linux-kernel - RE: [PATCH] spi/atmel: add support for runtime PM

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 20 Oct 2014 02:05:42 +0000
From:	"Yang, Wenyou" <Wenyou.Yang@...el.com>
To:	Kevin Hilman <khilman@...nel.org>, Mark Brown <broonie@...nel.org>
CC:	"linux-spi@...r.kernel.org" <linux-spi@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"Ferre, Nicolas" <Nicolas.FERRE@...el.com>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>
Subject: RE: [PATCH] spi/atmel: add support for runtime PM



> -----Original Message-----
> From: Kevin Hilman [mailto:khilman@...nel.org]
> Sent: Friday, October 17, 2014 10:22 PM
> To: Mark Brown
> Cc: Yang, Wenyou; linux-spi@...r.kernel.org; linux-kernel@...r.kernel.org; Ferre,
> Nicolas; linux-arm-kernel@...ts.infradead.org
> Subject: Re: [PATCH] spi/atmel: add support for runtime PM
> 
> Mark Brown <broonie@...nel.org> writes:
> 
> > On Fri, Oct 17, 2014 at 06:02:35AM -0700, Kevin Hilman wrote:
> >> Wenyou Yang <wenyou.yang@...el.com> writes:
> >
> >> > +	if (!pm_runtime_suspended(dev)) {
> >> > +		clk_disable_unprepare(as->clk);
> >> > +		pinctrl_pm_select_sleep_state(dev);
> >> > +	}
> >
> >> a.k.a. pm_runtime_put_sync() since the ->runtime_suspend() callback
> >> does the same thing.
> >
> > Will that do the right thing when runtime PM is disabled in Kconfig?
> 
> Good point.
> 
> Then the way to make this cleaner, and obvious on inspection that system
> suspend/resume are doing the same thing as runtime suspend/resume is to have -
> >suspend call the runtime_suspend function.
> 
> The runtime suspend/resume functions then should be wrapped in CONFIG_PM
> instead of CONFIG_PM_RUNTIME.
But if the runtime PM is disabled,  __pm_runtime_idle() return -ENOSYS, which invoked by pm_runtime_put_sync(), in spite of the runtime suspend/resume functions wrapper,

> 
> Kevin

Best Regards,
Wenyou Yang
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/