Create inputreader directory

In order to start the work to split InputReader.cpp into multiple files,
we first create a reader directory to hold the source files for
libinputreader.

The affected files are also reformatted with clang-format.

Bug: 140139676
Test: libinputflinger and libinputflinger_tests builds successfully for
  crosshatch

Change-Id: I62b6b873e2a03e61655eb6214183c984306dcfdb
diff --git a/services/inputflinger/reader/EventHub.cpp b/services/inputflinger/reader/EventHub.cpp
new file mode 100644
index 0000000..c15ecfd
--- /dev/null
+++ b/services/inputflinger/reader/EventHub.cpp
@@ -0,0 +1,1945 @@
+/*
+ * Copyright (C) 2005 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 <assert.h>
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <memory.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/epoll.h>
+#include <sys/inotify.h>
+#include <sys/ioctl.h>
+#include <sys/limits.h>
+#include <unistd.h>
+
+#define LOG_TAG "EventHub"
+
+// #define LOG_NDEBUG 0
+
+#include "EventHub.h"
+
+#include <hardware_legacy/power.h>
+
+#include <android-base/stringprintf.h>
+#include <cutils/properties.h>
+#include <openssl/sha.h>
+#include <utils/Errors.h>
+#include <utils/Log.h>
+#include <utils/Timers.h>
+#include <utils/threads.h>
+
+#include <input/KeyCharacterMap.h>
+#include <input/KeyLayoutMap.h>
+#include <input/VirtualKeyMap.h>
+
+/* this macro is used to tell if "bit" is set in "array"
+ * it selects a byte from the array, and does a boolean AND
+ * operation with a byte that only has the relevant bit set.
+ * eg. to check for the 12th bit, we do (array[1] & 1<<4)
+ */
+#define test_bit(bit, array) ((array)[(bit) / 8] & (1 << ((bit) % 8)))
+
+/* this macro computes the number of bytes needed to represent a bit array of the specified size */
+#define sizeof_bit_array(bits) (((bits) + 7) / 8)
+
+#define INDENT "  "
+#define INDENT2 "    "
+#define INDENT3 "      "
+
+using android::base::StringPrintf;
+
+namespace android {
+
+static constexpr bool DEBUG = false;
+
+static const char* WAKE_LOCK_ID = "KeyEvents";
+static const char* DEVICE_PATH = "/dev/input";
+// v4l2 devices go directly into /dev
+static const char* VIDEO_DEVICE_PATH = "/dev";
+
+static inline const char* toString(bool value) {
+    return value ? "true" : "false";
+}
+
+static std::string sha1(const std::string& in) {
+    SHA_CTX ctx;
+    SHA1_Init(&ctx);
+    SHA1_Update(&ctx, reinterpret_cast<const u_char*>(in.c_str()), in.size());
+    u_char digest[SHA_DIGEST_LENGTH];
+    SHA1_Final(digest, &ctx);
+
+    std::string out;
+    for (size_t i = 0; i < SHA_DIGEST_LENGTH; i++) {
+        out += StringPrintf("%02x", digest[i]);
+    }
+    return out;
+}
+
+/**
+ * Return true if name matches "v4l-touch*"
+ */
+static bool isV4lTouchNode(const char* name) {
+    return strstr(name, "v4l-touch") == name;
+}
+
+/**
+ * Returns true if V4L devices should be scanned.
+ *
+ * The system property ro.input.video_enabled can be used to control whether
+ * EventHub scans and opens V4L devices. As V4L does not support multiple
+ * clients, EventHub effectively blocks access to these devices when it opens
+ * them.
+ *
+ * Setting this to "false" would prevent any video devices from being discovered and
+ * associated with input devices.
+ *
+ * This property can be used as follows:
+ * 1. To turn off features that are dependent on video device presence.
+ * 2. During testing and development, to allow other clients to read video devices
+ * directly from /dev.
+ */
+static bool isV4lScanningEnabled() {
+    return property_get_bool("ro.input.video_enabled", true /* default_value */);
+}
+
+static nsecs_t processEventTimestamp(const struct input_event& event) {
+    // Use the time specified in the event instead of the current time
+    // so that downstream code can get more accurate estimates of
+    // event dispatch latency from the time the event is enqueued onto
+    // the evdev client buffer.
+    //
+    // The event's timestamp fortuitously uses the same monotonic clock
+    // time base as the rest of Android. The kernel event device driver
+    // (drivers/input/evdev.c) obtains timestamps using ktime_get_ts().
+    // The systemTime(SYSTEM_TIME_MONOTONIC) function we use everywhere
+    // calls clock_gettime(CLOCK_MONOTONIC) which is implemented as a
+    // system call that also queries ktime_get_ts().
+
+    const nsecs_t inputEventTime = seconds_to_nanoseconds(event.time.tv_sec) +
+            microseconds_to_nanoseconds(event.time.tv_usec);
+    return inputEventTime;
+}
+
+// --- Global Functions ---
+
+uint32_t getAbsAxisUsage(int32_t axis, uint32_t deviceClasses) {
+    // Touch devices get dibs on touch-related axes.
+    if (deviceClasses & INPUT_DEVICE_CLASS_TOUCH) {
+        switch (axis) {
+            case ABS_X:
+            case ABS_Y:
+            case ABS_PRESSURE:
+            case ABS_TOOL_WIDTH:
+            case ABS_DISTANCE:
+            case ABS_TILT_X:
+            case ABS_TILT_Y:
+            case ABS_MT_SLOT:
+            case ABS_MT_TOUCH_MAJOR:
+            case ABS_MT_TOUCH_MINOR:
+            case ABS_MT_WIDTH_MAJOR:
+            case ABS_MT_WIDTH_MINOR:
+            case ABS_MT_ORIENTATION:
+            case ABS_MT_POSITION_X:
+            case ABS_MT_POSITION_Y:
+            case ABS_MT_TOOL_TYPE:
+            case ABS_MT_BLOB_ID:
+            case ABS_MT_TRACKING_ID:
+            case ABS_MT_PRESSURE:
+            case ABS_MT_DISTANCE:
+                return INPUT_DEVICE_CLASS_TOUCH;
+        }
+    }
+
+    // External stylus gets the pressure axis
+    if (deviceClasses & INPUT_DEVICE_CLASS_EXTERNAL_STYLUS) {
+        if (axis == ABS_PRESSURE) {
+            return INPUT_DEVICE_CLASS_EXTERNAL_STYLUS;
+        }
+    }
+
+    // Joystick devices get the rest.
+    return deviceClasses & INPUT_DEVICE_CLASS_JOYSTICK;
+}
+
+// --- EventHub::Device ---
+
+EventHub::Device::Device(int fd, int32_t id, const std::string& path,
+                         const InputDeviceIdentifier& identifier)
+      : next(nullptr),
+        fd(fd),
+        id(id),
+        path(path),
+        identifier(identifier),
+        classes(0),
+        configuration(nullptr),
+        virtualKeyMap(nullptr),
+        ffEffectPlaying(false),
+        ffEffectId(-1),
+        controllerNumber(0),
+        enabled(true),
+        isVirtual(fd < 0) {
+    memset(keyBitmask, 0, sizeof(keyBitmask));
+    memset(absBitmask, 0, sizeof(absBitmask));
+    memset(relBitmask, 0, sizeof(relBitmask));
+    memset(swBitmask, 0, sizeof(swBitmask));
+    memset(ledBitmask, 0, sizeof(ledBitmask));
+    memset(ffBitmask, 0, sizeof(ffBitmask));
+    memset(propBitmask, 0, sizeof(propBitmask));
+}
+
+EventHub::Device::~Device() {
+    close();
+    delete configuration;
+}
+
+void EventHub::Device::close() {
+    if (fd >= 0) {
+        ::close(fd);
+        fd = -1;
+    }
+}
+
+status_t EventHub::Device::enable() {
+    fd = open(path.c_str(), O_RDWR | O_CLOEXEC | O_NONBLOCK);
+    if (fd < 0) {
+        ALOGE("could not open %s, %s\n", path.c_str(), strerror(errno));
+        return -errno;
+    }
+    enabled = true;
+    return OK;
+}
+
+status_t EventHub::Device::disable() {
+    close();
+    enabled = false;
+    return OK;
+}
+
+bool EventHub::Device::hasValidFd() {
+    return !isVirtual && enabled;
+}
+
+// --- EventHub ---
+
+const int EventHub::EPOLL_MAX_EVENTS;
+
+EventHub::EventHub(void)
+      : mBuiltInKeyboardId(NO_BUILT_IN_KEYBOARD),
+        mNextDeviceId(1),
+        mControllerNumbers(),
+        mOpeningDevices(nullptr),
+        mClosingDevices(nullptr),
+        mNeedToSendFinishedDeviceScan(false),
+        mNeedToReopenDevices(false),
+        mNeedToScanDevices(true),
+        mPendingEventCount(0),
+        mPendingEventIndex(0),
+        mPendingINotify(false) {
+    acquire_wake_lock(PARTIAL_WAKE_LOCK, WAKE_LOCK_ID);
+
+    mEpollFd = epoll_create1(EPOLL_CLOEXEC);
+    LOG_ALWAYS_FATAL_IF(mEpollFd < 0, "Could not create epoll instance: %s", strerror(errno));
+
+    mINotifyFd = inotify_init();
+    mInputWd = inotify_add_watch(mINotifyFd, DEVICE_PATH, IN_DELETE | IN_CREATE);
+    LOG_ALWAYS_FATAL_IF(mInputWd < 0, "Could not register INotify for %s: %s", DEVICE_PATH,
+                        strerror(errno));
+    if (isV4lScanningEnabled()) {
+        mVideoWd = inotify_add_watch(mINotifyFd, VIDEO_DEVICE_PATH, IN_DELETE | IN_CREATE);
+        LOG_ALWAYS_FATAL_IF(mVideoWd < 0, "Could not register INotify for %s: %s",
+                            VIDEO_DEVICE_PATH, strerror(errno));
+    } else {
+        mVideoWd = -1;
+        ALOGI("Video device scanning disabled");
+    }
+
+    struct epoll_event eventItem;
+    memset(&eventItem, 0, sizeof(eventItem));
