Merge changes I086b5045,I753fb07a,Iea2bb7fd

* changes:
  Improve EventHub const-correctness
  Refactor AssociatedDevice initialization in EventHub
  EventHub: Associate AsociatedDevice using sysfs path, not descriptor

5 files changed, 188 insertions, 179 deletions

diff --git a/include/input/KeyLayoutMap.h b/include/input/KeyLayoutMap.h
index 1da78aa0c1..a6c696df26 100644
--- a/include/input/KeyLayoutMap.h
+++ b/include/input/KeyLayoutMap.h
@@ -78,7 +78,7 @@ public:
     std::optional<AxisInfo> mapAxis(int32_t scanCode) const;
     const std::string getLoadFileName() const;
     // Return pair of sensor type and sensor data index, for the input device abs code
-    base::Result<std::pair<InputDeviceSensorType, int32_t>> mapSensor(int32_t absCode);
+    base::Result<std::pair<InputDeviceSensorType, int32_t>> mapSensor(int32_t absCode) const;
 
     virtual ~KeyLayoutMap();
 
diff --git a/libs/input/KeyLayoutMap.cpp b/libs/input/KeyLayoutMap.cpp
index d6b4579a94..73710330d0 100644
--- a/libs/input/KeyLayoutMap.cpp
+++ b/libs/input/KeyLayoutMap.cpp
@@ -192,7 +192,8 @@ status_t KeyLayoutMap::mapKey(int32_t scanCode, int32_t usageCode,
 }
 
 // Return pair of sensor type and sensor data index, for the input device abs code
-base::Result<std::pair<InputDeviceSensorType, int32_t>> KeyLayoutMap::mapSensor(int32_t absCode) {
+base::Result<std::pair<InputDeviceSensorType, int32_t>> KeyLayoutMap::mapSensor(
+        int32_t absCode) const {
     auto it = mSensorsByAbsCode.find(absCode);
     if (it == mSensorsByAbsCode.end()) {
         ALOGD_IF(DEBUG_MAPPING, "mapSensor: absCode=%d, ~ Failed.", absCode);
diff --git a/services/inputflinger/reader/EventHub.cpp b/services/inputflinger/reader/EventHub.cpp
index bfa44acd17..06a38c8f0f 100644
--- a/services/inputflinger/reader/EventHub.cpp
+++ b/services/inputflinger/reader/EventHub.cpp
@@ -52,6 +52,7 @@
 
 #include <filesystem>
 #include <regex>
+#include <utility>
 
 #include "EventHub.h"
 
@@ -193,8 +194,7 @@ static nsecs_t processEventTimestamp(const struct input_event& event) {
 }
 
 /**
- * Returns the sysfs root path of the input device
- *
+ * Returns the sysfs root path of the input device.
  */
 static std::optional<std::filesystem::path> getSysfsRootPath(const char* devicePath) {
     std::error_code errorCode;
@@ -301,6 +301,83 @@ static std::optional<std::array<LightColor, COLOR_NUM>> getColorIndexArray(
     return colors;
 }
 
