From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Date: Wed, 6 Jul 2016 10:42:44 +0200 From: Stefan Christ To: Guenter Roeck Cc: linux-watchdog@vger.kernel.org, linux-i2c@vger.kernel.org Subject: Re: [RFC 1/6] watchdog: da9063_wdt: don't trigger watchdog too fast Message-ID: <20160706084244.GA7031@lws-christ> References: <1467724943-13416-1-git-send-email-s.christ@phytec.de> <1467724943-13416-2-git-send-email-s.christ@phytec.de> <577BD34F.7000804@roeck-us.net> MIME-Version: 1.0 In-Reply-To: <577BD34F.7000804@roeck-us.net> Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable List-ID: Hi Guenter, On Tue, Jul 05, 2016 at 08:33:35AM -0700, Guenter Roeck wrote: > On 07/05/2016 06:22 AM, Stefan Christ wrote: > >Triggering the watchdog faster than T=5FWDMIN=3D256ms leads to resets of= the > >da9063 chip. The datasheet says that the watchdog must only be triggered > >in the timeframe T=5FWDMIN to T=5FWDMAX. The T=5FWDMAX is configured in = the > >driver. > > > >This problem was already mentioned in the patch: > > > > http://comments.gmane.org/gmane.linux.watchdog/1708 > > > >You also could say that this behavior is a feature. When the userspace > >goes wild, triggering the watchdog to fast, the system is reseted. But > >there is currently no information in the watchdog ABI to report a > >minimum wait time between two watchdog heartbeats. > > >=20 > There isn't ? What is the problem with min=5Fhw=5Fheartbeat=5Fms which was > introduced exactly for that purpose ? >=20 Ah your right. Sorry, I didn't noticed it. I'm sending a v2 patch for it. Thanks. Mit freundlichen Gr=C3=BC=C3=9Fen / Kind regards, Stefan Christ > Thanks, > Guenter >=20