+    eventItem.events = EPOLLIN;
+    eventItem.data.fd = mINotifyFd;
+    int result = epoll_ctl(mEpollFd, EPOLL_CTL_ADD, mINotifyFd, &eventItem);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not add INotify to epoll instance.  errno=%d", errno);
+
+    int wakeFds[2];
+    result = pipe(wakeFds);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not create wake pipe.  errno=%d", errno);
+
+    mWakeReadPipeFd = wakeFds[0];
+    mWakeWritePipeFd = wakeFds[1];
+
+    result = fcntl(mWakeReadPipeFd, F_SETFL, O_NONBLOCK);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not make wake read pipe non-blocking.  errno=%d",
+                        errno);
+
+    result = fcntl(mWakeWritePipeFd, F_SETFL, O_NONBLOCK);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not make wake write pipe non-blocking.  errno=%d",
+                        errno);
+
+    eventItem.data.fd = mWakeReadPipeFd;
+    result = epoll_ctl(mEpollFd, EPOLL_CTL_ADD, mWakeReadPipeFd, &eventItem);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not add wake read pipe to epoll instance.  errno=%d",
+                        errno);
+}
+
+EventHub::~EventHub(void) {
+    closeAllDevicesLocked();
+
+    while (mClosingDevices) {
+        Device* device = mClosingDevices;
+        mClosingDevices = device->next;
+        delete device;
+    }
+
+    ::close(mEpollFd);
+    ::close(mINotifyFd);
+    ::close(mWakeReadPipeFd);
+    ::close(mWakeWritePipeFd);
+
+    release_wake_lock(WAKE_LOCK_ID);
+}
+
+InputDeviceIdentifier EventHub::getDeviceIdentifier(int32_t deviceId) const {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device == nullptr) return InputDeviceIdentifier();
+    return device->identifier;
+}
+
+uint32_t EventHub::getDeviceClasses(int32_t deviceId) const {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device == nullptr) return 0;
+    return device->classes;
+}
+
+int32_t EventHub::getDeviceControllerNumber(int32_t deviceId) const {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device == nullptr) return 0;
+    return device->controllerNumber;
+}
+
+void EventHub::getConfiguration(int32_t deviceId, PropertyMap* outConfiguration) const {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device && device->configuration) {
+        *outConfiguration = *device->configuration;
+    } else {
+        outConfiguration->clear();
+    }
+}
+
+status_t EventHub::getAbsoluteAxisInfo(int32_t deviceId, int axis,
+                                       RawAbsoluteAxisInfo* outAxisInfo) const {
+    outAxisInfo->clear();
+
+    if (axis >= 0 && axis <= ABS_MAX) {
+        AutoMutex _l(mLock);
+
+        Device* device = getDeviceLocked(deviceId);
+        if (device && device->hasValidFd() && test_bit(axis, device->absBitmask)) {
+            struct input_absinfo info;
+            if (ioctl(device->fd, EVIOCGABS(axis), &info)) {
+                ALOGW("Error reading absolute controller %d for device %s fd %d, errno=%d", axis,
+                      device->identifier.name.c_str(), device->fd, errno);
+                return -errno;
+            }
+
+            if (info.minimum != info.maximum) {
+                outAxisInfo->valid = true;
+                outAxisInfo->minValue = info.minimum;
+                outAxisInfo->maxValue = info.maximum;
+                outAxisInfo->flat = info.flat;
+                outAxisInfo->fuzz = info.fuzz;
+                outAxisInfo->resolution = info.resolution;
+            }
+            return OK;
+        }
+    }
+    return -1;
+}
+
+bool EventHub::hasRelativeAxis(int32_t deviceId, int axis) const {
+    if (axis >= 0 && axis <= REL_MAX) {
+        AutoMutex _l(mLock);
+
+        Device* device = getDeviceLocked(deviceId);
+        if (device) {
+            return test_bit(axis, device->relBitmask);
+        }
+    }
+    return false;
+}
+
+bool EventHub::hasInputProperty(int32_t deviceId, int property) const {
+    if (property >= 0 && property <= INPUT_PROP_MAX) {
+        AutoMutex _l(mLock);
+
+        Device* device = getDeviceLocked(deviceId);
+        if (device) {
+            return test_bit(property, device->propBitmask);
+        }
+    }
+    return false;
+}
+
+int32_t EventHub::getScanCodeState(int32_t deviceId, int32_t scanCode) const {
+    if (scanCode >= 0 && scanCode <= KEY_MAX) {
+        AutoMutex _l(mLock);
+
+        Device* device = getDeviceLocked(deviceId);
+        if (device && device->hasValidFd() && test_bit(scanCode, device->keyBitmask)) {
+            uint8_t keyState[sizeof_bit_array(KEY_MAX + 1)];
+            memset(keyState, 0, sizeof(keyState));
+            if (ioctl(device->fd, EVIOCGKEY(sizeof(keyState)), keyState) >= 0) {
+                return test_bit(scanCode, keyState) ? AKEY_STATE_DOWN : AKEY_STATE_UP;
+            }
+        }
+    }
+    return AKEY_STATE_UNKNOWN;
+}
+
+int32_t EventHub::getKeyCodeState(int32_t deviceId, int32_t keyCode) const {
+    AutoMutex _l(mLock);
+
+    Device* device = getDeviceLocked(deviceId);
+    if (device && device->hasValidFd() && device->keyMap.haveKeyLayout()) {
+        std::vector<int32_t> scanCodes;
+        device->keyMap.keyLayoutMap->findScanCodesForKey(keyCode, &scanCodes);
+        if (scanCodes.size() != 0) {
+            uint8_t keyState[sizeof_bit_array(KEY_MAX + 1)];
+            memset(keyState, 0, sizeof(keyState));
+            if (ioctl(device->fd, EVIOCGKEY(sizeof(keyState)), keyState) >= 0) {
+                for (size_t i = 0; i < scanCodes.size(); i++) {
+                    int32_t sc = scanCodes[i];
+                    if (sc >= 0 && sc <= KEY_MAX && test_bit(sc, keyState)) {
+                        return AKEY_STATE_DOWN;
+                    }
+                }
+                return AKEY_STATE_UP;
+            }
+        }
+    }
+    return AKEY_STATE_UNKNOWN;
+}
+
+int32_t EventHub::getSwitchState(int32_t deviceId, int32_t sw) const {
+    if (sw >= 0 && sw <= SW_MAX) {
+        AutoMutex _l(mLock);
+
+        Device* device = getDeviceLocked(deviceId);
+        if (device && device->hasValidFd() && test_bit(sw, device->swBitmask)) {
+            uint8_t swState[sizeof_bit_array(SW_MAX + 1)];
+            memset(swState, 0, sizeof(swState));
+            if (ioctl(device->fd, EVIOCGSW(sizeof(swState)), swState) >= 0) {
+                return test_bit(sw, swState) ? AKEY_STATE_DOWN : AKEY_STATE_UP;
+            }
+        }
+    }
+    return AKEY_STATE_UNKNOWN;
+}
+
+status_t EventHub::getAbsoluteAxisValue(int32_t deviceId, int32_t axis, int32_t* outValue) const {
+    *outValue = 0;
+
+    if (axis >= 0 && axis <= ABS_MAX) {
+        AutoMutex _l(mLock);
+
+        Device* device = getDeviceLocked(deviceId);
+        if (device && device->hasValidFd() && test_bit(axis, device->absBitmask)) {
+            struct input_absinfo info;
+            if (ioctl(device->fd, EVIOCGABS(axis), &info)) {
+                ALOGW("Error reading absolute controller %d for device %s fd %d, errno=%d", axis,
+                      device->identifier.name.c_str(), device->fd, errno);
+                return -errno;
+            }
+
+            *outValue = info.value;
+            return OK;
+        }
+    }
+    return -1;
+}
+
+bool EventHub::markSupportedKeyCodes(int32_t deviceId, size_t numCodes, const int32_t* keyCodes,
+                                     uint8_t* outFlags) const {
+    AutoMutex _l(mLock);
+
+    Device* device = getDeviceLocked(deviceId);
+    if (device && device->keyMap.haveKeyLayout()) {
+        std::vector<int32_t> scanCodes;
+        for (size_t codeIndex = 0; codeIndex < numCodes; codeIndex++) {
+            scanCodes.clear();
+
+            status_t err = device->keyMap.keyLayoutMap->findScanCodesForKey(keyCodes[codeIndex],
+                                                                            &scanCodes);
+            if (!err) {
+                // check the possible scan codes identified by the layout map against the
+                // map of codes actually emitted by the driver
+                for (size_t sc = 0; sc < scanCodes.size(); sc++) {
+                    if (test_bit(scanCodes[sc], device->keyBitmask)) {
+                        outFlags[codeIndex] = 1;
+                        break;
+                    }
+                }
+            }
+        }
+        return true;
+    }
+    return false;
+}
+
+status_t EventHub::mapKey(int32_t deviceId, int32_t scanCode, int32_t usageCode, int32_t metaState,
+                          int32_t* outKeycode, int32_t* outMetaState, uint32_t* outFlags) const {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    status_t status = NAME_NOT_FOUND;
+
+    if (device) {
+        // Check the key character map first.
