Re: "Resource Temporarily Unavailable" error opening device file beginning with linux kernel 2.6.37.1

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]


On Wed, Jun 20, 2012 at 05:38:44PM -0500, Donald Kayser wrote:
> Hello,
> 
> I develop linux drivers for an embedded system with USB devices. The
> USB drivers in question have been stable for a while, at least since
> linux 2.6.26.n.

Nice.  Any reason why they aren't in the main kernel.org tree?

> We have to move the system to the newest 2.6 kernel
> (2.6.39.4) that has support for video hardware. When I built the
> embedded system's USB drivers for the 2.6.39.4 kernel, I keep
> getting the error message "Resource Temporarily Unavailable" when
> attempting to 'cat' the device file. No error message appear in the
> syslog. My USB driver uses the same kind of calls as usb-skeleton.c
> to create the device file via usb_register() in the init function
> and usb_register_dev() in the probe callback. The device is create
> with a dynamic minor number in its name in /dev as expected. But
> every use of this file comes back with the error. My debug printk
> indicate my open function is not ever being called.

Can you run 'git bisect' to track down the offending patch?  2.6.39 was
years ago, I can't remember what happened in the kernel tree one month
ago...

> I checked the difference between usb-skeleton.c files and there has
> only been an addition of adding a llseek entry in the file
> operations structure. I modified my driver and it didn't make a
> difference - long shot.

I wouldn't trust the usb-skeleton.c to have been kept up to date.

> I tested kernels 2.6.39.4, 2.6.38.8, 2.6.37.7, 2.6.37.1, 2.6.36.4.
> It works in kernels before and including 2.6.36.4. It stops working
> for all kernels tested beyond and including 2.6.37.1.

That gives you a good start to run 'git bisect' on.

thanks,

greg k-h
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


B and H Foto and Electronics Corp.

[Linux Media]     [Video for Linux]     [Linux Input]     [Linux Audio Users]     [Photo]     [Yosemite News]    [Yosemite Photos]    [Free Online Dating]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]     [More Archives]

Add to Google Powered by Linux