Introducing chrome.usb.getDevices/openDevice API

chrome/browser/extensions/api/usb/usb_api.cc

Index: chrome/browser/extensions/api/usb/usb_api.cc
diff --git a/chrome/browser/extensions/api/usb/usb_api.cc b/chrome/browser/extensions/api/usb/usb_api.cc
index c8ec84863937b6b863acd357aac00f0bcdc081b6..e6ca32719227234f0c338b134e3f11198121cd34 100644
--- a/chrome/browser/extensions/api/usb/usb_api.cc
+++ b/chrome/browser/extensions/api/usb/usb_api.cc
@@ -8,6 +8,7 @@
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
+#include "base/message_loop/message_loop_proxy.h"
 #include "chrome/browser/extensions/api/usb/usb_device_resource.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/profiles/profile.h"
@@ -17,24 +18,27 @@
 #include "chrome/common/extensions/permissions/permissions_data.h"
 #include "chrome/common/extensions/permissions/usb_device_permission.h"
 
-namespace BulkTransfer = extensions::api::usb::BulkTransfer;
-namespace ClaimInterface = extensions::api::usb::ClaimInterface;
-namespace ListInterfaces = extensions::api::usb::ListInterfaces;
-namespace CloseDevice = extensions::api::usb::CloseDevice;
-namespace ControlTransfer = extensions::api::usb::ControlTransfer;
-namespace FindDevices = extensions::api::usb::FindDevices;
-namespace InterruptTransfer = extensions::api::usb::InterruptTransfer;
-namespace IsochronousTransfer = extensions::api::usb::IsochronousTransfer;
-namespace ReleaseInterface = extensions::api::usb::ReleaseInterface;
-namespace ResetDevice = extensions::api::usb::ResetDevice;
-namespace SetInterfaceAlternateSetting =
-    extensions::api::usb::SetInterfaceAlternateSetting;
 namespace usb = extensions::api::usb;
+namespace BulkTransfer = usb::BulkTransfer;
+namespace ClaimInterface = usb::ClaimInterface;
+namespace CloseDevice = usb::CloseDevice;
+namespace ControlTransfer = usb::ControlTransfer;
+namespace FindDevices = usb::FindDevices;
+namespace GetDevices = usb::GetDevices;
+namespace InterruptTransfer = usb::InterruptTransfer;
+namespace IsochronousTransfer = usb::IsochronousTransfer;
+namespace ListInterfaces = usb::ListInterfaces;
+namespace OpenDevice = usb::OpenDevice;
+namespace ReleaseInterface = usb::ReleaseInterface;
+namespace RequestAccess = usb::RequestAccess;
+namespace ResetDevice = usb::ResetDevice;
+namespace SetInterfaceAlternateSetting = usb::SetInterfaceAlternateSetting;
 
 using content::BrowserThread;
 using std::string;
 using std::vector;
 using usb::ControlTransferInfo;
+using usb::ConnectionHandle;
 using usb::Device;
 using usb::Direction;
 using usb::EndpointDescriptor;
@@ -47,52 +51,56 @@ using usb::SynchronizationType;
 using usb::TransferType;
 using usb::UsageType;
 
+typedef std::vector<scoped_refptr<UsbDevice> > DeviceVector;
+typedef scoped_ptr<DeviceVector> ScopedDeviceVector;
+
 namespace {
 
