Re: [PATCH v3 04/18] i2c: omap: wakeup the controller during suspend() callback

From: Andy Shevchenko <andy@kernel.org>
To: Thomas Richard <thomas.richard@bootlin.com>
Cc: "Linus Walleij" <linus.walleij@linaro.org>,
	"Bartosz Golaszewski" <brgl@bgdev.pl>,
	"Tony Lindgren" <tony@atomide.com>,
	"Haojian Zhuang" <haojian.zhuang@linaro.org>,
	"Vignesh R" <vigneshr@ti.com>,
	"Aaro Koskinen" <aaro.koskinen@iki.fi>,
	"Janusz Krzysztofik" <jmkrzyszt@gmail.com>,
	"Andi Shyti" <andi.shyti@kernel.org>,
	"Peter Rosin" <peda@axentia.se>, "Vinod Koul" <vkoul@kernel.org>,
	"Kishon Vijay Abraham I" <kishon@kernel.org>,
	"Philipp Zabel" <p.zabel@pengutronix.de>,
	"Lorenzo Pieralisi" <lpieralisi@kernel.org>,
	"Krzysztof Wilczyński" <kw@linux.com>,
	"Rob Herring" <robh@kernel.org>,
	"Bjorn Helgaas" <bhelgaas@google.com>,
	linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org,
	linux-i2c@vger.kernel.org, linux-phy@lists.infradead.org,
	linux-pci@vger.kernel.org, gregory.clement@bootlin.com,
	theo.lebrun@bootlin.com, thomas.petazzoni@bootlin.com,
	u-kumar1@ti.com
Subject: Re: [PATCH v3 04/18] i2c: omap: wakeup the controller during suspend() callback
Date: Thu, 15 Feb 2024 17:30:44 +0200	[thread overview]
Message-ID: <Zc4uJBUuBzpNgxDP@smile.fi.intel.com> (raw)
In-Reply-To: <20240102-j7200-pcie-s2r-v3-4-5c2e4a3fac1f@bootlin.com>

On Thu, Feb 15, 2024 at 04:17:49PM +0100, Thomas Richard wrote:
> A device may need the controller up during suspend_noirq() or
> resume_noirq().
> But if the controller is autosuspended, there is no way to wakeup it during
> suspend_noirq() or resume_noirq() because runtime pm is disabled at this
> time.
> 
> The suspend() callback wakes up the controller, so it is available until
> its suspend_noirq() callback (pm_runtime_force_suspend()).
> During the resume, it's restored by resume_noirq() callback
> (pm_runtime_force_resume()). Then resume() callback enables autosuspend.
> 
> So the controller is up during a little time slot in suspend and resume
> sequences even if it's not used.

...

> +	/*
> +	 * If the controller is autosuspended, there is no way to wakeup it once
> +	 * runtime pm is disabled (in suspend_late()).
> +	 * But a device may need the controller up during suspend_noirq() or
> +	 * resume_noirq().
> +	 * Wakeup the controller while runtime pm is enabled, so it is available until
> +	 * its suspend_noirq(), and from resume_noirq().
> +	 */

It's a bit random line lengths...
Can you repack this to be more condensed?

-- 
With Best Regards,
Andy Shevchenko

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