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=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable 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 890F5C3A5A6 for ; Thu, 29 Aug 2019 15:29:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5A7622077B for ; Thu, 29 Aug 2019 15:29:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728068AbfH2P3E (ORCPT ); Thu, 29 Aug 2019 11:29:04 -0400 Received: from smtp1.de.adit-jv.com ([93.241.18.167]:34945 "EHLO smtp1.de.adit-jv.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728019AbfH2P3D (ORCPT ); Thu, 29 Aug 2019 11:29:03 -0400 Received: from localhost (smtp1.de.adit-jv.com [127.0.0.1]) by smtp1.de.adit-jv.com (Postfix) with ESMTP id A84943C0579; Thu, 29 Aug 2019 17:29:01 +0200 (CEST) Received: from smtp1.de.adit-jv.com ([127.0.0.1]) by localhost (smtp1.de.adit-jv.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id OgIdBam3RgzE; Thu, 29 Aug 2019 17:28:55 +0200 (CEST) Received: from HI2EXCH01.adit-jv.com (hi2exch01.adit-jv.com [10.72.92.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by smtp1.de.adit-jv.com (Postfix) with ESMTPS id 93CF43C04C0; Thu, 29 Aug 2019 17:28:55 +0200 (CEST) Received: from vmlxhi-102.adit-jv.com (10.72.93.184) by HI2EXCH01.adit-jv.com (10.72.92.24) with Microsoft SMTP Server (TLS) id 14.3.468.0; Thu, 29 Aug 2019 17:28:55 +0200 Date: Thu, 29 Aug 2019 17:28:52 +0200 From: Eugeniu Rosca To: "George G. Davis" CC: Shuah Khan , Jerry Hoemann , Colin Ian King , "open list:KERNEL SELFTEST FRAMEWORK" , open list , Eugeniu Rosca , Eugeniu Rosca Subject: Re: [PATCH] selftests: watchdog: Add optional file argument Message-ID: <20190829152852.GA15203@vmlxhi-102.adit-jv.com> References: <1567053566-18971-1-git-send-email-george_davis@mentor.com> <20190829143814.GA3424@vmlxhi-102.adit-jv.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20190829143814.GA3424@vmlxhi-102.adit-jv.com> User-Agent: Mutt/1.12.1+40 (7f8642d4ee82) (2019-06-28) X-Originating-IP: [10.72.93.184] Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 29, 2019 at 04:38:14PM +0200, Eugeniu Rosca wrote: > Hi George, > > On Thu, Aug 29, 2019 at 12:39:25AM -0400, George G. Davis wrote: > > Some systems have multiple watchdog devices where the first device > > registered is assigned to the /dev/watchdog device file. > > Confirmed on R-Car H3-Salvator-X: > > root@rcar-gen3:~# ls -al /dev/watchdog* > crw------- 1 root root 10, 130 Aug 21 09:38 /dev/watchdog > crw------- 1 root root 247, 0 Aug 21 09:38 /dev/watchdog0 Based on [1], I think this patch is actually helpful when there is at least a /dev/watchdog1 in the system. Particularly on R-Car3, this happens when enabling softdog in addition to the standard RWDT: root@rcar-gen3:~# ls -al /dev/watchdog* crw------- 1 root root 10, 130 Aug 21 09:38 /dev/watchdog crw------- 1 root root 247, 0 Aug 21 09:38 /dev/watchdog0 crw------- 1 root root 247, 1 Aug 21 09:38 /dev/watchdog1 [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/watchdog/watchdog-kernel-api.rst?h=v5.3-rc6#n71 ----8<---- id 0 is special. It has both a /dev/watchdog0 cdev (dynamic major, minor 0) as well as the old /dev/watchdog miscdev. ----8<---- -- Best Regards, Eugeniu.