From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [RFC PATCH] i2c: remove use of in_atomic()
Date: Mon, 1 Apr 2019 13:21:09 +0200
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To: Wolfram Sang <wsa@the-dreams.de>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>, linux-i2c@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Frederic Weisbecker <fweisbec@gmail.com>, Ingo Molnar <mingo@kernel.org>, Thomas Gleixner <tglx@linutronix.de>
List-Id: linux-i2c@vger.kernel.org

On Mon, Apr 01, 2019 at 01:13:24PM +0200, Wolfram Sang wrote:

> > Why must we allow i2c usage with IRQs disabled? Just say NO?
>=20
> I'd love to. But quoting my patch description:
>=20
> "This matches the use cases for atomic I2C transfers I have seen so far:
> very late communication (mostly to a PMIC) to powerdown or reboot the
> system."

Ah, sorry, I missed that.

> And yes, I would never recommend a HW design to use I2C for shutting
> down/rebooting. But such HW is out there.

Can we then make the whole thing conditional on:

  system_state > SYSTEM_RUNNING

Such that we're sure to never trigger this under any other conditions?