-static const char kDataKey[] = "data";
-static const char kResultCodeKey[] = "resultCode";
-
-static const char kErrorCancelled[] = "Transfer was cancelled.";
-static const char kErrorDisconnect[] = "Device disconnected.";
-static const char kErrorGeneric[] = "Transfer failed.";
-static const char kErrorOverflow[] = "Inbound transfer overflow.";
-static const char kErrorStalled[] = "Transfer stalled.";
-static const char kErrorTimeout[] = "Transfer timed out.";
-static const char kErrorTransferLength[] = "Transfer length is insufficient.";
-
-static const char kErrorCannotListInterfaces[] = "Error listing interfaces.";
-static const char kErrorCannotClaimInterface[] = "Error claiming interface.";
-static const char kErrorCannotReleaseInterface[] = "Error releasing interface.";
-static const char kErrorCannotSetInterfaceAlternateSetting[] =
+const char kDataKey[] = "data";
+const char kResultCodeKey[] = "resultCode";
+
+const char kErrorOpen[] = "Failed to open device.";
+const char kErrorCancelled[] = "Transfer was cancelled.";
+const char kErrorDisconnect[] = "Device disconnected.";
+const char kErrorGeneric[] = "Transfer failed.";
+const char kErrorNotSupported[] = "Not supported on this platform.";
+const char kErrorOverflow[] = "Inbound transfer overflow.";
+const char kErrorStalled[] = "Transfer stalled.";
+const char kErrorTimeout[] = "Transfer timed out.";
+const char kErrorTransferLength[] = "Transfer length is insufficient.";
+
+const char kErrorCannotListInterfaces[] = "Error listing interfaces.";
+const char kErrorCannotClaimInterface[] = "Error claiming interface.";
+const char kErrorCannotReleaseInterface[] = "Error releasing interface.";
+const char kErrorCannotSetInterfaceAlternateSetting[] =
     "Error setting alternate interface setting.";
-static const char kErrorConvertDirection[] = "Invalid transfer direction.";
-static const char kErrorConvertRecipient[] = "Invalid transfer recipient.";
-static const char kErrorConvertRequestType[] = "Invalid request type.";
-static const char kErrorConvertSynchronizationType[] =
-    "Invalid synchronization type";
-static const char kErrorConvertTransferType[] = "Invalid endpoint type.";
-static const char kErrorConvertUsageType[] = "Invalid usage type.";
-static const char kErrorMalformedParameters[] = "Error parsing parameters.";
-static const char kErrorNoDevice[] = "No such device.";
-static const char kErrorPermissionDenied[] =
+const char kErrorConvertDirection[] = "Invalid transfer direction.";
+const char kErrorConvertRecipient[] = "Invalid transfer recipient.";
+const char kErrorConvertRequestType[] = "Invalid request type.";
+const char kErrorConvertSynchronizationType[] = "Invalid synchronization type";
+const char kErrorConvertTransferType[] = "Invalid endpoint type.";
+const char kErrorConvertUsageType[] = "Invalid usage type.";
+const char kErrorMalformedParameters[] = "Error parsing parameters.";
+const char kErrorNoDevice[] = "No such device.";
+const char kErrorPermissionDenied[] =
     "Permission to access device was denied";
-static const char kErrorInvalidTransferLength[] = "Transfer length must be a "
-    "positive number less than 104,857,600.";
-static const char kErrorInvalidNumberOfPackets[] = "Number of packets must be "
-    "a positive number less than 4,194,304.";
-static const char kErrorInvalidPacketLength[] = "Packet length must be a "
+const char kErrorInvalidTransferLength[] =
+    "Transfer length must be a positive number less than 104,857,600.";
+const char kErrorInvalidNumberOfPackets[] =
+    "Number of packets must be a positive number less than 4,194,304.";
+const char kErrorInvalidPacketLength[] = "Packet length must be a "
     "positive number less than 65,536.";
-static const char kErrorResetDevice[] =
+const char kErrorResetDevice[] =
     "Error resetting the device. The device has been closed.";
 
-static const size_t kMaxTransferLength = 100 * 1024 * 1024;
-static const int kMaxPackets = 4 * 1024 * 1024;
-static const int kMaxPacketLength = 64 * 1024;
+const size_t kMaxTransferLength = 100 * 1024 * 1024;
+const int kMaxPackets = 4 * 1024 * 1024;
+const int kMaxPacketLength = 64 * 1024;
 
-static UsbDevice* g_device_for_test = NULL;
+UsbDevice* g_device_for_test = NULL;
 
-static bool ConvertDirectionToApi(const UsbEndpointDirection& input,
-                                  Direction* output) {
+bool ConvertDirectionToApi(const UsbEndpointDirection& input,
+                           Direction* output) {
   switch (input) {
     case USB_DIRECTION_INBOUND:
       *output = usb::DIRECTION_IN;
@@ -106,9 +114,8 @@ static bool ConvertDirectionToApi(const UsbEndpointDirection& input,
   }
 }
 
-static bool ConvertSynchronizationTypeToApi(
-    const UsbSynchronizationType& input,
-    extensions::api::usb::SynchronizationType* output) {
+bool ConvertSynchronizationTypeToApi(const UsbSynchronizationType& input,
+                                     usb::SynchronizationType* output) {
   switch (input) {
     case USB_SYNCHRONIZATION_NONE:
       *output = usb::SYNCHRONIZATION_TYPE_NONE;
@@ -128,9 +135,9 @@ static bool ConvertSynchronizationTypeToApi(
   }
 }
 
-static bool ConvertTransferTypeToApi(
+bool ConvertTransferTypeToApi(
     const UsbTransferType& input,
-    extensions::api::usb::TransferType* output) {
+    usb::TransferType* output) {
   switch (input) {
     case USB_TRANSFER_CONTROL:
       *output = usb::TRANSFER_TYPE_CONTROL;
@@ -150,8 +157,7 @@ static bool ConvertTransferTypeToApi(
   }
 }
 
