>>>>> "Xiaofan" == Xiaofan Chen <xiaofanc@xxxxxxxxx> writes:
What about appended patch:
Unconditionally call usb_detach_kernel_driver. Check the return value only
later when other things fail, caused perhaps by missing permissions.
Bye
--
Uwe Bonnes bon@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Institut fuer Kernphysik Schlossgartenstrasse 9 64289 Darmstadt
--------- Tel. 06151 162516 -------- Fax. 06151 164321 ----------
>From f5fafd64ceb5db82417014d672f041b067472bf4 Mon Sep 17 00:00:00 2001
From: Uwe Bonnes <bon@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
Date: Tue, 18 May 2010 15:34:43 +0200
Subject: Unconditionally call libusb_detach_kernel_driver()
Try to be more helpfull when things fail because of missing permission
---
src/ftdi.c | 28 ++++++++++++++++++----------
1 files changed, 18 insertions(+), 10 deletions(-)
diff --git a/src/ftdi.c b/src/ftdi.c
index 5c25abd..7afd7c7 100644
--- a/src/ftdi.c
+++ b/src/ftdi.c
@@ -442,7 +442,7 @@ int ftdi_usb_open_dev(struct ftdi_context *ftdi,
libusb_device *dev)
{
struct libusb_device_descriptor desc;
struct libusb_config_descriptor *config0;
- int cfg, cfg0;
+ int cfg, cfg0, detach_errno;
if (ftdi == NULL)
ftdi_error_return(-8, "ftdi context invalid");
@@ -458,22 +458,16 @@ int ftdi_usb_open_dev(struct ftdi_context *ftdi,
libusb_device *dev)
cfg0 = config0->bConfigurationValue;
libusb_free_config_descriptor (config0);
-#ifdef LIBUSB_HAS_GET_DRIVER_NP
// Try to detach ftdi_sio kernel module.
- // Returns ENODATA if driver is not loaded.
//
// The return code is kept in a separate variable and only parsed
// if usb_set_configuration() or usb_claim_interface() fails as the
// detach operation might be denied and everything still works fine.
// Likely scenario is a static ftdi_sio kernel module.
- ret = libusb_detach_kernel_driver(ftdi->usb_dev, ftdi->interface);
- if (ret < 0 && ret != LIBUSB_ERROR_NOT_FOUND)
- ftdi_error_return(-11, "libusb_detach_kernel_driver () failed");
-#endif
+ detach_errno = libusb_detach_kernel_driver(ftdi->usb_dev, ftdi->interface);
if (libusb_get_configuration (ftdi->usb_dev, &cfg) < 0)
ftdi_error_return(-12, "libusb_get_configuration () failed");
-
// set configuration (needed especially for windows)
// tolerate EBUSY: one device with one configuration, but two interfaces
// and libftdi sessions to both interfaces (e.g. FT2232)
@@ -482,14 +476,28 @@ int ftdi_usb_open_dev(struct ftdi_context *ftdi,
libusb_device *dev)
if (libusb_set_configuration(ftdi->usb_dev, cfg0) < 0)
{
ftdi_usb_close_internal (ftdi);
- ftdi_error_return(-3, "unable to set usb configuration. Make sure
ftdi_sio is unloaded!");
+ if(detach_errno == EPERM)
+ {
+ ftdi_error_return(-8, "inappropriate permissions on device!");
+ }
+ else
+ {
+ ftdi_error_return(-3, "unable to set usb configuration. Make
sure ftdi_sio is unloaded!");
+ }
}
}
if (libusb_claim_interface(ftdi->usb_dev, ftdi->interface) < 0)
{
ftdi_usb_close_internal (ftdi);
- ftdi_error_return(-5, "unable to claim usb device. Make sure ftdi_sio
is unloaded!");
+ if(detach_errno == EPERM)
+ {
+ ftdi_error_return(-8, "inappropriate permissions on device!");
+ }
+ else
+ {
+ ftdi_error_return(-5, "unable to claim usb device. Make sure
ftdi_sio is unloaded!");
+ }
}
if (ftdi_usb_reset (ftdi) != 0)
--
1.6.4.2
--
libftdi - see http://www.intra2net.com/en/developer/libftdi for details.
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