+/**
+ * Read information about batteries exposed through the sysfs path.
+ */
+static std::unordered_map<int32_t /*batteryId*/, RawBatteryInfo> readBatteryConfiguration(
+        const std::filesystem::path& sysfsRootPath) {
+    std::unordered_map<int32_t, RawBatteryInfo> batteryInfos;
+    int32_t nextBatteryId = 0;
+    // Check if device has any battery.
+    const auto& paths = findSysfsNodes(sysfsRootPath, SysfsClass::POWER_SUPPLY);
+    for (const auto& nodePath : paths) {
+        RawBatteryInfo info;
+        info.id = ++nextBatteryId;
+        info.path = nodePath;
+        info.name = nodePath.filename();
+
+        // Scan the path for all the files
+        // Refer to https://www.kernel.org/doc/Documentation/leds/leds-class.txt
+        const auto& files = allFilesInPath(nodePath);
+        for (const auto& file : files) {
+            const auto it = BATTERY_CLASSES.find(file.filename().string());
+            if (it != BATTERY_CLASSES.end()) {
+                info.flags |= it->second;
+            }
+        }
+        batteryInfos.insert_or_assign(info.id, info);
+        ALOGD("configureBatteryLocked rawBatteryId %d name %s", info.id, info.name.c_str());
+    }
+    return batteryInfos;
+}
+
+/**
+ *  Read information about lights exposed through the sysfs path.
+ */
+static std::unordered_map<int32_t /*lightId*/, RawLightInfo> readLightsConfiguration(
+        const std::filesystem::path& sysfsRootPath) {
+    std::unordered_map<int32_t, RawLightInfo> lightInfos;
+    int32_t nextLightId = 0;
+    // Check if device has any lights.
+    const auto& paths = findSysfsNodes(sysfsRootPath, SysfsClass::LEDS);
+    for (const auto& nodePath : paths) {
+        RawLightInfo info;
+        info.id = ++nextLightId;
+        info.path = nodePath;
+        info.name = nodePath.filename();
+        info.maxBrightness = std::nullopt;
+        size_t nameStart = info.name.rfind(":");
+        if (nameStart != std::string::npos) {
+            // Trim the name to color name
+            info.name = info.name.substr(nameStart + 1);
+            // Set InputLightClass flag for colors
+            const auto it = LIGHT_CLASSES.find(info.name);
+            if (it != LIGHT_CLASSES.end()) {
+                info.flags |= it->second;
+            }
+        }
+        // Scan the path for all the files
+        // Refer to https://www.kernel.org/doc/Documentation/leds/leds-class.txt
+        const auto& files = allFilesInPath(nodePath);
+        for (const auto& file : files) {
+            const auto it = LIGHT_CLASSES.find(file.filename().string());
+            if (it != LIGHT_CLASSES.end()) {
+                info.flags |= it->second;
+                // If the node has maximum brightness, read it
+                if (it->second == InputLightClass::MAX_BRIGHTNESS) {
+                    std::string str;
+                    if (base::ReadFileToString(file, &str)) {
+                        info.maxBrightness = std::stoi(str);
+                    }
+                }
+            }
+        }
+        lightInfos.insert_or_assign(info.id, info);
+        ALOGD("configureLightsLocked rawLightId %d name %s", info.id, info.name.c_str());
+    }
+    return lightInfos;
+}
+
 // --- Global Functions ---
 
 ftl::Flags<InputDeviceClass> getAbsAxisUsage(int32_t axis,
@@ -357,18 +434,18 @@ ftl::Flags<InputDeviceClass> getAbsAxisUsage(int32_t axis,
 
 // --- EventHub::Device ---
 
-EventHub::Device::Device(int fd, int32_t id, const std::string& path,
-                         const InputDeviceIdentifier& identifier)
+EventHub::Device::Device(int fd, int32_t id, std::string path, InputDeviceIdentifier identifier,
+                         std::shared_ptr<const AssociatedDevice> assocDev)
       : fd(fd),
         id(id),
-        path(path),
-        identifier(identifier),
+        path(std::move(path)),
+        identifier(std::move(identifier)),
         classes(0),
         configuration(nullptr),
         virtualKeyMap(nullptr),
         ffEffectPlaying(false),
         ffEffectId(-1),
-        associatedDevice(nullptr),
+        associatedDevice(std::move(assocDev)),
         controllerNumber(0),
         enabled(true),
         isVirtual(fd < 0) {}
@@ -557,75 +634,6 @@ status_t EventHub::Device::mapLed(int32_t led, int32_t* outScanCode) const {
     return NAME_NOT_FOUND;
 }
 