-static bool ConvertUsageTypeToApi(const UsbUsageType& input,
-    extensions::api::usb::UsageType* output) {
+bool ConvertUsageTypeToApi(const UsbUsageType& input, usb::UsageType* output) {
   switch (input) {
     case USB_USAGE_DATA:
       *output = usb::USAGE_TYPE_DATA;
@@ -168,8 +174,8 @@ static bool ConvertUsageTypeToApi(const UsbUsageType& input,
   }
 }
 
-static bool ConvertDirection(const Direction& input,
-                             UsbEndpointDirection* output) {
+bool ConvertDirection(const Direction& input,
+                      UsbEndpointDirection* output) {
   switch (input) {
     case usb::DIRECTION_IN:
       *output = USB_DIRECTION_INBOUND;
@@ -183,8 +189,8 @@ static bool ConvertDirection(const Direction& input,
   }
 }
 
-static bool ConvertRequestType(const RequestType& input,
-                               UsbDeviceHandle::TransferRequestType* output) {
+bool ConvertRequestType(const RequestType& input,
+                        UsbDeviceHandle::TransferRequestType* output) {
   switch (input) {
     case usb::REQUEST_TYPE_STANDARD:
       *output = UsbDeviceHandle::STANDARD;
@@ -204,8 +210,8 @@ static bool ConvertRequestType(const RequestType& input,
   }
 }
 
-static bool ConvertRecipient(const Recipient& input,
-                             UsbDeviceHandle::TransferRecipient* output) {
+bool ConvertRecipient(const Recipient& input,
+                      UsbDeviceHandle::TransferRecipient* output) {
   switch (input) {
     case usb::RECIPIENT_DEVICE:
       *output = UsbDeviceHandle::DEVICE;
@@ -226,7 +232,7 @@ static bool ConvertRecipient(const Recipient& input,
 }
 
 template<class T>
-static bool GetTransferSize(const T& input, size_t* output) {
+bool GetTransferSize(const T& input, size_t* output) {
   if (input.direction == usb::DIRECTION_IN) {
     const int* length = input.length.get();
     if (length && *length >= 0 &&
@@ -244,7 +250,7 @@ static bool GetTransferSize(const T& input, size_t* output) {
 }
 
 template<class T>
-static scoped_refptr<net::IOBuffer> CreateBufferForTransfer(
+scoped_refptr<net::IOBuffer> CreateBufferForTransfer(
     const T& input, UsbEndpointDirection direction, size_t size) {
 
   if (size >= kMaxTransferLength)
@@ -268,8 +274,7 @@ static scoped_refptr<net::IOBuffer> CreateBufferForTransfer(
   return NULL;
 }
 
-static const char* ConvertTransferStatusToErrorString(
-    const UsbTransferStatus status) {
+const char* ConvertTransferStatusToErrorString(const UsbTransferStatus status) {
   switch (status) {
     case USB_TRANSFER_COMPLETED:
       return "";
@@ -293,7 +298,37 @@ static const char* ConvertTransferStatusToErrorString(
   }
 }
 
-static base::DictionaryValue* CreateTransferInfo(
+#if defined(OS_CHROMEOS)
+void RequestUsbDevicesAccessHelper(
+    std::vector<scoped_refptr<UsbDevice> >* devices,
+    std::vector<scoped_refptr<UsbDevice> >::iterator i,
+    int interface_id,
+    const base::Closure& callback,
+    bool success) {
+  if (success) {
+    ++i;
+  } else {
+    i = devices->erase(i);
+  }
+  if (i == devices->end()) {
+    callback.Run();
+    return;
+  }
+  (*i)->RequestUsbAcess(interface_id,
+                        base::Bind(RequestUsbDevicesAccessHelper, devices, i,
+                                   interface_id, callback));
+}
+
+void RequestUsbDevicesAccess(
+    std::vector<scoped_refptr<UsbDevice> >* devices,
+    int interface_id,
+    const base::Closure& callback) {
+  RequestUsbDevicesAccessHelper(devices, devices->begin(), interface_id,
+                               callback, true);
+}
+#endif  // OS_CHROMEOS
+
+base::DictionaryValue* CreateTransferInfo(
     UsbTransferStatus status,
     scoped_refptr<net::IOBuffer> data,
     size_t length) {
@@ -304,18 +339,30 @@ static base::DictionaryValue* CreateTransferInfo(
   return result;
 }
 
