Re: [Libusb-devel] Patch: libusb/os/linux_usbfs.c: Distingush between usbfs and other kernel mode drivers

[Michael P. <mic...@gm...>]

Xiaofan Chen wrote:
>>
http://libusb.sourceforge.net/api-1.0/group__dev.html#ga76e047ca95da2b32d0e7
455da1804a49
>> libusb_kernel_driver_active ()
>>     0 if no kernel driver is active
>>     1 if a kernel driver is active
>>     LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
>>     another LIBUSB_ERROR code on other failure
>>
>> Uwe's patch add a 2 as the return value to inform the user
>> that "usbfs" is the current bound driver. Then the user can
>> decide to proceed with the driver detaching or not. Typically
>> the user should decide not to do so, but he can do that if
>> he really wants to do that.

Or you could add another api called "libusb_usbfs_kernel_driver_active ()",
or perhaps one that returns the driver name.  At least this would allow us
not to change an existing api, if that's your concern.

But I think there is not a perfect solution without some help from the
kernel.  Maybe not as drastic as changing whether or not usbfs can detach,
though that sounds simpler to implement than taking a string that says which
driver not to detach.  Perhaps the latter, while more complicated, could be
more backward compatible?  I don't know.

Michael