hwmon: (max1619) Improve chip detection code

Bail out immediately if reading any of the registers used for chip detection fails, or if it returns an unexpected value. Drop all log messages from detection code. Reviewed-by: Tzung-Bi Shih <[email protected]> Signed-off-by: Guenter Roeck <[email protected]>
wafgo · Jul 31, 2024 · 90368fa · 90368fa
1 parent 13047eb
commit 90368fa
Showing 1 changed file with 14 additions and 18 deletions.
diff --git a/drivers/hwmon/max1619.c b/drivers/hwmon/max1619.c
@@ -260,31 +260,27 @@ static int max1619_detect(struct i2c_client *client,
 			  struct i2c_board_info *info)
 {
 	struct i2c_adapter *adapter = client->adapter;
-	u8 reg_config, reg_convrate, reg_status, man_id, chip_id;
+	int regval;
 
 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 		return -ENODEV;
 
-	/* detection */
-	reg_config = i2c_smbus_read_byte_data(client, MAX1619_REG_CONFIG);
-	reg_convrate = i2c_smbus_read_byte_data(client, MAX1619_REG_CONVRATE);
-	reg_status = i2c_smbus_read_byte_data(client, MAX1619_REG_STATUS);
-	if ((reg_config & 0x03) != 0x00
-	 || reg_convrate > 0x07 || (reg_status & 0x61) != 0x00) {
-		dev_dbg(&adapter->dev, "MAX1619 detection failed at 0x%02x\n",
-			client->addr);
+	regval = i2c_smbus_read_byte_data(client, MAX1619_REG_CONFIG);
+	if (regval < 0 || (regval & 0x03))
+		return -ENODEV;
+	regval = i2c_smbus_read_byte_data(client, MAX1619_REG_CONVRATE);
+	if (regval < 0 || regval > 0x07)
+		return -ENODEV;
+	regval = i2c_smbus_read_byte_data(client, MAX1619_REG_STATUS);
+	if (regval < 0 || (regval & 0x61))
 		return -ENODEV;
-	}
 
-	/* identification */
-	man_id = i2c_smbus_read_byte_data(client, MAX1619_REG_MAN_ID);
-	chip_id = i2c_smbus_read_byte_data(client, MAX1619_REG_CHIP_ID);
-	if (man_id != 0x4D || chip_id != 0x04) {
-		dev_info(&adapter->dev,
-			 "Unsupported chip (man_id=0x%02X, chip_id=0x%02X).\n",
-			 man_id, chip_id);
+	regval = i2c_smbus_read_byte_data(client, MAX1619_REG_MAN_ID);
+	if (regval != 0x4d)
+		return -ENODEV;
+	regval = i2c_smbus_read_byte_data(client, MAX1619_REG_CHIP_ID);
+	if (regval != 0x04)
 		return -ENODEV;
-	}
 
 	strscpy(info->type, "max1619", I2C_NAME_SIZE);