-static base::Value* PopulateDevice(int handle, int vendor_id, int product_id) {
-  Device device;
-  device.handle = handle;
-  device.vendor_id = vendor_id;
-  device.product_id = product_id;
-  return device.ToValue().release();
+base::Value* PopulateConnectionHandle(int handle, int vendor_id,
+                                      int product_id) {
+  ConnectionHandle result;
+  result.handle = handle;
+  result.vendor_id = vendor_id;
+  result.product_id = product_id;
+  return result.ToValue().release();
+}
+
+base::Value* PopulateDevice(UsbDevice* device) {
+  Device result;
+  result.device = device->unique_id();
+  result.vendor_id = device->vendor_id();
+  result.product_id = device->product_id();
+  return result.ToValue().release();
 }
 
-static base::Value* PopulateInterfaceDescriptor(int interface_number,
-        int alternate_setting, int interface_class, int interface_subclass,
-        int interface_protocol,
-        std::vector<linked_ptr<EndpointDescriptor> >* endpoints) {
+base::Value* PopulateInterfaceDescriptor(
+    int interface_number,
+    int alternate_setting,
+    int interface_class,
+    int interface_subclass,
+    int interface_protocol,
+    std::vector<linked_ptr<EndpointDescriptor> >* endpoints) {
   InterfaceDescriptor descriptor;
   descriptor.interface_number = interface_number;
   descriptor.alternate_setting = alternate_setting;
@@ -347,9 +394,62 @@ bool UsbAsyncApiFunction::Respond() {
   return error_.empty();
 }
 
-UsbDeviceResource* UsbAsyncApiFunction::GetUsbDeviceResource(
-    int api_resource_id) {
-  return manager_->Get(extension_->id(), api_resource_id);
+scoped_refptr<UsbDevice>
+UsbAsyncApiFunction::GetDeviceOrOrCompleteWithError(
+    const Device& input_device) {
+  if (g_device_for_test)
+    return g_device_for_test;
+
+  const uint16_t vendor_id = input_device.vendor_id;
+  const uint16_t product_id = input_device.product_id;
+  UsbDevicePermission::CheckParam param(
+      vendor_id, product_id, UsbDevicePermissionData::UNSPECIFIED_INTERFACE);
+  if (!PermissionsData::CheckAPIPermissionWithParam(
+          GetExtension(), APIPermission::kUsbDevice, &param)) {
+    LOG(WARNING) << "Insufficient permissions to access device.";
+    CompleteWithError(kErrorPermissionDenied);
+    return NULL;
+  }
+
+  UsbService* service = UsbService::GetInstance();
+  scoped_refptr<UsbDevice> device;
+
+  device = service->GetDeviceById(input_device.device);
+
+  if (!device) {
+    CompleteWithError(kErrorNoDevice);
+    return NULL;
+  }
+
+  if (device->vendor_id() != input_device.vendor_id ||
+      device->product_id() != input_device.product_id) {
+    // Must act as if there is no such a device.
+    // Otherwise can be used to finger print unauthorized devices.
+    CompleteWithError(kErrorNoDevice);
+    return NULL;
+  }
+
+  return device;
+}
+
+scoped_refptr<UsbDeviceHandle>
+UsbAsyncApiFunction::GetDeviceHandleOrCompleteWithError(
+    const ConnectionHandle& input_device_handle) {
+  UsbDeviceResource* resource =
+      manager_->Get(extension_->id(), input_device_handle.handle);
+  if (!resource) {
+    CompleteWithError(kErrorNoDevice);
+    return NULL;
+  }
+  if (resource->device()->device()->vendor_id() !=
+          input_device_handle.vendor_id ||
+      resource->device()->device()->product_id() !=
+          input_device_handle.product_id) {
+    CompleteWithError(kErrorNoDevice);
+    return NULL;
+  }
+
+  return resource->device();
 }
 
 void UsbAsyncApiFunction::RemoveUsbDeviceResource(int api_resource_id) {
@@ -403,10 +503,6 @@ UsbFindDevicesFunction::UsbFindDevicesFunction() {}
 
 UsbFindDevicesFunction::~UsbFindDevicesFunction() {}
 
-void UsbFindDevicesFunction::SetDeviceForTest(UsbDevice* device) {
-  g_device_for_test = device;
-}
-
 bool UsbFindDevicesFunction::Prepare() {
   parameters_ = FindDevices::Params::Create(*args_);
   EXTENSION_FUNCTION_VALIDATE(parameters_.get());
@@ -414,16 +510,15 @@ bool UsbFindDevicesFunction::Prepare() {
 }
 
 void UsbFindDevicesFunction::AsyncWorkStart() {
-  result_.reset(new base::ListValue());
+  scoped_ptr<base::ListValue> result(new base::ListValue());
 
   if (g_device_for_test) {
     UsbDeviceResource* const resource = new UsbDeviceResource(
         extension_->id(),
         g_device_for_test->Open());
 
