On Sat, Jul 12, 2008 at 3:57 PM, Bruno Randolf <br1@xxxxxxxxxxx> wrote: > On Thursday 10 July 2008 16:47:57 Tomas Winkler wrote: >> On Thu, Jul 10, 2008 at 4:52 PM, Johannes Berg >> >> <johannes@xxxxxxxxxxxxxxxx> wrote: >> > On Thu, 2008-07-10 at 15:25 +0300, Tomas Winkler wrote: >> >> > what about using the generic function to add the radiotap header from >> >> > mac80211? it should be flexible enough to handle all devices by now. >> >> >> >> Why not go ahead. >> > >> > I always thought you were adding 11n stuff, but if that's not the case >> > (and we may make mac80211 do that at some point) then that'd be a nice >> > code removal. >> >> I have never really looked into radio tap so I don't want to make any >> statements here. If the 11n part can be done in mac80211 why not. > > hi! > > i'm currently working on a patch removing iwl's own radiotap header. while > doing that i noticed, that we currently don't have a field in > ieee80211_rx_status for the modulation used. for example iwl knows if the > frame was demodulated using CCK (RX_RES_PHY_FLAGS_MOD_CCK_MSK), thus it's > able to differentiate between B and G modes. in mac80211 we can't do that > right now. > > i guess we could deduct the modulation from the rate > > 1, 2, 5.5, 11 -> CCK > everything else -> OFDM > > but i'm not sure if this is always true. is there any hardware that also does > PBCC? also what about CCK-OFDM modes (b/g interoperability), do we have any > way to identify these? > > what do you think, should we explicitly make a modulation field in rx_status > or should we implicitly deduct the modulation from the rates? I believe you can safely assume CCK from rate in WiFi. Both PBCC and CCK/OFDM are optional by the spec meaning nobody really going to implement. I suggest to focus on the main pass and deal with the corner cases only if needed. Tomas > > bruno > -- 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
