diff --git a/camera/Android.bp b/camera/Android.bp
index fb6de9e..c6a76fb 100644
--- a/camera/Android.bp
+++ b/camera/Android.bp
@@ -7,4 +7,5 @@
     "device/3.2/default",
     "metadata/3.2",
     "provider/2.4",
+    "provider/2.4/default",
 ]
diff --git a/camera/common/1.0/default/CameraModule.cpp b/camera/common/1.0/default/CameraModule.cpp
index d8a424e..5d9ae4d 100644
--- a/camera/common/1.0/default/CameraModule.cpp
+++ b/camera/common/1.0/default/CameraModule.cpp
@@ -344,7 +344,7 @@
     return res;
 }
 
-bool CameraModule::isOpenLegacyDefined() {
+bool CameraModule::isOpenLegacyDefined() const {
     if (getModuleApiVersion() < CAMERA_MODULE_API_VERSION_2_3) {
         return false;
     }
@@ -376,7 +376,7 @@
     return res;
 }
 
-bool CameraModule::isVendorTagDefined() {
+bool CameraModule::isVendorTagDefined() const {
     return mModule->get_vendor_tag_ops != NULL;
 }
 
@@ -388,11 +388,25 @@
     }
 }
 
+bool CameraModule::isSetTorchModeSupported() const {
+    if (getModuleApiVersion() >= CAMERA_MODULE_API_VERSION_2_4) {
+        if (mModule->set_torch_mode == NULL) {
+            ALOGE("%s: Module 2.4 device must support set torch API!",
+                    __FUNCTION__);
+            return false;
+        }
+        return true;
+    }
+    return false;
+}
+
 int CameraModule::setTorchMode(const char* camera_id, bool enable) {
-    int res;
-    ATRACE_BEGIN("camera_module->set_torch_mode");
-    res = mModule->set_torch_mode(camera_id, enable);
-    ATRACE_END();
+    int res = INVALID_OPERATION;
+    if (mModule->set_torch_mode != NULL) {
+        ATRACE_BEGIN("camera_module->set_torch_mode");
+        res = mModule->set_torch_mode(camera_id, enable);
+        ATRACE_END();
+    }
     return res;
 }
 
@@ -409,19 +423,19 @@
     return -ENODEV;
 }
 
-uint16_t CameraModule::getModuleApiVersion() {
+uint16_t CameraModule::getModuleApiVersion() const {
     return mModule->common.module_api_version;
 }
 
-const char* CameraModule::getModuleName() {
+const char* CameraModule::getModuleName() const {
     return mModule->common.name;
 }
 
-uint16_t CameraModule::getHalApiVersion() {
+uint16_t CameraModule::getHalApiVersion() const {
     return mModule->common.hal_api_version;
 }
 
-const char* CameraModule::getModuleAuthor() {
+const char* CameraModule::getModuleAuthor() const {
     return mModule->common.author;
 }
 
diff --git a/camera/common/1.0/default/include/CameraModule.h b/camera/common/1.0/default/include/CameraModule.h
index 907c807..68d4f90 100644
--- a/camera/common/1.0/default/include/CameraModule.h
+++ b/camera/common/1.0/default/include/CameraModule.h
@@ -49,16 +49,17 @@
     int getDeviceVersion(int cameraId);
     int getNumberOfCameras(void);
     int open(const char* id, struct hw_device_t** device);
-    bool isOpenLegacyDefined();
+    bool isOpenLegacyDefined() const;
     int openLegacy(const char* id, uint32_t halVersion, struct hw_device_t** device);
     int setCallbacks(const camera_module_callbacks_t *callbacks);
-    bool isVendorTagDefined();
+    bool isVendorTagDefined() const;
     void getVendorTagOps(vendor_tag_ops_t* ops);
+    bool isSetTorchModeSupported() const;
     int setTorchMode(const char* camera_id, bool enable);
-    uint16_t getModuleApiVersion();
-    const char* getModuleName();
-    uint16_t getHalApiVersion();
-    const char* getModuleAuthor();
+    uint16_t getModuleApiVersion() const;
+    const char* getModuleName() const;
+    uint16_t getHalApiVersion() const;
+    const char* getModuleAuthor() const;
     // Only used by CameraModuleFixture native test. Do NOT use elsewhere.
     void *getDso();
 
diff --git a/camera/device/1.0/ICameraDevice.hal b/camera/device/1.0/ICameraDevice.hal
index acca9a7..d232a67 100644
--- a/camera/device/1.0/ICameraDevice.hal
+++ b/camera/device/1.0/ICameraDevice.hal
@@ -78,11 +78,6 @@
      */
     getCameraInfo() generates (Status status, CameraInfo info);
 
