diff --git a/media/mtp/Android.mk b/media/mtp/Android.mk
index 70dc340..c25285e 100644
--- a/media/mtp/Android.mk
+++ b/media/mtp/Android.mk
@@ -21,7 +21,6 @@
 include $(CLEAR_VARS)
 
 LOCAL_SRC_FILES:=                                       \
-                  MtpClient.cpp                         \
                   MtpDataPacket.cpp                     \
                   MtpDebug.cpp                          \
                   MtpDevice.cpp                         \
@@ -53,7 +52,6 @@
 include $(CLEAR_VARS)
 
 LOCAL_SRC_FILES:=                                       \
-                  MtpClient.cpp                         \
                   MtpDataPacket.cpp                     \
                   MtpDebug.cpp                          \
                   MtpDevice.cpp                         \
diff --git a/media/mtp/MtpClient.cpp b/media/mtp/MtpClient.cpp
deleted file mode 100644
index c830540..0000000
--- a/media/mtp/MtpClient.cpp
+++ /dev/null
@@ -1,251 +0,0 @@
-/*
- * Copyright (C) 2010 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 "MtpClient"
-
-#include "MtpDebug.h"
-#include "MtpClient.h"
-#include "MtpDevice.h"
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <sys/types.h>
-#include <sys/ioctl.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <errno.h>
-
-#include <usbhost/usbhost.h>
-
-struct usb_device;
-
-namespace android {
-
-static bool isMtpDevice(uint16_t vendor, uint16_t product) {
-    // Sandisk Sansa Fuze
-    if (vendor == 0x0781 && product == 0x74c2)
-        return true;
-    // Samsung YP-Z5
-    if (vendor == 0x04e8 && product == 0x503c)
-        return true;
-    return false;
-}
-
-class MtpClientThread : public Thread {
-private:
-    MtpClient*   mClient;
-
-public:
-    MtpClientThread(MtpClient* client)
-        : mClient(client)
-    {
-    }
-
-    virtual bool threadLoop() {
-        return mClient->threadLoop();
-    }
-};
-
-
-MtpClient::MtpClient()
-    :   mThread(NULL),
-        mUsbHostContext(NULL),
-        mDone(false)
-{
-}
-
-MtpClient::~MtpClient() {
-    usb_host_cleanup(mUsbHostContext);
-}
-
-bool MtpClient::start() {
-    Mutex::Autolock autoLock(mMutex);
-
-    if (mThread)
-        return true;
-
-    mUsbHostContext = usb_host_init();
-    if (!mUsbHostContext)
-        return false;
-
-    mThread = new MtpClientThread(this);
-    mThread->run("MtpClientThread");
-    // wait for the thread to do initial device discovery before returning
-    mThreadStartCondition.wait(mMutex);
-
-    return true;
-}
-
-void MtpClient::stop() {
-    mDone = true;
-}
-
-MtpDevice* MtpClient::getDevice(int id) {
-    for (int i = 0; i < mDeviceList.size(); i++) {
-        MtpDevice* device = mDeviceList[i];
-        if (device->getID() == id)
-            return device;
-    }
-    return NULL;
-}
-
-bool MtpClient::usbDeviceAdded(const char *devname) {
-    struct usb_descriptor_header* desc;
-    struct usb_descriptor_iter iter;
-
-    struct usb_device *device = usb_device_open(devname);
-    if (!device) {
-        LOGE("usb_device_open failed\n");
-        return mDone;
-    }
-
-    usb_descriptor_iter_init(device, &iter);
-
-    while ((desc = usb_descriptor_iter_next(&iter)) != NULL) {
-        if (desc->bDescriptorType == USB_DT_INTERFACE) {
-            struct usb_interface_descriptor *interface = (struct usb_interface_descriptor *)desc;
-
-            if (interface->bInterfaceClass == USB_CLASS_STILL_IMAGE &&
-                interface->bInterfaceSubClass == 1 && // Still Image Capture
-                interface->bInterfaceProtocol == 1)     // Picture Transfer Protocol (PIMA 15470)
-            {
-                LOGD("Found camera: \"%s\" \"%s\"\n", usb_device_get_manufacturer_name(device),