+        sp<KeyCharacterMap> kcm = device->getKeyCharacterMap();
+        if (kcm != nullptr) {
+            if (!kcm->mapKey(scanCode, usageCode, outKeycode)) {
+                *outFlags = 0;
+                status = NO_ERROR;
+            }
+        }
+
+        // Check the key layout next.
+        if (status != NO_ERROR && device->keyMap.haveKeyLayout()) {
+            if (!device->keyMap.keyLayoutMap->mapKey(scanCode, usageCode, outKeycode, outFlags)) {
+                status = NO_ERROR;
+            }
+        }
+
+        if (status == NO_ERROR) {
+            if (kcm != nullptr) {
+                kcm->tryRemapKey(*outKeycode, metaState, outKeycode, outMetaState);
+            } else {
+                *outMetaState = metaState;
+            }
+        }
+    }
+
+    if (status != NO_ERROR) {
+        *outKeycode = 0;
+        *outFlags = 0;
+        *outMetaState = metaState;
+    }
+
+    return status;
+}
+
+status_t EventHub::mapAxis(int32_t deviceId, int32_t scanCode, AxisInfo* outAxisInfo) const {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+
+    if (device && device->keyMap.haveKeyLayout()) {
+        status_t err = device->keyMap.keyLayoutMap->mapAxis(scanCode, outAxisInfo);
+        if (err == NO_ERROR) {
+            return NO_ERROR;
+        }
+    }
+
+    return NAME_NOT_FOUND;
+}
+
+void EventHub::setExcludedDevices(const std::vector<std::string>& devices) {
+    AutoMutex _l(mLock);
+
+    mExcludedDevices = devices;
+}
+
+bool EventHub::hasScanCode(int32_t deviceId, int32_t scanCode) const {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device && scanCode >= 0 && scanCode <= KEY_MAX) {
+        if (test_bit(scanCode, device->keyBitmask)) {
+            return true;
+        }
+    }
+    return false;
+}
+
+bool EventHub::hasLed(int32_t deviceId, int32_t led) const {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    int32_t sc;
+    if (device && mapLed(device, led, &sc) == NO_ERROR) {
+        if (test_bit(sc, device->ledBitmask)) {
+            return true;
+        }
+    }
+    return false;
+}
+
+void EventHub::setLedState(int32_t deviceId, int32_t led, bool on) {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    setLedStateLocked(device, led, on);
+}
+
+void EventHub::setLedStateLocked(Device* device, int32_t led, bool on) {
+    int32_t sc;
+    if (device && device->hasValidFd() && mapLed(device, led, &sc) != NAME_NOT_FOUND) {
+        struct input_event ev;
+        ev.time.tv_sec = 0;
+        ev.time.tv_usec = 0;
+        ev.type = EV_LED;
+        ev.code = sc;
+        ev.value = on ? 1 : 0;
+
+        ssize_t nWrite;
+        do {
+            nWrite = write(device->fd, &ev, sizeof(struct input_event));
+        } while (nWrite == -1 && errno == EINTR);
+    }
+}
+
+void EventHub::getVirtualKeyDefinitions(int32_t deviceId,
+                                        std::vector<VirtualKeyDefinition>& outVirtualKeys) const {
+    outVirtualKeys.clear();
+
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device && device->virtualKeyMap) {
+        const std::vector<VirtualKeyDefinition> virtualKeys =
+                device->virtualKeyMap->getVirtualKeys();
+        outVirtualKeys.insert(outVirtualKeys.end(), virtualKeys.begin(), virtualKeys.end());
+    }
+}
+
+sp<KeyCharacterMap> EventHub::getKeyCharacterMap(int32_t deviceId) const {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device) {
+        return device->getKeyCharacterMap();
+    }
+    return nullptr;
+}
+
+bool EventHub::setKeyboardLayoutOverlay(int32_t deviceId, const sp<KeyCharacterMap>& map) {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device) {
+        if (map != device->overlayKeyMap) {
+            device->overlayKeyMap = map;
+            device->combinedKeyMap = KeyCharacterMap::combine(device->keyMap.keyCharacterMap, map);
+            return true;
+        }
+    }
+    return false;
+}
+
+static std::string generateDescriptor(InputDeviceIdentifier& identifier) {
+    std::string rawDescriptor;
+    rawDescriptor += StringPrintf(":%04x:%04x:", identifier.vendor, identifier.product);
+    // TODO add handling for USB devices to not uniqueify kbs that show up twice
+    if (!identifier.uniqueId.empty()) {
+        rawDescriptor += "uniqueId:";
+        rawDescriptor += identifier.uniqueId;
+    } else if (identifier.nonce != 0) {
+        rawDescriptor += StringPrintf("nonce:%04x", identifier.nonce);
+    }
+
+    if (identifier.vendor == 0 && identifier.product == 0) {
+        // If we don't know the vendor and product id, then the device is probably
+        // built-in so we need to rely on other information to uniquely identify
+        // the input device.  Usually we try to avoid relying on the device name or
+        // location but for built-in input device, they are unlikely to ever change.
+        if (!identifier.name.empty()) {
+            rawDescriptor += "name:";
+            rawDescriptor += identifier.name;
+        } else if (!identifier.location.empty()) {
+            rawDescriptor += "location:";
+            rawDescriptor += identifier.location;
+        }
+    }
+    identifier.descriptor = sha1(rawDescriptor);
+    return rawDescriptor;
+}
+
+void EventHub::assignDescriptorLocked(InputDeviceIdentifier& identifier) {
+    // Compute a device descriptor that uniquely identifies the device.
+    // The descriptor is assumed to be a stable identifier.  Its value should not
+    // change between reboots, reconnections, firmware updates or new releases
+    // of Android. In practice we sometimes get devices that cannot be uniquely
+    // identified. In this case we enforce uniqueness between connected devices.
+    // Ideally, we also want the descriptor to be short and relatively opaque.
+
+    identifier.nonce = 0;
+    std::string rawDescriptor = generateDescriptor(identifier);
+    if (identifier.uniqueId.empty()) {
+        // If it didn't have a unique id check for conflicts and enforce
+        // uniqueness if necessary.
+        while (getDeviceByDescriptorLocked(identifier.descriptor) != nullptr) {
+            identifier.nonce++;
+            rawDescriptor = generateDescriptor(identifier);
+        }
+    }
+    ALOGV("Created descriptor: raw=%s, cooked=%s", rawDescriptor.c_str(),
+          identifier.descriptor.c_str());
+}
+
+void EventHub::vibrate(int32_t deviceId, nsecs_t duration) {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device && device->hasValidFd()) {
+        ff_effect effect;
+        memset(&effect, 0, sizeof(effect));
+        effect.type = FF_RUMBLE;
+        effect.id = device->ffEffectId;
+        effect.u.rumble.strong_magnitude = 0xc000;
+        effect.u.rumble.weak_magnitude = 0xc000;
+        effect.replay.length = (duration + 999999LL) / 1000000LL;
+        effect.replay.delay = 0;
+        if (ioctl(device->fd, EVIOCSFF, &effect)) {
+            ALOGW("Could not upload force feedback effect to device %s due to error %d.",
+                  device->identifier.name.c_str(), errno);
+            return;
+        }
+        device->ffEffectId = effect.id;
+
+        struct input_event ev;
+        ev.time.tv_sec = 0;
+        ev.time.tv_usec = 0;
+        ev.type = EV_FF;
+        ev.code = device->ffEffectId;
+        ev.value = 1;
+        if (write(device->fd, &ev, sizeof(ev)) != sizeof(ev)) {
+            ALOGW("Could not start force feedback effect on device %s due to error %d.",
+                  device->identifier.name.c_str(), errno);
+            return;
+        }
+        device->ffEffectPlaying = true;
+    }
+}
+
+void EventHub::cancelVibrate(int32_t deviceId) {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device && device->hasValidFd()) {
+        if (device->ffEffectPlaying) {
+            device->ffEffectPlaying = false;
+
+            struct input_event ev;
+            ev.time.tv_sec = 0;
+            ev.time.tv_usec = 0;
+            ev.type = EV_FF;
+            ev.code = device->ffEffectId;
+            ev.value = 0;
+            if (write(device->fd, &ev, sizeof(ev)) != sizeof(ev)) {
+                ALOGW("Could not stop force feedback effect on device %s due to error %d.",
+                      device->identifier.name.c_str(), errno);
+                return;
+            }
+        }
+    }
+}
+
+EventHub::Device* EventHub::getDeviceByDescriptorLocked(const std::string& descriptor) const {
+    size_t size = mDevices.size();
+    for (size_t i = 0; i < size; i++) {
+        Device* device = mDevices.valueAt(i);
+        if (descriptor == device->identifier.descriptor) {
+            return device;
+        }
+    }
+    return nullptr;
+}
+
+EventHub::Device* EventHub::getDeviceLocked(int32_t deviceId) const {
+    if (deviceId == ReservedInputDeviceId::BUILT_IN_KEYBOARD_ID) {
+        deviceId = mBuiltInKeyboardId;
+    }
+    ssize_t index = mDevices.indexOfKey(deviceId);
+    return index >= 0 ? mDevices.valueAt(index) : NULL;
+}
+
+EventHub::Device* EventHub::getDeviceByPathLocked(const char* devicePath) const {
+    for (size_t i = 0; i < mDevices.size(); i++) {
+        Device* device = mDevices.valueAt(i);
+        if (device->path == devicePath) {
+            return device;
+        }
+    }
+    return nullptr;
+}
+
+/**
+ * The file descriptor could be either input device, or a video device (associated with a
+ * specific input device). Check both cases here, and return the device that this event
+ * belongs to. Caller can compare the fd's once more to determine event type.