-    // TODO: add query setTorch mode support so camera service can tell whether
-    //       it needs to simulate torch or not (without calling setTorchMode
-    //       which is visible to end user)
-    //       Should this be put to device hal or provider hal?
-
     /**
      * setTorchMode:
      *
diff --git a/camera/provider/2.4/ICameraProvider.hal b/camera/provider/2.4/ICameraProvider.hal
index 564167b..3015b7d 100644
--- a/camera/provider/2.4/ICameraProvider.hal
+++ b/camera/provider/2.4/ICameraProvider.hal
@@ -120,6 +120,30 @@
             generates (Status status, vec<string> cameraDeviceNames);
 
     /**
+     * isSetTorchModeSupported:
+     *
+     * Returns if the camera devices known to this camera provider support
+     * setTorchMode API or not. If the provider does not support setTorchMode
+     * API, calling to setTorchMode will return METHOD_NOT_SUPPORTED.
+     *
+     * Note that not every camera device has a flash unit, so even this API
+     * returns true, setTorchMode call might still fail due to the camera device
+     * does not have a flash unit. In such case, the returned status will be
+     * OPERATION_NOT_SUPPORTED.
+     *
+     * @return status Status code for the operation, one of:
+     *     OK:
+     *         On a succesful call
+     *     INTERNAL_ERROR:
+     *         Torch API support cannot be queried. This may be due to
+     *         a failure to initialize the camera subsystem, for example.
+     * @return support Whether the camera devices known to this provider
+     *     supports setTorchMode API or not.
+     *
+     */
+    isSetTorchModeSupported() generates (Status status, bool support);
+
+    /**
      * getCameraDeviceInterface_VN_x:
      *
      * Return a android.hardware.camera.device@N.x/ICameraDevice interface for
diff --git a/camera/provider/2.4/default/Android.bp b/camera/provider/2.4/default/Android.bp
new file mode 100644
index 0000000..f28c9cd
--- /dev/null
+++ b/camera/provider/2.4/default/Android.bp
@@ -0,0 +1,23 @@
+cc_library_shared {
+    name: "android.hardware.camera.provider@2.4-impl",
+    relative_install_path: "hw",
+    srcs: ["CameraProvider.cpp"],
+    shared_libs: [
+        "libhidlbase",
+        "libhidltransport",
+        "libhwbinder",
+        "libutils",
+        "libcutils",
+        "android.hardware.camera.device@1.0",
+        "android.hardware.camera.device@3.2",
+        "android.hardware.camera.device@3.2-impl",
+        "android.hardware.camera.provider@2.4",
+        "android.hardware.camera.common@1.0",
+        "liblog",
+        "libhardware",
+        "libcamera_metadata"
+    ],
+    static_libs: [
+        "android.hardware.camera.common@1.0-helper"
+    ]
+}
diff --git a/camera/provider/2.4/default/CameraProvider.cpp b/camera/provider/2.4/default/CameraProvider.cpp
new file mode 100644
index 0000000..d9ac261
--- /dev/null
+++ b/camera/provider/2.4/default/CameraProvider.cpp
@@ -0,0 +1,405 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#define LOG_TAG "CamProvider@2.4-impl"
+#include <android/log.h>
+
+#include <regex>
+
+#include "CameraProvider.h"
+#include "CameraDevice.h"
+#include <string.h>
+#include <utils/Trace.h>
+
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace provider {
+namespace V2_4 {
+namespace implementation {
+
+namespace {
+const char *kLegacyProviderName = "legacy/0";
+// "device@<version>/legacy/<id>"
+const std::regex kDeviceNameRE("device@([0-9]+\\.[0-9]+)/legacy/(.+)");
+const char *kHAL3_2 = "3.2";
+const char *kHAL1_0 = "1.0";
+const int kMaxCameraDeviceNameLen = 128;
+const int kMaxCameraIdLen = 16;
+
+} // anonymous namespace
