[PATCH rtw-next v5 3/3] wifi: rtw88: rtw8822c: Replace custom DAC IQ sorting with kernel sort

Replace the custom, nested bubble-sort logic in the calibration loop
with direct calls to the kernel's optimized heapsort implementation
inside rtw8822c_dac_cal_iq_search().

Implement a safe, overflow-proof s32 comparator using the subtraction
of relationals pattern. Since the input values are already properly
sign-extended into signed arrays, the custom circular index sorting
rules and helper functions completely disappear, reducing lines of code.

Signed-off-by: Arsenii Pashchenko <[email protected]>
---
 drivers/net/wireless/realtek/rtw88/rtw8822c.c | 24 +++++++------------
 1 file changed, 8 insertions(+), 16 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtw88/rtw8822c.c b/drivers/net/wireless/realtek/rtw88/rtw8822c.c
index 6ad90d321..0140f2e64 100644
--- a/drivers/net/wireless/realtek/rtw88/rtw8822c.c
+++ b/drivers/net/wireless/realtek/rtw88/rtw8822c.c
@@ -3,6 +3,7 @@
  */
 
 #include <linux/module.h>
+#include <linux/sort.h>
 #include "main.h"
 #include "coex.h"
 #include "fw.h"
@@ -153,24 +154,14 @@ static void rtw8822c_dac_restore_reg(struct rtw_dev *rtwdev,
 	}
 }
 
-static void __rtw8822c_dac_iq_sort(struct rtw_dev *rtwdev, s32 *v1, s32 *v2)
+static int rtw8822c_dac_iq_cmp_s32(const void *a, const void *b)
 {
-	if (*v1 > *v2)
-		swap(*v1, *v2);
+	s32 val_a = *(const s32 *)a;
+	s32 val_b = *(const s32 *)b;
 
+	return (val_a > val_b) - (val_a < val_b);
 }
 
-static void rtw8822c_dac_iq_sort(struct rtw_dev *rtwdev, s32 *iv, s32 *qv)
-{
-	u32 i, j;
-
-	for (i = 0; i < DACK_SN_8822C - 1; i++) {
-		for (j = 0; j < (DACK_SN_8822C - 1 - i) ; j++) {
-			__rtw8822c_dac_iq_sort(rtwdev, &iv[j], &iv[j + 1]);
-			__rtw8822c_dac_iq_sort(rtwdev, &qv[j], &qv[j + 1]);
-		}
-	}
-}
 
 static u32 rtw8822c_dac_iq_offset(struct rtw_dev *rtwdev, s32 *vec)
 {
@@ -251,7 +242,7 @@ static void rtw8822c_dac_cal_iq_sample(struct rtw_dev *rtwdev, s32 *iv, s32 *qv)
 }
 
 static void rtw8822c_dac_cal_iq_search(struct rtw_dev *rtwdev,
-				       u32 *iv, u32 *qv,
+				       s32 *iv, s32 *qv,
 				       u32 *i_value, u32 *q_value)
 {
 	s32 i_max = 0, q_max = 0, i_min = 0, q_min = 0;
@@ -286,7 +277,8 @@ static void rtw8822c_dac_cal_iq_search(struct rtw_dev *rtwdev,
 			"[DACK] q: min=0x%08x, max=0x%08x, delta=0x%08x\n",
 			q_min, q_max, q_delta);
 
-		rtw8822c_dac_iq_sort(rtwdev, iv, qv);
+		sort(iv, DACK_SN_8822C, sizeof(s32), rtw8822c_dac_iq_cmp_s32, NULL);
+		sort(qv, DACK_SN_8822C, sizeof(s32), rtw8822c_dac_iq_cmp_s32, NULL);
 
 		if (i_delta > 5 || q_delta > 5) {
 			temp = rtw_read32(rtwdev, 0x2dbc);
-- 
2.55.0