Re: [RFC][PATCH] p54usb: rewriting rx/tx routines to make use ofusb_anchor's facilities

From: Larry Finger
Date: Sat Dec 06 2008 - 16:47:53 EST

Christian Lamparter wrote:
> Alan, I've got a question about:
> "Create and initialize a usb_anchor structure, and each time you create
> a new URB, call usb_anchor_urb(). Then you can free the URB as soon as
> it is submitted; the anchor will keep it pinned until it completes, and
> it is automatically removed from the anchor when the completion routine
> is called."
> Do we have to call usb_free_urb again, if we're resubmitting the urb in the
> complete callback? (the code what I'm referring to is p54u_rx_cb in p54usb.c)

I am very interested in the answer to this question. My interpretation is that
you cannot resubmit the urb after it has been posted to usb_anchor_usb() because
the USB core will have deleted it, and that the callback routine will have to
allocate a new urb, anchor it, and then free it as well.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at