-    Device device;
-    result_->Append(PopulateDevice(manager_->Add(resource), 0, 0));
-    SetResult(result_.release());
+    result->Append(PopulateConnectionHandle(manager_->Add(resource), 0, 0));
+    SetResult(result.release());
     AsyncWorkCompleted();
     return;
   }
@@ -442,14 +537,34 @@ void UsbFindDevicesFunction::AsyncWorkStart() {
   }
 
   UsbService *service = UsbService::GetInstance();
-  service->FindDevices(
-      vendor_id, product_id, interface_id,
-      base::Bind(&UsbFindDevicesFunction::EnumerationCompletedFileThread,
-                 this));
+  ScopedDeviceVector devices(new DeviceVector());
+  service->GetDevices(devices.get());
+
+  for (DeviceVector::iterator it = devices->begin();
+      it != devices->end();) {
+    if ((*it)->vendor_id() != vendor_id || (*it)->product_id() != product_id) {
+      it = devices->erase(it);
+    } else {
+      ++it;
+    }
+  }
+
+#if defined(OS_CHROMEOS)
+  if (parameters_->options.interface_id.get()) {
+    int interface_id = *parameters_->options.interface_id.get();
+    RequestUsbDevicesAccess(devices.get(), interface_id,
+                            base::Bind(&UsbFindDevicesFunction::OpenDevices,
+                                       this,
+                                       base::Passed(devices.Pass())));
+    return;
+  }
+#endif  // OS_CHROMEOS
+  OpenDevices(devices.Pass());
 }
 
-void UsbFindDevicesFunction::EnumerationCompletedFileThread(
-    scoped_ptr<std::vector<scoped_refptr<UsbDevice> > > devices) {
+void UsbFindDevicesFunction::OpenDevices(ScopedDeviceVector devices) {
+  base::ListValue* result = new base::ListValue();
+
   for (size_t i = 0; i < devices->size(); ++i) {
     scoped_refptr<UsbDeviceHandle> device_handle =
       devices->at(i)->Open();
@@ -462,12 +577,128 @@ void UsbFindDevicesFunction::EnumerationCompletedFileThread(
     UsbDeviceResource* const resource =
         new UsbDeviceResource(extension_->id(), device_handle);
 
-    result_->Append(PopulateDevice(manager_->Add(resource),
-                                   parameters_->options.vendor_id,
-                                   parameters_->options.product_id));
+    result->Append(PopulateConnectionHandle(manager_->Add(resource),
+                                             parameters_->options.vendor_id,
+                                             parameters_->options.product_id));
   }
 
