From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f65.google.com ([74.125.83.65]:46439 "EHLO mail-pg0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752863AbeEPM4k (ORCPT ); Wed, 16 May 2018 08:56:40 -0400 Received: by mail-pg0-f65.google.com with SMTP id u8-v6so254231pgp.13 for ; Wed, 16 May 2018 05:56:40 -0700 (PDT) Subject: Re: [PATCH v2] watchdog: da9063: Fix setting/changing timeout To: Marco Felsch , Steve Twiss , Guenter Roeck Cc: "wim@linux-watchdog.org" , Support Opensource , "fzuuzf@googlemail.com" , Guenter Roeck , "kernel@pengutronix.de" , "linux-watchdog@vger.kernel.org" References: <20180509123243.21170-1-m.felsch@pengutronix.de> <6ED8E3B22081A4459DAC7699F3695FB7019417EA41@SW-EX-MBX02.diasemi.com> <20180515184412.GC16006@roeck-us.net> <6ED8E3B22081A4459DAC7699F3695FB7019418108B@SW-EX-MBX02.diasemi.com> <20180516090129.qozynkc4cb523nru@pengutronix.de> From: Guenter Roeck Message-ID: <607ce4db-891f-5eaf-3832-216bac7f94b2@roeck-us.net> Date: Wed, 16 May 2018 05:56:36 -0700 MIME-Version: 1.0 In-Reply-To: <20180516090129.qozynkc4cb523nru@pengutronix.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-watchdog-owner@vger.kernel.org List-Id: linux-watchdog@vger.kernel.org On 05/16/2018 02:01 AM, Marco Felsch wrote: > Hi Steve and Guenter, > > On Wed, May 16, 2018 at 07:35:13AM +0000, Steve Twiss wrote: >> On 15 May 2018 19:44, Guenter Roeck wrote, >> >>> Subject: Re: [PATCH v2] watchdog: da9063: Fix setting/changing timeout >>> >>> On Wed, May 09, 2018 at 04:10:15PM +0200, Marco Felsch wrote: >>>> Hi Steve, >>>> >>>> >>>> That would be great looking forward to hear from you. I will prepare a v3 if it is. >>>> >>> Any updates ? >>> >>> Guenter >> Hi Guenter and Marco, >> >> Thank you for your patience. >> The best advice I can give at the moment is: >> >> Please follow what has been done in the DA9062 and DA9053 device drivers. >> https://elixir.bootlin.com/linux/latest/source/drivers/watchdog/da9062_wdt.c#L90 >> https://elixir.bootlin.com/linux/latest/source/drivers/watchdog/da9052_wdt.c#L76 >> >> In these cases: >> "setting TWDSCALE to zero for at least 150 us before writing the new value" > Okay. I tested it without a delay and saw no issues but I will add the > delay to be on the safe side. > Is that okay for you Guenter? Yes. Better safe than sorry. Thanks, Guenter >> There will be a longer answer, but that must wait until the formal datasheets have >> been clarified by the hardware engineers. >> >> Regards, >> Steve >> > Regards, > Marco >