Re: [avrdude-dev] USB

[Joerg Wunsch]

As Russell Shaw wrote:

> Avrdude runs ok as root, but not as a normal user.

Sure, device permission problems.

> This returns -1 and i can't figure out why.

That's the way permission problems manifest under Linux: you can still
open the USB device in libusb (apparently, this is done through
something else than the actual device node), but it fails as soon as
you try sending a message to it (which is needed in order to request a
string descriptor entry from the device).

> Just to make sure of things, i also tried:
> 
> # chown -R root:avrdude /dev/usb*
> # chown -R root:avrdude /dev/bus/usb
> # chmod -R 660 /dev/usb*
> # chmod -R 660 /dev/bus/usb

Doesn't help.  All these devices are created by your system
dynamically.  As soon as you say "Goodbye!" to the AVRISPmkII, it
disconnects from and reconnects to the USB, and voila, you've got a
new /dev/bus/usb/... entry -- again with the wrong permissions.

Why do you insist on ignoring the udev hints that have been given to
you?

-- 
cheers, J"org               .-.-.   --... ...--   -.. .  DL8DTL

http://www.sax.de/~joerg/                        NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)