Date: Thu, 7 Feb 2013 14:10:44 -0600
From: Seth Forshee <seth.forshee@canonical.com>
To: Arend van Spriel <arend@broadcom.com>
Cc: Johannes Berg <johannes@sipsolutions.net>,
	linux-wireless@vger.kernel.org,
	"John W. Linville" <linville@tuxdriver.com>,
	brcm80211-dev-list@broadcom.com
Subject: Re: [PATCH 0/4] Add support for off-channel powersave state in
 mac80211
Message-ID: <20130207201044.GC4378@thinkpad-t410> (sfid-20130207_211059_344595_328B2B8B)
References: <1360184478-31481-1-git-send-email-seth.forshee@canonical.com>
 <1360186322.7910.76.camel@jlt4.sipsolutions.net>
 <20130207181543.GA4378@thinkpad-t410>
 <51140811.3000108@broadcom.com>
MIME-Version: 1.0
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In-Reply-To: <51140811.3000108@broadcom.com>
Sender: linux-wireless-owner@vger.kernel.org

On Thu, Feb 07, 2013 at 09:01:21PM +0100, Arend van Spriel wrote:
> On 02/07/2013 07:15 PM, Seth Forshee wrote:
> > 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.
> 
> If I recall correctly b43 has a Kconfig option to allow it to support
> the same devices brcmsmac supports.

You're right; I forgot about that. It looks like that will make it at
least claim to support my BCM43224. I'll have to give that a try.

Thanks for the suggestion.

Seth