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Date:   Wed, 2 Oct 2019 17:34:10 +0200
From:   Alexandre Belloni <alexandre.belloni@bootlin.com>
To:     Dmitry Torokhov <dtor@google.com>
Cc:     Nick Crews <ncrews@chromium.org>,
        Alessandro Zummo <a.zummo@towertech.it>,
        linux-rtc@vger.kernel.org, lkml <linux-kernel@vger.kernel.org>,
        Pavel Machek <pavel@ucw.cz>, enric.balletbo@collabora.com,
        Benson Leung <bleung@chromium.org>, dlaurie@chromium.org,
        Daniel Kurtz <djkurtz@chromium.org>
Subject: Re: [PATCH v3] rtc: wilco-ec: Handle reading invalid times
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On 02/10/2019 08:20:34-0700, Dmitry Torokhov wrote:
> > I'm still not convinced it is useful to have an error in dmesg when the
> > time is invalid, as long as userspace knows it is invalid. What is the
> > course of action for the end user when that happens?
> 
> Report it, or, in our case, we will see it in the feedback logs.
> However I do agree that it is not the best option, even if we report
> error to userspace I am not sure if it will handle it properly. What
> userspace is supposed to do when presented with -EIO or similar?
> 

I would say probably retry a few times if it gets -EIO and simply abort
in case of -EINVAL. I'm not aware of any userspace tool behaving that
way though. They all simply abort.

-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com