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=-5.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 B7748C43465 for ; Mon, 21 Sep 2020 12:03:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7278B216C4 for ; Mon, 21 Sep 2020 12:03:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600689792; bh=sBDvdw5RZAREDMyNV1FqrenP4gOZwo6GSutvf36Vse4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=zo6MtJyuq1R3k4o+KyhxC4DIhdGoliaaG7sffp8ouq2UpkYNgj2f2h4HiEhp+Ir/s 628KJ63uPzI4UUeLu+tYmYpkon/TMPOXrjHUb86MhzZ1xZa3xlg8gUUX/ILurMiLt4 xfxP0rNySmIVwGPg2xmviiRKe7dqvu+4Iq9T7CGE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726853AbgIUMDL (ORCPT ); Mon, 21 Sep 2020 08:03:11 -0400 Received: from mail-lf1-f44.google.com ([209.85.167.44]:39172 "EHLO mail-lf1-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726413AbgIUMDL (ORCPT ); Mon, 21 Sep 2020 08:03:11 -0400 Received: by mail-lf1-f44.google.com with SMTP id q8so13692245lfb.6; Mon, 21 Sep 2020 05:03:10 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=+QI8mTIy0Eft8z2TjdteLwGuaZdvxggWE9Qg6IcauVw=; b=fTTEuQpRQiYen3wlgkU38kPA3n4KBCjf/9KVJ9ocl8kj3UoSfimhsYdYVqCMMR64Vo PXwkoiX6KrvRUCfwOGeufZQGWwbX/nC2VoKvx47DMRalTijpeaR0i0YoP4scoByUqj73 ITcMeTFfpZlV7shY5IL99XOXx2DRXSe4Uh0KPqdfIDFR+pZLTPQq99nszGYH9B5cDI6Z +p7rV28zbuH1LtZHQL8voSSGmOKqsqf2jUM/1PcpaHqy8eLbsotw2YldbJtsgLoKDRdR d8nm0G4fhPvtlv5IaHTpok/vq3vY+/I6OBISy+zgE90vaPvTXOKELXt/xegIX4q7i7op g3DA== X-Gm-Message-State: AOAM531GubAorwxQDLz0bGfklVsXYm5jprlpEFhRGZOKONTimubunuI0 OjYCIwxMoW8KyFvV8bgD5Jw= X-Google-Smtp-Source: ABdhPJxdjtM6vpjl17ORbFrP8CgY69mUCFUTz49xDT59p6xw6fjC7zTUkILj4y0C1vObC+RLgxP+4A== X-Received: by 2002:a19:4e:: with SMTP id 75mr14633741lfa.159.1600689789491; Mon, 21 Sep 2020 05:03:09 -0700 (PDT) Received: from xi.terra (c-beaee455.07-184-6d6c6d4.bbcust.telenor.se. [85.228.174.190]) by smtp.gmail.com with ESMTPSA id n2sm2667943lji.97.2020.09.21.05.03.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Sep 2020 05:03:08 -0700 (PDT) Received: from johan by xi.terra with local (Exim 4.93.0.4) (envelope-from ) id 1kKKX8-0000WD-Av; Mon, 21 Sep 2020 14:03:02 +0200 Date: Mon, 21 Sep 2020 14:03:02 +0200 From: Johan Hovold To: Oliver Neukum Cc: Johan Hovold , Greg Kroah-Hartman , linux-usb@vger.kernel.org, Daniel Caujolle-Bert , stable@vger.kernel.org Subject: Re: [PATCH v2] USB: cdc-acm: add Whistler radio scanners TRX series support Message-ID: <20200921120302.GU24441@localhost> References: <20200921081022.6881-1-johan@kernel.org> <1600677792.2424.61.camel@suse.com> <20200921093145.GS24441@localhost> <1600684156.2424.65.camel@suse.com> <20200921113601.GT24441@localhost> <1600688954.2424.76.camel@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1600688954.2424.76.camel@suse.com> Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Mon, Sep 21, 2020 at 01:49:14PM +0200, Oliver Neukum wrote: > Am Montag, den 21.09.2020, 13:36 +0200 schrieb Johan Hovold: > > On Mon, Sep 21, 2020 at 12:29:16PM +0200, Oliver Neukum wrote: > > Hi, > > > I meant that instead of falling back to "combined-interface" probing we > > could assume that all interfaces with three endpoints are "combined" and > > simply ignore the union and call managementy. descriptors and all the ways > > that devices may have gotten those wrong. > > I am afraid we would break the spec. I cannot recall a prohibition on > having more endpoints than necessary. Heuristics and ignoring invalid > descriptors is one things. Ignoring valid descriptors is something > else. That depends on how you read the spec (see "3.3.1 Communication Class Interface"). But sure, it's probably be better to err on the safe-side. > > I was thinking more of the individual entries in the device-id table > > whose control interfaces may not even be of the Communication class. But > > hopefully that was verified when adding them. > > Now you are confusing me. In case of a quirky device, why change > the current logic? Just because they have a quirk defined, doesn't mean they don't rely on the generic probe algorithm (e.g. a USB_DEVICE entry which matches all interface classes and only specifies SEND_ZERO_PACKET). Johan