Re: [PATCH 0/4] Add support for off-channel powersave state in mac80211

[Seth Forshee <seth.forshee@canonical.com>]

On Wed, Feb 06, 2013 at 10:32:02PM +0100, Johannes Berg wrote:
> On Wed, 2013-02-06 at 15:01 -0600, Seth Forshee wrote:
> > Hi Johannes,
> > 
> > As promised, here are the patches which add the off-channel powesave
> > state. At a high level, the changes are:
> > 
> >  * Expand the PS configuration flag to be 2 bits and add helper
> >    functions for reading and setting the modes
> >  * Change the terminology around PS states, i.e. disabled -> awake and
> >    enabled -> doze
> >  * Add the off-channel PS state and put it to use
> >  * Minor driver updates based on these changes
> >  * Update brcmsmac to utilize the off-channel PS state

Hmm, I guess I should have mentioned that these patches were written on
top of the version 2 patches I sent for adding the off-channel queue
stop reason, etc. I'll need to resend them before they're likely to
apply cleanly anywhere.

> That's a lot of driver changes ... :)

A large number of those changes were made by sed ;-)

> I've been trying to disentangle the mess a bit. It looks like I was
> completely wrong about wl1251, it has HW scan so we don't care about its
> weird PS behaviour (1).
> 
> That leaves us with a few different drivers:
>  * iwlegacy -- has PS support but not NULLFUNC_STACK, so generates a
>    wakeup to the AP when we want to go scan ...
>  * drivers like iwlwifi/wl12xx have HW scan and don't set NULLFUNC_STACK
>  * drivers like ath5k/9k/... have all SW but set NULLFUNC_STACK
>  * drivers that just don't have powersave

I tried to ensure that the patches would result in equivalent behavior
for all drivers except brcmsmac (which will behave better). But I
obviously wan't able to test every driver to verify this.

I suspect b43 should also be updated similarly to brcmsmac. The only
hardware I have that uses b43 is a macbook whose wireless functions too
poorly to be a good test case.

Seth