-                        usb_device_get_product_name(device));
-            } else if (interface->bInterfaceClass == 0xFF &&
-                    interface->bInterfaceSubClass == 0xFF &&
-                    interface->bInterfaceProtocol == 0) {
-                char* interfaceName = usb_device_get_string(device, interface->iInterface);
-                if (!interfaceName || strcmp(interfaceName, "MTP"))
-                    continue;
-                // Looks like an android style MTP device
-                LOGD("Found MTP device: \"%s\" \"%s\"\n", usb_device_get_manufacturer_name(device),
-                        usb_device_get_product_name(device));
-            } else {
-                // look for special cased devices based on vendor/product ID
-                // we are doing this mainly for testing purposes
-                uint16_t vendor = usb_device_get_vendor_id(device);
-                uint16_t product = usb_device_get_product_id(device);
-                if (!isMtpDevice(vendor, product)) {
-                    // not an MTP or PTP device
-                    continue;
-                }
-                // request MTP OS string and descriptor
-                // some music players need to see this before entering MTP mode.
-                char buffer[256];
-                memset(buffer, 0, sizeof(buffer));
-                int ret = usb_device_send_control(device,
-                        USB_DIR_IN|USB_RECIP_DEVICE|USB_TYPE_STANDARD,
-                        USB_REQ_GET_DESCRIPTOR, (USB_DT_STRING << 8) | 0xEE,
-                        0, sizeof(buffer), buffer);
-                printf("usb_device_send_control returned %d errno: %d\n", ret, errno);
-                if (ret > 0) {
-                    printf("got MTP string %s\n", buffer);
-                    ret = usb_device_send_control(device,
-                            USB_DIR_IN|USB_RECIP_DEVICE|USB_TYPE_VENDOR, 1,
-                            0, 4, sizeof(buffer), buffer);
-                    printf("OS descriptor got %d\n", ret);
-                } else {
-                    printf("no MTP string\n");
-                }
-            }
-
-            // if we got here, then we have a likely MTP or PTP device
-
-            // interface should be followed by three endpoints
-            struct usb_endpoint_descriptor *ep;
-            struct usb_endpoint_descriptor *ep_in_desc = NULL;
-            struct usb_endpoint_descriptor *ep_out_desc = NULL;
-            struct usb_endpoint_descriptor *ep_intr_desc = NULL;
-            for (int i = 0; i < 3; i++) {
-                ep = (struct usb_endpoint_descriptor *)usb_descriptor_iter_next(&iter);
-                if (!ep || ep->bDescriptorType != USB_DT_ENDPOINT) {
-                    LOGE("endpoints not found\n");
-                    return mDone;
-                }
-                if (ep->bmAttributes == USB_ENDPOINT_XFER_BULK) {
-                    if (ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK)
-                        ep_in_desc = ep;
-                    else
-                        ep_out_desc = ep;
-                } else if (ep->bmAttributes == USB_ENDPOINT_XFER_INT &&
-                    ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK) {
-                    ep_intr_desc = ep;
-                }
-            }
-            if (!ep_in_desc || !ep_out_desc || !ep_intr_desc) {
-                LOGE("endpoints not found\n");
-                return mDone;
-            }
-
-            if (usb_device_claim_interface(device, interface->bInterfaceNumber)) {
-                LOGE("usb_device_claim_interface failed errno: %d\n", errno);