+
+using ::android::hardware::camera::common::V1_0::CameraMetadataType;
+using ::android::hardware::camera::common::V1_0::Status;
+
+/**
+ * static callback forwarding methods from HAL to instance
+ */
+void CameraProvider::sCameraDeviceStatusChange(
+        const struct camera_module_callbacks* callbacks,
+        int camera_id,
+        int new_status) {
+    ALOGI("%s++", __FUNCTION__);
+    sp<CameraProvider> cp = const_cast<CameraProvider*>(
+            static_cast<const CameraProvider*>(callbacks));
+
+    if (cp == nullptr) {
+        ALOGE("%s: callback ops is null", __FUNCTION__);
+        return;
+    }
+
+    ALOGI("%s resolved provider %p", __FUNCTION__, cp.get());
+
+    Mutex::Autolock _l(cp->mCbLock);
+    char cameraId[kMaxCameraIdLen];
+    snprintf(cameraId, sizeof(cameraId), "%d", camera_id);
+    std::string cameraIdStr(cameraId);
+    cp->mCameraStatusMap[cameraIdStr] = (camera_device_status_t) new_status;
+    if (cp->mCallbacks != nullptr) {
+        CameraDeviceStatus status = (CameraDeviceStatus) new_status;
+        for (auto const& deviceNamePair : cp->mCameraDeviceNames) {
+            if (cameraIdStr.compare(deviceNamePair.first) == 0) {
+                cp->mCallbacks->cameraDeviceStatusChange(
+                        deviceNamePair.second, status);
+            }
+        }
+    }
+    ALOGI("%s--", __FUNCTION__);
+}
+
+void CameraProvider::sTorchModeStatusChange(
+        const struct camera_module_callbacks* callbacks,
+        const char* camera_id,
+        int new_status) {
+    ALOGI("%s++", __FUNCTION__);
+    sp<CameraProvider> cp = const_cast<CameraProvider*>(
+            static_cast<const CameraProvider*>(callbacks));
+
+    if (cp == nullptr) {
+        ALOGE("%s: callback ops is null", __FUNCTION__);
+        return;
+    }
+
+    ALOGI("%s resolved provider %p", __FUNCTION__, cp.get());
+
+    Mutex::Autolock _l(cp->mCbLock);
+    if (cp->mCallbacks != nullptr) {
+        std::string cameraIdStr(camera_id);
+        TorchModeStatus status = (TorchModeStatus) new_status;
+        for (auto const& deviceNamePair : cp->mCameraDeviceNames) {
+            if (cameraIdStr.compare(getLegacyCameraId(deviceNamePair.first)) == 0) {
+                cp->mCallbacks->torchModeStatusChange(
+                        deviceNamePair.second, status);
+            }
+        }
+    }
+    ALOGI("%s--", __FUNCTION__);
+}
+
+Status CameraProvider::getHidlStatus(int status) {
+    switch (status) {
+        case 0: return Status::OK;
+        case -ENODEV: return Status::INTERNAL_ERROR;
+        case -EINVAL: return Status::ILLEGAL_ARGUMENT;
+        default:
+            ALOGE("%s: unknown HAL status code %d", __FUNCTION__, status);
+            return Status::INTERNAL_ERROR;
+    }
+}
+
+bool CameraProvider::matchDeviceName(const hidl_string& deviceName, std::smatch& sm) {
+    std::string deviceNameStd(deviceName.c_str());
+    return std::regex_match(deviceNameStd, sm, kDeviceNameRE);
+}
+
+std::string CameraProvider::getLegacyCameraId(const hidl_string& deviceName) {
+    std::smatch sm;
+    bool match = matchDeviceName(deviceName, sm);
+    if (!match) {
+        return std::string("");
+    }
+    return sm[2];
+}
+
+int CameraProvider::getCameraDeviceVersion(const hidl_string& deviceName) {
+    std::smatch sm;
+    bool match = matchDeviceName(deviceName, sm);
+    if (!match) {
+        return -1;
+    }
+    if (sm[1].compare(kHAL3_2) == 0) {
+        // maybe switched to 3.4 or define the hidl version enumlater
+        return CAMERA_DEVICE_API_VERSION_3_2;
+    } else if (sm[1].compare(kHAL1_0) == 0) {
+        return CAMERA_DEVICE_API_VERSION_1_0;
