svn commit: r193159 - head/sys/powerpc/powermac

[Nathan Whitehorn]

John Baldwin wrote:
> On Sunday 31 May 2009 6:02:20 am Nathan Whitehorn wrote:
>   
>> Author: nwhitehorn
>> Date: Sun May 31 10:02:20 2009
>> New Revision: 193159
>> URL: http://svn.freebsd.org/changeset/base/193159
>>
>> Log:
>>   Provide an analogous sysctl to hw.acpi.acline (dev.pmu.0.acline) to
>>   determine whether the computer is plugged in to mains power.
>>     
>
> I wonder if it would be a good idea to introduce a 
> platform-independent 'acline' sysctl?  Something like 'hw.acline'?  For now 
> we could simply have these devices create it.  We could do something fancier 
> where AC adapter drivers register with a centralized thingie at some point 
> and it exports a global setting that is true so long as at least one adapter 
> is online.  I'm not sure that level of complexity is warranted until we have 
> platforms with multiple AC lines exposed to the OS though.
>   
That would be nice, and easy to implement, though the existing one 
should be kept for a while for compatibility. In the longer term, pmu(4) 
also provides an ACPI-alike interface to battery status under dev.pmu.*, 
which it would likewise be good to report in a platform-independent way.
-Nathan