Re: libusb device search problem

[Robert Hubley <rhubley@xxxxxxxxxxxxxxxxxx>]

 Thanks for the feedback.  For the record, I am not submitting a 
bug...but rather a helpful google searchable solution to a legacy 
problem.  As many of us embedded programmers are dealing with 2.4 and 
early 2.6 kernels on this type of info is golden when you don't have an 
option to upgrade.  Perhaps when I have much much more time I will look 
into why /dev/bus/usb is not being populated.  Nah...I will just go on 
vacation if I ever get that time. :-)
-R

On 9/29/10 4:16 PM, Xiaofan Chen wrote:
> On Thu, Sep 30, 2010 at 6:23 AM, Robert Hubley
> <rhubley@xxxxxxxxxxxxxxxxxx>  wrote:
> >   Heads up.  While tracking down a problem with libftdi not seeing my clearly
> > attached USB device.  I found a potential problem with the way libusb
> > searches for USB devices under the linux OS.  It uses a priority search
> > starting with an environment variable followed by the /dev/bus/usb hierarchy
> > and then the /proc/bus/usb hierarchy.  On my particular Debian system it
> > looks like /dev/bus/usb is only partially populated with devices ( perhaps
> > the ones supported by kernel drivers??? ), while /proc/bus/usb contains a
> > dynamic list of all the devices.  I solved the problem by reversing the
> > order of this search ( /proc/bus/usb first ).  Not a problem with libftdi
> > per se...but I wanted to put this up somewhere in case anyone else was
> > banging their heads over this.
> I guess you are using libftdi-0.1x and libusb-0.1 under Debian.
> Just take note libusb-0.1 is not maintained any more and
> all the tickers submitted got a "wontfix" solution.
> http://www.libusb.org/report/9
>
> And /proc/bus/usb is not available for most of the modern
> distros.
>
> And the proper fix is try to figure out why the  /dev/bus/usb is
> only partially populated in your particular distro.

--
libftdi - see http://www.intra2net.com/en/developer/libftdi for details.
To unsubscribe send a mail to libftdi+unsubscribe@xxxxxxxxxxxxxxxxxxxxxxx