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 <tzungbi@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This commit is contained in:
Guenter Roeck 2024-07-26 15:29:40 -07:00
parent 13047ebe63
commit 90368fa397

View File

@ -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);