+ * Looks through all input devices, and only attached video devices. Unattached video
+ * devices are ignored.
+ */
+EventHub::Device* EventHub::getDeviceByFdLocked(int fd) const {
+    for (size_t i = 0; i < mDevices.size(); i++) {
+        Device* device = mDevices.valueAt(i);
+        if (device->fd == fd) {
+            // This is an input device event
+            return device;
+        }
+        if (device->videoDevice && device->videoDevice->getFd() == fd) {
+            // This is a video device event
+            return device;
+        }
+    }
+    // We do not check mUnattachedVideoDevices here because they should not participate in epoll,
+    // and therefore should never be looked up by fd.
+    return nullptr;
+}
+
+size_t EventHub::getEvents(int timeoutMillis, RawEvent* buffer, size_t bufferSize) {
+    ALOG_ASSERT(bufferSize >= 1);
+
+    AutoMutex _l(mLock);
+
+    struct input_event readBuffer[bufferSize];
+
+    RawEvent* event = buffer;
+    size_t capacity = bufferSize;
+    bool awoken = false;
+    for (;;) {
+        nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
+
+        // Reopen input devices if needed.
+        if (mNeedToReopenDevices) {
+            mNeedToReopenDevices = false;
+
+            ALOGI("Reopening all input devices due to a configuration change.");
+
+            closeAllDevicesLocked();
+            mNeedToScanDevices = true;
+            break; // return to the caller before we actually rescan
+        }
+
+        // Report any devices that had last been added/removed.
+        while (mClosingDevices) {
+            Device* device = mClosingDevices;
+            ALOGV("Reporting device closed: id=%d, name=%s\n", device->id, device->path.c_str());
+            mClosingDevices = device->next;
+            event->when = now;
+            event->deviceId = (device->id == mBuiltInKeyboardId)
+                    ? ReservedInputDeviceId::BUILT_IN_KEYBOARD_ID
+                    : device->id;
+            event->type = DEVICE_REMOVED;
+            event += 1;
+            delete device;
+            mNeedToSendFinishedDeviceScan = true;
+            if (--capacity == 0) {
+                break;
+            }
+        }
+
+        if (mNeedToScanDevices) {
+            mNeedToScanDevices = false;
+            scanDevicesLocked();
+            mNeedToSendFinishedDeviceScan = true;
+        }
+
+        while (mOpeningDevices != nullptr) {
+            Device* device = mOpeningDevices;
+            ALOGV("Reporting device opened: id=%d, name=%s\n", device->id, device->path.c_str());
+            mOpeningDevices = device->next;
+            event->when = now;
+            event->deviceId = device->id == mBuiltInKeyboardId ? 0 : device->id;
+            event->type = DEVICE_ADDED;
+            event += 1;
+            mNeedToSendFinishedDeviceScan = true;
+            if (--capacity == 0) {
+                break;
+            }
+        }
+
+        if (mNeedToSendFinishedDeviceScan) {
+            mNeedToSendFinishedDeviceScan = false;
+            event->when = now;
+            event->type = FINISHED_DEVICE_SCAN;
+            event += 1;
+            if (--capacity == 0) {
+                break;
+            }
+        }
+
+        // Grab the next input event.
+        bool deviceChanged = false;
+        while (mPendingEventIndex < mPendingEventCount) {
+            const struct epoll_event& eventItem = mPendingEventItems[mPendingEventIndex++];
+            if (eventItem.data.fd == mINotifyFd) {
+                if (eventItem.events & EPOLLIN) {
+                    mPendingINotify = true;
+                } else {
+                    ALOGW("Received unexpected epoll event 0x%08x for INotify.", eventItem.events);
+                }
+                continue;
+            }
+
+            if (eventItem.data.fd == mWakeReadPipeFd) {
+                if (eventItem.events & EPOLLIN) {
+                    ALOGV("awoken after wake()");
+                    awoken = true;
+                    char buffer[16];
+                    ssize_t nRead;
+                    do {
+                        nRead = read(mWakeReadPipeFd, buffer, sizeof(buffer));
+                    } while ((nRead == -1 && errno == EINTR) || nRead == sizeof(buffer));
+                } else {
+                    ALOGW("Received unexpected epoll event 0x%08x for wake read pipe.",
+                          eventItem.events);
+                }
+                continue;
+            }
+
+            Device* device = getDeviceByFdLocked(eventItem.data.fd);
+            if (!device) {
+                ALOGE("Received unexpected epoll event 0x%08x for unknown fd %d.", eventItem.events,
+                      eventItem.data.fd);
+                ALOG_ASSERT(!DEBUG);
+                continue;
+            }
+            if (device->videoDevice && eventItem.data.fd == device->videoDevice->getFd()) {
+                if (eventItem.events & EPOLLIN) {
+                    size_t numFrames = device->videoDevice->readAndQueueFrames();
+                    if (numFrames == 0) {
+                        ALOGE("Received epoll event for video device %s, but could not read frame",
+                              device->videoDevice->getName().c_str());
+                    }
+                } else if (eventItem.events & EPOLLHUP) {
+                    // TODO(b/121395353) - consider adding EPOLLRDHUP
+                    ALOGI("Removing video device %s due to epoll hang-up event.",
+                          device->videoDevice->getName().c_str());
+                    unregisterVideoDeviceFromEpollLocked(*device->videoDevice);
+                    device->videoDevice = nullptr;
+                } else {
+                    ALOGW("Received unexpected epoll event 0x%08x for device %s.", eventItem.events,
+                          device->videoDevice->getName().c_str());
+                    ALOG_ASSERT(!DEBUG);
+                }
+                continue;
+            }
+            // This must be an input event
+            if (eventItem.events & EPOLLIN) {
+                int32_t readSize =
+                        read(device->fd, readBuffer, sizeof(struct input_event) * capacity);
+                if (readSize == 0 || (readSize < 0 && errno == ENODEV)) {
+                    // Device was removed before INotify noticed.
+                    ALOGW("could not get event, removed? (fd: %d size: %" PRId32
+                          " bufferSize: %zu capacity: %zu errno: %d)\n",
+                          device->fd, readSize, bufferSize, capacity, errno);
+                    deviceChanged = true;
+                    closeDeviceLocked(device);
+                } else if (readSize < 0) {
+                    if (errno != EAGAIN && errno != EINTR) {
+                        ALOGW("could not get event (errno=%d)", errno);
+                    }
+                } else if ((readSize % sizeof(struct input_event)) != 0) {
+                    ALOGE("could not get event (wrong size: %d)", readSize);
+                } else {
+                    int32_t deviceId = device->id == mBuiltInKeyboardId ? 0 : device->id;
+
+                    size_t count = size_t(readSize) / sizeof(struct input_event);
+                    for (size_t i = 0; i < count; i++) {
+                        struct input_event& iev = readBuffer[i];
+                        event->when = processEventTimestamp(iev);
+                        event->deviceId = deviceId;
+                        event->type = iev.type;
+                        event->code = iev.code;
+                        event->value = iev.value;
+                        event += 1;
+                        capacity -= 1;
+                    }
+                    if (capacity == 0) {
+                        // The result buffer is full.  Reset the pending event index
+                        // so we will try to read the device again on the next iteration.
+                        mPendingEventIndex -= 1;
+                        break;
+                    }
+                }
+            } else if (eventItem.events & EPOLLHUP) {
+                ALOGI("Removing device %s due to epoll hang-up event.",
+                      device->identifier.name.c_str());
+                deviceChanged = true;
+                closeDeviceLocked(device);
+            } else {
+                ALOGW("Received unexpected epoll event 0x%08x for device %s.", eventItem.events,
+                      device->identifier.name.c_str());
+            }
+        }
+
+        // readNotify() will modify the list of devices so this must be done after
+        // processing all other events to ensure that we read all remaining events
+        // before closing the devices.
+        if (mPendingINotify && mPendingEventIndex >= mPendingEventCount) {
+            mPendingINotify = false;
+            readNotifyLocked();
+            deviceChanged = true;
+        }
+
+        // Report added or removed devices immediately.
+        if (deviceChanged) {
+            continue;
+        }
+
+        // Return now if we have collected any events or if we were explicitly awoken.
+        if (event != buffer || awoken) {
+            break;
+        }
+
+        // Poll for events.  Mind the wake lock dance!
+        // We hold a wake lock at all times except during epoll_wait().  This works due to some
+        // subtle choreography.  When a device driver has pending (unread) events, it acquires
+        // a kernel wake lock.  However, once the last pending event has been read, the device
+        // driver will release the kernel wake lock.  To prevent the system from going to sleep
+        // when this happens, the EventHub holds onto its own user wake lock while the client
+        // is processing events.  Thus the system can only sleep if there are no events
+        // pending or currently being processed.
+        //
+        // The timeout is advisory only.  If the device is asleep, it will not wake just to
+        // service the timeout.
+        mPendingEventIndex = 0;
+
+        mLock.unlock(); // release lock before poll, must be before release_wake_lock
+        release_wake_lock(WAKE_LOCK_ID);
+
+        int pollResult = epoll_wait(mEpollFd, mPendingEventItems, EPOLL_MAX_EVENTS, timeoutMillis);
+
+        acquire_wake_lock(PARTIAL_WAKE_LOCK, WAKE_LOCK_ID);
+        mLock.lock(); // reacquire lock after poll, must be after acquire_wake_lock
+
+        if (pollResult == 0) {
+            // Timed out.
+            mPendingEventCount = 0;
+            break;
+        }
+
+        if (pollResult < 0) {
+            // An error occurred.
+            mPendingEventCount = 0;
+
+            // Sleep after errors to avoid locking up the system.