+    }
+    return 0;
+}
+
+std::string CameraProvider::getHidlDeviceName(
+        std::string cameraId, int deviceVersion) {
+    // Maybe consider create a version check method and SortedVec to speed up?
+    if (deviceVersion != CAMERA_DEVICE_API_VERSION_1_0 &&
+            deviceVersion != CAMERA_DEVICE_API_VERSION_3_2 &&
+            deviceVersion != CAMERA_DEVICE_API_VERSION_3_3 &&
+            deviceVersion != CAMERA_DEVICE_API_VERSION_3_4 ) {
+        return hidl_string("");
+    }
+    const char* versionStr = (deviceVersion == CAMERA_DEVICE_API_VERSION_1_0) ? kHAL1_0 : kHAL3_2;
+    char deviceName[kMaxCameraDeviceNameLen];
+    snprintf(deviceName, sizeof(deviceName), "device@%s/legacy/%s",
+            versionStr, cameraId.c_str());
+    return deviceName;
+}
+
+CameraProvider::CameraProvider() :
+        camera_module_callbacks_t({sCameraDeviceStatusChange,
+                                   sTorchModeStatusChange}) {
+    mInitFailed = initialize();
+}
+
+CameraProvider::~CameraProvider() {}
+
+bool CameraProvider::initialize() {
+    camera_module_t *rawModule;
+    int err = hw_get_module(CAMERA_HARDWARE_MODULE_ID,
+            (const hw_module_t **)&rawModule);
+    if (err < 0) {
+        ALOGE("Could not load camera HAL module: %d (%s)", err, strerror(-err));
+        return true;
+    }
+
+    mModule = new CameraModule(rawModule);
+    err = mModule->init();
+    if (err != OK) {
+        ALOGE("Could not initialize camera HAL module: %d (%s)", err,
+            strerror(-err));
+        mModule.clear();
+        return true;
+    }
+    ALOGI("Loaded \"%s\" camera module", mModule->getModuleName());
+
+    mNumberOfLegacyCameras = mModule->getNumberOfCameras();
+    for (int i = 0; i < mNumberOfLegacyCameras; i++) {
+        char cameraId[kMaxCameraIdLen];
+        snprintf(cameraId, sizeof(cameraId), "%d", i);
+        std::string cameraIdStr(cameraId);
+        mCameraStatusMap[cameraIdStr] = CAMERA_DEVICE_STATUS_PRESENT;
+        mCameraIds.add(cameraIdStr);
+
+        // initialize mCameraDeviceNames and mOpenLegacySupported
+        mOpenLegacySupported[cameraIdStr] = false;
+        int deviceVersion = mModule->getDeviceVersion(i);
+        mCameraDeviceNames.add(
+                std::make_pair(cameraIdStr,
+                               getHidlDeviceName(cameraIdStr, deviceVersion)));
+        if (deviceVersion >= CAMERA_DEVICE_API_VERSION_3_2 &&
+                mModule->isOpenLegacyDefined()) {
+            // try open_legacy to see if it actually works
+            struct hw_device_t* halDev = nullptr;
+            int ret = mModule->openLegacy(cameraId, CAMERA_DEVICE_API_VERSION_1_0, &halDev);
+            if (ret == 0) {
+                mOpenLegacySupported[cameraIdStr] = true;
+                halDev->close(halDev);
+                mCameraDeviceNames.add(
+                        std::make_pair(cameraIdStr,
+                                getHidlDeviceName(cameraIdStr, CAMERA_DEVICE_API_VERSION_1_0)));
+            } else if (ret == -EBUSY || ret == -EUSERS) {
+                // Looks like this provider instance is not initialized during
+                // system startup and there are other camera users already.
+                // Not a good sign but not fatal.
+                ALOGW("%s: open_legacy try failed!", __FUNCTION__);
+            }
+        }
+    }
+
+    // Setup vendor tags here so HAL can setup vendor keys in camera characteristics
+    VendorTagDescriptor::clearGlobalVendorTagDescriptor();
+    setUpVendorTags();
+    return false;
+}
+
+bool CameraProvider::setUpVendorTags() {
+    ATRACE_CALL();
