y_ = touch_Y_;
+        touch_swiping_ = true;
+      } else if (!touch_finger_down_ && touch_swiping_) {
+        touch_swiping_ = false;
+        OnTouchDetected(touch_X_ - touch_start_X_, touch_Y_ - touch_start_Y_);
+      }
+    }
+    return 0;
+  }
+
+  if (ev.type == EV_REL) {
+    if (ev.code == REL_Y) {
+      // accumulate the up or down motion reported by
+      // the trackball.  When it exceeds a threshold
+      // (positive or negative), fake an up/down
+      // key event.
+      rel_sum += ev.value;
+      if (rel_sum > 3) {
+        ProcessKey(KEY_DOWN, 1);  // press down key
+        ProcessKey(KEY_DOWN, 0);  // and release it
+        rel_sum = 0;
+      } else if (rel_sum < -3) {
+        ProcessKey(KEY_UP, 1);  // press up key
+        ProcessKey(KEY_UP, 0);  // and release it
+        rel_sum = 0;
+      }
+    }
+  } else {
+    rel_sum = 0;
+  }
+
+  if (touch_screen_allowed_ && ev.type == EV_ABS) {
+    if (ev.code == ABS_MT_SLOT) {
+      touch_slot_ = ev.value;
+    }
+    // Ignore other fingers.
+    if (touch_slot_ > 0) return 0;
+
+    switch (ev.code) {
+      case ABS_MT_POSITION_X:
+        touch_X_ = ev.value;
+        touch_finger_down_ = true;
+        break;
+
+      case ABS_MT_POSITION_Y:
+        touch_Y_ = ev.value;
+        touch_finger_down_ = true;
+        break;
+
+      case ABS_MT_TRACKING_ID:
+        // Protocol B: -1 marks lifting the contact.
+        if (ev.value < 0) touch_finger_down_ = false;
+        break;
+    }
+    return 0;
+  }
+
+  if (ev.type == EV_KEY && ev.code <= KEY_MAX) {
+    if (touch_screen_allowed_) {
+      if (ev.code == BTN_TOUCH) {
+        // A BTN_TOUCH with value 1 indicates the start of contact (protocol A), with 0 means
+        // lifting the contact.
+        touch_finger_down_ = (ev.value == 1);
+      }
+
+      // Intentionally ignore BTN_TOUCH and BTN_TOOL_FINGER, which would otherwise trigger
+      // additional scrolling (because in ScreenRecoveryUI::ShowFile(), we consider keys other than
+      // KEY_POWER and KEY_UP as KEY_DOWN).
+      if (ev.code == BTN_TOUCH || ev.code == BTN_TOOL_FINGER) {
+        return 0;
+      }
+    }
+
+    ProcessKey(ev.code, ev.value);
+  }
+
+  return 0;
+}
+
+// Processes a key-up or -down event. A key is "registered" when it is pressed and then released,
+// with no other keypresses or releases in between. Registered keys are passed to CheckKey() to
+// see if it should trigger a visibility toggle, an immediate reboot, or be queued to be processed
+// next time the foreground thread wants a key (eg, for the menu).
+//
+// We also keep track of which keys are currently down so that CheckKey() can call IsKeyPressed()
+// to see what other keys are held when a key is registered.