+            // Hopefully the error is transient.
+            if (errno != EINTR) {
+                ALOGW("poll failed (errno=%d)\n", errno);
+                usleep(100000);
+            }
+        } else {
+            // Some events occurred.
+            mPendingEventCount = size_t(pollResult);
+        }
+    }
+
+    // All done, return the number of events we read.
+    return event - buffer;
+}
+
+std::vector<TouchVideoFrame> EventHub::getVideoFrames(int32_t deviceId) {
+    AutoMutex _l(mLock);
+
+    Device* device = getDeviceLocked(deviceId);
+    if (!device || !device->videoDevice) {
+        return {};
+    }
+    return device->videoDevice->consumeFrames();
+}
+
+void EventHub::wake() {
+    ALOGV("wake() called");
+
+    ssize_t nWrite;
+    do {
+        nWrite = write(mWakeWritePipeFd, "W", 1);
+    } while (nWrite == -1 && errno == EINTR);
+
+    if (nWrite != 1 && errno != EAGAIN) {
+        ALOGW("Could not write wake signal: %s", strerror(errno));
+    }
+}
+
+void EventHub::scanDevicesLocked() {
+    status_t result = scanDirLocked(DEVICE_PATH);
+    if (result < 0) {
+        ALOGE("scan dir failed for %s", DEVICE_PATH);
+    }
+    if (isV4lScanningEnabled()) {
+        result = scanVideoDirLocked(VIDEO_DEVICE_PATH);
+        if (result != OK) {
+            ALOGE("scan video dir failed for %s", VIDEO_DEVICE_PATH);
+        }
+    }
+    if (mDevices.indexOfKey(ReservedInputDeviceId::VIRTUAL_KEYBOARD_ID) < 0) {
+        createVirtualKeyboardLocked();
+    }
+}
+
+// ----------------------------------------------------------------------------
+
+static bool containsNonZeroByte(const uint8_t* array, uint32_t startIndex, uint32_t endIndex) {
+    const uint8_t* end = array + endIndex;
+    array += startIndex;
+    while (array != end) {
+        if (*(array++) != 0) {
+            return true;
+        }
+    }
+    return false;
+}
+
+static const int32_t GAMEPAD_KEYCODES[] = {
+        AKEYCODE_BUTTON_A,      AKEYCODE_BUTTON_B,      AKEYCODE_BUTTON_C,    //
+        AKEYCODE_BUTTON_X,      AKEYCODE_BUTTON_Y,      AKEYCODE_BUTTON_Z,    //
+        AKEYCODE_BUTTON_L1,     AKEYCODE_BUTTON_R1,                           //
+        AKEYCODE_BUTTON_L2,     AKEYCODE_BUTTON_R2,                           //
+        AKEYCODE_BUTTON_THUMBL, AKEYCODE_BUTTON_THUMBR,                       //
+        AKEYCODE_BUTTON_START,  AKEYCODE_BUTTON_SELECT, AKEYCODE_BUTTON_MODE, //
+};
+
+status_t EventHub::registerFdForEpoll(int fd) {
+    // TODO(b/121395353) - consider adding EPOLLRDHUP
+    struct epoll_event eventItem = {};
+    eventItem.events = EPOLLIN | EPOLLWAKEUP;
+    eventItem.data.fd = fd;
+    if (epoll_ctl(mEpollFd, EPOLL_CTL_ADD, fd, &eventItem)) {
+        ALOGE("Could not add fd to epoll instance: %s", strerror(errno));
+        return -errno;
+    }
+    return OK;
+}
+
+status_t EventHub::unregisterFdFromEpoll(int fd) {
+    if (epoll_ctl(mEpollFd, EPOLL_CTL_DEL, fd, nullptr)) {
+        ALOGW("Could not remove fd from epoll instance: %s", strerror(errno));
+        return -errno;
+    }
+    return OK;
+}
+
+status_t EventHub::registerDeviceForEpollLocked(Device* device) {
+    if (device == nullptr) {
+        if (DEBUG) {
+            LOG_ALWAYS_FATAL("Cannot call registerDeviceForEpollLocked with null Device");
+        }
+        return BAD_VALUE;
+    }
+    status_t result = registerFdForEpoll(device->fd);
+    if (result != OK) {
+        ALOGE("Could not add input device fd to epoll for device %" PRId32, device->id);
+        return result;
+    }
+    if (device->videoDevice) {
+        registerVideoDeviceForEpollLocked(*device->videoDevice);
+    }
+    return result;
+}
+
+void EventHub::registerVideoDeviceForEpollLocked(const TouchVideoDevice& videoDevice) {
+    status_t result = registerFdForEpoll(videoDevice.getFd());
+    if (result != OK) {
+        ALOGE("Could not add video device %s to epoll", videoDevice.getName().c_str());
+    }
+}
+
+status_t EventHub::unregisterDeviceFromEpollLocked(Device* device) {
+    if (device->hasValidFd()) {
+        status_t result = unregisterFdFromEpoll(device->fd);
+        if (result != OK) {
+            ALOGW("Could not remove input device fd from epoll for device %" PRId32, device->id);
+            return result;
+        }
+    }
+    if (device->videoDevice) {
+        unregisterVideoDeviceFromEpollLocked(*device->videoDevice);
+    }
+    return OK;
+}
+
+void EventHub::unregisterVideoDeviceFromEpollLocked(const TouchVideoDevice& videoDevice) {
+    if (videoDevice.hasValidFd()) {
+        status_t result = unregisterFdFromEpoll(videoDevice.getFd());
+        if (result != OK) {
+            ALOGW("Could not remove video device fd from epoll for device: %s",
+                  videoDevice.getName().c_str());
+        }
+    }
+}
+
+status_t EventHub::openDeviceLocked(const char* devicePath) {
+    char buffer[80];
+
+    ALOGV("Opening device: %s", devicePath);
+
+    int fd = open(devicePath, O_RDWR | O_CLOEXEC | O_NONBLOCK);
+    if (fd < 0) {
+        ALOGE("could not open %s, %s\n", devicePath, strerror(errno));
+        return -1;
+    }
+
+    InputDeviceIdentifier identifier;
+
+    // Get device name.
+    if (ioctl(fd, EVIOCGNAME(sizeof(buffer) - 1), &buffer) < 1) {
+        ALOGE("Could not get device name for %s: %s", devicePath, strerror(errno));
+    } else {
+        buffer[sizeof(buffer) - 1] = '\0';
+        identifier.name = buffer;
+    }
+
+    // Check to see if the device is on our excluded list
+    for (size_t i = 0; i < mExcludedDevices.size(); i++) {
+        const std::string& item = mExcludedDevices[i];
+        if (identifier.name == item) {
+            ALOGI("ignoring event id %s driver %s\n", devicePath, item.c_str());
+            close(fd);
+            return -1;
+        }
+    }
+
+    // Get device driver version.
+    int driverVersion;
+    if (ioctl(fd, EVIOCGVERSION, &driverVersion)) {
+        ALOGE("could not get driver version for %s, %s\n", devicePath, strerror(errno));
+        close(fd);
+        return -1;
+    }
+
+    // Get device identifier.
+    struct input_id inputId;
+    if (ioctl(fd, EVIOCGID, &inputId)) {
+        ALOGE("could not get device input id for %s, %s\n", devicePath, strerror(errno));
+        close(fd);
+        return -1;
+    }
+    identifier.bus = inputId.bustype;
+    identifier.product = inputId.product;
+    identifier.vendor = inputId.vendor;
+    identifier.version = inputId.version;
+
+    // Get device physical location.
+    if (ioctl(fd, EVIOCGPHYS(sizeof(buffer) - 1), &buffer) < 1) {
+        // fprintf(stderr, "could not get location for %s, %s\n", devicePath, strerror(errno));
+    } else {
+        buffer[sizeof(buffer) - 1] = '\0';
+        identifier.location = buffer;
+    }
+
+    // Get device unique id.
+    if (ioctl(fd, EVIOCGUNIQ(sizeof(buffer) - 1), &buffer) < 1) {
+        // fprintf(stderr, "could not get idstring for %s, %s\n", devicePath, strerror(errno));
+    } else {
+        buffer[sizeof(buffer) - 1] = '\0';
+        identifier.uniqueId = buffer;
+    }
+
+    // Fill in the descriptor.
+    assignDescriptorLocked(identifier);
+
+    // Allocate device.  (The device object takes ownership of the fd at this point.)
+    int32_t deviceId = mNextDeviceId++;
+    Device* device = new Device(fd, deviceId, devicePath, identifier);
+
+    ALOGV("add device %d: %s\n", deviceId, devicePath);
+    ALOGV("  bus:        %04x\n"
+          "  vendor      %04x\n"
+          "  product     %04x\n"
+          "  version     %04x\n",
+          identifier.bus, identifier.vendor, identifier.product, identifier.version);
+    ALOGV("  name:       \"%s\"\n", identifier.name.c_str());
+    ALOGV("  location:   \"%s\"\n", identifier.location.c_str());
+    ALOGV("  unique id:  \"%s\"\n", identifier.uniqueId.c_str());
+    ALOGV("  descriptor: \"%s\"\n", identifier.descriptor.c_str());
+    ALOGV("  driver:     v%d.%d.%d\n", driverVersion >> 16, (driverVersion >> 8) & 0xff,
+          driverVersion & 0xff);
+
+    // Load the configuration file for the device.
+    loadConfigurationLocked(device);
+
+    // Figure out the kinds of events the device reports.
