linux-kernel - [RFC PATCH 2/5] Altered regmap_X_X_write functions to account for padding bits

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-Id: <20211217201758.1743750-3-linuxkernel@fbautosys.co.uk>
Date:   Fri, 17 Dec 2021 20:17:55 +0000
From:   linuxkernel@...utosys.co.uk
To:     linux-kernel@...r.kernel.org
Cc:     broonie@...nel.org
Subject: [RFC PATCH 2/5] Altered regmap_X_X_write functions to account for padding bits

From: Christopher Tyerman <c.tyerman@...ebladeautomationsystems.co.uk>

	modified:   drivers/base/regmap/regmap.c

Signed-off-by: Christopher Tyerman <c.tyerman@...ebladeautomationsystems.co.uk>
---
 drivers/base/regmap/regmap.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 05c104659381..07d6d804c4b9 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -232,42 +232,52 @@ static void regmap_format_2_6_write(struct regmap *map,
 				     unsigned int reg, unsigned int val)
 {
 	u8 *out = map->work_buf;
+	u8 shift = map->reg_shift;
 
-	*out = (reg << 6) | val;
+	*out = (reg << (6 + shift) | val);
 }
 
 static void regmap_format_4_12_write(struct regmap *map,
 				     unsigned int reg, unsigned int val)
 {
+	u8 shift = map->reg_shift;
 	__be16 *out = map->work_buf;
-	*out = cpu_to_be16((reg << 12) | val);
+
+	*out = cpu_to_be16((reg << (12 + shift)) | val);
 }
 
 static void regmap_format_7_9_write(struct regmap *map,
 				    unsigned int reg, unsigned int val)
 {
+	u8 shift = map->reg_shift;
 	__be16 *out = map->work_buf;
-	*out = cpu_to_be16((reg << 9) | val);
+
+	*out = cpu_to_be16((reg << (9 + shift)) | val);
 }
 
 static void regmap_format_7_17_write(struct regmap *map,
 				    unsigned int reg, unsigned int val)
 {
+	u8 shift = map->reg_shift;
 	u8 *out = map->work_buf;
 
 	out[2] = val;
 	out[1] = val >> 8;
-	out[0] = (val >> 16) | (reg << 1);
+	out[0] = (val >> 16) | (reg << (1 + shift));
 }
 
 static void regmap_format_10_14_write(struct regmap *map,
 				    unsigned int reg, unsigned int val)
 {
+	u8 shift = map->reg_shift;
 	u8 *out = map->work_buf;
 
 	out[2] = val;
-	out[1] = (val >> 8) | (reg << 6);
-	out[0] = reg >> 2;
+	out[1] = (val >> 8) | (reg << (6 + shift));
+	if (shift <= 2)
+		out[0] = reg >> (2 - shift);
+	else
+		out[0] = reg << shift;
 }
 
 static void regmap_format_8(void *buf, unsigned int val, unsigned int shift)
-- 
2.25.1