+    vendor_tag_ops_t vOps = vendor_tag_ops_t();
+
+    // Check if vendor operations have been implemented
+    if (!mModule->isVendorTagDefined()) {
+        ALOGI("%s: No vendor tags defined for this device.", __FUNCTION__);
+        return false;
+    }
+
+    mModule->getVendorTagOps(&vOps);
+
+    // Ensure all vendor operations are present
+    if (vOps.get_tag_count == nullptr || vOps.get_all_tags == nullptr ||
+            vOps.get_section_name == nullptr || vOps.get_tag_name == nullptr ||
+            vOps.get_tag_type == nullptr) {
+        ALOGE("%s: Vendor tag operations not fully defined. Ignoring definitions."
+               , __FUNCTION__);
+        return false;
+    }
+
+    // Read all vendor tag definitions into a descriptor
+    sp<VendorTagDescriptor> desc;
+    status_t res;
+    if ((res = VendorTagDescriptor::createDescriptorFromOps(&vOps, /*out*/desc))
+            != OK) {
+        ALOGE("%s: Could not generate descriptor from vendor tag operations,"
+              "received error %s (%d). Camera clients will not be able to use"
+              "vendor tags", __FUNCTION__, strerror(res), res);
+        return false;
+    }
+
+    // Set the global descriptor to use with camera metadata
+    VendorTagDescriptor::setAsGlobalVendorTagDescriptor(desc);
+    const SortedVector<String8>* sectionNames = desc->getAllSectionNames();
+    size_t numSections = sectionNames->size();
+    std::vector<std::vector<VendorTag>> tagsBySection(numSections);
+    int tagCount = desc->getTagCount();
+    std::vector<uint32_t> tags(tagCount);
+    desc->getTagArray(tags.data());
+    for (int i = 0; i < tagCount; i++) {
+        VendorTag vt;
+        vt.tagId = tags[i];
+        vt.tagName = desc->getTagName(tags[i]);
+        vt.tagType = (CameraMetadataType) desc->getTagType(tags[i]);
+        ssize_t sectionIdx = desc->getSectionIndex(tags[i]);
+        tagsBySection[sectionIdx].push_back(vt);
+    }
+    mVendorTagSections.resize(numSections);
+    for (size_t s = 0; s < numSections; s++) {
+        mVendorTagSections[s].sectionName = (*sectionNames)[s].string();
+        mVendorTagSections[s].tags = tagsBySection[s];
+    }
+    return true;
+}
+
+// Methods from ::android::hardware::camera::provider::V2_4::ICameraProvider follow.
+Return<Status> CameraProvider::setCallback(const sp<ICameraProviderCallback>& callback)  {
+    {
+        Mutex::Autolock _l(mCbLock);
+        mCallbacks = callback;
+    } // release lock here because HAL might send callbacks in setCallbacks call
+    return getHidlStatus(mModule->setCallbacks(this));
+}
+
+Return<void> CameraProvider::getVendorTags(getVendorTags_cb _hidl_cb)  {
+    _hidl_cb(Status::OK, mVendorTagSections);
+    return Void();
+}
+
+Return<void> CameraProvider::getCameraIdList(getCameraIdList_cb _hidl_cb)  {
+    std::vector<hidl_string> deviceNameList;
+    for (auto const& deviceNamePair : mCameraDeviceNames) {
+        if (mCameraStatusMap[deviceNamePair.first] == CAMERA_DEVICE_STATUS_PRESENT) {
+            deviceNameList.push_back(deviceNamePair.second);
+        }
+    }
+    hidl_vec<hidl_string> hidlDeviceNameList(deviceNameList);
+    _hidl_cb (Status::OK, hidlDeviceNameList);
+    return Void();
+}
+
+Return<void> CameraProvider::isSetTorchModeSupported(isSetTorchModeSupported_cb _hidl_cb) {
+    bool support = mModule->isSetTorchModeSupported();
+    _hidl_cb (Status::OK, support);
+    return Void();
+}
+
+Return<void> CameraProvider::getCameraDeviceInterface_V1_x(const hidl_string& /*cameraDeviceName*/, getCameraDeviceInterface_V1_x_cb /*_hidl_cb*/)  {
+    // TODO implement after device 1.0 is implemented