-  SetResult(result_.release());
+  SetResult(result);
+  AsyncWorkCompleted();
+}
+
+UsbGetDevicesFunction::UsbGetDevicesFunction() {
+}
+
+UsbGetDevicesFunction::~UsbGetDevicesFunction() {
+}
+
+void UsbGetDevicesFunction::SetDeviceForTest(UsbDevice* device) {
+  g_device_for_test = device;
+}
+
+bool UsbGetDevicesFunction::Prepare() {
+  parameters_ = GetDevices::Params::Create(*args_);
+  EXTENSION_FUNCTION_VALIDATE(parameters_.get());
+  return true;
+}
+
+void UsbGetDevicesFunction::AsyncWorkStart() {
+  scoped_ptr<base::ListValue> result(new base::ListValue());
+
+  if (g_device_for_test) {
+    result->Append(PopulateDevice(g_device_for_test));
+    SetResult(result.release());
+    AsyncWorkCompleted();
+    return;
+  }
+
+  const uint16_t vendor_id = parameters_->options.vendor_id;
+  const uint16_t product_id = parameters_->options.product_id;
+  UsbDevicePermission::CheckParam param(
+      vendor_id, product_id, UsbDevicePermissionData::UNSPECIFIED_INTERFACE);
+  if (!PermissionsData::CheckAPIPermissionWithParam(
+          GetExtension(), APIPermission::kUsbDevice, &param)) {
+    LOG(WARNING) << "Insufficient permissions to access device.";
+    CompleteWithError(kErrorPermissionDenied);
+    return;
+  }
+
+  UsbService* service = UsbService::GetInstance();
+  DeviceVector devices;
+  service->GetDevices(&devices);
+
+  for (DeviceVector::iterator it = devices.begin(); it != devices.end();) {
+    if ((*it)->vendor_id() != vendor_id || (*it)->product_id() != product_id) {
+      it = devices.erase(it);
+    } else {
+      ++it;
+    }
+  }
+
+  for (size_t i = 0; i < devices.size(); ++i) {
+    result->Append(PopulateDevice(devices[i].get()));
+  }
+
+  SetResult(result.release());
+  AsyncWorkCompleted();
+}
+
+UsbRequestAccessFunction::UsbRequestAccessFunction() {}
+
+UsbRequestAccessFunction::~UsbRequestAccessFunction() {}
+
+bool UsbRequestAccessFunction::Prepare() {
+  parameters_ = RequestAccess::Params::Create(*args_);
+  EXTENSION_FUNCTION_VALIDATE(parameters_.get());
+  return true;
+}
+
+void UsbRequestAccessFunction::AsyncWorkStart() {
+#if defined(OS_CHROMEOS)
+  scoped_refptr<UsbDevice> device =
+      GetDeviceOrOrCompleteWithError(parameters_->device);
+  if (!device) return;
+
+  device->RequestUsbAcess(parameters_->interface_id,
+                          base::Bind(&UsbRequestAccessFunction::OnCompleted,
+                                     this));
+#else
+  SetResult(new base::FundamentalValue(false));
+  CompleteWithError(kErrorNotSupported);
+#endif  // OS_CHROMEOS
+}
+
+void UsbRequestAccessFunction::OnCompleted(bool success) {
+  SetResult(new base::FundamentalValue(success));
+  AsyncWorkCompleted();
+}
+
+UsbOpenDeviceFunction::UsbOpenDeviceFunction() {}
+
+UsbOpenDeviceFunction::~UsbOpenDeviceFunction() {}
+
+bool UsbOpenDeviceFunction::Prepare() {
+  parameters_ = OpenDevice::Params::Create(*args_);
+  EXTENSION_FUNCTION_VALIDATE(parameters_.get());
+  return true;
+}
+
+void UsbOpenDeviceFunction::AsyncWorkStart() {
+  scoped_refptr<UsbDevice> device =
+      GetDeviceOrOrCompleteWithError(parameters_->device);
+  if (!device) return;
+
+  handle_ = device->Open();
+  if (!handle_) {
+    SetError(kErrorOpen);
+    AsyncWorkCompleted();
+    return;
+  }
+
+  SetResult(PopulateConnectionHandle(
+      manager_->Add(new UsbDeviceResource(extension_->id(), handle_)),
+      handle_->device()->vendor_id(),
+      handle_->device()->product_id()));
   AsyncWorkCompleted();
 }
 
@@ -482,15 +713,12 @@ bool UsbListInterfacesFunction::Prepare() {
 }
 
 void UsbListInterfacesFunction::AsyncWorkStart() {
-  UsbDeviceResource* const resource = GetUsbDeviceResource(
-      parameters_->device.handle);
-  if (!resource) {
-    CompleteWithError(kErrorNoDevice);
-    return;
-  }
+  scoped_refptr<UsbDeviceHandle> device_handle =
+      GetDeviceHandleOrCompleteWithError(parameters_->handle);
+  if (!device_handle) return;
 
   scoped_refptr<UsbConfigDescriptor> config =
-      resource->device()->device()->ListInterfaces();
+      device_handle->device()->ListInterfaces();
 
   if (!config) {
     SetError(kErrorCannotListInterfaces);
@@ -560,7 +788,7 @@ void UsbListInterfacesFunction::AsyncWorkStart() {
 
 bool UsbListInterfacesFunction::ConvertDirectionSafely(
     const UsbEndpointDirection& input,
-    extensions::api::usb::Direction* output) {
+    usb::Direction* output) {
   const bool converted = ConvertDirectionToApi(input, output);
   if (!converted)
     SetError(kErrorConvertDirection);
@@ -569,7 +797,7 @@ bool UsbListInterfacesFunction::ConvertDirectionSafely(
 
 bool UsbListInterfacesFunction::ConvertSynchronizationTypeSafely(
     const UsbSynchronizationType& input,
-    extensions::api::usb::SynchronizationType* output) {
+    usb::SynchronizationType* output) {
   const bool converted = ConvertSynchronizationTypeToApi(input, output);
   if (!converted)
     SetError(kErrorConvertSynchronizationType);
@@ -578,7 +806,7 @@ bool UsbListInterfacesFunction::ConvertSynchronizationTypeSafely(
 
 bool UsbListInterfacesFunction::ConvertTransferTypeSafely(
     const UsbTransferType& input,
-    extensions::api::usb::TransferType* output) {
+    usb::TransferType* output) {
   const bool converted = ConvertTransferTypeToApi(input, output);
   if (!converted)
     SetError(kErrorConvertTransferType);
@@ -587,7 +815,7 @@ bool UsbListInterfacesFunction::ConvertTransferTypeSafely(
 
