wifi: mac80211: introduce 'channel request'

For channel contexts, mac80211 currently uses the cfg80211
chandef struct (control channel, center freq(s), width) to
define towards drivers and internally how these behave. In
fact, there are _two_ such structs used, where the min_def
can reduce bandwidth according to the stations connected.

Unfortunately,  with EHT this is longer be sufficient,  at
least not for all hardware.  EHT requires that non-AP STAs
that are connected to an AP with a lower bandwidth than it
(the AP) advertises (e.g. 160 MHz STA connected to 320 MHz
AP) still be able to receive downlink OFDMA and respond to
trigger frames for uplink OFDMA  that specify the position
and bandwidth  for the non-AP STA  relative to the channel
the AP is using.  Therefore, they need to be aware of this,
and at least for some hardware (e.g. Intel) this awareness
is in the hardware. As a result, use of the "same" channel
may need to be split over  two channel contexts where they
differ by the AP being used.

As a first step,  introduce a concept of a channel request
('chanreq') for each interface,  to control the context it
requests.   This step does nothing but reorganise the code,
so that later the AP's chandef can be added to the request
in order to handle the EHT case described above.

Link: https://msgid.link/20240129194108.2e88e48bd2e9.I4256183debe975c5ed71621611206fdbb69ba330@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/mac80211/ocb.c b/net/mac80211/ocb.c
index 449af4e1cca4..2dd4a2196af4 100644
--- a/net/mac80211/ocb.c
+++ b/net/mac80211/ocb.c
@@ -168,6 +168,7 @@ void ieee80211_ocb_setup_sdata(struct ieee80211_sub_if_data *sdata)
 int ieee80211_ocb_join(struct ieee80211_sub_if_data *sdata,
 		       struct ocb_setup *setup)
 {
+	struct ieee80211_chan_req chanreq = { .oper = setup->chandef };
 	struct ieee80211_local *local = sdata->local;
 	struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
 	u64 changed = BSS_CHANGED_OCB | BSS_CHANGED_BSSID;
@@ -182,7 +183,7 @@ int ieee80211_ocb_join(struct ieee80211_sub_if_data *sdata,
 	sdata->deflink.smps_mode = IEEE80211_SMPS_OFF;
 	sdata->deflink.needed_rx_chains = sdata->local->rx_chains;
 
-	err = ieee80211_link_use_channel(&sdata->deflink, &setup->chandef,
+	err = ieee80211_link_use_channel(&sdata->deflink, &chanreq,
 					 IEEE80211_CHANCTX_SHARED);
 	if (err)
 		return err;