On Thu, Jan 31, 2013 at 06:50:34PM +0100, Johannes Berg wrote: > On Thu, 2013-01-31 at 11:18 -0600, Seth Forshee wrote: > > > > > Actually one of the last bugs I fixed before sending these was a place > > > > where I had used disabled instead of !enabled, and the frames ended up > > > > with PM set when it shouldn't have been. > > > > > > > > I agree though that the distinction is confusing. Maybe some better > > > > state names are needed. Perhaps awake, offchannel, and doze? > > > > > > I think what you really want is to distinguish between "HW can go to > > > powersave" and "PM bit should be set"? That's pretty much what your > > > CONF_PS_ENABLED and CONF_PS_OFFCHANNEL means, respectively, but maybe > > > > Correct, with the understanding that "HW can go to powersave" also > > implies "PM bit should be set." > > > > Another approach would be to keep the CONF_PS flag the same and add a > > CONF_PM flag or similar. I didn't go with this approach because CONF_PS > > && !CONF_PM really doesn't make any sense, which really doesn't help > > with reducing confusion. The advantage is that it separates setting PM > > from PS for those driver that don't support PS but need to configure the > > hardware to set PM for off-channel. > > Good point, that'd work too. PS && !PM would never be used, I guess? > It'd also have the advantage of not having to touch all the drivers? > > It doesn't really matter all that much to me though, I just think what > you have right now is (too) confusing. Hi Johannes, I've been thinking about and playing around with these ideas. I've implemented the CONF_PM idea, and it does end up with fewer changes, but I just don't think separating powersave from setting PM makes much sense. In the end it just seems like a kludge to fix a problem with Broadcom chips, and if I want a kludge I can do it entirely within the driver. So what I'm planning to do know is implement the awake/doze/offchannel powersave modes like I had mentioned, but taking things a bit further. I'd change IEEE80211_HW_SUPPORTS_PS to SUPPORTS_PS_DOZE, indicating support for a low-power powersave state rather than support for powersave in general. All hardware will be reconfigured for awake<->offchannel transitions (though most drivers can simply ignore these transitions), but hardware will only be put in the doze state if it indicates PS_DOZE support. This will make it compulsory for all drivers to indicate whether or not they require IEEE802111_HW_PS_NULLFUNC_STACK. I'll simply set this flag for any drivers not currently supporting powersave. In practice the changes shouldn't end up much different than what I have in these patches, but I think it's conceptually cleaner (and less confusing!). Does this sound reasonable to you? Thanks, Seth -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
