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

["Arend van Spriel" <arend@broadcom.com>]

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.

Gr. AvS