[PATCH wireless-next v2 3/4] wifi: rtw88: rtw8822c: switch to the kernel's sort() library

[Arsenii Pashchenko <ulijg308@gmail.com>]

Replace the custom, nested bubble-sort logic in rtw8822c_dac_iq_sort()
and __rtw8822c_dac_iq_sort() with a call to the kernel's optimized
heapsort implementation.

Implement a concise, localized s32 comparator. Since the previous
patch already guarantees that input values are properly sign-extended
into signed arrays, the custom circular index sorting rules completely
disappear, trimming down lines of code.

Signed-off-by: Arsenii Pashchenko <ulijg308@gmail.com>
---
 drivers/net/wireless/realtek/rtw88/rtw8822c.c | 28 ++++++-------------
 1 file changed, 8 insertions(+), 20 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtw88/rtw8822c.c b/drivers/net/wireless/realtek/rtw88/rtw8822c.c
index d06986d09..642ac2e2b 100644
--- a/drivers/net/wireless/realtek/rtw88/rtw8822c.c
+++ b/drivers/net/wireless/realtek/rtw88/rtw8822c.c
@@ -4,6 +4,7 @@
 
 #include <linux/module.h>
 #include <linux/bitops.h>
+#include <linux/sort.h>
 #include "main.h"
 #include "coex.h"
 #include "fw.h"
@@ -186,31 +187,18 @@ static void rtw8822c_rf_minmax_cmp(struct rtw_dev *rtwdev, s32 value_s32,
 	}
 }
 
-static void __rtw8822c_dac_iq_sort(struct rtw_dev *rtwdev, s32 *v1_s32, s32 *v2_s32)
+static int rtw8822c_dac_iq_cmp_s32(const void *a, const void *b)
 {
-	u32 *v1 = (u32 *)v1_s32;
-	u32 *v2 = (u32 *)v2_s32;
-	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) {
-		swap(*v1, *v2);
-	}
+	s32 va = *(const s32 *)a;
+	s32 vb = *(const s32 *)b;
+
+	return (va > vb) - (va < vb);
 }
 
 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]);
-		}
-	}
+	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);
 }
 
 static void rtw8822c_dac_iq_offset(struct rtw_dev *rtwdev, s32 *vec_s32, u32 *val)
-- 
2.55.0