[RFC PATCH v2 06/13] wifi: mac80211: disallow drivers with HT wider than HE

[Johannes Berg <johannes@sipsolutions.net>]

From: Johannes Berg <johannes.berg@intel.com>

To simplify the code in the next patch, disallow drivers
supporting 40 MHz in HT but not HE, since we'd otherwise
have to track local maximum bandwidth per mode there.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/mac80211/main.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 033a5261ac3a..48e012ee1ae4 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -1115,8 +1115,26 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
 		supp_vht = supp_vht || sband->vht_cap.vht_supported;
 
 		for_each_sband_iftype_data(sband, i, iftd) {
+			u8 he_40_mhz_cap;
+
 			supp_he = supp_he || iftd->he_cap.has_he;
 			supp_eht = supp_eht || iftd->eht_cap.has_eht;
+
+			if (sband->band == NL80211_BAND_2GHZ)
+				he_40_mhz_cap =
+					IEEE80211_HE_PHY_CAP0_CHANNEL_WIDTH_SET_40MHZ_IN_2G;
+			else
+				he_40_mhz_cap =
+					IEEE80211_HE_PHY_CAP0_CHANNEL_WIDTH_SET_40MHZ_80MHZ_IN_5G;
+
+			/* currently no support for HE client where HT has 40 MHz but not HT */
+			if (iftd->he_cap.has_he &&
+			    iftd->types_mask & (BIT(NL80211_IFTYPE_STATION) |
+						BIT(NL80211_IFTYPE_P2P_CLIENT)) &&
+			    sband->ht_cap.ht_supported &&
+			    sband->ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 &&
+			    !(iftd->he_cap.he_cap_elem.phy_cap_info[0] & he_40_mhz_cap))
+				return -EINVAL;
 		}
 
 		/* HT, VHT, HE require QoS, thus >= 4 queues */
-- 
2.42.0