+    ioctl(fd, EVIOCGBIT(EV_KEY, sizeof(device->keyBitmask)), device->keyBitmask);
+    ioctl(fd, EVIOCGBIT(EV_ABS, sizeof(device->absBitmask)), device->absBitmask);
+    ioctl(fd, EVIOCGBIT(EV_REL, sizeof(device->relBitmask)), device->relBitmask);
+    ioctl(fd, EVIOCGBIT(EV_SW, sizeof(device->swBitmask)), device->swBitmask);
+    ioctl(fd, EVIOCGBIT(EV_LED, sizeof(device->ledBitmask)), device->ledBitmask);
+    ioctl(fd, EVIOCGBIT(EV_FF, sizeof(device->ffBitmask)), device->ffBitmask);
+    ioctl(fd, EVIOCGPROP(sizeof(device->propBitmask)), device->propBitmask);
+
+    // See if this is a keyboard.  Ignore everything in the button range except for
+    // joystick and gamepad buttons which are handled like keyboards for the most part.
+    bool haveKeyboardKeys =
+            containsNonZeroByte(device->keyBitmask, 0, sizeof_bit_array(BTN_MISC)) ||
+            containsNonZeroByte(device->keyBitmask, sizeof_bit_array(KEY_OK),
+                                sizeof_bit_array(KEY_MAX + 1));
+    bool haveGamepadButtons = containsNonZeroByte(device->keyBitmask, sizeof_bit_array(BTN_MISC),
+                                                  sizeof_bit_array(BTN_MOUSE)) ||
+            containsNonZeroByte(device->keyBitmask, sizeof_bit_array(BTN_JOYSTICK),
+                                sizeof_bit_array(BTN_DIGI));
+    if (haveKeyboardKeys || haveGamepadButtons) {
+        device->classes |= INPUT_DEVICE_CLASS_KEYBOARD;
+    }
+
+    // See if this is a cursor device such as a trackball or mouse.
+    if (test_bit(BTN_MOUSE, device->keyBitmask) && test_bit(REL_X, device->relBitmask) &&
+        test_bit(REL_Y, device->relBitmask)) {
+        device->classes |= INPUT_DEVICE_CLASS_CURSOR;
+    }
+
+    // See if this is a rotary encoder type device.
+    String8 deviceType = String8();
+    if (device->configuration &&
+        device->configuration->tryGetProperty(String8("device.type"), deviceType)) {
+        if (!deviceType.compare(String8("rotaryEncoder"))) {
+            device->classes |= INPUT_DEVICE_CLASS_ROTARY_ENCODER;
+        }
+    }
+
+    // See if this is a touch pad.
+    // Is this a new modern multi-touch driver?
+    if (test_bit(ABS_MT_POSITION_X, device->absBitmask) &&
+        test_bit(ABS_MT_POSITION_Y, device->absBitmask)) {
+        // Some joysticks such as the PS3 controller report axes that conflict
+        // with the ABS_MT range.  Try to confirm that the device really is
+        // a touch screen.
+        if (test_bit(BTN_TOUCH, device->keyBitmask) || !haveGamepadButtons) {
+            device->classes |= INPUT_DEVICE_CLASS_TOUCH | INPUT_DEVICE_CLASS_TOUCH_MT;
+        }
+        // Is this an old style single-touch driver?
+    } else if (test_bit(BTN_TOUCH, device->keyBitmask) && test_bit(ABS_X, device->absBitmask) &&
+               test_bit(ABS_Y, device->absBitmask)) {
+        device->classes |= INPUT_DEVICE_CLASS_TOUCH;
+        // Is this a BT stylus?
+    } else if ((test_bit(ABS_PRESSURE, device->absBitmask) ||
+                test_bit(BTN_TOUCH, device->keyBitmask)) &&
+               !test_bit(ABS_X, device->absBitmask) && !test_bit(ABS_Y, device->absBitmask)) {
+        device->classes |= INPUT_DEVICE_CLASS_EXTERNAL_STYLUS;
+        // Keyboard will try to claim some of the buttons but we really want to reserve those so we
+        // can fuse it with the touch screen data, so just take them back. Note this means an
+        // external stylus cannot also be a keyboard device.
+        device->classes &= ~INPUT_DEVICE_CLASS_KEYBOARD;
+    }
+
+    // See if this device is a joystick.
+    // Assumes that joysticks always have gamepad buttons in order to distinguish them
+    // from other devices such as accelerometers that also have absolute axes.
+    if (haveGamepadButtons) {
+        uint32_t assumedClasses = device->classes | INPUT_DEVICE_CLASS_JOYSTICK;
+        for (int i = 0; i <= ABS_MAX; i++) {
+            if (test_bit(i, device->absBitmask) &&
+                (getAbsAxisUsage(i, assumedClasses) & INPUT_DEVICE_CLASS_JOYSTICK)) {
+                device->classes = assumedClasses;
+                break;
+            }
+        }
+    }
+
+    // Check whether this device has switches.
+    for (int i = 0; i <= SW_MAX; i++) {
+        if (test_bit(i, device->swBitmask)) {
+            device->classes |= INPUT_DEVICE_CLASS_SWITCH;
+            break;
+        }
+    }
+
+    // Check whether this device supports the vibrator.
+    if (test_bit(FF_RUMBLE, device->ffBitmask)) {
+        device->classes |= INPUT_DEVICE_CLASS_VIBRATOR;
+    }
+
+    // Configure virtual keys.
+    if ((device->classes & INPUT_DEVICE_CLASS_TOUCH)) {
+        // Load the virtual keys for the touch screen, if any.
+        // We do this now so that we can make sure to load the keymap if necessary.
+        bool success = loadVirtualKeyMapLocked(device);
+        if (success) {
+            device->classes |= INPUT_DEVICE_CLASS_KEYBOARD;
+        }
+    }
+
+    // Load the key map.
+    // We need to do this for joysticks too because the key layout may specify axes.
+    status_t keyMapStatus = NAME_NOT_FOUND;
+    if (device->classes & (INPUT_DEVICE_CLASS_KEYBOARD | INPUT_DEVICE_CLASS_JOYSTICK)) {
+        // Load the keymap for the device.
+        keyMapStatus = loadKeyMapLocked(device);
+    }
+
+    // Configure the keyboard, gamepad or virtual keyboard.
+    if (device->classes & INPUT_DEVICE_CLASS_KEYBOARD) {
+        // Register the keyboard as a built-in keyboard if it is eligible.
+        if (!keyMapStatus && mBuiltInKeyboardId == NO_BUILT_IN_KEYBOARD &&
+            isEligibleBuiltInKeyboard(device->identifier, device->configuration, &device->keyMap)) {
+            mBuiltInKeyboardId = device->id;
+        }
+
+        // 'Q' key support = cheap test of whether this is an alpha-capable kbd
+        if (hasKeycodeLocked(device, AKEYCODE_Q)) {
+            device->classes |= INPUT_DEVICE_CLASS_ALPHAKEY;
+        }
+
+        // See if this device has a DPAD.
+        if (hasKeycodeLocked(device, AKEYCODE_DPAD_UP) &&
+            hasKeycodeLocked(device, AKEYCODE_DPAD_DOWN) &&
+            hasKeycodeLocked(device, AKEYCODE_DPAD_LEFT) &&
+            hasKeycodeLocked(device, AKEYCODE_DPAD_RIGHT) &&
+            hasKeycodeLocked(device, AKEYCODE_DPAD_CENTER)) {
+            device->classes |= INPUT_DEVICE_CLASS_DPAD;
+        }
+
+        // See if this device has a gamepad.
+        for (size_t i = 0; i < sizeof(GAMEPAD_KEYCODES) / sizeof(GAMEPAD_KEYCODES[0]); i++) {
+            if (hasKeycodeLocked(device, GAMEPAD_KEYCODES[i])) {
+                device->classes |= INPUT_DEVICE_CLASS_GAMEPAD;
+                break;
+            }
+        }
+    }
+
+    // If the device isn't recognized as something we handle, don't monitor it.
+    if (device->classes == 0) {
+        ALOGV("Dropping device: id=%d, path='%s', name='%s'", deviceId, devicePath,
+              device->identifier.name.c_str());
+        delete device;
+        return -1;
+    }
+
+    // Determine whether the device has a mic.
+    if (deviceHasMicLocked(device)) {
+        device->classes |= INPUT_DEVICE_CLASS_MIC;
+    }
+
+    // Determine whether the device is external or internal.
+    if (isExternalDeviceLocked(device)) {
+        device->classes |= INPUT_DEVICE_CLASS_EXTERNAL;
+    }
+
+    if (device->classes & (INPUT_DEVICE_CLASS_JOYSTICK | INPUT_DEVICE_CLASS_DPAD) &&
+        device->classes & INPUT_DEVICE_CLASS_GAMEPAD) {
+        device->controllerNumber = getNextControllerNumberLocked(device);
+        setLedForControllerLocked(device);
+    }
+
+    // Find a matching video device by comparing device names
+    // This should be done before registerDeviceForEpollLocked, so that both fds are added to epoll
+    for (std::unique_ptr<TouchVideoDevice>& videoDevice : mUnattachedVideoDevices) {
+        if (device->identifier.name == videoDevice->getName()) {
+            device->videoDevice = std::move(videoDevice);
+            break;
+        }
+    }
+    mUnattachedVideoDevices
+            .erase(std::remove_if(mUnattachedVideoDevices.begin(), mUnattachedVideoDevices.end(),
+                                  [](const std::unique_ptr<TouchVideoDevice>& videoDevice) {
+                                      return videoDevice == nullptr;
+                                  }),
+                   mUnattachedVideoDevices.end());
+
+    if (registerDeviceForEpollLocked(device) != OK) {
+        delete device;
+        return -1;
+    }
+
+    configureFd(device);
+
+    ALOGI("New device: id=%d, fd=%d, path='%s', name='%s', classes=0x%x, "
+          "configuration='%s', keyLayout='%s', keyCharacterMap='%s', builtinKeyboard=%s, ",
+          deviceId, fd, devicePath, device->identifier.name.c_str(), device->classes,
+          device->configurationFile.c_str(), device->keyMap.keyLayoutFile.c_str(),
+          device->keyMap.keyCharacterMapFile.c_str(), toString(mBuiltInKeyboardId == deviceId));
+
+    addDeviceLocked(device);
+    return OK;
+}
+
+void EventHub::configureFd(Device* device) {
+    // Set fd parameters with ioctl, such as key repeat, suspend block, and clock type
+    if (device->classes & INPUT_DEVICE_CLASS_KEYBOARD) {
+        // Disable kernel key repeat since we handle it ourselves
+        unsigned int repeatRate[] = {0, 0};
+        if (ioctl(device->fd, EVIOCSREP, repeatRate)) {
+            ALOGW("Unable to disable kernel key repeat for %s: %s", device->path.c_str(),
+                  strerror(errno));
+        }
+    }
+
+    // Tell the kernel that we want to use the monotonic clock for reporting timestamps
+    // associated with input events.  This is important because the input system
+    // uses the timestamps extensively and assumes they were recorded using the monotonic
+    // clock.
