How to find sdata's frequency?

For ath9k, the code below finds a chanctx_conf (and channel), but for ath9k_htc it does not. Any idea for how to find the current operating channel for ath9k_htc?

	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
	if (chanctx_conf)
		channel = chanctx_conf->def.chan;
	else
		channel = NULL;

Thanks,
Ben

Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com