From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guenter Roeck Subject: Re: [RFC 1/6] watchdog: da9063_wdt: don't trigger watchdog too fast Date: Tue, 5 Jul 2016 08:33:35 -0700 Message-ID: <577BD34F.7000804@roeck-us.net> References: <1467724943-13416-1-git-send-email-s.christ@phytec.de> <1467724943-13416-2-git-send-email-s.christ@phytec.de> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from bh-25.webhostbox.net ([208.91.199.152]:35147 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751544AbcGEPdn (ORCPT ); Tue, 5 Jul 2016 11:33:43 -0400 In-Reply-To: <1467724943-13416-2-git-send-email-s.christ@phytec.de> Sender: linux-i2c-owner@vger.kernel.org List-Id: linux-i2c@vger.kernel.org To: Stefan Christ , linux-watchdog@vger.kernel.org, linux-i2c@vger.kernel.org On 07/05/2016 06:22 AM, Stefan Christ wrote: > Triggering the watchdog faster than T_WDMIN=256ms leads to resets of the > da9063 chip. The datasheet says that the watchdog must only be triggered > in the timeframe T_WDMIN to T_WDMAX. The T_WDMAX 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. > There isn't ? What is the problem with min_hw_heartbeat_ms which was introduced exactly for that purpose ? Thanks, Guenter