From 429d808d4e72e57bbd437991d75d15a19ce7d715 Mon Sep 17 00:00:00 2001
From: Ingo Ruhnke <grumbel@gmx.de>
Date: Thu, 26 May 2011 15:03:34 +0200
Subject: [PATCH] Added try_detach to USBInterface
---
src/usb_interface.cpp | 27 +++++++++++++++++++++++++--
src/usb_interface.hpp | 2 +-
2 files changed, 26 insertions(+), 3 deletions(-)
diff --git a/src/usb_interface.cpp b/src/usb_interface.cpp
index 1f174f3..e7ed5f8 100644
--- a/src/usb_interface.cpp
+++ b/src/usb_interface.cpp
@@ -53,13 +53,36 @@ private:
USBWriteCallback& operator=(const USBWriteCallback&);
};
-USBInterface::USBInterface(libusb_device_handle* handle, int interface) :
+USBInterface::USBInterface(libusb_device_handle* handle, int interface, bool try_detach) :
m_handle(handle),
m_interface(interface),
m_endpoints()
{
int ret = libusb_claim_interface(handle, m_interface);
- if (ret != LIBUSB_SUCCESS)
+ if (ret == LIBUSB_SUCCESS)
+ {
+ // success
+ }
+ else if (ret == LIBUSB_ERROR_BUSY && try_detach)
+ {
+ // try to detach and then try to reopen
+ ret = libusb_detach_kernel_driver(handle, interface);
+ if (ret != LIBUSB_SUCCESS)
+ {
+ raise_exception(std::runtime_error, "error detaching kernel driver: "
+ << interface << ": " << usb_strerror(ret));
+ }
+ else
+ {
+ // kernel driver detached, try to claim it again
+ ret = libusb_claim_interface(handle, interface);
+ if (ret != LIBUSB_SUCCESS)
+ {
+ raise_exception(std::runtime_error, "error claiming interface: " << interface << ": " << usb_strerror(ret));
+ }
+ }
+ }
+ else
{
raise_exception(std::runtime_error, "error claiming interface: " << interface << ": " << usb_strerror(ret));
}
diff --git a/src/usb_interface.hpp b/src/usb_interface.hpp
index 09b06df..2dd83b3 100644
--- a/src/usb_interface.hpp
+++ b/src/usb_interface.hpp
@@ -35,7 +35,7 @@ private:
Endpoints m_endpoints;
public:
- USBInterface(libusb_device_handle* handle, int interface);
+ USBInterface(libusb_device_handle* handle, int interface, bool try_detach = false);
~USBInterface();
void submit_read(int endpoint, int len,