[parisc-linux] Power LED

Helge Deller helge.deller@sap.com
Mon, 18 Feb 2002 10:21:17 +0100

On Monday 18 February 2002 08:37, Hinrich Aue wrote:
> When I push the power-button on my 715/80, it prints a
> message on the screen, that a shuwdown is requested,
> and then shuts down immediatly. On the next start up a
> fsck is required.
> It seems to be software controlled, or it would not
> print that message(I think).
> Maybe a shutdown signal is emmited from the kernel at
> one point, but the runlevel isn't changed before.
> So it should be possible to isolate that signal and
> use it seperately in the atx style.
> (I'm not a kernel hacker, but maybe this is a starting
> point?)
> Just speculating.

715/64, 715/80 and 715/100 belong to the so-called
715/new machines and all of those support the soft-power
switch, else you wouldn't have received the 
"Shutdown requested..." message. 
In your case I assume, that your filesystems wasn't clean
before you did shutdown your system....

BTW, the shutdown is initiated by the kernel by sending
a SIGINT to the PID (cad_pid) of the init process. This
is done in the file power.c:
After receiving this signal the init process switches the runlevel,
shuts down your system cleanly and runs /sbin/poweroff
or /sbin/halt. This is already the case and is also done
that way for ATX systems.

Helge Deller
SAP AG - LinuxLab and Unix Platforms
email: helge.deller@sap.com