+    int clockId = CLOCK_MONOTONIC;
+    bool usingClockIoctl = !ioctl(device->fd, EVIOCSCLOCKID, &clockId);
+    ALOGI("usingClockIoctl=%s", toString(usingClockIoctl));
+}
+
+void EventHub::openVideoDeviceLocked(const std::string& devicePath) {
+    std::unique_ptr<TouchVideoDevice> videoDevice = TouchVideoDevice::create(devicePath);
+    if (!videoDevice) {
+        ALOGE("Could not create touch video device for %s. Ignoring", devicePath.c_str());
+        return;
+    }
+    // Transfer ownership of this video device to a matching input device
+    for (size_t i = 0; i < mDevices.size(); i++) {
+        Device* device = mDevices.valueAt(i);
+        if (videoDevice->getName() == device->identifier.name) {
+            device->videoDevice = std::move(videoDevice);
+            if (device->enabled) {
+                registerVideoDeviceForEpollLocked(*device->videoDevice);
+            }
+            return;
+        }
+    }
+
+    // Couldn't find a matching input device, so just add it to a temporary holding queue.
+    // A matching input device may appear later.
+    ALOGI("Adding video device %s to list of unattached video devices",
+          videoDevice->getName().c_str());
+    mUnattachedVideoDevices.push_back(std::move(videoDevice));
+}
+
+bool EventHub::isDeviceEnabled(int32_t deviceId) {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device == nullptr) {
+        ALOGE("Invalid device id=%" PRId32 " provided to %s", deviceId, __func__);
+        return false;
+    }
+    return device->enabled;
+}
+
+status_t EventHub::enableDevice(int32_t deviceId) {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device == nullptr) {
+        ALOGE("Invalid device id=%" PRId32 " provided to %s", deviceId, __func__);
+        return BAD_VALUE;
+    }
+    if (device->enabled) {
+        ALOGW("Duplicate call to %s, input device %" PRId32 " already enabled", __func__, deviceId);
+        return OK;
+    }
+    status_t result = device->enable();
+    if (result != OK) {
+        ALOGE("Failed to enable device %" PRId32, deviceId);
+        return result;
+    }
+
+    configureFd(device);
+
+    return registerDeviceForEpollLocked(device);
+}
+
+status_t EventHub::disableDevice(int32_t deviceId) {
+    AutoMutex _l(mLock);
+    Device* device = getDeviceLocked(deviceId);
+    if (device == nullptr) {
+        ALOGE("Invalid device id=%" PRId32 " provided to %s", deviceId, __func__);
+        return BAD_VALUE;
+    }
+    if (!device->enabled) {
+        ALOGW("Duplicate call to %s, input device already disabled", __func__);
+        return OK;
+    }
+    unregisterDeviceFromEpollLocked(device);
+    return device->disable();
+}
+
+void EventHub::createVirtualKeyboardLocked() {
+    InputDeviceIdentifier identifier;
+    identifier.name = "Virtual";
+    identifier.uniqueId = "<virtual>";
+    assignDescriptorLocked(identifier);
+
+    Device* device =
+            new Device(-1, ReservedInputDeviceId::VIRTUAL_KEYBOARD_ID, "<virtual>", identifier);
+    device->classes = INPUT_DEVICE_CLASS_KEYBOARD | INPUT_DEVICE_CLASS_ALPHAKEY |
+            INPUT_DEVICE_CLASS_DPAD | INPUT_DEVICE_CLASS_VIRTUAL;
+    loadKeyMapLocked(device);
+    addDeviceLocked(device);
+}
+
+void EventHub::addDeviceLocked(Device* device) {
+    mDevices.add(device->id, device);
+    device->next = mOpeningDevices;
+    mOpeningDevices = device;
+}
+
+void EventHub::loadConfigurationLocked(Device* device) {
+    device->configurationFile = getInputDeviceConfigurationFilePathByDeviceIdentifier(
+            device->identifier, INPUT_DEVICE_CONFIGURATION_FILE_TYPE_CONFIGURATION);
+    if (device->configurationFile.empty()) {
+        ALOGD("No input device configuration file found for device '%s'.",
+              device->identifier.name.c_str());
+    } else {
+        status_t status = PropertyMap::load(String8(device->configurationFile.c_str()),
+                                            &device->configuration);
+        if (status) {
+            ALOGE("Error loading input device configuration file for device '%s'.  "
+                  "Using default configuration.",
+                  device->identifier.name.c_str());
+        }
+    }
+}
+
+bool EventHub::loadVirtualKeyMapLocked(Device* device) {
+    // The virtual key map is supplied by the kernel as a system board property file.
+    std::string path;
+    path += "/sys/board_properties/virtualkeys.";
+    path += device->identifier.getCanonicalName();
+    if (access(path.c_str(), R_OK)) {
+        return false;
+    }
+    device->virtualKeyMap = VirtualKeyMap::load(path);
+    return device->virtualKeyMap != nullptr;
+}
+
+status_t EventHub::loadKeyMapLocked(Device* device) {
+    return device->keyMap.load(device->identifier, device->configuration);
+}
+
+bool EventHub::isExternalDeviceLocked(Device* device) {
+    if (device->configuration) {
+        bool value;
+        if (device->configuration->tryGetProperty(String8("device.internal"), value)) {
+            return !value;
+        }
+    }
+    return device->identifier.bus == BUS_USB || device->identifier.bus == BUS_BLUETOOTH;
+}
+
+bool EventHub::deviceHasMicLocked(Device* device) {
+    if (device->configuration) {
+        bool value;
+        if (device->configuration->tryGetProperty(String8("audio.mic"), value)) {
+            return value;
+        }
+    }
+    return false;
+}
+
+int32_t EventHub::getNextControllerNumberLocked(Device* device) {
+    if (mControllerNumbers.isFull()) {
+        ALOGI("Maximum number of controllers reached, assigning controller number 0 to device %s",
+              device->identifier.name.c_str());
+        return 0;
+    }
+    // Since the controller number 0 is reserved for non-controllers, translate all numbers up by
+    // one
+    return static_cast<int32_t>(mControllerNumbers.markFirstUnmarkedBit() + 1);
+}
+
+void EventHub::releaseControllerNumberLocked(Device* device) {
+    int32_t num = device->controllerNumber;
+    device->controllerNumber = 0;
+    if (num == 0) {
+        return;
+    }
+    mControllerNumbers.clearBit(static_cast<uint32_t>(num - 1));
+}
+
+void EventHub::setLedForControllerLocked(Device* device) {
+    for (int i = 0; i < MAX_CONTROLLER_LEDS; i++) {
+        setLedStateLocked(device, ALED_CONTROLLER_1 + i, device->controllerNumber == i + 1);
+    }
+}
+
+bool EventHub::hasKeycodeLocked(Device* device, int keycode) const {
+    if (!device->keyMap.haveKeyLayout()) {
+        return false;
+    }
+
+    std::vector<int32_t> scanCodes;
+    device->keyMap.keyLayoutMap->findScanCodesForKey(keycode, &scanCodes);
+    const size_t N = scanCodes.size();
+    for (size_t i = 0; i < N && i <= KEY_MAX; i++) {
+        int32_t sc = scanCodes[i];
+        if (sc >= 0 && sc <= KEY_MAX && test_bit(sc, device->keyBitmask)) {
+            return true;
+        }
+    }
+
+    return false;
+}
+
+status_t EventHub::mapLed(Device* device, int32_t led, int32_t* outScanCode) const {
+    if (!device->keyMap.haveKeyLayout()) {
+        return NAME_NOT_FOUND;
+    }
+
+    int32_t scanCode;
+    if (device->keyMap.keyLayoutMap->findScanCodeForLed(led, &scanCode) != NAME_NOT_FOUND) {
+        if (scanCode >= 0 && scanCode <= LED_MAX && test_bit(scanCode, device->ledBitmask)) {
+            *outScanCode = scanCode;
+            return NO_ERROR;
+        }
+    }
+    return NAME_NOT_FOUND;
+}
+
+void EventHub::closeDeviceByPathLocked(const char* devicePath) {
+    Device* device = getDeviceByPathLocked(devicePath);
+    if (device) {
+        closeDeviceLocked(device);
+        return;
+    }
+    ALOGV("Remove device: %s not found, device may already have been removed.", devicePath);
+}
+
+/**
+ * Find the video device by filename, and close it.
+ * The video device is closed by path during an inotify event, where we don't have the
+ * additional context about the video device fd, or the associated input device.