 bool UsbListInterfacesFunction::ConvertUsageTypeSafely(
     const UsbUsageType& input,
-    extensions::api::usb::UsageType* output) {
+    usb::UsageType* output) {
   const bool converted = ConvertUsageTypeToApi(input, output);
   if (!converted)
     SetError(kErrorConvertUsageType);
@@ -605,15 +833,12 @@ bool UsbCloseDeviceFunction::Prepare() {
 }
 
 void UsbCloseDeviceFunction::AsyncWorkStart() {
-  UsbDeviceResource* const resource = GetUsbDeviceResource(
-      parameters_->device.handle);
-  if (!resource) {
-    CompleteWithError(kErrorNoDevice);
-    return;
-  }
+  scoped_refptr<UsbDeviceHandle> device_handle =
+      GetDeviceHandleOrCompleteWithError(parameters_->handle);
+  if (!device_handle) return;
 
-  resource->device()->Close();
-  RemoveUsbDeviceResource(parameters_->device.handle);
+  device_handle->Close();
+  RemoveUsbDeviceResource(parameters_->handle.handle);
   AsyncWorkCompleted();
 }
 
@@ -628,15 +853,11 @@ bool UsbClaimInterfaceFunction::Prepare() {
 }
 
 void UsbClaimInterfaceFunction::AsyncWorkStart() {
-  UsbDeviceResource* resource =
-      GetUsbDeviceResource(parameters_->device.handle);
-  if (!resource) {
-    CompleteWithError(kErrorNoDevice);
-    return;
-  }
+  scoped_refptr<UsbDeviceHandle> device_handle =
+      GetDeviceHandleOrCompleteWithError(parameters_->handle);
+  if (!device_handle) return;
 
-  bool success =
-      resource->device()->ClaimInterface(parameters_->interface_number);
+  bool success = device_handle->ClaimInterface(parameters_->interface_number);
 
   if (!success)
     SetError(kErrorCannotClaimInterface);
@@ -654,14 +875,11 @@ bool UsbReleaseInterfaceFunction::Prepare() {
 }
 
 void UsbReleaseInterfaceFunction::AsyncWorkStart() {
-  UsbDeviceResource* resource =
-      GetUsbDeviceResource(parameters_->device.handle);
-  if (!resource) {
-    CompleteWithError(kErrorNoDevice);
-    return;
-  }
-  bool success =
-      resource->device()->ReleaseInterface(parameters_->interface_number);
+  scoped_refptr<UsbDeviceHandle> device_handle =
+      GetDeviceHandleOrCompleteWithError(parameters_->handle);
+  if (!device_handle) return;
+
+  bool success = device_handle->ReleaseInterface(parameters_->interface_number);
   if (!success)
     SetError(kErrorCannotReleaseInterface);
   AsyncWorkCompleted();
@@ -680,14 +898,11 @@ bool UsbSetInterfaceAlternateSettingFunction::Prepare() {
 }
 
 void UsbSetInterfaceAlternateSettingFunction::AsyncWorkStart() {
-  UsbDeviceResource* resource =
-      GetUsbDeviceResource(parameters_->device.handle);
-  if (!resource) {
-    CompleteWithError(kErrorNoDevice);
-    return;
-  }
+  scoped_refptr<UsbDeviceHandle> device_handle =
+      GetDeviceHandleOrCompleteWithError(parameters_->handle);
+  if (!device_handle) return;
 
-  bool success = resource->device()->SetInterfaceAlternateSetting(
+  bool success = device_handle->SetInterfaceAlternateSetting(
       parameters_->interface_number,
       parameters_->alternate_setting);
   if (!success)
@@ -707,12 +922,9 @@ bool UsbControlTransferFunction::Prepare() {
 }
 
 void UsbControlTransferFunction::AsyncWorkStart() {
-  UsbDeviceResource* const resource = GetUsbDeviceResource(
-      parameters_->device.handle);
-  if (!resource) {
-    CompleteWithError(kErrorNoDevice);
-    return;
-  }
+  scoped_refptr<UsbDeviceHandle> device_handle =
+      GetDeviceHandleOrCompleteWithError(parameters_->handle);
+  if (!device_handle) return;
 
   const ControlTransferInfo& transfer = parameters_->transfer_info;
 
@@ -740,7 +952,7 @@ void UsbControlTransferFunction::AsyncWorkStart() {
     return;
   }
 
