Alan Stern wrote: > On Tue, 3 Feb 2009, David Vrabel wrote: > >>> Ah, but you're forgetting the possibile cases in which the controller >>> doesn't support DMA. >> I don't think it's useful to speculate on possible hardware. If >> hardware like this is produced then we can revisit this. > > What do you mean? Of course hardware like this exists, and Linux > contains drivers for it. Otherwise there would be no reason for the > code to be written the way it is. Too clarify, there is no hardware that a) supports scatter-gather in hardware and b) doesn't support DMA at all times. Anyway, the sensible thing to do is for usbcore to /not/ map the scatterlist and leave that up to the HCD. David -- David Vrabel, Senior Software Engineer, Drivers CSR, Churchill House, Cambridge Business Park, Tel: +44 (0)1223 692562 Cowley Road, Cambridge, CB4 0WZ http://www.csr.com/ -- 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
