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From:   Baolin Wang <baolin.wang@linaro.org>
Date:   Wed, 8 Nov 2017 13:48:54 +0800
Message-ID: <CAMz4kuJNALMSmGV7tSiGZMj6S2=5LyfaqTpzowzM95gLKpHO1A@mail.gmail.com>
Subject: Re: [PATCH 2/2] rtc: sprd: Add Spreadtrum RTC driver
To:     Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc:     Baolin Wang <baolin.wang@spreadtrum.com>,
        Alessandro Zummo <a.zummo@towertech.it>,
        Rob Herring <robh+dt@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        devicetree@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
        linux-rtc@vger.kernel.org, Mark Brown <broonie@kernel.org>
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On 8 November 2017 at 13:35, Alexandre Belloni
<alexandre.belloni@free-electrons.com> wrote:
> On 08/11/2017 at 13:29:21 +0800, Baolin Wang wrote:
>> > Don't do that. This is a valuable information. If you know the time is
>> > invalid, return -EINVAL in read_time(). What your are doing here is
>> > confusing the system by making it believe your fake date is the correct
>> > time.
>>
>> Usually for mobile device, we should give one reasonable start time if
>> the RTC powered down. Anyway I can remove this feature now.
>> Very appreciated for your helpful comments.
>
> Then userspace will have -EINVAL when reading the RTC and will be able
> to set the RTC to whatever value it wants. Don't encode that policy in
> the kernel.

That's great. Thanks for explanation.

-- 
Baolin.wang
Best Regards

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