-  resource->device()->ControlTransfer(
+  device_handle->ControlTransfer(
       direction,
       request_type,
       recipient,
@@ -764,12 +976,9 @@ bool UsbBulkTransferFunction::Prepare() {
 }
 
 void UsbBulkTransferFunction::AsyncWorkStart() {
-  UsbDeviceResource* const resource = GetUsbDeviceResource(
-      parameters_->device.handle);
-  if (!resource) {
-    CompleteWithError(kErrorNoDevice);
-    return;
-  }
+  scoped_refptr<UsbDeviceHandle> device_handle =
+      GetDeviceHandleOrCompleteWithError(parameters_->handle);
+  if (!device_handle) return;
 
   const GenericTransferInfo& transfer = parameters_->transfer_info;
 
@@ -793,13 +1002,13 @@ void UsbBulkTransferFunction::AsyncWorkStart() {
     return;
   }
 
-  resource->device()
-      ->BulkTransfer(direction,
-                     transfer.endpoint,
-                     buffer.get(),
-                     size,
-                     0,
-                     base::Bind(&UsbBulkTransferFunction::OnCompleted, this));
+  device_handle->BulkTransfer(
+      direction,
+      transfer.endpoint,
+      buffer.get(),
+      size,
+      0,
+      base::Bind(&UsbBulkTransferFunction::OnCompleted, this));
 }
 
 UsbInterruptTransferFunction::UsbInterruptTransferFunction() {}
@@ -813,12 +1022,9 @@ bool UsbInterruptTransferFunction::Prepare() {
 }
 
 void UsbInterruptTransferFunction::AsyncWorkStart() {
-  UsbDeviceResource* const resource = GetUsbDeviceResource(
-      parameters_->device.handle);
-  if (!resource) {
-    CompleteWithError(kErrorNoDevice);
-    return;
-  }
+  scoped_refptr<UsbDeviceHandle> device_handle =
+      GetDeviceHandleOrCompleteWithError(parameters_->handle);
+  if (!device_handle) return;
 
   const GenericTransferInfo& transfer = parameters_->transfer_info;
 
@@ -842,7 +1048,7 @@ void UsbInterruptTransferFunction::AsyncWorkStart() {
     return;
   }
 
-  resource->device()->InterruptTransfer(
+  device_handle->InterruptTransfer(
       direction,
       transfer.endpoint,
       buffer.get(),
@@ -862,12 +1068,9 @@ bool UsbIsochronousTransferFunction::Prepare() {
 }
 
 void UsbIsochronousTransferFunction::AsyncWorkStart() {
-  UsbDeviceResource* const resource = GetUsbDeviceResource(
-      parameters_->device.handle);
-  if (!resource) {
-    CompleteWithError(kErrorNoDevice);
-    return;
-  }
+  scoped_refptr<UsbDeviceHandle> device_handle =
+      GetDeviceHandleOrCompleteWithError(parameters_->handle);
+  if (!device_handle) return;
 
   const IsochronousTransferInfo& transfer = parameters_->transfer_info;
   const GenericTransferInfo& generic_transfer = transfer.transfer_info;
@@ -907,7 +1110,7 @@ void UsbIsochronousTransferFunction::AsyncWorkStart() {
     return;
   }
 
-  resource->device()->IsochronousTransfer(
+  device_handle->IsochronousTransfer(
       direction,
       generic_transfer.endpoint,
       buffer.get(),
@@ -929,28 +1132,19 @@ bool UsbResetDeviceFunction::Prepare() {
 }
 
 void UsbResetDeviceFunction::AsyncWorkStart() {
-  UsbDeviceResource* const resource = GetUsbDeviceResource(
-      parameters_->device.handle);
-  if (!resource) {
-    CompleteWithError(kErrorNoDevice);
-    return;
-  }
+  scoped_refptr<UsbDeviceHandle> device_handle =
+      GetDeviceHandleOrCompleteWithError(parameters_->handle);
+  if (!device_handle) return;
 
-  bool success = resource->device()->ResetDevice();
+  bool success = device_handle->ResetDevice();
   if (!success) {
-    UsbDeviceResource* const resource = GetUsbDeviceResource(
-        parameters_->device.handle);
-    if (!resource) {
-      CompleteWithError(kErrorNoDevice);
-      return;
-    }
-    resource->device()->Close();
-    RemoveUsbDeviceResource(parameters_->device.handle);
-    SetError(kErrorResetDevice);
+    device_handle->Close();
+    RemoveUsbDeviceResource(parameters_->handle.handle);
     SetResult(new base::FundamentalValue(false));
-    AsyncWorkCompleted();
+    CompleteWithError(kErrorResetDevice);
     return;
   }
+
   SetResult(new base::FundamentalValue(true));
   AsyncWorkCompleted();
 }