Return-path: Received: from 007.netroom.de ([194.0.247.207]:17336 "EHLO 007.netroom.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932324AbZKDRlV (ORCPT ); Wed, 4 Nov 2009 12:41:21 -0500 Message-ID: <4AF1BCC3.8070205@draisberghof.de> Date: Wed, 04 Nov 2009 18:41:23 +0100 From: Josua Dietze MIME-Version: 1.0 To: Alan Stern CC: Johannes Berg , Frank Schaefer , USB list , linux-wireless@vger.kernel.org Subject: Re: [PATCH] ar9170usb: add mode-switching for AVM Fritz!WLAN USB N devices in cdrom mode References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: Alan Stern schrieb: > On Wed, 4 Nov 2009, Johannes Berg wrote: > >> I think you forgot to consider the case where both the driver and the >> mode switch code need an update to handle a new device. This is relevant >> in the case where a new device shows up that needs mode-switching, but >> even after switching has an ID that the current driver doesn't know >> about. > > This could be handled by programs like usb_modeswitch. The USB serial > drivers allow IDs to be added dynamically. > > Of course, if something more than that is required then the situation > would be different. However I think this is pretty rare. So far, mostly cdc_acm and high speed serial devices are known. There is the special case of the HSO interface for "Option" modems which resembles a network device IIRC. But switching them is pretty straightforward and driver support by the manufacturer seems to be OK. I don't know of any "switching" devices which are completely unsupported by the recent kernels. usb_modeswitch now has a wrapper which loads the "option" module by default if the "new" device will not be claimed by "cdc_acm", "hso" or "option". Using the "new_id" feature *any* ID can be used with it right away. Josua Dietze -- Man is the only creature on earth enabled to take a warm meal while flying! Loriot