From: Kuan-Chung Chen <damon.chen@realtek.com>
Date: Tue, 21 Oct 2025 13:34:00 +0000 (+0800)
Subject: wifi: rtw89: 8852c: fix ADC oscillation in 160MHz affecting RX performance
X-Git-Tag: v6.19-rc1~170^2~33^2~10^2~68
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a48ae54a67f7a3c05d51ca87877832d4d6ea4639;p=thirdparty%2Fkernel%2Flinux.git

wifi: rtw89: 8852c: fix ADC oscillation in 160MHz affecting RX performance

When operating in 160 MHz, the ADC may oscillate and affect AGC, leading
to unstable RX quality. This issue can be resolved by ensuring proper
RF filter bandwidth switching to avoid ADC oscillation.

Signed-off-by: Kuan-Chung Chen <damon.chen@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20251021133402.15467-7-pkshih@realtek.com
---

diff --git a/drivers/net/wireless/realtek/rtw89/rtw8852c_rfk.c b/drivers/net/wireless/realtek/rtw89/rtw8852c_rfk.c
index e7fd028c5e829..cbee484dee302 100644
--- a/drivers/net/wireless/realtek/rtw89/rtw8852c_rfk.c
+++ b/drivers/net/wireless/realtek/rtw89/rtw8852c_rfk.c
@@ -3987,37 +3987,56 @@ static void _ctrl_ch(struct rtw89_dev *rtwdev, enum rtw89_phy_idx phy,
 	}
 }
 
+static void _set_rxbb_bw(struct rtw89_dev *rtwdev, enum rtw89_rf_path path,
+			 enum rtw89_bandwidth bw)
+{
+	u32 val;
+
+	rtw89_write_rf(rtwdev, path, RR_LUTWE2, RR_LUTWE2_RTXBW, 0x1);
+	rtw89_write_rf(rtwdev, path, RR_LUTWA, RR_LUTWA_M2, 0xa);
+
+	switch (bw) {
+	case RTW89_CHANNEL_WIDTH_20:
+		val = 0x1b;
+		break;
+	case RTW89_CHANNEL_WIDTH_40:
+		val = 0x13;
+		break;
+	case RTW89_CHANNEL_WIDTH_80:
+		val = 0xb;
+		break;
+	case RTW89_CHANNEL_WIDTH_160:
+	default:
+		val = 0x3;
+		break;
+	}
+
+	rtw89_write_rf(rtwdev, path, RR_LUTWD0, RR_LUTWD0_LB, val);
+	rtw89_write_rf(rtwdev, path, RR_LUTWE2, RR_LUTWE2_RTXBW, 0x0);
+}
+
+static void _set_tia_bw(struct rtw89_dev *rtwdev, enum rtw89_rf_path path,
+			enum rtw89_bandwidth bw)
+{
+	if (bw == RTW89_CHANNEL_WIDTH_160)
+		rtw89_write_rf(rtwdev, path, RR_RXBB2, RR_RXBB2_EBW, 0x0);
+	else
+		rtw89_write_rf(rtwdev, path, RR_RXBB2, RR_RXBB2_EBW, 0x2);
+}
+
 static void _rxbb_bw(struct rtw89_dev *rtwdev, enum rtw89_phy_idx phy,
 		     enum rtw89_bandwidth bw)
 {
 	u8 kpath;
 	u8 path;
-	u32 val;
 
 	kpath = _kpath(rtwdev, phy);
 	for (path = 0; path < 2; path++) {
 		if (!(kpath & BIT(path)))
 			continue;
 
-		rtw89_write_rf(rtwdev, path, RR_LUTWE2, RR_LUTWE2_RTXBW, 0x1);
-		rtw89_write_rf(rtwdev, path, RR_LUTWA, RR_LUTWA_M2, 0xa);
-		switch (bw) {
-		case RTW89_CHANNEL_WIDTH_20:
-			val = 0x1b;
-			break;
-		case RTW89_CHANNEL_WIDTH_40:
-			val = 0x13;
-			break;
-		case RTW89_CHANNEL_WIDTH_80:
-			val = 0xb;
-			break;
-		case RTW89_CHANNEL_WIDTH_160:
-		default:
-			val = 0x3;
-			break;
-		}
-		rtw89_write_rf(rtwdev, path, RR_LUTWD0, RR_LUTWD0_LB, val);
-		rtw89_write_rf(rtwdev, path, RR_LUTWE2, RR_LUTWE2_RTXBW, 0x0);
+		_set_rxbb_bw(rtwdev, path, bw);
+		_set_tia_bw(rtwdev, path, bw);
 	}
 }