-                return mDone;
-            }
-
-            MtpDevice* mtpDevice = new MtpDevice(device, interface->bInterfaceNumber,
-                        ep_in_desc, ep_out_desc, ep_intr_desc);
-            mDeviceList.add(mtpDevice);
-            mtpDevice->initialize();
-            deviceAdded(mtpDevice);
-            return mDone;
-        }
-    }
-
-    usb_device_close(device);
-    return mDone;
-}
-
-bool MtpClient::usbDeviceRemoved(const char *devname) {
-    for (int i = 0; i < mDeviceList.size(); i++) {
-        MtpDevice* device = mDeviceList[i];
-        if (!strcmp(devname, device->getDeviceName())) {
-            deviceRemoved(device);
-            mDeviceList.removeAt(i);
-            delete device;
-            LOGD("Camera removed!\n");
-            break;
-        }
-    }
-    return mDone;
-}
-
-bool MtpClient::usbDiscoveryDone() {
-    Mutex::Autolock autoLock(mMutex);
-    mThreadStartCondition.signal();
-    return mDone;
-}
-
-bool MtpClient::threadLoop() {
-    usb_host_run(mUsbHostContext, usb_device_added, usb_device_removed, usb_discovery_done, this);
-    return false;
-}
-
-int MtpClient::usb_device_added(const char *devname, void* client_data) {
-    LOGD("usb_device_added %s\n", devname);
-    return ((MtpClient *)client_data)->usbDeviceAdded(devname);
-}
-
-int MtpClient::usb_device_removed(const char *devname, void* client_data) {
-    LOGD("usb_device_removed %s\n", devname);
-    return ((MtpClient *)client_data)->usbDeviceRemoved(devname);
-}
-
-int MtpClient::usb_discovery_done(void* client_data) {
-    LOGD("usb_discovery_done\n");
-    return ((MtpClient *)client_data)->usbDiscoveryDone();
-}
-
-}  // namespace android
diff --git a/media/mtp/MtpClient.h b/media/mtp/MtpClient.h
deleted file mode 100644
index fa5c527..0000000
--- a/media/mtp/MtpClient.h
+++ /dev/null
@@ -1,68 +0,0 @@
-/*
- * Copyright (C) 2010 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 _MTP_CLIENT_H
-#define _MTP_CLIENT_H
-
-#include "MtpTypes.h"
-
-#include <utils/threads.h>
-
-struct usb_host_context;
-
-namespace android {
-
-class MtpClientThread;
-
-class MtpClient {
-private:
-    MtpDeviceList               mDeviceList;
-    MtpClientThread*            mThread;
-    Condition                   mThreadStartCondition;
-    Mutex                       mMutex;
-    struct usb_host_context*    mUsbHostContext;
-    bool                        mDone;
-
-public:
-                            MtpClient();
-    virtual                 ~MtpClient();
-
-    bool                    start();
-    void                    stop();
-
-    inline MtpDeviceList&   getDeviceList() { return mDeviceList; }
-    MtpDevice*              getDevice(int id);
-
-
-    virtual void            deviceAdded(MtpDevice *device) = 0;
-    virtual void            deviceRemoved(MtpDevice *device) = 0;
-
-private:
-    // these return true if we should stop monitoring USB and clean up
-    bool                    usbDeviceAdded(const char *devname);
-    bool                    usbDeviceRemoved(const char *devname);
-    bool                    usbDiscoveryDone();
-
-    friend class MtpClientThread;
-    bool                    threadLoop();
-    static int              usb_device_added(const char *devname, void* client_data);
-    static int              usb_device_removed(const char *devname, void* client_data);
-    static int              usb_discovery_done(void* client_data);
-};
-
-}; // namespace android
-
-#endif // _MTP_CLIENT_H
diff --git a/media/mtp/MtpDevice.cpp b/media/mtp/MtpDevice.cpp
index d22c72f..d02ed90 100644
--- a/media/mtp/MtpDevice.cpp
+++ b/media/mtp/MtpDevice.cpp
@@ -38,6 +38,121 @@
 
