Re: [PATCH v2 1/2] i2c: tegra: Better handle case where CPU0 is busy for a long time

From: Jon Hunter
Date: Tue Apr 21 2020 - 15:42:47 EST



On 21/04/2020 16:08, Dmitry Osipenko wrote:
> 21.04.2020 17:40, Jon Hunter ÐÐÑÐÑ:
>>
>> On 21/04/2020 14:25, Dmitry Osipenko wrote:
>>> 21.04.2020 12:49, Jon Hunter ÐÐÑÐÑ:
>>> ...
>>>> I can try the above, but I agree it would be best to avoid messing with
>>>> the suspend levels if possible.
>>>
>>> Will be awesome if you could try it and report back the result.
>>>
>>
>> I gave it a try but suspend still fails.
>
> Perhaps the RPM's -EACCES is returned from here:
>
> https://elixir.free-electrons.com/linux/v5.7-rc2/source/drivers/base/power/runtime.c#L723
>
> Which suggests that I2C is accessed after being suspended. I guess the
> PCIe driver suspends after the I2C and somehow my change affected the
> suspension order, although not sure how.
>
> Jon, could you please try to enable PM logging and post the log? Please
> also post log of the working kernel version, so that we could compare
> the PM sequence.
>
> Something like this should enable the logging: "echo 1 >
> /sys/power/pm_trace" + there is RPM tracing.

Unfortunately, after enabling that I don't any output and so no help there.

Jon

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