Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758010AbYFYOZF (ORCPT ); Wed, 25 Jun 2008 10:25:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755182AbYFYOYy (ORCPT ); Wed, 25 Jun 2008 10:24:54 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:56830 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752726AbYFYOYy (ORCPT ); Wed, 25 Jun 2008 10:24:54 -0400 Date: Wed, 25 Jun 2008 10:24:53 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: "Perez-Gonzalez, Inaky" cc: David Vrabel , Kernel development list , AntonioLin , Subject: RE: Scatter-gather list constraints In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1055 Lines: 31 On Tue, 24 Jun 2008, Perez-Gonzalez, Inaky wrote: > >From: David Vrabel [mailto:david.vrabel@csr.com] > > > >> That would be ideal. However there is no way to pass an S-G list > along > >> with an URB; there's no field for it in the data structure. And none > >> of the existing host controller drivers support such a thing. > >> > >> I suppose we could add a field to struct urb and add a flag > indicating > >> whether the controller driver supports S-G lists. > > > >This is what I was thinking. > > That would simplify a *LOT* of WUSB wire-adapter code which now is a > horrible kludge. In what way would it simplify the code? Note that usbcore already contains a scatter-gather library. (Unfortunately the library is limited in usefulness because it needs to run in process context.) Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/