+//
+// updown == 1 for key down events; 0 for key up events
+void RecoveryUI::ProcessKey(int key_code, int updown) {
+  bool register_key = false;
+  bool long_press = false;
+
+  {
+    std::lock_guard<std::mutex> lg(key_queue_mutex);
+    key_pressed[key_code] = updown;
+    if (updown) {
+      ++key_down_count;
+      key_last_down = key_code;
+      key_long_press = false;
+      std::thread time_key_thread(&RecoveryUI::TimeKey, this, key_code, key_down_count);
+      time_key_thread.detach();
+    } else {
+      if (key_last_down == key_code) {
+        long_press = key_long_press;
+        register_key = true;
+      }
+      key_last_down = -1;
+    }
+  }
+
+  bool reboot_enabled = enable_reboot;
+  if (register_key) {
+    switch (CheckKey(key_code, long_press)) {
+      case RecoveryUI::IGNORE:
+        break;
+
+      case RecoveryUI::TOGGLE:
+        ShowText(!IsTextVisible());
+        break;
+
+      case RecoveryUI::REBOOT:
+        if (reboot_enabled) {
+          reboot("reboot,");
+          while (true) {
+            pause();
+          }
+        }
+        break;
+
+      case RecoveryUI::ENQUEUE:
+        EnqueueKey(key_code);
+        break;
+    }
+  }
+}
+
+void RecoveryUI::TimeKey(int key_code, int count) {
+  std::this_thread::sleep_for(750ms);  // 750 ms == "long"
+  bool long_press = false;
+  {
+    std::lock_guard<std::mutex> lg(key_queue_mutex);
+    if (key_last_down == key_code && key_down_count == count) {
+      long_press = key_long_press = true;
+    }
+  }
+  if (long_press) KeyLongPress(key_code);
+}
+
+void RecoveryUI::EnqueueKey(int key_code) {
+  std::lock_guard<std::mutex> lg(key_queue_mutex);
+  const int queue_max = sizeof(key_queue) / sizeof(key_queue[0]);
+  if (key_queue_len < queue_max) {
+    key_queue[key_queue_len++] = key_code;
+    key_queue_cond.notify_one();
+  }
+}
+
+void RecoveryUI::SetScreensaverState(ScreensaverState state) {
+  switch (state) {
+    case ScreensaverState::NORMAL:
+      if (android::base::WriteStringToFile(std::to_string(brightness_normal_value_),
+                                           brightness_file_)) {
+        screensaver_state_ = ScreensaverState::NORMAL;
+        LOG(INFO) << "Brightness: " << brightness_normal_value_ << " (" << brightness_normal_
+                  << "%)";
+      } else {
+        LOG(ERROR) << "Unable to set brightness to normal";
+      }
+      break;
+    case ScreensaverState::DIMMED:
+      if (android::base::WriteStringToFile(std::to_string(brightness_dimmed_value_),
+                                           brightness_file_)) {
+        LOG(INFO) << "Brightness: " << brightness_dimmed_value_ << " (" << brightness_dimmed_
+                  << "%)";
+        screensaver_state_ = ScreensaverState::DIMMED;
+      } else {
+        LOG(ERROR) << "Unable to set brightness to dim";
+      }
+      break;
+    case ScreensaverState::OFF:
+      if (android::base::WriteStringToFile("0", brightness_file_)) {
+        LOG(INFO) << "Brightness: 0 (off)";
+        screensaver_state_ = ScreensaverState::OFF;
+      } else {
+        LOG(ERROR) << "Unable to set brightness to off";
+      }
+      break;
+    default:
+      LOG(ERROR) << "Invalid screensaver state";
+  }
+}
+
+int RecoveryUI::WaitKey() {
+  std::unique_lock<std::mutex> lk(key_queue_mutex);
+
+  // Check for a saved key queue interruption.
+  if (key_interrupted_) {
+    SetScreensaverState(ScreensaverState::NORMAL);
+    return static_cast<int>(KeyError::INTERRUPTED);
+  }
+
+  // Time out after UI_WAIT_KEY_TIMEOUT_SEC, unless a USB cable is plugged in.
+  do {
+    bool rc = key_queue_cond.wait_for(lk, std::chrono::seconds(UI_WAIT_KEY_TIMEOUT_SEC), [this] {
+      return this->key_queue_len != 0 || key_interrupted_;
+    });
+    if (key_interrupted_) {
+      SetScreensaverState(ScreensaverState::NORMAL);
+      return static_cast<int>(KeyError::INTERRUPTED);
+    }
+    if (screensaver_state_ != ScreensaverState::DISABLED) {
+      if (!rc) {
+        // Must be after a timeout. Lower the brightness level: NORMAL -> DIMMED; DIMMED -> OFF.
+        if (screensaver_state_ == ScreensaverState::NORMAL) {
+          SetScreensaverState(ScreensaverState::DIMMED);
+        } else if (screensaver_state_ == ScreensaverState::DIMMED) {
+          SetScreensaverState(ScreensaverState::OFF);
+        }
+      } else if (screensaver_state_ != ScreensaverState::NORMAL) {
+        // Drop the first key if it's changing from OFF to NORMAL.
