linux-kernel - Re: [PATCH 0/3] Ensure Low period of SCL is correct

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Message-ID: <7hee2lu82n.fsf@baylibre.com>
Date:   Mon, 28 Mar 2022 13:37:52 -0700
From:   Kevin Hilman <khilman@...libre.com>
To:     Lucas Tanure <tanure@...ux.com>,
        Neil Armstrong <narmstrong@...libre.com>,
        Jerome Brunet <jbrunet@...libre.com>,
        Martin Blumenstingl <martin.blumenstingl@...glemail.com>
Cc:     linux-i2c@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-amlogic@...ts.infradead.org, linux-kernel@...r.kernel.org,
        Lucas Tanure <tanure@...ux.com>
Subject: Re: [PATCH 0/3] Ensure Low period of SCL is correct

Hi Lucas,

Lucas Tanure <tanure@...ux.com> writes:

> The default duty cycle of 33% is less than the required
> by the I2C specs for the LOW period of the SCL clock.
>
> So, for 100Khz or less, use 50%H/50%L duty cycle, and
> for the clock above 100Khz, use 40%H/60%L duty cycle.
> That ensures the low period of SCL is always more than
> the minimum required by the specs at any given frequency.

Thanks for the fixes!

This is going to affect all SoCs, so ould you please summarize how your
changes were tested, and on which SoCs & boards?

Thanks,

Kevin