rfc: wake on lan patches for review

[Stefan Sperling]

Hello Hackers,

I have written a patch for the if_sis driver that enables
wake on lan on the NatSemi DP8381[56] network chip.
This did not work before because the driver needs to explicitely
configure the card to enter wake on lan mode on system shutdown.

I also added ioctls to make wake events configurable from userspace,
and added an according 'wakeon <events>' command to ifconfig.
The ioctls should be general enough to be used with other chips that
require a similar configuration procedure for wake on lan.

Before making efforts to get this committed I'd appreciate any comments
and suggestions you may have. I'd especially appreciate people trying
this at home if they have access to a network card with above mentioned
chip.

If you have a different card with wake on lan support that did not
yet work as expected (i.e. your box does not wake up after shutting it
down from FreeBSD), and have a datasheet available you might want to
have a look at my code as an example on how to add wake on lan support
to your card's driver. In my case, there wasn't much more to it than
writing a couple of registers during the driver's shutdown procedure
and implementing the new ioctls.

You can find the patch at http://stsp.in-berlin.de/wol/

The patch applies cleanly to -current as of July 17th,
and will probably apply to RELENG_6 just as well.

regards,
-- 
stefan
http://stsp.in-berlin.de                                 PGP Key: 0xF59D25F0