[PATCH 5/7] wifi: rtw89: 8852c: disable ER SU when 4x HE-LTF and 0.8 GI capability differ

[Ping-Ke Shih <pkshih@xxxxxxxxxxx>]

From: Kuan-Chung Chen <damon.chen@xxxxxxxxxxx>

Since hardware only has single one register for HE-LTF setting,
to prevent interoperability issues, 8852CE disables ER SU when
the AP can handle SU/MU with 4x HE-LTF and 0.8 GI, but does
not support ER SU with the same settings.

Signed-off-by: Kuan-Chung Chen <damon.chen@xxxxxxxxxxx>
Signed-off-by: Ping-Ke Shih <pkshih@xxxxxxxxxxx>
---
 drivers/net/wireless/realtek/rtw89/core.c | 24 ++++++++++++++++++-----
 drivers/net/wireless/realtek/rtw89/core.h | 10 ++++++++++
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtw89/core.c b/drivers/net/wireless/realtek/rtw89/core.c
index ee6ad185135c..f848185e2ced 100644
--- a/drivers/net/wireless/realtek/rtw89/core.c
+++ b/drivers/net/wireless/realtek/rtw89/core.c
@@ -3844,6 +3844,22 @@ int rtw89_core_sta_link_disconnect(struct rtw89_dev *rtwdev,
 	return ret;
 }
 
+static bool rtw89_sta_link_can_er(struct rtw89_dev *rtwdev,
+				  struct ieee80211_bss_conf *bss_conf,
+				  struct ieee80211_link_sta *link_sta)
+{
+	if (!bss_conf->he_support ||
+	    bss_conf->he_oper.params & IEEE80211_HE_OPERATION_ER_SU_DISABLE)
+		return false;
+
+	if (rtwdev->chip->chip_id == RTL8852C &&
+	    rtw89_sta_link_has_su_mu_4xhe08(link_sta) &&
+	    !rtw89_sta_link_has_er_su_4xhe08(link_sta))
+		return false;
+
+	return true;
+}
+
 int rtw89_core_sta_link_assoc(struct rtw89_dev *rtwdev,
 			      struct rtw89_vif_link *rtwvif_link,
 			      struct rtw89_sta_link *rtwsta_link)
@@ -3854,12 +3870,11 @@ int rtw89_core_sta_link_assoc(struct rtw89_dev *rtwdev,
 									 rtwsta_link);
 	const struct rtw89_chan *chan = rtw89_chan_get(rtwdev,
 						       rtwvif_link->chanctx_idx);
+	struct ieee80211_link_sta *link_sta;
 	int ret;
 
 	if (vif->type == NL80211_IFTYPE_AP || sta->tdls) {
 		if (sta->tdls) {
-			struct ieee80211_link_sta *link_sta;
-
 			rcu_read_lock();
 
 			link_sta = rtw89_sta_rcu_dereference_link(rtwsta_link, true);
@@ -3910,9 +3925,8 @@ int rtw89_core_sta_link_assoc(struct rtw89_dev *rtwdev,
 		rcu_read_lock();
 
 		bss_conf = rtw89_vif_rcu_dereference_link(rtwvif_link, true);
-		if (bss_conf->he_support &&
-		    !(bss_conf->he_oper.params & IEEE80211_HE_OPERATION_ER_SU_DISABLE))
-			rtwsta_link->er_cap = true;
+		link_sta = rtw89_sta_rcu_dereference_link(rtwsta_link, true);
+		rtwsta_link->er_cap = rtw89_sta_link_can_er(rtwdev, bss_conf, link_sta);
 
 		rcu_read_unlock();
 
diff --git a/drivers/net/wireless/realtek/rtw89/core.h b/drivers/net/wireless/realtek/rtw89/core.h
index 15967978bf4a..c2b5eeb4a4f1 100644
--- a/drivers/net/wireless/realtek/rtw89/core.h
+++ b/drivers/net/wireless/realtek/rtw89/core.h
@@ -6885,6 +6885,16 @@ bool rtw89_sta_link_has_su_mu_4xhe08(struct ieee80211_link_sta *link_sta)
 	return false;
 }
 
+static inline
+bool rtw89_sta_link_has_er_su_4xhe08(struct ieee80211_link_sta *link_sta)
+{
+	if (link_sta->he_cap.he_cap_elem.phy_cap_info[8] &
+	    IEEE80211_HE_PHY_CAP8_HE_ER_SU_PPDU_4XLTF_AND_08_US_GI)
+		return true;
+
+	return false;
+}
+
 static inline struct rtw89_fw_suit *rtw89_fw_suit_get(struct rtw89_dev *rtwdev,
 						      enum rtw89_fw_type type)
 {
-- 
2.25.1