-// Check the sysfs path for any input device batteries, returns true if battery found.
-bool EventHub::AssociatedDevice::configureBatteryLocked() {
-    nextBatteryId = 0;
-    // Check if device has any battery.
-    const auto& paths = findSysfsNodes(sysfsRootPath, SysfsClass::POWER_SUPPLY);
-    for (const auto& nodePath : paths) {
-        RawBatteryInfo info;
-        info.id = ++nextBatteryId;
-        info.path = nodePath;
-        info.name = nodePath.filename();
-
-        // Scan the path for all the files
-        // Refer to https://www.kernel.org/doc/Documentation/leds/leds-class.txt
-        const auto& files = allFilesInPath(nodePath);
-        for (const auto& file : files) {
-            const auto it = BATTERY_CLASSES.find(file.filename().string());
-            if (it != BATTERY_CLASSES.end()) {
-                info.flags |= it->second;
-            }
-        }
-        batteryInfos.insert_or_assign(info.id, info);
-        ALOGD("configureBatteryLocked rawBatteryId %d name %s", info.id, info.name.c_str());
-    }
-    return !batteryInfos.empty();
-}
-
-// Check the sysfs path for any input device lights, returns true if lights found.
-bool EventHub::AssociatedDevice::configureLightsLocked() {
-    nextLightId = 0;
-    // Check if device has any lights.
-    const auto& paths = findSysfsNodes(sysfsRootPath, SysfsClass::LEDS);
-    for (const auto& nodePath : paths) {
-        RawLightInfo info;
-        info.id = ++nextLightId;
-        info.path = nodePath;
-        info.name = nodePath.filename();
-        info.maxBrightness = std::nullopt;
-        size_t nameStart = info.name.rfind(":");
-        if (nameStart != std::string::npos) {
-            // Trim the name to color name
-            info.name = info.name.substr(nameStart + 1);
-            // Set InputLightClass flag for colors
-            const auto it = LIGHT_CLASSES.find(info.name);
-            if (it != LIGHT_CLASSES.end()) {
-                info.flags |= it->second;
-            }
-        }
-        // Scan the path for all the files
-        // Refer to https://www.kernel.org/doc/Documentation/leds/leds-class.txt
-        const auto& files = allFilesInPath(nodePath);
-        for (const auto& file : files) {
-            const auto it = LIGHT_CLASSES.find(file.filename().string());
-            if (it != LIGHT_CLASSES.end()) {
-                info.flags |= it->second;
-                // If the node has maximum brightness, read it
-                if (it->second == InputLightClass::MAX_BRIGHTNESS) {
-                    std::string str;
-                    if (base::ReadFileToString(file, &str)) {
-                        info.maxBrightness = std::stoi(str);
-                    }
-                }
-            }
-        }
-        lightInfos.insert_or_assign(info.id, info);
-        ALOGD("configureLightsLocked rawLightId %d name %s", info.id, info.name.c_str());
-    }
-    return !lightInfos.empty();
-}
-
 /**
  * Get the capabilities for the current process.
  * Crashes the system if unable to create / check / destroy the capabilities object.
@@ -1034,7 +1042,7 @@ status_t EventHub::mapAxis(int32_t deviceId, int32_t scanCode, AxisInfo* outAxis
 }
 
 base::Result<std::pair<InputDeviceSensorType, int32_t>> EventHub::mapSensor(int32_t deviceId,
-                                                                            int32_t absCode) {
+                                                                            int32_t absCode) const {
     std::scoped_lock _l(mLock);
     Device* device = getDeviceLocked(deviceId);
 
@@ -1056,18 +1064,19 @@ const std::unordered_map<int32_t, RawBatteryInfo>& EventHub::getBatteryInfoLocke
     return device->associatedDevice->batteryInfos;
 }
 
-const std::vector<int32_t> EventHub::getRawBatteryIds(int32_t deviceId) {
+std::vector<int32_t> EventHub::getRawBatteryIds(int32_t deviceId) const {
     std::scoped_lock _l(mLock);
     std::vector<int32_t> batteryIds;
 
-    for (const auto [id, info] : getBatteryInfoLocked(deviceId)) {
+    for (const auto& [id, info] : getBatteryInfoLocked(deviceId)) {
         batteryIds.push_back(id);
     }
 
     return batteryIds;
 }
 
-std::optional<RawBatteryInfo> EventHub::getRawBatteryInfo(int32_t deviceId, int32_t batteryId) {
+std::optional<RawBatteryInfo> EventHub::getRawBatteryInfo(int32_t deviceId,
+                                                          int32_t batteryId) const {
     std::scoped_lock _l(mLock);
 
     const auto infos = getBatteryInfoLocked(deviceId);
@@ -1081,7 +1090,7 @@ std::optional<RawBatteryInfo> EventHub::getRawBatteryInfo(int32_t deviceId, int3
 }
 
 // Gets the light info map from light ID to RawLightInfo of the miscellaneous device associated
-// with the deivice ID. Returns an empty map if no miscellaneous device found.
+// with the device ID. Returns an empty map if no miscellaneous device found.
 const std::unordered_map<int32_t, RawLightInfo>& EventHub::getLightInfoLocked(
         int32_t deviceId) const {
     static const std::unordered_map<int32_t, RawLightInfo> EMPTY_LIGHT_INFO = {};
@@ -1092,18 +1101,18 @@ const std::unordered_map<int32_t, RawLightInfo>& EventHub::getLightInfoLocked(
     return device->associatedDevice->lightInfos;
 }
 
-const std::vector<int32_t> EventHub::getRawLightIds(int32_t deviceId) {
+std::vector<int32_t> EventHub::getRawLightIds(int32_t deviceId) const {
     std::scoped_lock _l(mLock);
     std::vector<int32_t> lightIds;
 
