struct usb_config: pass custom parameter to callback?

Hans Petter Selasky hselasky at
Fri Nov 12 15:25:34 UTC 2010

On Friday 12 November 2010 16:01:44 Lev Serebryakov wrote:
> Hello, Freebsd-usb.
>   Is it possible to pass custom parameter to xfer callback, configured
> via "struct usb_config"?
>   I'm writing driver for device, which have multiple equivalent ports,
>   each whith its own paor of pipes (for IN and OUT), and I want to use
>   only   two   callbacks.   Is  it  possible? Or should I make N pairs
>   of almost-the-same thunk functions?


There is usbd_xfer_get/set_priv() and usbd_xfer_softc() which you can use to 
get and set private and softc alike structure pointers after that the USB 
transfers are setup. Any more custom parameters you need wrap using callback 


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