+    return Void();
+}
+
+Return<void> CameraProvider::getCameraDeviceInterface_V3_x(const hidl_string& cameraDeviceName, getCameraDeviceInterface_V3_x_cb _hidl_cb)  {
+    std::smatch sm;
+    bool match = matchDeviceName(cameraDeviceName, sm);
+    if (!match) {
+        _hidl_cb(Status::ILLEGAL_ARGUMENT, nullptr);
+        return Void();
+    }
+
+    std::string cameraId = sm[2];
+    std::string deviceName(cameraDeviceName.c_str());
+    ssize_t index = mCameraDeviceNames.indexOf(std::make_pair(cameraId, deviceName));
+    if (index == NAME_NOT_FOUND) { // Either an illegal name or a device version mismatch
+        Status status = Status::OK;
+        ssize_t idx = mCameraIds.indexOf(cameraId);
+        if (idx == NAME_NOT_FOUND) {
+            status = Status::ILLEGAL_ARGUMENT;
+        } else { // invalid version
+            status = Status::OPERATION_NOT_SUPPORTED;
+        }
+        _hidl_cb(status, nullptr);
+        return Void();
+    }
+
+    if (mCameraStatusMap.count(cameraId) == 0 ||
+            mCameraStatusMap[cameraId] != CAMERA_DEVICE_STATUS_PRESENT) {
+        _hidl_cb(Status::ILLEGAL_ARGUMENT, nullptr);
+        return Void();
+    }
+
+    // TODO: we also need to keep a wp list of all generated devices to notify
+    //       devices of device present status change, but then each device might
+    //       need a sp<provider> to keep provider alive until all device closed?
+    //       Problem: do we have external camera products to test this?
+    sp<android::hardware::camera::device::V3_2::implementation::CameraDevice> device =
+            new android::hardware::camera::device::V3_2::implementation::CameraDevice(
+                    mModule, cameraId, mCameraDeviceNames);
+
+    if (device == nullptr) {
+        ALOGE("%s: cannot allocate camera device!", __FUNCTION__);
+        _hidl_cb(Status::INTERNAL_ERROR, nullptr);
+        return Void();
+    }
+
+    if (device->isInitFailed()) {
+        ALOGE("%s: camera device init failed!", __FUNCTION__);
+        device = nullptr;
+        _hidl_cb(Status::INTERNAL_ERROR, nullptr);
+        return Void();
+    }
+
+    _hidl_cb (Status::OK, device);
+    return Void();
+}
+
+ICameraProvider* HIDL_FETCH_ICameraProvider(const char* name) {
+    if (strcmp(name, kLegacyProviderName) != 0) {
+        return nullptr;
+    }
+    CameraProvider* provider = new CameraProvider();
+    if (provider == nullptr) {
+        ALOGE("%s: cannot allocate camera provider!", __FUNCTION__);
+        return nullptr;
+    }
+    if (provider->isInitFailed()) {
+        ALOGE("%s: camera provider init failed!", __FUNCTION__);
+        delete provider;
+        return nullptr;
+    }
+    return provider;
+}
+
+} // namespace implementation
+}  // namespace V2_4
+}  // namespace provider
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
diff --git a/camera/provider/2.4/default/CameraProvider.h b/camera/provider/2.4/default/CameraProvider.h
new file mode 100644
index 0000000..79899d9
--- /dev/null
+++ b/camera/provider/2.4/default/CameraProvider.h
@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef ANDROID_HARDWARE_CAMERA_PROVIDER_V2_4_CAMERAPROVIDER_H
+#define ANDROID_HARDWARE_CAMERA_PROVIDER_V2_4_CAMERAPROVIDER_H
+
+#include "hardware/camera_common.h"
+#include "utils/Mutex.h"
+#include "utils/SortedVector.h"
+#include <android/hardware/camera/provider/2.4/ICameraProvider.h>
+#include <hidl/Status.h>
+#include <hidl/MQDescriptor.h>
+#include "CameraModule.h"
+#include "VendorTagDescriptor.h"
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace provider {
+namespace V2_4 {
+namespace implementation {
+
