On Thu, 12 Apr 2007, Danny Budik wrote:
> Is it possible to read the frame number field that the USB host
> controller is currently sending to a usb device from a user space
> program? I am using ioctl functions and the structures in
> usbdevice_fs.h to set, claim and release the interface, as well as to
> do bulk transfers.
There is no direct way to do it.
Under some circumstances there is an indirect way. If you build your
kernel with CONFIG_USB_DEBUG then for EHCI and OHCI controllers you should
be able to find the current frame number in
/sys/class/usb_host/usb_hostN/registers
where N is the bus number. If you also set CONFIG_DEBUG_FS and mount a
debugfs filesystem, then for UHCI controllers you will find the frame
number for each controller in the uhci/ subdirectory of the debugfs
filesystem.
Obviously these methods are rather crude and aren't meant for regular use.
In any case, you wouldn't be able to depend very heavily on the frame
numbers you get. By the time your program finished reading them, they
could well have changed.
Alan Stern
-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys-and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
_______________________________________________
[EMAIL PROTECTED]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
