machdep.kbdreset enables a shutdown by Ctrl-Alt-Del on amd64 and

i386.  Stop abusing it on other archs for controling a shutdown by
pressing the soft power button:

* Add a MI sysctl hw.allowpowerdown; if set to 1 (the default) it
  allows a power button shutdown.
* Make acpi(4)/acpibtn(4) honor hw.allowpowerdown.
* Switch the various power button intercepts on landisk, sgi, sparc64
  and zaurus over to hw.allowpowerdown.
* Garbage collect the machdep.kbdreset sysctl on all archs other than
  amd64 and i386.

ok miod@

1 files changed, 6 insertions, 3 deletions

diff --git a/share/man/man4/acpibtn.4 b/share/man/man4/acpibtn.4
index 5a21f928dcf..a93e437813e 100644
--- a/share/man/man4/acpibtn.4
+++ b/share/man/man4/acpibtn.4
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: acpibtn.4,v 1.3 2007/05/31 19:19:48 jmc Exp $
+.\"	$OpenBSD: acpibtn.4,v 1.4 2011/06/24 19:47:48 naddy Exp $
 .\"
 .\" Copyright (c) 2006 Michael Knudsen <mk@openbsd.org>
 .\"
@@ -14,7 +14,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: May 31 2007 $
+.Dd $Mdocdate: June 24 2011 $
 .Dt ACPIBTN 4
 .Os
 .Sh NAME
@@ -29,7 +29,10 @@ driver is used to handle the event triggered when the user presses an ACPI
 button.
 Currently, the only event handled is the press of a power button which
 causes the system to perform a regular system shutdown and power off the
-machine.
+machine if the
+.Va hw.allowpowerdown
+.Xr sysctl 8
+is set to 1.
 .Sh SEE ALSO
 .Xr acpi 4 ,
 .Xr intro 4