From: Alexandre Belloni <alexandre.belloni@free-electrons.com>
To: Tim Harvey <tharvey@gateworks.com>
Cc: Sebastian Reichel <sre@kernel.org>,
linux-pm@vger.kernel.org, rtc-linux@googlegroups.com
Subject: Re: [rtc-linux] Re: where in sysfs should I put the ability to power down a board for a specific time?
Date: Tue, 27 Oct 2015 16:29:58 +0100 [thread overview]
Message-ID: <20151027152958.GE22331@piout.net> (raw)
In-Reply-To: <CAJ+vNU1vH2kr5snXiO2dCLcw=DViNLBtwxqsiAM4-xpMhu9w0w@mail.gmail.com>
Hi,
On 27/10/2015 at 07:55:28 -0700, Tim Harvey wrote :
> The power-off process is a discrete step from setting the wakeup time.
> By 'poweroff controller' I'm assuming you mean implement a
> pm_power_off hook which makes sense.
>
> While I'm at it it seems like implementing arm_pm_restart makes a lot
> of sense as well as the device can toggle board power which should be
> preferred over a chip-level reset.
>
Sure, then you can probably make an MFD which is the proper way of
register one device in multiple susbsytems. I just happened to give a
talk on that topic:
http://free-electrons.com/pub/conferences/2015/elce/belloni-mfd-regmap-syscon/belloni-mfd-regmap-syscon.pdf
> I was looking for a standard userspace sysfs API in (ie
> /sys/class/power?) that will call kernel_restart or kernel_power_off
> but the only thing I've found is either the reboot syscall or sysrq (o
> or b). Have I missed something or are these the expected userspace
> API's for power-off/reset?
Yeah, I'm guessing this is the correct API, people usually use
halt/poweroff/shutdown/reboot which should all end up calling the reboot
system call.
--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
prev parent reply other threads:[~2015-10-27 15:30 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-10-20 15:12 where in sysfs should I put the ability to power down a board for a specific time? Tim Harvey
2015-10-20 21:21 ` Sebastian Reichel
2015-10-24 2:12 ` [rtc-linux] " Alexandre Belloni
2015-10-27 14:55 ` Tim Harvey
2015-10-27 15:29 ` Alexandre Belloni [this message]
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