 namespace android {
 
+static bool isMtpDevice(uint16_t vendor, uint16_t product) {
+    // Sandisk Sansa Fuze
+    if (vendor == 0x0781 && product == 0x74c2)
+        return true;
+    // Samsung YP-Z5
+    if (vendor == 0x04e8 && product == 0x503c)
+        return true;
+    return false;
+}
+
+MtpDevice* MtpDevice::open(const char* deviceName, int fd) {
+    struct usb_device *device = usb_device_new(deviceName, fd);
+    if (!device) {
+        LOGE("usb_device_new failed for %s", deviceName);
+        return NULL;
+    }
+
+    struct usb_descriptor_header* desc;
+    struct usb_descriptor_iter iter;
+
+    usb_descriptor_iter_init(device, &iter);
+
+    while ((desc = usb_descriptor_iter_next(&iter)) != NULL) {
+        if (desc->bDescriptorType == USB_DT_INTERFACE) {
+            struct usb_interface_descriptor *interface = (struct usb_interface_descriptor *)desc;
+
+            if (interface->bInterfaceClass == USB_CLASS_STILL_IMAGE &&
+                interface->bInterfaceSubClass == 1 && // Still Image Capture
+                interface->bInterfaceProtocol == 1)     // Picture Transfer Protocol (PIMA 15470)
+            {
+                LOGD("Found camera: \"%s\" \"%s\"\n", usb_device_get_manufacturer_name(device),
+                        usb_device_get_product_name(device));
+            } else if (interface->bInterfaceClass == 0xFF &&
+                    interface->bInterfaceSubClass == 0xFF &&
+                    interface->bInterfaceProtocol == 0) {
+                char* interfaceName = usb_device_get_string(device, interface->iInterface);
+                if (!interfaceName || strcmp(interfaceName, "MTP"))
+                    continue;
+                // Looks like an android style MTP device
+                LOGD("Found MTP device: \"%s\" \"%s\"\n", usb_device_get_manufacturer_name(device),
+                        usb_device_get_product_name(device));
+            } else {
+                // look for special cased devices based on vendor/product ID
+                // we are doing this mainly for testing purposes
+                uint16_t vendor = usb_device_get_vendor_id(device);
+                uint16_t product = usb_device_get_product_id(device);
+                if (!isMtpDevice(vendor, product)) {
+                    // not an MTP or PTP device
+                    continue;
+                }
+                // request MTP OS string and descriptor
+                // some music players need to see this before entering MTP mode.
+                char buffer[256];
+                memset(buffer, 0, sizeof(buffer));
+                int ret = usb_device_send_control(device,
+                        USB_DIR_IN|USB_RECIP_DEVICE|USB_TYPE_STANDARD,
+                        USB_REQ_GET_DESCRIPTOR, (USB_DT_STRING << 8) | 0xEE,
+                        0, sizeof(buffer), buffer);
+                printf("usb_device_send_control returned %d errno: %d\n", ret, errno);
+                if (ret > 0) {
+                    printf("got MTP string %s\n", buffer);
+                    ret = usb_device_send_control(device,
+                            USB_DIR_IN|USB_RECIP_DEVICE|USB_TYPE_VENDOR, 1,
+                            0, 4, sizeof(buffer), buffer);
+                    printf("OS descriptor got %d\n", ret);
+                } else {
+                    printf("no MTP string\n");
+                }
+            }
+
+            // if we got here, then we have a likely MTP or PTP device
+
+            // interface should be followed by three endpoints
+            struct usb_endpoint_descriptor *ep;
+            struct usb_endpoint_descriptor *ep_in_desc = NULL;
+            struct usb_endpoint_descriptor *ep_out_desc = NULL;
+            struct usb_endpoint_descriptor *ep_intr_desc = NULL;
+            for (int i = 0; i < 3; i++) {
+                ep = (struct usb_endpoint_descriptor *)usb_descriptor_iter_next(&iter);
+                if (!ep || ep->bDescriptorType != USB_DT_ENDPOINT) {
+                    LOGE("endpoints not found\n");
+                    return NULL;
+                }
+                if (ep->bmAttributes == USB_ENDPOINT_XFER_BULK) {
+                    if (ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK)
+                        ep_in_desc = ep;
+                    else
+                        ep_out_desc = ep;
+                } else if (ep->bmAttributes == USB_ENDPOINT_XFER_INT &&
+                    ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK) {
+                    ep_intr_desc = ep;
+                }
+            }
+            if (!ep_in_desc || !ep_out_desc || !ep_intr_desc) {
+                LOGE("endpoints not found\n");
+                return NULL;
+            }
+
+            if (usb_device_claim_interface(device, interface->bInterfaceNumber)) {
+                LOGE("usb_device_claim_interface failed errno: %d\n", errno);
+                return NULL;
+            }
+
+            MtpDevice* mtpDevice = new MtpDevice(device, interface->bInterfaceNumber,
+                        ep_in_desc, ep_out_desc, ep_intr_desc);
+            mtpDevice->initialize();
+            return mtpDevice;
+        }
+    }
+
+    usb_device_close(device);
+    LOGE("device not found");
+    return NULL;
+}
+
 MtpDevice::MtpDevice(struct usb_device* device, int interface,
             const struct usb_endpoint_descriptor *ep_in,
             const struct usb_endpoint_descriptor *ep_out,
@@ -49,7 +164,6 @@
         mRequestOut(NULL),
         mRequestIntr(NULL),
         mDeviceInfo(NULL),
-        mID(usb_device_get_unique_id(device)),
         mSessionID(0),
         mTransactionID(0),
         mReceivedResponse(false)
@@ -430,6 +544,98 @@
     return NULL;
 }
 
