the channel width is ni->ni_chw, which is set to the negotiated channel
width. ni->ni_htflags is the capability, rather than the negotiated
value.
Teach both the TX path and the sample rate module about this.
This seems to work fine for STA but not HT/20 AP mode.
Further discussion with net80211 people will need to take place
to ensure that the right flags are set based on the negotiated
capabilities of the remote peer, rather than whatever the local
parameters are.
Sending short-gi frames in 20mhz may work on some chips but
it certainly isn't supported on anything currently supported
by the HAL; and sending HT40 frames in HT20 mode just plain
won't work.
These flags are just plain wrong - they're the node flags from negotiation,
not the configured flags. I'll jump in later on and figure out exactly
what should be done to properly set these two flags when in both STA mode
(ie, what the AP says is possible and what's configured) and AP mode
(ie, where the AP has a configuration, but then negotiates what's possible
with each node, so per-node configuration can and will differ.)
This allows the 11n 2.4ghz/ht20 mode to associate (but perform poorly still)
and exchange MCS rates with atheros reference APs and a Cisco/Linksys
E3000 AP.
correctly:
* pass in whether to allow the hardware to override the duration field
in the main data frame (durupdate_en) - PS_POLL frames in particular
don't have the duration bit overriden;
* there's no rts/cts duration here; that's done elsehwere
The AR5416 and later TX descriptors have new fields for supporting
11n bits (eg 20/40mhz mode, short/long GI) and enabling/disabling
RTS/CTS protection per rate.
These functions will be responsible for initialising the TX descriptors
for the AR5416 and later chips for both HT and legacy frames.
Beacon frames will remain using the non-11n TX descriptor setup for now;
Linux ath9k does much the same.
Note that these functions aren't yet used anywhere; a few more framework
changes are needed before all of the right rate information is available
for TX.