On 2010-07-27 6:19 PM, Luis R. Rodriguez wrote: >> + * @NL80211_ATTR_WIPHY_ANTENNA_TX: Bitmap of allowed antennas for transmitting. >> + * Each bit represents one antenna, starting with antenna 1 at the first >> + * bit. If the bitmap is zero (0), the TX antenna follows RX diversity. > > What about for 802.11n? What if you want to disable TX? Disabling tx shouldn't be handled by the antenna setting, IMHO. >> + * If multiple antennas are selected all selected antennas have to be used >> + * for transmitting (801.11n multiple TX chains). > > I rather call this TX / RX chainmask then. Well, for legacy hardware, these aren't really chains, as there is only one rx and one tx path, just with switching onto multiple antennas. >> + * Drivers may reject configurations they cannot support. >> + * >> + * @NL80211_ATTR_WIPHY_ANTENNA_RX: Bitmap of allowed antennas for receiving. >> + * Each bit represents one antenna, starting with antenna 1 at the first >> + * bit. If multiple antennas are selected in the bitmap, 802.11n devices >> + * should use multiple RX chains on these antennas, while non-802.11n >> + * drivers should use antenna diversity between these antennas. > > What about TX beamforming, and STBC? Disabling one antenna/chain on a two-chain device would naturally disable TxBF and STBC as well, since it limits the number of available chains. The driver should simply act as if the disabled chains didn't exist. > Unless 802.11n is completely dealt with I really prefer this patch to > only address legacy. Otherwise I see sloppyness and inconsistencies on > supporting this feature throughout different drivers. I'd like to > avoid that at all costs on nl80211. What you are trying to address is > legacy antenna setup, not 802.11n RX/TX chainmask dynamic settings so > I'd really try to avoid it unless you really want to address all > aspects of chain configuration for 802.11n and even then what I'm > leading on to say is I think you'll see if you try to address both it > just gets messy. I think 802.11n is already completely dealt with if you treat this as the chainmask on 11n devices. - Felix -- 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
