[PATCH rtw-next 03/16] wifi: rtw89: debug: disable hw_scan for latency-sensitive scenarios

[Ping-Ke Shih <pkshih@realtek.com>]

From: Johnson Tsai <wenjie.tsai@realtek.com>

This helps avoid scan-triggered off-channel activity during
latency-sensitive scenarios.

Add RTW89_DM_HW_SCAN to the disabled_dm bitmap via debugfs and
check it in the hw_scan path. When set, the driver rejects hw_scan
requests and returns -EBUSY.

Signed-off-by: Johnson Tsai <wenjie.tsai@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
---
 drivers/net/wireless/realtek/rtw89/core.h     | 1 +
 drivers/net/wireless/realtek/rtw89/debug.c    | 1 +
 drivers/net/wireless/realtek/rtw89/mac80211.c | 7 +++++++
 3 files changed, 9 insertions(+)

diff --git a/drivers/net/wireless/realtek/rtw89/core.h b/drivers/net/wireless/realtek/rtw89/core.h
index bbcac7cc207c..4a05a8dbb9ed 100644
--- a/drivers/net/wireless/realtek/rtw89/core.h
+++ b/drivers/net/wireless/realtek/rtw89/core.h
@@ -5178,6 +5178,7 @@ enum rtw89_dm_type {
 	RTW89_DM_THERMAL_PROTECT,
 	RTW89_DM_TAS,
 	RTW89_DM_MLO,
+	RTW89_DM_HW_SCAN,
 };
 
 #define RTW89_THERMAL_PROT_LV_MAX 5
diff --git a/drivers/net/wireless/realtek/rtw89/debug.c b/drivers/net/wireless/realtek/rtw89/debug.c
index 7d8d22311018..02386d1d07c6 100644
--- a/drivers/net/wireless/realtek/rtw89/debug.c
+++ b/drivers/net/wireless/realtek/rtw89/debug.c
@@ -4347,6 +4347,7 @@ static const struct rtw89_disabled_dm_info {
 	DM_INFO(THERMAL_PROTECT),
 	DM_INFO(TAS),
 	DM_INFO(MLO),
+	DM_INFO(HW_SCAN),
 };
 
 static ssize_t
diff --git a/drivers/net/wireless/realtek/rtw89/mac80211.c b/drivers/net/wireless/realtek/rtw89/mac80211.c
index 501c3af1da01..9ee2aa225976 100644
--- a/drivers/net/wireless/realtek/rtw89/mac80211.c
+++ b/drivers/net/wireless/realtek/rtw89/mac80211.c
@@ -1241,6 +1241,7 @@ static int rtw89_ops_hw_scan(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 	struct rtw89_dev *rtwdev = hw->priv;
 	struct rtw89_vif *rtwvif = vif_to_rtwvif(vif);
 	struct rtw89_vif_link *rtwvif_link;
+	struct rtw89_hal *hal = &rtwdev->hal;
 	int ret;
 
 	lockdep_assert_wiphy(hw->wiphy);
@@ -1248,6 +1249,12 @@ static int rtw89_ops_hw_scan(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 	if (!RTW89_CHK_FW_FEATURE(SCAN_OFFLOAD, &rtwdev->fw))
 		return 1;
 
+	if (hal->disabled_dm_bitmap & BIT(RTW89_DM_HW_SCAN)) {
+		rtw89_debug(rtwdev, RTW89_DBG_HW_SCAN,
+			    "reject hw scan due to disabled_dm\n");
+		return -EBUSY;
+	}
+
 	if (rtwdev->scanning || rtwvif->offchan)
 		return -EBUSY;
 
-- 
2.25.1