linux-kernel - [PATCH] hwmon: (lm93) Return error values on read failure

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Message-Id: <20240807181746.508972-1-abhishektamboli9@gmail.com>
Date: Wed,  7 Aug 2024 23:47:46 +0530
From: Abhishek Tamboli <abhishektamboli9@...il.com>
To: jdelvare@...e.com,
	linux@...ck-us.net
Cc: skhan@...uxfoundation.org,
	rbmarliere@...il.com,
	linux-kernel-mentees@...ts.linuxfoundation.org,
	linux-hwmon@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH] hwmon: (lm93) Return error values on read failure

Fix the issue of lm93_read_byte() and lm93_read_word() return 0 on
read failure after retries, which could be confused with valid data.

Address the TODO: what to return in case of error?

Signed-off-by: Abhishek Tamboli <abhishektamboli9@...il.com>
---
 drivers/hwmon/lm93.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/hwmon/lm93.c b/drivers/hwmon/lm93.c
index be4853fad80f..b76f3c1c6297 100644
--- a/drivers/hwmon/lm93.c
+++ b/drivers/hwmon/lm93.c
@@ -798,6 +798,7 @@ static unsigned LM93_ALARMS_FROM_REG(struct block1_t b1)
 static u8 lm93_read_byte(struct i2c_client *client, u8 reg)
 {
 	int value, i;
+	int ret;
 
 	/* retry in case of read errors */
 	for (i = 1; i <= MAX_RETRIES; i++) {
@@ -808,14 +809,14 @@ static u8 lm93_read_byte(struct i2c_client *client, u8 reg)
 			dev_warn(&client->dev,
 				 "lm93: read byte data failed, address 0x%02x.\n",
 				 reg);
+			ret = value;
 			mdelay(i + 3);
 		}
 
 	}
 
-	/* <TODO> what to return in case of error? */
 	dev_err(&client->dev, "lm93: All read byte retries failed!!\n");
-	return 0;
+	return ret;
 }
 
 static int lm93_write_byte(struct i2c_client *client, u8 reg, u8 value)
@@ -836,6 +837,7 @@ static int lm93_write_byte(struct i2c_client *client, u8 reg, u8 value)
 static u16 lm93_read_word(struct i2c_client *client, u8 reg)
 {
 	int value, i;
+	int ret;
 
 	/* retry in case of read errors */
 	for (i = 1; i <= MAX_RETRIES; i++) {
@@ -846,14 +848,14 @@ static u16 lm93_read_word(struct i2c_client *client, u8 reg)
 			dev_warn(&client->dev,
 				 "lm93: read word data failed, address 0x%02x.\n",
 				 reg);
+			ret = value;
 			mdelay(i + 3);
 		}
 
 	}
 
-	/* <TODO> what to return in case of error? */
 	dev_err(&client->dev, "lm93: All read word retries failed!!\n");
-	return 0;
+	return ret;
 }
 
 static int lm93_write_word(struct i2c_client *client, u8 reg, u16 value)
-- 
2.34.1