linux-kernel - [PATCH 13/17] mtd: ssfdc: Replace open-coded parity calculation with parity32()

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Message-Id: <20250223164217.2139331-14-visitorckw@gmail.com>
Date: Mon, 24 Feb 2025 00:42:13 +0800
From: Kuan-Wei Chiu <visitorckw@...il.com>
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	Kuan-Wei Chiu <visitorckw@...il.com>,
	Yu-Chun Lin <eleanor15x@...il.com>
Subject: [PATCH 13/17] mtd: ssfdc: Replace open-coded parity calculation with parity32()

Refactor parity calculations to use the standard parity32() helper.
This change eliminates redundant implementations and improves code
efficiency.

Co-developed-by: Yu-Chun Lin <eleanor15x@...il.com>
Signed-off-by: Yu-Chun Lin <eleanor15x@...il.com>
Signed-off-by: Kuan-Wei Chiu <visitorckw@...il.com>
---
 drivers/mtd/ssfdc.c | 17 ++---------------
 1 file changed, 2 insertions(+), 15 deletions(-)

diff --git a/drivers/mtd/ssfdc.c b/drivers/mtd/ssfdc.c
index 46c01fa2ec46..e7f9e73da644 100644
--- a/drivers/mtd/ssfdc.c
+++ b/drivers/mtd/ssfdc.c
@@ -7,6 +7,7 @@
  * Based on NTFL and MTDBLOCK_RO drivers
  */
 
+#include <linux/bitops.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
@@ -178,20 +179,6 @@ static int read_raw_oob(struct mtd_info *mtd, loff_t offs, uint8_t *buf)
 	return 0;
 }
 
-/* Parity calculator on a word of n bit size */
-static int get_parity(int number, int size)
-{
- 	int k;
-	int parity;
-
-	parity = 1;
-	for (k = 0; k < size; k++) {
-		parity += (number >> k);
-		parity &= 1;
-	}
-	return parity;
-}
-
 /* Read and validate the logical block address field stored in the OOB */
 static int get_logical_address(uint8_t *oob_buf)
 {
@@ -215,7 +202,7 @@ static int get_logical_address(uint8_t *oob_buf)
 			block_address &= 0x7FF;
 			block_address >>= 1;
 
-			if (get_parity(block_address, 10) != parity) {
+			if (parity32(block_address & 0x3ff) == parity) {
 				pr_debug("SSFDC_RO: logical address field%d"
 					"parity error(0x%04X)\n", j+1,
 					block_address);
-- 
2.34.1