linux-kernel - [PATCH 2/2] hwmon: (chipcap2) Switch to guard() for mutext handling

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

Message-Id: <20241121-chipcap_no_iio-v1-2-6c157848a36f@gmail.com>
Date: Thu, 21 Nov 2024 22:44:56 +0100
From: Javier Carrasco <javier.carrasco.cruz@...il.com>
To: Jean Delvare <jdelvare@...e.com>, Guenter Roeck <linux@...ck-us.net>
Cc: linux-kernel@...r.kernel.org, linux-hwmon@...r.kernel.org, 
 Javier Carrasco <javier.carrasco.cruz@...il.com>
Subject: [PATCH 2/2] hwmon: (chipcap2) Switch to guard() for mutext
 handling

Switch to guard() for mutex handling to simplify the code, getting rid
of the 'ret = x, break; return ret;' construct and returning the result
of the operation instead.

Signed-off-by: Javier Carrasco <javier.carrasco.cruz@...il.com>
---
 drivers/hwmon/chipcap2.c | 63 ++++++++++++++----------------------------------
 1 file changed, 18 insertions(+), 45 deletions(-)

diff --git a/drivers/hwmon/chipcap2.c b/drivers/hwmon/chipcap2.c
index edf454474f11..9d071f7ca9d2 100644
--- a/drivers/hwmon/chipcap2.c
+++ b/drivers/hwmon/chipcap2.c
@@ -13,6 +13,7 @@
 
 #include <linux/bitfield.h>
 #include <linux/bits.h>
+#include <linux/cleanup.h>
 #include <linux/completion.h>
 #include <linux/delay.h>
 #include <linux/hwmon.h>
@@ -556,55 +557,40 @@ static int cc2_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
 		    int channel, long *val)
 {
 	struct cc2_data *data = dev_get_drvdata(dev);
-	int ret = 0;
 
-	mutex_lock(&data->dev_access_lock);
+	guard(mutex)(&data->dev_access_lock);
 
 	switch (type) {
 	case hwmon_temp:
-		ret = cc2_measurement(data, type, val);
-		break;
+		return cc2_measurement(data, type, val);
 	case hwmon_humidity:
 		switch (attr) {
 		case hwmon_humidity_input:
-			ret = cc2_measurement(data, type, val);
-			break;
+			return cc2_measurement(data, type, val);
 		case hwmon_humidity_min:
-			ret = cc2_get_reg_val(data, CC2_R_ALARM_L_ON, val);
-			break;
+			return cc2_get_reg_val(data, CC2_R_ALARM_L_ON, val);
 		case hwmon_humidity_min_hyst:
-			ret = cc2_get_reg_val(data, CC2_R_ALARM_L_OFF, val);
-			break;
+			return cc2_get_reg_val(data, CC2_R_ALARM_L_OFF, val);
 		case hwmon_humidity_max:
-			ret = cc2_get_reg_val(data, CC2_R_ALARM_H_ON, val);
-			break;
+			return cc2_get_reg_val(data, CC2_R_ALARM_H_ON, val);
 		case hwmon_humidity_max_hyst:
-			ret = cc2_get_reg_val(data, CC2_R_ALARM_H_OFF, val);
-			break;
+			return cc2_get_reg_val(data, CC2_R_ALARM_H_OFF, val);
 		case hwmon_humidity_min_alarm:
-			ret = cc2_humidity_min_alarm_status(data, val);
-			break;
+			return cc2_humidity_min_alarm_status(data, val);
 		case hwmon_humidity_max_alarm:
-			ret = cc2_humidity_max_alarm_status(data, val);
-			break;
+			return cc2_humidity_max_alarm_status(data, val);
 		default:
-			ret = -EOPNOTSUPP;
+			return -EOPNOTSUPP;
 		}
-		break;
 	default:
-		ret = -EOPNOTSUPP;
+		return -EOPNOTSUPP;
 	}
-
-	mutex_unlock(&data->dev_access_lock);
-
-	return ret;
 }
 
 static int cc2_write(struct device *dev, enum hwmon_sensor_types type, u32 attr,
 		     int channel, long val)
 {
 	struct cc2_data *data = dev_get_drvdata(dev);
-	int ret;
 	u16 arg;
 	u8 cmd;
 
@@ -614,41 +600,28 @@ static int cc2_write(struct device *dev, enum hwmon_sensor_types type, u32 attr,
 	if (val < 0 || val > CC2_RH_MAX)
 		return -EINVAL;
 
-	mutex_lock(&data->dev_access_lock);
+	guard(mutex)(&data->dev_access_lock);
 
 	switch (attr) {
 	case hwmon_humidity_min:
 		cmd = CC2_W_ALARM_L_ON;
 		arg = cc2_rh_to_reg(val);
-		ret = cc2_write_reg(data, cmd, arg);
-		break;
-
+		return cc2_write_reg(data, cmd, arg);
 	case hwmon_humidity_min_hyst:
 		cmd = CC2_W_ALARM_L_OFF;
 		arg = cc2_rh_to_reg(val);
-		ret = cc2_write_reg(data, cmd, arg);
-		break;
-
+		return cc2_write_reg(data, cmd, arg);
 	case hwmon_humidity_max:
 		cmd = CC2_W_ALARM_H_ON;
 		arg = cc2_rh_to_reg(val);
-		ret = cc2_write_reg(data, cmd, arg);
-		break;
-
+		return cc2_write_reg(data, cmd, arg);
 	case hwmon_humidity_max_hyst:
 		cmd = CC2_W_ALARM_H_OFF;
 		arg = cc2_rh_to_reg(val);
-		ret = cc2_write_reg(data, cmd, arg);
-		break;
-
+		return cc2_write_reg(data, cmd, arg);
 	default:
-		ret = -EOPNOTSUPP;
-		break;
+		return -EOPNOTSUPP;
 	}
-
-	mutex_unlock(&data->dev_access_lock);
-
-	return ret;
 }
 
 static int cc2_request_ready_irq(struct cc2_data *data, struct device *dev)

-- 
2.43.0