-    for (const auto [id, info] : getLightInfoLocked(deviceId)) {
+    for (const auto& [id, info] : getLightInfoLocked(deviceId)) {
         lightIds.push_back(id);
     }
 
     return lightIds;
 }
 
-std::optional<RawLightInfo> EventHub::getRawLightInfo(int32_t deviceId, int32_t lightId) {
+std::optional<RawLightInfo> EventHub::getRawLightInfo(int32_t deviceId, int32_t lightId) const {
     std::scoped_lock _l(mLock);
 
     const auto infos = getLightInfoLocked(deviceId);
@@ -1116,7 +1125,7 @@ std::optional<RawLightInfo> EventHub::getRawLightInfo(int32_t deviceId, int32_t
     return std::nullopt;
 }
 
-std::optional<int32_t> EventHub::getLightBrightness(int32_t deviceId, int32_t lightId) {
+std::optional<int32_t> EventHub::getLightBrightness(int32_t deviceId, int32_t lightId) const {
     std::scoped_lock _l(mLock);
 
     const auto infos = getLightInfoLocked(deviceId);
@@ -1133,7 +1142,7 @@ std::optional<int32_t> EventHub::getLightBrightness(int32_t deviceId, int32_t li
 }
 
 std::optional<std::unordered_map<LightColor, int32_t>> EventHub::getLightIntensities(
-        int32_t deviceId, int32_t lightId) {
+        int32_t deviceId, int32_t lightId) const {
     std::scoped_lock _l(mLock);
 
     const auto infos = getLightInfoLocked(deviceId);
@@ -1358,6 +1367,27 @@ void EventHub::assignDescriptorLocked(InputDeviceIdentifier& identifier) {
           identifier.descriptor.c_str());
 }
 
+std::shared_ptr<const EventHub::AssociatedDevice> EventHub::obtainAssociatedDeviceLocked(
+        const std::filesystem::path& devicePath) const {
+    const std::optional<std::filesystem::path> sysfsRootPathOpt =
+            getSysfsRootPath(devicePath.c_str());
+    if (!sysfsRootPathOpt) {
+        return nullptr;
+    }
+
+    const auto& path = *sysfsRootPathOpt;
+    for (const auto& [id, dev] : mDevices) {
+        if (dev->associatedDevice && dev->associatedDevice->sysfsRootPath == path) {
+            return dev->associatedDevice;
+        }
+    }
+
+    return std::make_shared<AssociatedDevice>(
+            AssociatedDevice{.sysfsRootPath = path,
+                             .batteryInfos = readBatteryConfiguration(path),
+                             .lightInfos = readLightsConfiguration(path)});
+}
+
 void EventHub::vibrate(int32_t deviceId, const VibrationElement& element) {
     std::scoped_lock _l(mLock);
     Device* device = getDeviceLocked(deviceId);
@@ -1415,7 +1445,7 @@ void EventHub::cancelVibrate(int32_t deviceId) {
     }
 }
 
-std::vector<int32_t> EventHub::getVibratorIds(int32_t deviceId) {
+std::vector<int32_t> EventHub::getVibratorIds(int32_t deviceId) const {
     std::scoped_lock _l(mLock);
     std::vector<int32_t> vibrators;
     Device* device = getDeviceLocked(deviceId);
@@ -2024,7 +2054,9 @@ void EventHub::openDeviceLocked(const std::string& devicePath) {
 
     // Allocate device.  (The device object takes ownership of the fd at this point.)
     int32_t deviceId = mNextDeviceId++;
-    std::unique_ptr<Device> device = std::make_unique<Device>(fd, deviceId, devicePath, identifier);
+    std::unique_ptr<Device> device =
+            std::make_unique<Device>(fd, deviceId, devicePath, identifier,
+                                     obtainAssociatedDeviceLocked(devicePath));
 
     ALOGV("add device %d: %s\n", deviceId, devicePath.c_str());
     ALOGV("  bus:        %04x\n"
@@ -2042,27 +2074,6 @@ void EventHub::openDeviceLocked(const std::string& devicePath) {
     // Load the configuration file for the device.
     device->loadConfigurationLocked();
 
-    bool hasBattery = false;
-    bool hasLights = false;
-    // Check the sysfs root path
-    std::optional<std::filesystem::path> sysfsRootPath = getSysfsRootPath(devicePath.c_str());
-    if (sysfsRootPath.has_value()) {
-        std::shared_ptr<AssociatedDevice> associatedDevice;
-        for (const auto& [id, dev] : mDevices) {
-            if (device->identifier.descriptor == dev->identifier.descriptor &&
-                !dev->associatedDevice) {
-                associatedDevice = dev->associatedDevice;
-            }
-        }
-        if (!associatedDevice) {
-            associatedDevice = std::make_shared<AssociatedDevice>(sysfsRootPath.value());
-        }
-        hasBattery = associatedDevice->configureBatteryLocked();
-        hasLights = associatedDevice->configureLightsLocked();
-
-        device->associatedDevice = associatedDevice;
-    }
-
     // Figure out the kinds of events the device reports.
     device->readDeviceBitMask(EVIOCGBIT(EV_KEY, 0), device->keyBitmask);
     device->readDeviceBitMask(EVIOCGBIT(EV_ABS, 0), device->absBitmask);
@@ -2212,12 +2223,12 @@ void EventHub::openDeviceLocked(const std::string& devicePath) {
     }
 
