[PATCH rtw-next v4 2/3] fi: rtw88: rtw8822c: Convert DAC IQ calibration path to signed math

Convert the temporary stack arrays 'iv' and 'qv' from u32 to s32.
Update all internal function signatures to accept s32 pointers and
handle signed values natively.

Use sign_extend32() combined with FIELD_GET() to properly interpret
the 10-bit hardware values as signed integers. This allows flattening
the complex nested unsigned boundary conditions in
rtw8822c_dac_iq_check() into a simple amplitude boundary check. Ensure
rtw8822c_dac_iq_offset() properly maps the signed average back to a
10-bit unsigned format expected by the hardware registers.

Signed-off-by: Arsenii Pashchenko <[email protected]>
---
 drivers/net/wireless/realtek/rtw88/rtw8822c.c | 127 +++++-------------
 1 file changed, 36 insertions(+), 91 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtw88/rtw8822c.c b/drivers/net/wireless/realtek/rtw88/rtw8822c.c
index 3bf9291d6..6ad90d321 100644
--- a/drivers/net/wireless/realtek/rtw88/rtw8822c.c
+++ b/drivers/net/wireless/realtek/rtw88/rtw8822c.c
@@ -153,49 +153,14 @@ static void rtw8822c_dac_restore_reg(struct rtw_dev *rtwdev,
 	}
 }
 
-static void rtw8822c_rf_minmax_cmp(struct rtw_dev *rtwdev, u32 value,
-				   u32 *min, u32 *max)
+static void __rtw8822c_dac_iq_sort(struct rtw_dev *rtwdev, s32 *v1, s32 *v2)
 {
-	if (value >= 0x200) {
-		if (*min >= 0x200) {
-			if (*min > value)
-				*min = value;
-		} else {
-			*min = value;
-		}
-		if (*max >= 0x200) {
-			if (*max < value)
-				*max = value;
-		}
-	} else {
-		if (*min < 0x200) {
-			if (*min > value)
-				*min = value;
-		}
-
-		if (*max  >= 0x200) {
-			*max = value;
-		} else {
-			if (*max < value)
-				*max = value;
-		}
-	}
-}
-
-static void __rtw8822c_dac_iq_sort(struct rtw_dev *rtwdev, u32 *v1, u32 *v2)
-{
-	if (*v1 >= 0x200 && *v2 >= 0x200) {
-		if (*v1 > *v2)
-			swap(*v1, *v2);
-	} else if (*v1 < 0x200 && *v2 < 0x200) {
-		if (*v1 > *v2)
-			swap(*v1, *v2);
-	} else if (*v1 < 0x200 && *v2 >= 0x200) {
+	if (*v1 > *v2)
 		swap(*v1, *v2);
-	}
+
 }
 
-static void rtw8822c_dac_iq_sort(struct rtw_dev *rtwdev, u32 *iv, u32 *qv)
+static void rtw8822c_dac_iq_sort(struct rtw_dev *rtwdev, s32 *iv, s32 *qv)
 {
 	u32 i, j;
 
@@ -207,30 +172,16 @@ static void rtw8822c_dac_iq_sort(struct rtw_dev *rtwdev, u32 *iv, u32 *qv)
 	}
 }
 
-static void rtw8822c_dac_iq_offset(struct rtw_dev *rtwdev, u32 *vec, u32 *val)
+static u32 rtw8822c_dac_iq_offset(struct rtw_dev *rtwdev, s32 *vec)
 {
-	u32 p, m, t, i;
+	s32 sum = 0;
 
-	m = 0;
-	p = 0;
-	for (i = 10; i < DACK_SN_8822C - 10; i++) {
-		if (vec[i] > 0x200)
-			m = (0x400 - vec[i]) + m;
-		else
-			p = vec[i] + p;
-	}
+	for (u32 i = 10; i < DACK_SN_8822C - 10; i++)
+		sum += vec[i];
 
-	if (p > m) {
-		t = p - m;
-		t = t / (DACK_SN_8822C - 20);
-	} else {
-		t = m - p;
-		t = t / (DACK_SN_8822C - 20);
-		if (t != 0x0)
-			t = 0x400 - t;
-	}
+	s32 avg = sum / (DACK_SN_8822C - 20);
 
-	*val = t;
+	return avg >= 0 ? (u32)avg : (u32)(0x400 + avg);
 }
 
 static u32 rtw8822c_get_path_write_addr(u8 path)
@@ -271,20 +222,18 @@ static u32 rtw8822c_get_path_read_addr(u8 path)
 	return base_addr;
 }
 
-static bool rtw8822c_dac_iq_check(struct rtw_dev *rtwdev, u32 value)
+static bool rtw8822c_dac_iq_check(struct rtw_dev *rtwdev, s32 value)
 {
-	bool ret = true;
 
-	if ((value >= 0x200 && (0x400 - value) > 0x64) ||
-	    (value < 0x200 && value > 0x64)) {
-		ret = false;
+	if (value > 100 || value < -100) {
 		rtw_dbg(rtwdev, RTW_DBG_RFK, "[DACK] Error overflow\n");
+		return false;
 	}
 
