2008-04-15 04:24:47

by cao jing

[permalink] [raw]
Subject: AR5K_INT_SWBA can't generate interruption for sending beacons

Hi,

I'm working on mac80211 and ath5k. I found that the AR5K_INT_SWBA
interruption can't be generated. So I can't send beacons by this
interruption. Anyone knows what's going on with it?

Thank you very much!

Jing


2008-04-15 08:54:21

by Holger Schurig

[permalink] [raw]
Subject: Re: AR5K_INT_SWBA can't generate interruption for sending beacons

Oh, I was speaking complete nonsense. I confused ath5k with
ath6k.


2008-04-15 08:39:52

by Holger Schurig

[permalink] [raw]
Subject: Re: AR5K_INT_SWBA can't generate interruption for sending beacons

> Hi,
>
> I'm working on mac80211 and ath5k. I found that the
> AR5K_INT_SWBA interruption can't be generated. So I can't send
> beacons by this interruption. Anyone knows what's going on
> with it?
>
> Thank you very much!

ath5k didn't make it yet to wireless-testing. That is the git
tree for all wireless stuff that finally will make it into
mainline Linux. See http://linuxwireless.org for more detail.

I know that some people from the the OpenMoko work with ATH5K,
but so far none of the people that work with ATH5K bothered to
submit the driver have submitted the driver or asked for
review/inclusion. Therefore I fear that the work development
force isn't united, but scattered here ...


Also, because ath5k didn't make it into wireless-testing yet, you
might not find people that know the device well enought here.

2008-04-16 08:43:14

by Bruno Randolf

[permalink] [raw]
Subject: Re: AR5K_INT_SWBA can't generate interruption for sending beacons

On Wednesday 16 April 2008 08:01:09 Jouni Malinen wrote:
> On Tue, Apr 15, 2008 at 10:59:05AM +0200, bruno randolf wrote:
> > the current code in wireless-testing uses SWBA not to send beacons but to
> > keep track of the next beacon time NBTT. this is necessary to work around
> > certain hardware limitations. once configured, the beacons are sent
> > automatically by the hardware at the right time. of course it would be
> > possible to change the code to generate a new beacon at every SWBA but as
> > long as the beacon contents don't change very often i don't see the point
> > of doing so.
>
> In AP mode, beacon payload changes for _every beacon_ unless you use
> DTIM Period of 1. In order to make power saving work correctly, the
> drivers need to update the beacon data for every beacon.

thats's true - i was thinking of IBSS mode first of all since AP mode is not
supported yet by ath5k. actually also in IBSS mode the beacon contents would
have to change for power saving, this is also not implemented yet.

bruno

2008-04-16 06:02:55

by Jouni Malinen

[permalink] [raw]
Subject: Re: AR5K_INT_SWBA can't generate interruption for sending beacons

On Tue, Apr 15, 2008 at 10:59:05AM +0200, bruno randolf wrote:
> the current code in wireless-testing uses SWBA not to send beacons but to keep
> track of the next beacon time NBTT. this is necessary to work around certain
> hardware limitations. once configured, the beacons are sent automatically by
> the hardware at the right time. of course it would be possible to change the
> code to generate a new beacon at every SWBA but as long as the beacon
> contents don't change very often i don't see the point of doing so.

In AP mode, beacon payload changes for _every beacon_ unless you use
DTIM Period of 1. In order to make power saving work correctly, the
drivers need to update the beacon data for every beacon.

--
Jouni Malinen PGP id EFC895FA

2008-04-15 09:20:44

by Bruno Randolf

[permalink] [raw]
Subject: Re: AR5K_INT_SWBA can't generate interruption for sending beacons

On Tuesday 15 April 2008 10:36:55 Holger Schurig wrote:
> > I'm working on mac80211 and ath5k. I found that the
> > AR5K_INT_SWBA interruption can't be generated. So I can't send
> > beacons by this interruption. Anyone knows what's going on
> > with it?

the current code in wireless-testing uses SWBA not to send beacons but to keep
track of the next beacon time NBTT. this is necessary to work around certain
hardware limitations. once configured, the beacons are sent automatically by
the hardware at the right time. of course it would be possible to change the
code to generate a new beacon at every SWBA but as long as the beacon
contents don't change very often i don't see the point of doing so.

> ath5k didn't make it yet to wireless-testing. That is the git
> tree for all wireless stuff that finally will make it into
> mainline Linux. See http://linuxwireless.org for more detail.

i don't know how you come to that conclusion - ath5k *is* in wireless-testing
and there are a few people working on it.

bruno