     // Classify InputDeviceClass::BATTERY.
-    if (hasBattery) {
+    if (device->associatedDevice && !device->associatedDevice->batteryInfos.empty()) {
         device->classes |= InputDeviceClass::BATTERY;
     }
 
     // Classify InputDeviceClass::LIGHT.
-    if (hasLights) {
+    if (device->associatedDevice && !device->associatedDevice->lightInfos.empty()) {
         device->classes |= InputDeviceClass::LIGHT;
     }
 
@@ -2285,7 +2296,7 @@ bool EventHub::tryAddVideoDeviceLocked(EventHub::Device& device,
     return true;
 }
 
-bool EventHub::isDeviceEnabled(int32_t deviceId) {
+bool EventHub::isDeviceEnabled(int32_t deviceId) const {
     std::scoped_lock _l(mLock);
     Device* device = getDeviceLocked(deviceId);
     if (device == nullptr) {
@@ -2340,7 +2351,7 @@ void EventHub::createVirtualKeyboardLocked() {
 
     std::unique_ptr<Device> device =
             std::make_unique<Device>(-1, ReservedInputDeviceId::VIRTUAL_KEYBOARD_ID, "<virtual>",
-                                     identifier);
+                                     identifier, nullptr /*associatedDevice*/);
     device->classes = InputDeviceClass::KEYBOARD | InputDeviceClass::ALPHAKEY |
             InputDeviceClass::DPAD | InputDeviceClass::VIRTUAL;
     device->loadKeyMapLocked();
@@ -2509,7 +2520,7 @@ void EventHub::requestReopenDevices() {
     mNeedToReopenDevices = true;
 }
 
-void EventHub::dump(std::string& dump) {
+void EventHub::dump(std::string& dump) const {
     dump += "Event Hub State:\n";
 
     { // acquire lock
@@ -2544,12 +2555,13 @@ void EventHub::dump(std::string& dump) {
                                  device->keyMap.keyCharacterMapFile.c_str());
             dump += StringPrintf(INDENT3 "ConfigurationFile: %s\n",
                                  device->configurationFile.c_str());
-            dump += INDENT3 "VideoDevice: ";
-            if (device->videoDevice) {
-                dump += device->videoDevice->dump() + "\n";
-            } else {
-                dump += "<none>\n";
-            }
+            dump += StringPrintf(INDENT3 "VideoDevice: %s\n",
+                                 device->videoDevice ? device->videoDevice->dump().c_str()
+                                                     : "<none>");
+            dump += StringPrintf(INDENT3 "SysfsDevicePath: %s\n",
+                                 device->associatedDevice
+                                         ? device->associatedDevice->sysfsRootPath.c_str()
+                                         : "<none>");
         }
 
         dump += INDENT "Unattached video devices:\n";
@@ -2562,9 +2574,9 @@ void EventHub::dump(std::string& dump) {
     } // release lock
 }
 
-void EventHub::monitor() {
+void EventHub::monitor() const {
     // Acquire and release the lock to ensure that the event hub has not deadlocked.
     std::unique_lock<std::mutex> lock(mLock);
 }
 
-}; // namespace android
+} // namespace android
diff --git a/services/inputflinger/reader/include/EventHub.h b/services/inputflinger/reader/include/EventHub.h
index 4733ecb323..8aec367795 100644
--- a/services/inputflinger/reader/include/EventHub.h
+++ b/services/inputflinger/reader/include/EventHub.h
@@ -21,6 +21,7 @@
 #include <climits>
 #include <filesystem>
 #include <unordered_map>
+#include <utility>
 #include <vector>
 
