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

[Xiaofan C. <xia...@gm...>]

On Thu, Oct 7, 2010 at 12:02 AM, Alan Stern <st...@ro...> wrote:
> On Wed, 6 Oct 2010, Xiaofan Chen wrote:
>> If the Linux kernel USB developer like Alan Stern or Greg KH
>> say so, I would be convinced.
>
> This probably doesn't matter any more, but for the record, Peter is
> right.  usbfs really is a kernel driver.  A slightly peculiar one, to
> be sure, because it doesn't take any action on its own -- it merely
> relays requests from userspace.  Nevertheless, it is treated just like
> any other kernel driver.

Thanks. Now I am really really convinced. ;-)

>> If there is a kernel driver attached to the USB device (an interface),
>> then libusb_claim_interface() should fail. And this is consistent
>> with my view that "usbfs" is not a kernel driver in the context
>> of libusb.
>
> If another program has claimed an interface, then
> libusb_claim_interface() _will_ fail.

Yes this makes sense now.


-- 
Xiaofan