-	return ret;
+	return true;
 }
 
-static void rtw8822c_dac_cal_iq_sample(struct rtw_dev *rtwdev, u32 *iv, u32 *qv)
+static void rtw8822c_dac_cal_iq_sample(struct rtw_dev *rtwdev, s32 *iv, s32 *qv)
 {
 	u32 temp;
 	int i = 0, cnt = 0;
@@ -292,8 +241,8 @@ static void rtw8822c_dac_cal_iq_sample(struct rtw_dev *rtwdev, u32 *iv, u32 *qv)
 	while (i < DACK_SN_8822C && cnt < 10000) {
 		cnt++;
 		temp = rtw_read32(rtwdev, 0x2dbc);
-		iv[i] = FIELD_GET(RTW8822C_DAC_IV_MASK, temp);
-		qv[i] = FIELD_GET(RTW8822C_DAC_QV_MASK, temp);
+		iv[i] = FIELD_GET_SIGNED(RTW8822C_DAC_IV_MASK, temp);
+		qv[i] = FIELD_GET_SIGNED(RTW8822C_DAC_QV_MASK, temp);
 
 		if (rtw8822c_dac_iq_check(rtwdev, iv[i]) &&
 		    rtw8822c_dac_iq_check(rtwdev, qv[i]))
@@ -305,10 +254,10 @@ static void rtw8822c_dac_cal_iq_search(struct rtw_dev *rtwdev,
 				       u32 *iv, u32 *qv,
 				       u32 *i_value, u32 *q_value)
 {
-	u32 i_max = 0, q_max = 0, i_min = 0, q_min = 0;
+	s32 i_max = 0, q_max = 0, i_min = 0, q_min = 0;
 	u32 i_delta, q_delta;
 	u32 temp;
-	int i, cnt = 0;
+	u32 i, cnt = 0;
 
 	do {
 		i_min = iv[0];
@@ -316,23 +265,19 @@ static void rtw8822c_dac_cal_iq_search(struct rtw_dev *rtwdev,
 		q_min = qv[0];
 		q_max = qv[0];
 		for (i = 0; i < DACK_SN_8822C; i++) {
-			rtw8822c_rf_minmax_cmp(rtwdev, iv[i], &i_min, &i_max);
-			rtw8822c_rf_minmax_cmp(rtwdev, qv[i], &q_min, &q_max);
+			if (iv[i] < i_min)
+				i_min = iv[i];
+			if (iv[i] > i_max)
+				i_max = iv[i];
+			if (qv[i] < q_min)
+				q_min = qv[i];
+			if (qv[i] > q_max)
+				q_max = qv[i];
 		}
 
-		if (i_max < 0x200 && i_min < 0x200)
-			i_delta = i_max - i_min;
-		else if (i_max >= 0x200 && i_min >= 0x200)
-			i_delta = i_max - i_min;
-		else
-			i_delta = i_max + (0x400 - i_min);
+		i_delta = i_max - i_min;
+		q_delta = q_max - q_min;
 
-		if (q_max < 0x200 && q_min < 0x200)
-			q_delta = q_max - q_min;
-		else if (q_max >= 0x200 && q_min >= 0x200)
-			q_delta = q_max - q_min;
-		else
-			q_delta = q_max + (0x400 - q_min);
 
 		rtw_dbg(rtwdev, RTW_DBG_RFK,
 			"[DACK] i: min=0x%08x, max=0x%08x, delta=0x%08x\n",
@@ -345,24 +290,24 @@ static void rtw8822c_dac_cal_iq_search(struct rtw_dev *rtwdev,
 
 		if (i_delta > 5 || q_delta > 5) {
 			temp = rtw_read32(rtwdev, 0x2dbc);
-			iv[0] = FIELD_GET(RTW8822C_DAC_IV_MASK, temp);
-			qv[0] = FIELD_GET(RTW8822C_DAC_QV_MASK, temp);
+			iv[0] = FIELD_GET_SIGNED(RTW8822C_DAC_IV_MASK, temp);
+			qv[0] = FIELD_GET_SIGNED(RTW8822C_DAC_QV_MASK, temp);
 			temp = rtw_read32(rtwdev, 0x2dbc);
-			iv[DACK_SN_8822C - 1] = FIELD_GET(RTW8822C_DAC_IV_MASK, temp);
-			qv[DACK_SN_8822C - 1] = FIELD_GET(RTW8822C_DAC_QV_MASK, temp);
+			iv[DACK_SN_8822C - 1] = FIELD_GET_SIGNED(RTW8822C_DAC_IV_MASK, temp);
+			qv[DACK_SN_8822C - 1] = FIELD_GET_SIGNED(RTW8822C_DAC_QV_MASK, temp);
 		} else {
 			break;
 		}
 	} while (cnt++ < 100);
 
-	rtw8822c_dac_iq_offset(rtwdev, iv, i_value);
-	rtw8822c_dac_iq_offset(rtwdev, qv, q_value);
+	*i_value = rtw8822c_dac_iq_offset(rtwdev, iv);
+	*q_value = rtw8822c_dac_iq_offset(rtwdev, qv);
 }
 
 static void rtw8822c_dac_cal_rf_mode(struct rtw_dev *rtwdev,
 				     u32 *i_value, u32 *q_value)
 {
-	u32 iv[DACK_SN_8822C], qv[DACK_SN_8822C];
+	s32 iv[DACK_SN_8822C], qv[DACK_SN_8822C];
 	u32 rf_a, rf_b;
 
 	rf_a = rtw_read_rf(rtwdev, RF_PATH_A, 0x0, RFREG_MASK);
-- 
2.55.0