Re: [PATCH 1/2] PM: fast power off - core

[akuster <akuster@mvista.com>]

Pavel Machek wrote:
> Hi!
> 
>> Fastpoweroff  allows a user to power down the system without using rc kill
>> scripts. This is used in the advent of a battery operated device about to lose
>> power.  The user interface is vis sysfs /sys/power/fastpoweroff. A simple cat of
>> the fastpoweroff will list any registered profiles.  To invoke
>> the profile sequence, echo {profile name} > /sys/power/fastpoweroff.
> 
> No, we do not want "poweroff profiles" in kernel. Sorry.
No need to be.

> 
> rc kill scripts should be fast enough, if not, fix them. If it is
> impossible (time is spent in kernel waiting for network card to shut
> off), fix that.
> 
> What you want is pretty much "echo b > ..../sysrq; halt --now".

The one draw back is that Magic sysrq needs to be enabled and it might 
not be desired in a deployed system.  "echo u " is more of what I was 
looking for.

Thanks for you time.

Armin