On Fri, Dec 4, 2009 at 4:12 AM, Kalle Valo <kalle.valo@xxxxxx> wrote: > Jason Young <a.young.jason@xxxxxxxxx> writes: > >> Hi, > > Hello, > >>>> here is my proposal how to add U-APSD client support to mac80211. I also >>>> included example driver implementation for wl1251. >>>> >>>> Please comment. Also I would like to get comments how U-APSD needs to be >>>> implemented in different hardware. >> >> WMM Admission Control allows queues to be configured as trigger-only >> and deliver-only via mgmt action frames. If this feature is ever >> added to mac80211 we may need to make trigger-enabled and >> deliver-enabled per queue configuration explicit rather than a >> single boolean value per access category. Being as there is no way >> to configure an access category trigger-only or deliver-only outside >> of admission control, we don't need to worry about this problem >> right now. > > I decided to drop Admission Control for now because I didn't see any > real use case for it. And if we would like to utilise it properly, we > would need to have properly supported user space interface. I think we > are not ready for that quite yet. > There are real use cases for WMMAC, particularly in enterprise environments but I don't want to get into that discussion just yet, first things first :) I just wanted it to be noted somewhere in the discussion of this proposal that U-APSD can, in theory at least, be configured as trigger or delivery only. Some hardware may be implemented to allow trigger/delivery only configuration. In such cases, the driver will need to update both the trigger and delivery state based on the uapsd boolean parameter. >> We will want runtime time configuration of u-apsd because its is >> necessary for station's 'WMM Power Save' certification. Recompiling >> mac80211 for the various uapsd configurations is a bit heavy-handed. >> I'd like to see debugfs support added back back for now its >> primarily a testing issue anyway. > > Thanks, I wasn't aware of this. Yes, adding the debugfs interface back > makes sense now. But can you describe a bit more how you would like to > use the debugfs interface? I would like to understand about your needs > a bit more. > > I also need to find the certification test plan and read it myself. Section 2.8.1 of the "WMM Power Save Test Plan Version 1.5" describes the basic station requirements. Section 5 describes the station specific tests. I would like to be able to set the uapsd configuration of each AC independently, as well as the Max SP length. Basically, the bits that get used in the qosinfo field during association. Because this should just be used for testing or until we add a real userspace API, I'm fine with requiring the user to manually reconnect to have new U-APSD configuration adopted. >>>> - add max SP length defines to ieee80211.h >> >> The bit values for IEEE80211_WMM_IE_STA_SP_XXX are not correct. The >> Max SP Length subfield settings table in 7.3.1.17 has the least >> significant bit listed first. > > Oh, I missed that entirely. And I was even thinking why the order > looked so weird (0, 2, 1, 3), I should have checked that. Thank you > for noticing this. > >>>> v2: >>>> - remove cfg80211 changes >>>> - rename IEEE80211_QOS_IE to IEEE80211_WMM_IE_STA in ieee80211.h >> >> I would rename IEEE80211_WMM_IE_STA_XXX defines to something like >> IEEE80211_STA_QOSINFO_XXX to make it clear that bit values are used in the >> context of the qosinfo field octet. > > Good point. Is IEEE80211_WMM_IE_STA_QOSINFO_AC_VO clear enough? At > least it's long enough :) Hah, ya. > Thank you for the comments, I appreciate them. > > -- > Kalle Valo > Jason Young DSP Group -- 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
