Re: rt2x00 mesh support

[Ivo van Doorn <ivdoorn@gmail.com>]

On Wednesday 18 March 2009, Johannes Berg wrote:
> On Wed, 2009-03-18 at 13:48 +0100, Ivo van Doorn wrote:
> 
> > Excellent thanks. :)
> > 
> > Johannes, my previous assumption is apparently correct,
> > The following is happening:
> > 
> > ieee80211_open()
> > 	-> ops->add_interface()
> > 	-> ieee80211_start_mesh()
> > 		->  ieee80211_if_config()
> > 			-> ops->config_interface()
> > 	-> ieee80211_hw_config()
> > 		-> ops->config()
> > 
> > Because config_interface() is called before config() the radio
> > is not enabled at the moment config_interface() is called and
> > the call to config() will effectively disable beaconing.
> 
> Ah. I thought you were saying ->start() came after ->config_interface(),

Yeah that was my first guess :)

> ->config() coming after it makes no sense either but we haven't even
> tried to avoid that so far... In fact, it is perfectly legal for
> ->config() to be called after ->config_interface() when, for example,
> you change the channel. Not that I disagree -- we should be setting the
> beacon interval before enabling beaconing...

True, the problem however is that when enabling the radio it is possible/likely
that a lot of settings will be lost. For rt2x00 we must reset almost all registers
to make sure everything is set correctly again.

> What exactly is the problem here? The fact that we don't enable the
> radio until after having configured beaconing? I'm not sure how to solve
> this, to be honest.

Neither do I, perhaps we should make sure that a call to config() when
the enabled_radio field has changed should trigger additional reconfigurations
as well. But I don't really like such a solution.. :(

Perhaps should check if a beacon was provided while the radio was off,
and either request a new beacon or upload the previously provided beacon when
the radio is being enabled.

Ivo