Re: [PATCH v3 05/22] i2c: tegra: Use reset_control_reset()

From: Dmitry Osipenko
Date: Thu Sep 03 2020 - 11:10:19 EST


03.09.2020 14:11, Andy Shevchenko пишет:
> On Thu, Sep 3, 2020 at 3:53 AM Dmitry Osipenko <digetx@xxxxxxxxx> wrote:
>>
>> Use a single reset_control_reset() instead of assert/deasset couple in
>> order to make code cleaner a tad.
>
>> Note that the reset_control_reset()
>> uses 1 microsecond delay instead of 2 that was used previously, but this
>> shouldn't matter.
>
> What datasheet says about this delay?

The public datasheet doesn't say anything specific about the I2C
controller reset time. IIUC, controller logic runs at 200/400 MHz, so
1us should be enough for the reset.

I'm sure that somebody from NVIDIA should know the exact answer and will
correct me if I'm wrong. I CC'd Peter De Schrijver who is a maintainer
of the Tegra's clock-and-reset driver.