 #include <batteryservice/BatteryService.h>
@@ -281,22 +282,23 @@ public:
      */
     virtual size_t getEvents(int timeoutMillis, RawEvent* buffer, size_t bufferSize) = 0;
     virtual std::vector<TouchVideoFrame> getVideoFrames(int32_t deviceId) = 0;
-    virtual base::Result<std::pair<InputDeviceSensorType, int32_t>> mapSensor(int32_t deviceId,
-                                                                              int32_t absCode) = 0;
+    virtual base::Result<std::pair<InputDeviceSensorType, int32_t>> mapSensor(
+            int32_t deviceId, int32_t absCode) const = 0;
     // Raw batteries are sysfs power_supply nodes we found from the EventHub device sysfs node,
     // containing the raw info of the sysfs node structure.
-    virtual const std::vector<int32_t> getRawBatteryIds(int32_t deviceId) = 0;
+    virtual std::vector<int32_t> getRawBatteryIds(int32_t deviceId) const = 0;
     virtual std::optional<RawBatteryInfo> getRawBatteryInfo(int32_t deviceId,
-                                                            int32_t BatteryId) = 0;
+                                                            int32_t BatteryId) const = 0;
 
     // Raw lights are sysfs led light nodes we found from the EventHub device sysfs node,
     // containing the raw info of the sysfs node structure.
-    virtual const std::vector<int32_t> getRawLightIds(int32_t deviceId) = 0;
-    virtual std::optional<RawLightInfo> getRawLightInfo(int32_t deviceId, int32_t lightId) = 0;
-    virtual std::optional<int32_t> getLightBrightness(int32_t deviceId, int32_t lightId) = 0;
+    virtual std::vector<int32_t> getRawLightIds(int32_t deviceId) const = 0;
+    virtual std::optional<RawLightInfo> getRawLightInfo(int32_t deviceId,
+                                                        int32_t lightId) const = 0;
+    virtual std::optional<int32_t> getLightBrightness(int32_t deviceId, int32_t lightId) const = 0;
     virtual void setLightBrightness(int32_t deviceId, int32_t lightId, int32_t brightness) = 0;
     virtual std::optional<std::unordered_map<LightColor, int32_t>> getLightIntensities(
-            int32_t deviceId, int32_t lightId) = 0;
+            int32_t deviceId, int32_t lightId) const = 0;
     virtual void setLightIntensities(int32_t deviceId, int32_t lightId,
                                      std::unordered_map<LightColor, int32_t> intensities) = 0;
     /*
@@ -332,7 +334,7 @@ public:
     /* Control the vibrator. */
     virtual void vibrate(int32_t deviceId, const VibrationElement& effect) = 0;
     virtual void cancelVibrate(int32_t deviceId) = 0;
-    virtual std::vector<int32_t> getVibratorIds(int32_t deviceId) = 0;
+    virtual std::vector<int32_t> getVibratorIds(int32_t deviceId) const = 0;
 
     /* Query battery level. */
     virtual std::optional<int32_t> getBatteryCapacity(int32_t deviceId,
@@ -348,13 +350,13 @@ public:
     virtual void wake() = 0;
 
     /* Dump EventHub state to a string. */
-    virtual void dump(std::string& dump) = 0;
+    virtual void dump(std::string& dump) const = 0;
 
     /* Called by the heatbeat to ensures that the reader has not deadlocked. */
-    virtual void monitor() = 0;
+    virtual void monitor() const = 0;
 
     /* Return true if the device is enabled. */
-    virtual bool isDeviceEnabled(int32_t deviceId) = 0;
+    virtual bool isDeviceEnabled(int32_t deviceId) const = 0;
 
     /* Enable an input device */
     virtual status_t enableDevice(int32_t deviceId) = 0;
@@ -462,20 +464,22 @@ public:
                      AxisInfo* outAxisInfo) const override final;
 
     base::Result<std::pair<InputDeviceSensorType, int32_t>> mapSensor(
-            int32_t deviceId, int32_t absCode) override final;
+            int32_t deviceId, int32_t absCode) const override final;
 
-    const std::vector<int32_t> getRawBatteryIds(int32_t deviceId) override final;
+    std::vector<int32_t> getRawBatteryIds(int32_t deviceId) const override final;
     std::optional<RawBatteryInfo> getRawBatteryInfo(int32_t deviceId,
-                                                    int32_t BatteryId) override final;
+                                                    int32_t BatteryId) const override final;
 
-    const std::vector<int32_t> getRawLightIds(int32_t deviceId) override final;
+    std::vector<int32_t> getRawLightIds(int32_t deviceId) const override final;
 
-    std::optional<RawLightInfo> getRawLightInfo(int32_t deviceId, int32_t lightId) override final;
+    std::optional<RawLightInfo> getRawLightInfo(int32_t deviceId,
+                                                int32_t lightId) const override final;
 
