From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AE034C433ED for ; Thu, 8 Apr 2021 10:11:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 647D26115B for ; Thu, 8 Apr 2021 10:11:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230412AbhDHKLM (ORCPT ); Thu, 8 Apr 2021 06:11:12 -0400 Received: from mx2.suse.de ([195.135.220.15]:52758 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229517AbhDHKLM (ORCPT ); Thu, 8 Apr 2021 06:11:12 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1617876660; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ungriHiX5fEUPDsMxDg6ldWqj8gfMRUm2LRwontY2qo=; b=stwSvQVHWURq+vF8p7oLTd/SCbf3kRN3L6USW3KVD73irNdO8on2X9pIdoK2339hUFUITX kk1kL7OlsmKFmMBLhz6hyx16Gy8P+4+z7OMz3mnKDlEgh4kthKW7fsiHHe9kppmJBbV7lR lhy+30fF03B/Odu13ZOhxyrqTKb6Lg4= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 1ABCAAFCC; Thu, 8 Apr 2021 10:11:00 +0000 (UTC) Message-ID: <2c67dd97bbdc81369eb297fdb7ac58616110fb77.camel@suse.com> Subject: Re: [PATCH 3/4] USB: serial: add support for multi-interface functions From: Oliver Neukum To: Johan Hovold Cc: Mauro Carvalho Chehab , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Date: Thu, 08 Apr 2021 12:10:48 +0200 In-Reply-To: References: <20210330143820.9103-1-johan@kernel.org> <20210330143820.9103-4-johan@kernel.org> <3ae68552f3c689c23cbf2573772239c00e2c94be.camel@suse.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.34.4 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Am Donnerstag, den 01.04.2021, 09:46 +0200 schrieb Johan Hovold: > On Wed, Mar 31, 2021 at 01:21:15PM +0200, Oliver Neukum wrote: > > Am Mittwoch, den 31.03.2021, 09:08 +0200 schrieb Oliver Neukum: > > on the third hand, the more I look at this, would you mind putting > > sibling_release() with a modified name into usbcore? This functionality > > is not limited to serial drivers. btusb needs it; cdc-acm needs it; > > usbaudio neds it. We have code duplication. > > Tell me about it. ;) Unfortunately, drivers all tend to handle this > slightly different, for example, using a disconnected flag, some claim > more than one other interface, others look like they may be using their > interface data as a flag for other purposes, etc. > > At some point we could unify all this but until then I don't think > putting only half of an interface into core makes much sense. OK, very well, then let's look at this from a fundamental point and design a bit. First, can we disregard the case of more than two interfaces? Regards Oliver