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Date: Fri, 22 Sep 2023 13:46:56 +0200
From: Marek =?UTF-8?B?QmVow7pu?= <kabel@kernel.org>
To: Guenter Roeck <linux@roeck-us.net>
List-Id: <soc.lore.kernel.org>
Cc: Gregory CLEMENT <gregory.clement@bootlin.com>, Arnd Bergmann
 <arnd@arndb.de>, soc@kernel.org, arm@kernel.org, Wim Van Sebroeck
 <wim@linux-watchdog.org>, linux-watchdog@vger.kernel.org
Subject: Re: [PATCH v2 5/7] platform: cznic: turris-omnia-mcu: Add support
 for MCU watchdog
Message-ID: <20230922134656.23171869@dellmb>
In-Reply-To: <5940424f-ebaf-a73b-4157-fc3fb7fa7d3c@roeck-us.net>
References: <20230919103815.16818-1-kabel@kernel.org>
	<20230919103815.16818-6-kabel@kernel.org>
	<5940424f-ebaf-a73b-4157-fc3fb7fa7d3c@roeck-us.net>
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> > +static int omnia_wdt_start(struct watchdog_device *wdt)
> > +{
> > +	struct omnia_mcu *mcu = watchdog_get_drvdata(wdt);
> > +
> > +	/*
> > +	 * The MCU also implements LED controller, and the LED driver may in
> > +	 * some cases require more I2C bandwidth. In order to prevent stealing
> > +	 * that bandwidth from the LED driver, configure minimum time between
> > +	 * pings to 10% of the configured timeout (for 120 second timeout we
> > +	 * will be pinging at most every 12 seconds).
> > +	 */
> > +	mcu->wdt.min_hw_heartbeat_ms = 100 * mcu->wdt.timeout;  
> 
> This is not what min_hw_heartbeat_ms is supposed to be used for, and it is
> an abuse of the API which is not guaranteed to work. The value is exopected
> to be set at registration time, and it is not supposed to change dynamically.
> It is also competely unnecessary since no sane watchdog daemon will ping
> at such a high rate. Please drop.

Hello Guenter, thanks for the review.

Sorry about this, I thought this was correct cause rti_wdt driver and
feared that watchdog daemons would actually ping at such rate.

I will drop it in the next version of the series.

Marek