+using ::android::hardware::camera::common::V1_0::CameraDeviceStatus;
+using ::android::hardware::camera::common::V1_0::Status;
+using ::android::hardware::camera::common::V1_0::TorchModeStatus;
+using ::android::hardware::camera::common::V1_0::VendorTag;
+using ::android::hardware::camera::common::V1_0::VendorTagSection;
+using ::android::hardware::camera::common::V1_0::helper::CameraModule;
+using ::android::hardware::camera::common::V1_0::helper::VendorTagDescriptor;
+using ::android::hardware::camera::provider::V2_4::ICameraProvider;
+using ::android::hardware::camera::provider::V2_4::ICameraProviderCallback;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::hidl_string;
+using ::android::sp;
+using ::android::Mutex;
+
+struct CameraProvider : public ICameraProvider, public camera_module_callbacks_t {
+    CameraProvider();
+    ~CameraProvider();
+
+    // Caller must use this method to check if CameraProvider ctor failed
+    bool isInitFailed() { return mInitFailed; }
+
+    // Methods from ::android::hardware::camera::provider::V2_4::ICameraProvider follow.
+    Return<Status> setCallback(const sp<ICameraProviderCallback>& callback) override;
+    Return<void> getVendorTags(getVendorTags_cb _hidl_cb) override;
+    Return<void> getCameraIdList(getCameraIdList_cb _hidl_cb) override;
+    Return<void> isSetTorchModeSupported(isSetTorchModeSupported_cb _hidl_cb) override;
+    Return<void> getCameraDeviceInterface_V1_x(const hidl_string& cameraDeviceName, getCameraDeviceInterface_V1_x_cb _hidl_cb) override;
+    Return<void> getCameraDeviceInterface_V3_x(const hidl_string& cameraDeviceName, getCameraDeviceInterface_V3_x_cb _hidl_cb) override;
+
+private:
+    Mutex mCbLock;
+    sp<ICameraProviderCallback> mCallbacks = nullptr;
+
+    sp<CameraModule> mModule;
+
+    int mNumberOfLegacyCameras;
+    std::map<std::string, camera_device_status_t> mCameraStatusMap; // camera id -> status
+    std::map<std::string, bool> mOpenLegacySupported; // camera id -> open_legacy HAL1.0 supported
+    SortedVector<std::string> mCameraIds; // the "0"/"1" legacy camera Ids
+    // (cameraId string, hidl device name) pairs
+    SortedVector<std::pair<std::string, std::string>> mCameraDeviceNames;
+
+    // Must be queried before using any APIs.
+    // APIs will only work when this returns true
+    bool mInitFailed;
+    bool initialize();
+
+    hidl_vec<VendorTagSection> mVendorTagSections;
+    bool setUpVendorTags();
+
+    // extract legacy camera ID/device version from a HIDL device name
+    static bool matchDeviceName(const hidl_string& deviceName, std::smatch& sm);
+    static std::string getLegacyCameraId(const hidl_string& deviceName);
+    static int getCameraDeviceVersion(const hidl_string& deviceName);
+
+    // create HIDL device name from camera ID and device version
+    static std::string getHidlDeviceName(std::string cameraId, int deviceVersion);
+
+    // convert conventional HAL status to HIDL Status
+    static Status getHidlStatus(int);
+
+    // static callback forwarding methods
+    static void sCameraDeviceStatusChange(
+        const struct camera_module_callbacks* callbacks,
+        int camera_id,
+        int new_status);
+    static void sTorchModeStatusChange(
+        const struct camera_module_callbacks* callbacks,
+        const char* camera_id,
+        int new_status);
+};
+
+extern "C" ICameraProvider* HIDL_FETCH_ICameraProvider(const char* name);
+
+}  // namespace implementation
+}  // namespace V2_4
+}  // namespace provider
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
+
+#endif  // ANDROID_HARDWARE_CAMERA_PROVIDER_V2_4_CAMERAPROVIDER_H