+        if (screensaver_state_ == ScreensaverState::OFF) {
+          if (key_queue_len > 0) {
+            memcpy(&key_queue[0], &key_queue[1], sizeof(int) * --key_queue_len);
+          }
+        }
+
+        // Reset the brightness to normal.
+        SetScreensaverState(ScreensaverState::NORMAL);
+      }
+    }
+  } while (IsUsbConnected() && key_queue_len == 0);
+
+  int key = static_cast<int>(KeyError::TIMED_OUT);
+  if (key_queue_len > 0) {
+    key = key_queue[0];
+    memcpy(&key_queue[0], &key_queue[1], sizeof(int) * --key_queue_len);
+  }
+  return key;
+}
+
+void RecoveryUI::InterruptKey() {
+  {
+    std::lock_guard<std::mutex> lg(key_queue_mutex);
+    key_interrupted_ = true;
+  }
+  key_queue_cond.notify_one();
+}
+
+bool RecoveryUI::IsUsbConnected() {
+  int fd = open("/sys/class/android_usb/android0/state", O_RDONLY);
+  if (fd < 0) {
+    printf("failed to open /sys/class/android_usb/android0/state: %s\n", strerror(errno));
+    return 0;
+  }
+
+  char buf;
+  // USB is connected if android_usb state is CONNECTED or CONFIGURED.
+  int connected = (TEMP_FAILURE_RETRY(read(fd, &buf, 1)) == 1) && (buf == 'C');
+  if (close(fd) < 0) {
+    printf("failed to close /sys/class/android_usb/android0/state: %s\n", strerror(errno));
+  }
+  return connected;
+}
+
+bool RecoveryUI::IsKeyPressed(int key) {
+  std::lock_guard<std::mutex> lg(key_queue_mutex);
+  int pressed = key_pressed[key];
+  return pressed;
+}
+
+bool RecoveryUI::IsLongPress() {
+  std::lock_guard<std::mutex> lg(key_queue_mutex);
+  bool result = key_long_press;
+  return result;
+}
+
+bool RecoveryUI::HasThreeButtons() {
+  return has_power_key && has_up_key && has_down_key;
+}
+
+bool RecoveryUI::HasPowerKey() const {
+  return has_power_key;
+}
+
+bool RecoveryUI::HasTouchScreen() const {
+  return has_touch_screen;
+}
+
+void RecoveryUI::FlushKeys() {
+  std::lock_guard<std::mutex> lg(key_queue_mutex);
+  key_queue_len = 0;
+}
+
+RecoveryUI::KeyAction RecoveryUI::CheckKey(int key, bool is_long_press) {
+  {
+    std::lock_guard<std::mutex> lg(key_queue_mutex);
+    key_long_press = false;
+  }
+
+  // If we have power and volume up keys, that chord is the signal to toggle the text display.
+  if (HasThreeButtons() || (HasPowerKey() && HasTouchScreen() && touch_screen_allowed_)) {
+    if ((key == KEY_VOLUMEUP || key == KEY_UP) && IsKeyPressed(KEY_POWER)) {
+      return TOGGLE;
+    }
+  } else {
+    // Otherwise long press of any button toggles to the text display,
+    // and there's no way to toggle back (but that's pretty useless anyway).
+    if (is_long_press && !IsTextVisible()) {
+      return TOGGLE;
+    }
+
+    // Also, for button-limited devices, a long press is translated to KEY_ENTER.
+    if (is_long_press && IsTextVisible()) {
+      EnqueueKey(KEY_ENTER);
+      return IGNORE;
+    }
+  }
+
+  // Press power seven times in a row to reboot.
+  if (key == KEY_POWER) {
+    bool reboot_enabled = enable_reboot;
+
+    if (reboot_enabled) {
+      ++consecutive_power_keys;
+      if (consecutive_power_keys >= 7) {
+        return REBOOT;
+      }
+    }
+  } else {
+    consecutive_power_keys = 0;
+  }
+
+  last_key = key;
+  return (IsTextVisible() || screensaver_state_ == ScreensaverState::OFF) ? ENQUEUE : IGNORE;
+}
+
+void RecoveryUI::KeyLongPress(int) {}
+
+void RecoveryUI::SetEnableReboot(bool enabled) {
+  std::lock_guard<std::mutex> lg(key_queue_mutex);
+  enable_reboot = enabled;
+}