+ */
+void EventHub::closeVideoDeviceByPathLocked(const std::string& devicePath) {
+    // A video device may be owned by an existing input device, or it may be stored in
+    // the mUnattachedVideoDevices queue. Check both locations.
+    for (size_t i = 0; i < mDevices.size(); i++) {
+        Device* device = mDevices.valueAt(i);
+        if (device->videoDevice && device->videoDevice->getPath() == devicePath) {
+            unregisterVideoDeviceFromEpollLocked(*device->videoDevice);
+            device->videoDevice = nullptr;
+            return;
+        }
+    }
+    mUnattachedVideoDevices
+            .erase(std::remove_if(mUnattachedVideoDevices.begin(), mUnattachedVideoDevices.end(),
+                                  [&devicePath](
+                                          const std::unique_ptr<TouchVideoDevice>& videoDevice) {
+                                      return videoDevice->getPath() == devicePath;
+                                  }),
+                   mUnattachedVideoDevices.end());
+}
+
+void EventHub::closeAllDevicesLocked() {
+    mUnattachedVideoDevices.clear();
+    while (mDevices.size() > 0) {
+        closeDeviceLocked(mDevices.valueAt(mDevices.size() - 1));
+    }
+}
+
+void EventHub::closeDeviceLocked(Device* device) {
+    ALOGI("Removed device: path=%s name=%s id=%d fd=%d classes=0x%x", device->path.c_str(),
+          device->identifier.name.c_str(), device->id, device->fd, device->classes);
+
+    if (device->id == mBuiltInKeyboardId) {
+        ALOGW("built-in keyboard device %s (id=%d) is closing! the apps will not like this",
+              device->path.c_str(), mBuiltInKeyboardId);
+        mBuiltInKeyboardId = NO_BUILT_IN_KEYBOARD;
+    }
+
+    unregisterDeviceFromEpollLocked(device);
+    if (device->videoDevice) {
+        // This must be done after the video device is removed from epoll
+        mUnattachedVideoDevices.push_back(std::move(device->videoDevice));
+    }
+
+    releaseControllerNumberLocked(device);
+
+    mDevices.removeItem(device->id);
+    device->close();
+
+    // Unlink for opening devices list if it is present.
+    Device* pred = nullptr;
+    bool found = false;
+    for (Device* entry = mOpeningDevices; entry != nullptr;) {
+        if (entry == device) {
+            found = true;
+            break;
+        }
+        pred = entry;
+        entry = entry->next;
+    }
+    if (found) {
+        // Unlink the device from the opening devices list then delete it.
+        // We don't need to tell the client that the device was closed because
+        // it does not even know it was opened in the first place.
+        ALOGI("Device %s was immediately closed after opening.", device->path.c_str());
+        if (pred) {
+            pred->next = device->next;
+        } else {
+            mOpeningDevices = device->next;
+        }
+        delete device;
+    } else {
+        // Link into closing devices list.
+        // The device will be deleted later after we have informed the client.
+        device->next = mClosingDevices;
+        mClosingDevices = device;
+    }
+}
+
+status_t EventHub::readNotifyLocked() {
+    int res;
+    char event_buf[512];
+    int event_size;
+    int event_pos = 0;
+    struct inotify_event* event;
+
+    ALOGV("EventHub::readNotify nfd: %d\n", mINotifyFd);
+    res = read(mINotifyFd, event_buf, sizeof(event_buf));
+    if (res < (int)sizeof(*event)) {
+        if (errno == EINTR) return 0;
+        ALOGW("could not get event, %s\n", strerror(errno));
+        return -1;
+    }
+
+    while (res >= (int)sizeof(*event)) {
+        event = (struct inotify_event*)(event_buf + event_pos);
+        if (event->len) {
+            if (event->wd == mInputWd) {
+                std::string filename = StringPrintf("%s/%s", DEVICE_PATH, event->name);
+                if (event->mask & IN_CREATE) {
+                    openDeviceLocked(filename.c_str());
+                } else {
+                    ALOGI("Removing device '%s' due to inotify event\n", filename.c_str());
+                    closeDeviceByPathLocked(filename.c_str());
+                }
+            } else if (event->wd == mVideoWd) {
+                if (isV4lTouchNode(event->name)) {
+                    std::string filename = StringPrintf("%s/%s", VIDEO_DEVICE_PATH, event->name);
+                    if (event->mask & IN_CREATE) {
+                        openVideoDeviceLocked(filename);
+                    } else {
+                        ALOGI("Removing video device '%s' due to inotify event", filename.c_str());
+                        closeVideoDeviceByPathLocked(filename);
+                    }
+                }
+            } else {
+                LOG_ALWAYS_FATAL("Unexpected inotify event, wd = %i", event->wd);
+            }
+        }
+        event_size = sizeof(*event) + event->len;
+        res -= event_size;
+        event_pos += event_size;
+    }
+    return 0;
+}
+
+status_t EventHub::scanDirLocked(const char* dirname) {
+    char devname[PATH_MAX];
+    char* filename;
+    DIR* dir;
+    struct dirent* de;
+    dir = opendir(dirname);
+    if (dir == nullptr) return -1;
+    strcpy(devname, dirname);
+    filename = devname + strlen(devname);
+    *filename++ = '/';
+    while ((de = readdir(dir))) {
+        if (de->d_name[0] == '.' &&
+            (de->d_name[1] == '\0' || (de->d_name[1] == '.' && de->d_name[2] == '\0')))
+            continue;
+        strcpy(filename, de->d_name);
+        openDeviceLocked(devname);
+    }
+    closedir(dir);
+    return 0;
+}
+
+/**
+ * Look for all dirname/v4l-touch* devices, and open them.
+ */
+status_t EventHub::scanVideoDirLocked(const std::string& dirname) {
+    DIR* dir;
+    struct dirent* de;
+    dir = opendir(dirname.c_str());
+    if (!dir) {
+        ALOGE("Could not open video directory %s", dirname.c_str());
+        return BAD_VALUE;
+    }
+
+    while ((de = readdir(dir))) {
+        const char* name = de->d_name;
+        if (isV4lTouchNode(name)) {
+            ALOGI("Found touch video device %s", name);
+            openVideoDeviceLocked(dirname + "/" + name);
+        }
+    }
+    closedir(dir);
+    return OK;
+}
+
+void EventHub::requestReopenDevices() {
+    ALOGV("requestReopenDevices() called");
+
+    AutoMutex _l(mLock);
+    mNeedToReopenDevices = true;
+}
+
+void EventHub::dump(std::string& dump) {
+    dump += "Event Hub State:\n";
+
+    { // acquire lock
+        AutoMutex _l(mLock);
+
+        dump += StringPrintf(INDENT "BuiltInKeyboardId: %d\n", mBuiltInKeyboardId);
+
+        dump += INDENT "Devices:\n";
+
+        for (size_t i = 0; i < mDevices.size(); i++) {
+            const Device* device = mDevices.valueAt(i);
+            if (mBuiltInKeyboardId == device->id) {
+                dump += StringPrintf(INDENT2 "%d: %s (aka device 0 - built-in keyboard)\n",
+                                     device->id, device->identifier.name.c_str());
+            } else {
+                dump += StringPrintf(INDENT2 "%d: %s\n", device->id,
+                                     device->identifier.name.c_str());
+            }
+            dump += StringPrintf(INDENT3 "Classes: 0x%08x\n", device->classes);
+            dump += StringPrintf(INDENT3 "Path: %s\n", device->path.c_str());
+            dump += StringPrintf(INDENT3 "Enabled: %s\n", toString(device->enabled));
+            dump += StringPrintf(INDENT3 "Descriptor: %s\n", device->identifier.descriptor.c_str());
+            dump += StringPrintf(INDENT3 "Location: %s\n", device->identifier.location.c_str());
+            dump += StringPrintf(INDENT3 "ControllerNumber: %d\n", device->controllerNumber);
+            dump += StringPrintf(INDENT3 "UniqueId: %s\n", device->identifier.uniqueId.c_str());
+            dump += StringPrintf(INDENT3 "Identifier: bus=0x%04x, vendor=0x%04x, "
+                                         "product=0x%04x, version=0x%04x\n",
+                                 device->identifier.bus, device->identifier.vendor,
+                                 device->identifier.product, device->identifier.version);
+            dump += StringPrintf(INDENT3 "KeyLayoutFile: %s\n",
+                                 device->keyMap.keyLayoutFile.c_str());
+            dump += StringPrintf(INDENT3 "KeyCharacterMapFile: %s\n",
+                                 device->keyMap.keyCharacterMapFile.c_str());
+            dump += StringPrintf(INDENT3 "ConfigurationFile: %s\n",
+                                 device->configurationFile.c_str());
+            dump += StringPrintf(INDENT3 "HaveKeyboardLayoutOverlay: %s\n",
+                                 toString(device->overlayKeyMap != nullptr));
+            dump += INDENT3 "VideoDevice: ";
+            if (device->videoDevice) {
+                dump += device->videoDevice->dump() + "\n";
+            } else {
+                dump += "<none>\n";
+            }
+        }
+
+        dump += INDENT "Unattached video devices:\n";
+        for (const std::unique_ptr<TouchVideoDevice>& videoDevice : mUnattachedVideoDevices) {
+            dump += INDENT2 + videoDevice->dump() + "\n";
+        }
+        if (mUnattachedVideoDevices.empty()) {
+            dump += INDENT2 "<none>\n";
+        }
+    } // release lock
+}
+
+void EventHub::monitor() {
+    // Acquire and release the lock to ensure that the event hub has not deadlocked.
+    mLock.lock();
+    mLock.unlock();
+}
+
+}; // namespace android