+bool MtpDevice::readObject(MtpObjectHandle handle,
+        bool (* callback)(void* data, int offset, int length, void* clientData),
+        int objectSize, void* clientData) {
+    Mutex::Autolock autoLock(mMutex);
+    bool result = false;
+
+    mRequest.reset();
+    mRequest.setParameter(1, handle);
+    if (sendRequest(MTP_OPERATION_GET_OBJECT)
+            && mData.readDataHeader(mRequestIn1)) {
+        uint32_t length = mData.getContainerLength();
+        if (length - MTP_CONTAINER_HEADER_SIZE != objectSize) {
+            LOGE("readObject error objectSize: %d, length: %d",
+                    objectSize, length);
+            goto fail;
+        }
+        length -= MTP_CONTAINER_HEADER_SIZE;
+        uint32_t remaining = length;
+        int offset = 0;
+
+        int initialDataLength = 0;
+        void* initialData = mData.getData(initialDataLength);
+        if (initialData) {
+            if (initialDataLength > 0) {
+                if (!callback(initialData, 0, initialDataLength, clientData))
+                    goto fail;
+                remaining -= initialDataLength;
+                offset += initialDataLength;
+            }
+            free(initialData);
+        }
+
+        // USB reads greater than 16K don't work
+        char buffer1[16384], buffer2[16384];
+        mRequestIn1->buffer = buffer1;
+        mRequestIn2->buffer = buffer2;
+        struct usb_request* req = mRequestIn1;
+        void* writeBuffer = NULL;
+        int writeLength = 0;
+
+        while (remaining > 0 || writeBuffer) {
+            if (remaining > 0) {
+                // queue up a read request
+                req->buffer_length = (remaining > sizeof(buffer1) ? sizeof(buffer1) : remaining);
+                if (mData.readDataAsync(req)) {
+                    LOGE("readDataAsync failed");
+                    goto fail;
+                }
+            } else {
+                req = NULL;
+            }
+
+            if (writeBuffer) {
+                // write previous buffer
+                if (!callback(writeBuffer, offset, writeLength, clientData)) {
+                    LOGE("write failed");
+                    // wait for pending read before failing
+                    if (req)
+                        mData.readDataWait(mDevice);
+                    goto fail;
+                }
+                offset += writeLength;
+                writeBuffer = NULL;
+            }
+
+            // wait for read to complete
+            if (req) {
+                int read = mData.readDataWait(mDevice);
+                if (read < 0)
+                    goto fail;
+
+                if (read > 0) {
+                    writeBuffer = req->buffer;
+                    writeLength = read;
+                    remaining -= read;
+                    req = (req == mRequestIn1 ? mRequestIn2 : mRequestIn1);
+                } else {
+                    writeBuffer = NULL;
+                }
+            }
+        }
+
+        MtpResponseCode response = readResponse();
+        if (response == MTP_RESPONSE_OK)
+            result = true;
+    }
+
+fail:
+    return result;
+}
+
+
 // reads the object's data and writes it to the specified file path
 bool MtpDevice::readObject(MtpObjectHandle handle, const char* destPath, int group, int perm) {
     LOGD("readObject: %s", destPath);
@@ -507,10 +713,14 @@
                 if (read < 0)
                     goto fail;
 
-                writeBuffer = req->buffer;
-                writeLength = read;
-                remaining -= read;
-                req = (req == mRequestIn1 ? mRequestIn2 : mRequestIn1);
+                if (read > 0) {
+                    writeBuffer = req->buffer;
+                    writeLength = read;
+                    remaining -= read;
+                    req = (req == mRequestIn1 ? mRequestIn2 : mRequestIn1);
+                } else {
+                    writeBuffer = NULL;
+                }
             }
         }
 
diff --git a/media/mtp/MtpDevice.h b/media/mtp/MtpDevice.h
index d0a0fb3..b69203e 100644
--- a/media/mtp/MtpDevice.h
+++ b/media/mtp/MtpDevice.h
@@ -45,9 +45,6 @@
     MtpDeviceInfo*          mDeviceInfo;
     MtpPropertyList         mDeviceProperties;
 
-    // a unique ID for the device
-    int                     mID;
-
     // current session ID
     MtpSessionID            mSessionID;
     // current transaction ID
@@ -67,9 +64,10 @@
                                     const struct usb_endpoint_descriptor *ep_in,
                                     const struct usb_endpoint_descriptor *ep_out,
                                     const struct usb_endpoint_descriptor *ep_intr);
-    virtual                 ~MtpDevice();
 
-    inline int              getID() const { return mID; }
+    static MtpDevice*       open(const char* deviceName, int fd);
+
+    virtual                 ~MtpDevice();
 
     void                    initialize();
     void                    close();
@@ -97,7 +95,11 @@
     MtpProperty*            getDevicePropDesc(MtpDeviceProperty code);
     MtpProperty*            getObjectPropDesc(MtpObjectProperty code, MtpObjectFormat format);
 
-    bool                   readObject(MtpObjectHandle handle, const char* destPath, int group,
+    bool                    readObject(MtpObjectHandle handle,
+                                    bool (* callback)(void* data, int offset,
+                                            int length, void* clientData),
+                                    int objectSize, void* clientData);
+    bool                    readObject(MtpObjectHandle handle, const char* destPath, int group,
                                     int perm);
 
 private: