Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933133AbbKMS2M (ORCPT ); Fri, 13 Nov 2015 13:28:12 -0500 Received: from bh-25.webhostbox.net ([208.91.199.152]:48877 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932846AbbKMS2K (ORCPT ); Fri, 13 Nov 2015 13:28:10 -0500 Subject: Re: [RESEND][PATCH] watchdog: add support for Sigma Designs SMP86xx To: =?UTF-8?B?TcOlbnMgUnVsbGfDpXJk?= References: <1447420459-5301-1-git-send-email-mans@mansr.com> <56461155.80808@roeck-us.net> <5646240C.5070105@roeck-us.net> Cc: Wim Van Sebroeck , linux-kernel@vger.kernel.org, linux-watchdog@vger.kernel.org From: Guenter Roeck Message-ID: <56462BB7.9000709@roeck-us.net> Date: Fri, 13 Nov 2015 10:28:07 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 8bit X-Authenticated_sender: linux@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: linux@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1548 Lines: 33 On 11/13/2015 10:02 AM, M?ns Rullg?rd wrote: >>>>> +static const struct of_device_id tangox_wdt_dt_ids[] = { >>>>> + { .compatible = "sigma,smp8642-wdt" }, >>>> >>>> So this is really for smp8642 only, not for any other chips in the series ? >>> >>> It's for about a dozen SMP86xx, SMP87xx, and SMP89xx chips. Should I >>> list them all? I don't even know where to find a comprehensive list of >>> device numbers. >>> >> I thought so, but I am not a devicetree expert, and I see some "xx" in >> existing devicetree bindings. Something to ask when you submit the >> bindings to the devicetree mailing list. Either case, I think it would >> be either something like "sigma,smp86xx-wdt" or a list of all of them, >> but not "sigma,smp8642-wdt" to be used for all chips. > > The general advice is to not use wildcards in DT bindings since the next > chip matching the pattern might not be compatible at all. New chips > known to be compatible with an old one can specify both the exact chip > and the older one such that existing drivers will work automatically. > If at some point they are found not to be compatible after all (hardware > bugs, perhaps) a fixed driver will work with existing device trees. > So I think the best approach here would be to list the chips known to work. Thanks, Guenter -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/