-    std::optional<int32_t> getLightBrightness(int32_t deviceId, int32_t lightId) override final;
+    std::optional<int32_t> getLightBrightness(int32_t deviceId,
+                                              int32_t lightId) const override final;
     void setLightBrightness(int32_t deviceId, int32_t lightId, int32_t brightness) override final;
     std::optional<std::unordered_map<LightColor, int32_t>> getLightIntensities(
-            int32_t deviceId, int32_t lightId) override final;
+            int32_t deviceId, int32_t lightId) const override final;
     void setLightIntensities(int32_t deviceId, int32_t lightId,
                              std::unordered_map<LightColor, int32_t> intensities) override final;
 
@@ -511,15 +515,15 @@ public:
 
     void vibrate(int32_t deviceId, const VibrationElement& effect) override final;
     void cancelVibrate(int32_t deviceId) override final;
-    std::vector<int32_t> getVibratorIds(int32_t deviceId) override final;
+    std::vector<int32_t> getVibratorIds(int32_t deviceId) const override final;
 
     void requestReopenDevices() override final;
 
     void wake() override final;
 
-    void dump(std::string& dump) override final;
+    void dump(std::string& dump) const override final;
 
-    void monitor() override final;
+    void monitor() const override final;
 
     std::optional<int32_t> getBatteryCapacity(int32_t deviceId,
                                               int32_t batteryId) const override final;
@@ -527,7 +531,7 @@ public:
     std::optional<int32_t> getBatteryStatus(int32_t deviceId,
                                             int32_t batteryId) const override final;
 
-    bool isDeviceEnabled(int32_t deviceId) override final;
+    bool isDeviceEnabled(int32_t deviceId) const override final;
 
     status_t enableDevice(int32_t deviceId) override final;
 
@@ -536,20 +540,13 @@ public:
     ~EventHub() override;
 
 private:
+    // Holds information about the sysfs device associated with the Device.
     struct AssociatedDevice {
-        // The device descriptor from evdev device the misc device associated with.
-        std::string descriptor;
         // The sysfs root path of the misc device.
         std::filesystem::path sysfsRootPath;
 
-        int32_t nextBatteryId;
-        int32_t nextLightId;
-        std::unordered_map<int32_t, RawBatteryInfo> batteryInfos;
-        std::unordered_map<int32_t, RawLightInfo> lightInfos;
-        explicit AssociatedDevice(std::filesystem::path sysfsRootPath)
-              : sysfsRootPath(sysfsRootPath), nextBatteryId(0), nextLightId(0) {}
-        bool configureBatteryLocked();
-        bool configureLightsLocked();
+        std::unordered_map<int32_t /*batteryId*/, RawBatteryInfo> batteryInfos;
+        std::unordered_map<int32_t /*lightId*/, RawLightInfo> lightInfos;
     };
 
     struct Device {
@@ -582,13 +579,13 @@ private:
         int16_t ffEffectId; // initially -1
 
         // A shared_ptr of a device associated with the input device.
-        // The input devices with same descriptor has the same associated device.
-        std::shared_ptr<AssociatedDevice> associatedDevice;
+        // The input devices that have the same sysfs path have the same associated device.
+        const std::shared_ptr<const AssociatedDevice> associatedDevice;
 
         int32_t controllerNumber;
 
-        Device(int fd, int32_t id, const std::string& path,
-               const InputDeviceIdentifier& identifier);
+        Device(int fd, int32_t id, std::string path, InputDeviceIdentifier identifier,
+               std::shared_ptr<const AssociatedDevice> assocDev);
         ~Device();
 
         void close();
@@ -633,6 +630,8 @@ private:
     void createVirtualKeyboardLocked() REQUIRES(mLock);
     void addDeviceLocked(std::unique_ptr<Device> device) REQUIRES(mLock);
     void assignDescriptorLocked(InputDeviceIdentifier& identifier) REQUIRES(mLock);
+    std::shared_ptr<const AssociatedDevice> obtainAssociatedDeviceLocked(
+            const std::filesystem::path& devicePath) const REQUIRES(mLock);
 
     void closeDeviceByPathLocked(const std::string& devicePath) REQUIRES(mLock);
     void closeVideoDeviceByPathLocked(const std::string& devicePath) REQUIRES(mLock);
diff --git a/services/inputflinger/tests/InputReader_test.cpp b/services/inputflinger/tests/InputReader_test.cpp
index 24721de75b..9a0c565de3 100644
--- a/services/inputflinger/tests/InputReader_test.cpp
+++ b/services/inputflinger/tests/InputReader_test.cpp
@@ -509,7 +509,7 @@ public:
         enqueueEvent(ARBITRARY_TIME, READ_TIME, deviceId, EventHubInterface::DEVICE_REMOVED, 0, 0);
     }
 
