From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jon Hunter <jonathanh-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
Subject: Re: [PATCH v2 1/2] i2c: tegra: Better handle case where CPU0 is busy
 for a long time
Date: Tue, 21 Apr 2020 20:42:40 +0100
Message-ID: <6f07e5c8-7916-7ea2-2fe7-d05f8f011471@nvidia.com>
References: <20200324191217.1829-1-digetx@gmail.com>
 <20200324191217.1829-2-digetx@gmail.com>
 <1e259e22-c300-663a-e537-18d854e0f478@nvidia.com>
 <f59ba318-8e99-c486-fa4d-1ee28a7b203d@gmail.com>
 <b01cec76-bb39-9fb5-8f6e-4023c075e6b3@gmail.com>
 <8cd085e1-f9fd-6ec0-9f7a-d5463f176a63@nvidia.com>
 <db1132ce-53a8-371c-98e0-cb7cd91d5c7d@gmail.com>
 <fa344989-4cce-0d2c-dc93-4ca546823160@nvidia.com>
 <bba0a93a-8ec4-eda6-97f3-fb2ab0b9b503@gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: quoted-printable
Return-path: <linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
In-Reply-To: <bba0a93a-8ec4-eda6-97f3-fb2ab0b9b503-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Content-Language: en-US
Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
To: Dmitry Osipenko <digetx-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Thierry Reding <thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Laxman Dewangan <ldewangan-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>, Wolfram Sang <wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org>, Manikanta Maddireddy <mmaddireddy-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>, Vidya Sagar <vidyas-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
List-Id: linux-tegra@vger.kernel.org


On 21/04/2020 16:08, Dmitry Osipenko wrote:
> 21.04.2020 17:40, Jon Hunter =D0=BF=D0=B8=D1=88=D0=B5=D1=82:
>>
>> On 21/04/2020 14:25, Dmitry Osipenko wrote:
>>> 21.04.2020 12:49, Jon Hunter =D0=BF=D0=B8=D1=88=D0=B5=D1=82:
>>> ...
>>>> I can try the above, but I agree it would be best to avoid messing wit=
h
>>>> 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.
>=20
> Perhaps the RPM's -EACCES is returned from here:
>=20
> https://elixir.free-electrons.com/linux/v5.7-rc2/source/drivers/base/powe=
r/runtime.c#L723
>=20
> 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.
>=20
> 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.
>=20
> 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

--=20
nvpublic