The NIC/firmware initialises the initial RTS/CTS rate to something
high, like OFDM48. That's not going to be very reliable.
It's not a problem right now as we program in the RTS/CTS value
to use in the TX descriptor setup path based on the control rate
for the given frame TX rate, and like the INIDATA/driver rate
stuff in the TX descriptor, the TX descriptor RTS/CTS rate overrides
the INIRTS rate.
However when it's time to flip on firmware based rate control,
the initial rate needs to not be OFDM48. Yes, the firmware and
hardware does have some rate retry schedule for RTS/CTS frames,
but there's no point in wasting short retries trying to do OFDM48
based RTS/CTS setup.
Add some warning logging if there are no basic or RTS/CTS rates
available, and leave things at default. If this happens in
production for someone then it would be good to know and what
the rate mask was.
Locally tested:
- RTL8192CU, STA mode (with/without firmware rate control enabled locally)