-    bool isDeviceEnabled(int32_t deviceId) {
+    bool isDeviceEnabled(int32_t deviceId) const override {
         Device* device = getDevice(deviceId);
         if (device == nullptr) {
             ALOGE("Incorrect device id=%" PRId32 " provided to %s", deviceId, __func__);
@@ -518,7 +518,7 @@ public:
         return device->enabled;
     }
 
-    status_t enableDevice(int32_t deviceId) {
+    status_t enableDevice(int32_t deviceId) override {
         status_t result;
         Device* device = getDevice(deviceId);
         if (device == nullptr) {
@@ -533,7 +533,7 @@ public:
         return result;
     }
 
-    status_t disableDevice(int32_t deviceId) {
+    status_t disableDevice(int32_t deviceId) override {
         Device* device = getDevice(deviceId);
         if (device == nullptr) {
             ALOGE("Incorrect device id=%" PRId32 " provided to %s", deviceId, __func__);
@@ -795,8 +795,8 @@ private:
 
     status_t mapAxis(int32_t, int32_t, AxisInfo*) const override { return NAME_NOT_FOUND; }
 
-    base::Result<std::pair<InputDeviceSensorType, int32_t>> mapSensor(int32_t deviceId,
-                                                                      int32_t absCode) {
+    base::Result<std::pair<InputDeviceSensorType, int32_t>> mapSensor(
+            int32_t deviceId, int32_t absCode) const override {
         Device* device = getDevice(deviceId);
         if (!device) {
             return Errorf("Sensor device not found.");
@@ -981,7 +981,7 @@ private:
 
     void cancelVibrate(int32_t) override {}
 
-    std::vector<int32_t> getVibratorIds(int32_t deviceId) override { return mVibrators; };
+    std::vector<int32_t> getVibratorIds(int32_t deviceId) const override { return mVibrators; };
 
     std::optional<int32_t> getBatteryCapacity(int32_t, int32_t) const override {
         return BATTERY_CAPACITY;
@@ -991,13 +991,14 @@ private:
         return BATTERY_STATUS;
     }
 
-    const std::vector<int32_t> getRawBatteryIds(int32_t deviceId) { return {}; }
+    std::vector<int32_t> getRawBatteryIds(int32_t deviceId) const override { return {}; }
 
-    std::optional<RawBatteryInfo> getRawBatteryInfo(int32_t deviceId, int32_t batteryId) {
+    std::optional<RawBatteryInfo> getRawBatteryInfo(int32_t deviceId,
+                                                    int32_t batteryId) const override {
         return std::nullopt;
     }
 
-    const std::vector<int32_t> getRawLightIds(int32_t deviceId) override {
+    std::vector<int32_t> getRawLightIds(int32_t deviceId) const override {
         std::vector<int32_t> ids;
         for (const auto& [rawId, info] : mRawLightInfos) {
             ids.push_back(rawId);
@@ -1005,7 +1006,7 @@ private:
         return ids;
     }
 
-    std::optional<RawLightInfo> getRawLightInfo(int32_t deviceId, int32_t lightId) override {
+    std::optional<RawLightInfo> getRawLightInfo(int32_t deviceId, int32_t lightId) const override {
         auto it = mRawLightInfos.find(lightId);
         if (it == mRawLightInfos.end()) {
             return std::nullopt;
@@ -1022,7 +1023,7 @@ private:
         mLightIntensities.emplace(lightId, intensities);
     };
 
-    std::optional<int32_t> getLightBrightness(int32_t deviceId, int32_t lightId) override {
+    std::optional<int32_t> getLightBrightness(int32_t deviceId, int32_t lightId) const override {
         auto lightIt = mLightBrightness.find(lightId);
         if (lightIt == mLightBrightness.end()) {
             return std::nullopt;
@@ -1031,7 +1032,7 @@ private:
     }
 
     std::optional<std::unordered_map<LightColor, int32_t>> getLightIntensities(
-            int32_t deviceId, int32_t lightId) override {
+            int32_t deviceId, int32_t lightId) const override {
         auto lightIt = mLightIntensities.find(lightId);
         if (lightIt == mLightIntensities.end()) {
             return std::nullopt;
@@ -1039,13 +1040,9 @@ private:
         return lightIt->second;
     };
 
-    virtual bool isExternal(int32_t) const {
-        return false;
-    }
-
-    void dump(std::string&) override {}
+    void dump(std::string&) const override {}
 
-    void monitor() override {}
+    void monitor() const override {}
 
     void requestReopenDevices() override {}