What is needed to inplement a AP support in a driver?

What is needed to inplement a AP support in a driver?

[Maxim Levitsky]

I recently found that now ath5k supports AP mode.
I also found that most of the work is now done in userspace.

Since many drivers including my IWL3945 support sending beacons for IBSS
(strictly speaking userspace can send them too, but this is  sub
optimal), what else driver must support for AP?

Sending to several stations ? (IBSS already has this), have several
virtual devices (this is optional feature), what else?

Why iwl3945 still doesn't support AP mode?

If I patch it to support it (just add ap to list of allowed modes) will
it work? (I soon anyway try out....)

Best regards,
	Maxim Levitsky

Re: What is needed to inplement a AP support in a driver?

[Kalle Valo]

Maxim Levitsky <maximlevitsky@gmail.com> writes:

> I recently found that now ath5k supports AP mode.
> I also found that most of the work is now done in userspace.
>
> Since many drivers including my IWL3945 support sending beacons for IBSS
> (strictly speaking userspace can send them too, but this is  sub
> optimal), what else driver must support for AP?
>
> Sending to several stations ? (IBSS already has this), have several
> virtual devices (this is optional feature), what else?

At least sending multicast/broadcast frames immediately after DTIM
beacons. This is needed for clients in power save mode.

> Why iwl3945 still doesn't support AP mode?

No idea. I recall Intel talking about having patches to support AP mode
for iwl3945, but quick googling didn't reveal anything. All I found was
this from Tomas:

"We've enabled only iwl4965, not so ever effort was done for iwl3945

[...]

In general there should not problem to extend AP mode also for 3945 on
PC platform"

http://osdir.com/ml/linux.drivers.ipw3945.devel/2007-11/msg00184.html

It would be really nice to get AP mode support for iwl3945.
Unfortunately I don't have any spare time to work on that, but if you
are planning to work on it I (and others) can give you email support via
this mailing list.

-- 
Kalle Valo

Re: What is needed to inplement a AP support in a driver?

[Johannes Berg]

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On Tue, 2009-04-07 at 03:06 +0300, Maxim Levitsky wrote:
> I recently found that now ath5k supports AP mode.
> I also found that most of the work is now done in userspace.
> 
> Since many drivers including my IWL3945 support sending beacons for IBSS
> (strictly speaking userspace can send them too, but this is  sub
> optimal), what else driver must support for AP?

http://wireless.kernel.org/en/developers/Documentation/mac80211/API

> If I patch it to support it (just add ap to list of allowed modes) will
> it work? (I soon anyway try out....)

no.

johannes

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Re: What is needed to inplement a AP support in a driver?

[Rami Rosen]

Hi,
> Why iwl3945 still doesn't support AP mode?
see also this patch, titled: "wlwifi: disable AP mode"

http://www.spinics.net/lists/linux-wireless/msg24688.html

Regards,
Rami Rosen





On Tue, Apr 7, 2009 at 3:06 AM, Maxim Levitsky <maximlevitsky@gmail.com=
> wrote:
> I recently found that now ath5k supports AP mode.
> I also found that most of the work is now done in userspace.
>
> Since many drivers including my IWL3945 support sending beacons for I=
BSS
> (strictly speaking userspace can send them too, but this is =A0sub
> optimal), what else driver must support for AP?
>
> Sending to several stations ? (IBSS already has this), have several
> virtual devices (this is optional feature), what else?
>
> Why iwl3945 still doesn't support AP mode?
>
> If I patch it to support it (just add ap to list of allowed modes) wi=
ll
> it work? (I soon anyway try out....)
>
> Best regards,
> =A0 =A0 =A0 =A0Maxim Levitsky
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-wirel=
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> the body of a message to majordomo@vger.kernel.org
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>
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Re: What is needed to inplement a AP support in a driver?

[Maxim Levitsky]

On Tue, 2009-04-07 at 12:25 +0300, Rami Rosen wrote:
> Hi,
> > Why iwl3945 still doesn't support AP mode?
> see also this patch, titled: "wlwifi: disable AP mode"
> 
> http://www.spinics.net/lists/linux-wireless/msg24688.html
> 
> Regards,
> Rami Rosen


Quoiting this patch:


> iwlwifi does not support AP mode in any way. For one, it doesn't even
> buffer multicast/broadcast frames properly. We didn't allow zd1211rw AP
> mode to be enabled without this, so iwlwifi shouldn't be allowed to
> advertise AP mode either.
This is interesting, this means it doesn't save frames when client is in power save mode?
IBSS doesn't have this?



> 
> 
> 
> It also doesn't work at all, it doesn't even answer to probe requests,
> I'm guessing the packet injection code was disabled again.
Packet injection (even fragmentation) works fine here.
Also, now hostapd responds to probes isn't it?
(I was said that now hostapd sends/recieves all managment frames)


> 
> 
> [  471.524478] iwlagn: ERROR: APs don't scan
> 
> this is a long-standing bug, of course APs scan to know their
> surroundings, not sure why this is there, it's also very pointless since
> I can remove it by enabling software scan...
Here, software scan fixes it, besides many device don't have hardware scan
> 
> 
> 
> [  487.507346] iwlagn: Microcode SW error detected.  Restarting 0x2000000.
This probably was fixed now, there were many reports about microcode errors.
> 


I just feel, that AP mode can be done, and it isn't that hard to enable it.


Best regards,
	Maxim Levitsky

Re: What is needed to inplement a AP support in a driver?

[Maxim Levitsky]

On Tue, 2009-04-07 at 16:11 +0300, Maxim Levitsky wrote:
> On Tue, 2009-04-07 at 12:25 +0300, Rami Rosen wrote:
> > Hi,
> > > Why iwl3945 still doesn't support AP mode?
> > see also this patch, titled: "wlwifi: disable AP mode"
> > 
> > http://www.spinics.net/lists/linux-wireless/msg24688.html
> > 
> > Regards,
> > Rami Rosen
> 
> 
> Quoiting this patch:
> 
> 
> > iwlwifi does not support AP mode in any way. For one, it doesn't even
> > buffer multicast/broadcast frames properly. We didn't allow zd1211rw AP
> > mode to be enabled without this, so iwlwifi shouldn't be allowed to
> > advertise AP mode either.
> This is interesting, this means it doesn't save frames when client is in power save mode?
> IBSS doesn't have this?
> 
> 
> 
> > 
> > 
> > 
> > It also doesn't work at all, it doesn't even answer to probe requests,
> > I'm guessing the packet injection code was disabled again.
> Packet injection (even fragmentation) works fine here.
> Also, now hostapd responds to probes isn't it?
> (I was said that now hostapd sends/recieves all managment frames)
> 
> 
> > 
> > 
> > [  471.524478] iwlagn: ERROR: APs don't scan
> > 
> > this is a long-standing bug, of course APs scan to know their
> > surroundings, not sure why this is there, it's also very pointless since
> > I can remove it by enabling software scan...
> Here, software scan fixes it, besides many device don't have hardware scan
> > 
> > 
> > 
> > [  487.507346] iwlagn: Microcode SW error detected.  Restarting 0x2000000.
> This probably was fixed now, there were many reports about microcode errors.
> > 
> 
> 
> I just feel, that AP mode can be done, and it isn't that hard to enable it.
> 

I am thinking, currently iwl3945 is ported to iwlagn.
When porting is it could fix AP problems in it too?


Best regards
	Maxim Levitsky