Subject: Re: ath driver and wep
To: Greg Troxel <gdt@ir.bbn.com>
From: Sam Leffler <sam@errno.com>
List: current-users
Date: 10/02/2005 11:22:52
Greg Troxel wrote:
> Sam Leffler <sam@errno.com> writes:
> 
> 
>>Greg Troxel wrote:
>>
>>None my laptops resume properly on freebsd (undoubtedly operator error).
> 
> 
> I think you mean they don't resume at all, so you therefore don't know
> if ath resume works.

I can resume but there are some issues that keep the system from being 
usable.  Hence I've never put effort into checking issues like this.

I've never had any complaints from anyone (freebsd, linux, or otherwise) 
about suspend/resume but we know this means little.  I'm checking what 
happens when the chip is put in full sleep but like I said before if 
cardbus sockets are powered off then something must be done over and 
above what currently is being done.

> 
> 
>>> It seems reasonable to allow drivers to power off cards that are
>>> not UP.  I wonder if it makes sense to have a call in net80211
>>> that a driver can invoke to say "push hardware settings to me
>>> again" that invokes the wep key write methods and perhaps other
>>> things.  This may be the only case, but it felt like a bit of an
>>> abstraction violation to be iterating over the key array.
>>
>>It's likely something must be done specially for resume because
>>there are more than wep keys to restore (e.g. the unicast key(s) for
>>wpa/802.1x).  To be honest sta mode operation has been lower
>>priority than ap mode; e.g. I still haven't finished power save
>>support.
> 
> 
> I think what you are saying is that resume is harder than powering up
> only for UP, since at resume time we might have per-peer state to push
> into the key cache.  When bringing an interface UP, there shouldn't be
> any such state since and up->down transition presumably clears the
> node table.

All ath key caches have more entries than the 4 used for the global (aka 
wep) key table.  It's rare that only the first 4 entries are used; even 
in sta mode you use other entries.  This means that if you want to 
handle the most general case you must be prepared to restore all the 
data which may require mucking with the net80211 data structures (or get 
help from the net80211 layer to minimize layer violations).

> 
> I don't see how AP mode avoids the losing wep keys when powered down
> issue.

ap's don't get suspended.

> 
> I'm using ibss mode, for what that's worth.
> 

	Sam