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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 BFFE0C433B4 for ; Mon, 17 May 2021 17:12:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9DDEE6128A for ; Mon, 17 May 2021 17:12:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236044AbhEQRON (ORCPT ); Mon, 17 May 2021 13:14:13 -0400 Received: from mta-02.yadro.com ([89.207.88.252]:50964 "EHLO mta-01.yadro.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S243316AbhEQROK (ORCPT ); Mon, 17 May 2021 13:14:10 -0400 Received: from localhost (unknown [127.0.0.1]) by mta-01.yadro.com (Postfix) with ESMTP id 370E541370; Mon, 17 May 2021 17:12:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=yadro.com; h= content-transfer-encoding:mime-version:user-agent:content-type :content-type:organization:references:in-reply-to:date:date:from :from:subject:subject:message-id:received:received:received; s= mta-01; t=1621271570; x=1623085971; bh=yk9EC+Dve1pamEtbvjpjbU1uw Oxf7cDLNNgPjnJ+aDs=; b=eZ7Z2RRNqXGEHeDei3cSHutMBxCxQz6+J9MLIYwI0 VadwEH4iVup8LD2PLNo3DSPrh4nP1Sa+rMH5TjMejtDYdNCTJM1f4RYuPX5inWKz W/nAVSKemIWYdu4I7bYJAZtyMFvMBQk/bfqhFKLLLIAnuoHag+432eZPROhdQmlF gU= X-Virus-Scanned: amavisd-new at yadro.com Received: from mta-01.yadro.com ([127.0.0.1]) by localhost (mta-01.yadro.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id He7ny6xBWzgN; Mon, 17 May 2021 20:12:50 +0300 (MSK) Received: from T-EXCH-03.corp.yadro.com (t-exch-03.corp.yadro.com [172.17.100.103]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mta-01.yadro.com (Postfix) with ESMTPS id 835F241384; Mon, 17 May 2021 19:59:49 +0300 (MSK) Received: from localhost.localdomain (10.199.0.36) by T-EXCH-03.corp.yadro.com (172.17.100.103) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384_P384) id 15.1.669.32; Mon, 17 May 2021 19:59:49 +0300 Message-ID: Subject: Re: [PATCH 4/4] hwmon: vcnl3020: add hwmon driver for intrusion sensor From: Ivan Mikhaylov To: Guenter Roeck CC: Jonathan Cameron , Lars-Peter Clausen , Peter Meerwald-Stadler , "Jean Delvare" , , , Date: Mon, 17 May 2021 20:08:24 +0300 In-Reply-To: <20210505140208.GA1913659@roeck-us.net> References: <20210430152419.261757-1-i.mikhaylov@yadro.com> <20210430152419.261757-5-i.mikhaylov@yadro.com> <20210430163831.GA3163069@roeck-us.net> <8dbdf071f9f2041b92cabfa417487a3ec3e9647e.camel@yadro.com> <20210505140208.GA1913659@roeck-us.net> Organization: YADRO Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.5 (3.36.5-2.fc32) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Originating-IP: [10.199.0.36] X-ClientProxiedBy: T-EXCH-01.corp.yadro.com (172.17.10.101) To T-EXCH-03.corp.yadro.com (172.17.100.103) Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org On Wed, 2021-05-05 at 07:02 -0700, Guenter Roeck wrote: > On Tue, May 04, 2021 at 10:46:53PM +0300, Ivan Mikhaylov wrote: > > On Fri, 2021-04-30 at 09:38 -0700, Guenter Roeck wrote: > > > On Fri, Apr 30, 2021 at 06:24:19PM +0300, Ivan Mikhaylov wrote: > > > > Intrusion status detection via Interrupt Status Register. > > > > > > > > Signed-off-by: Ivan Mikhaylov > > > > > > I think this should, if at all, be handled using the > > > iio->hwmon bridge (or, in other words, require a solution > > > which is not chip specific). > > > > Thanks a lot for suggestion, it's actually looks what's needed here instead > > of > > this driver. Anyways, there is no IIO_PROXIMITY support inside supported > > types > > in iio_hwmon.c. Should I add additional case inside this driver for > > IIO_PROXIMITY type? > > > > > I am also not sure if "proximity" is really appropriate to use > > > for intrusion detection in the sense of hardware monitoring. > > > This would require a proximity sensor within a chassis, which > > > would be both overkill and unlikely to happen in the real world. > > > "Intrusion", in hardware monitoring context, means "someone > > > opened the chassis", not "someone got [too] close". > > > > > > > I'm not sure either but it exists :) And it's exactly for this purpose: > > "someone opened the chassis", "how near/far is cover?". > > > > The cost for VCNL3020, for a full reel with 3,300 chips, is $1.17 per chip > at Mouser. A mechanical switch costs a couple of cents. A single proximity > sensor won't cover all parts of a chassis; one would likely need several > chips to be sure that are no blind spots (if that is even possible - I don't > think it is in any of my PC chassis due to mechanical limitations). This > is on top of programming, which would be sensitive to generating false > alarms (or missing alarms, for that matter). That sounds quite impractical > and expensive to me. I'd really like to see the actual use case where a > proximity sensor (or set of proximity sensors) is used for intrusion > detection in the sense of hardware monitoring - not just the technical > possibility of doing so, but an actual use case (as in "this vendor, > in this chassis, is doing it"). > > Thanks, > Guenter Guenter, VCNL3020 is indeed used as an intrusion detection sensor at least in one real design. That is YADRO VESNIN Rev. C where the proximity sensor is installed in a very tight space on an nvme switch board where installation of a mechanical switch was not possible without substantial redesign of the existing other components that would cost a lot more than the price of VCNL3020. VESNIN is a very tight-packed design of 4 x POWER8 CPUs, up to 8TB of RAM, and 26 nvme disks, all that in just 2U. * https://imgur.com/a/wU9wEd4