Le 23/01/2025 à 21:25, Andrei Lalaev a écrit :
Add base support for HTU31 temperature and humidity sensor.
Besides temperature and humidity values, the driver also exports a 24-bit
serial number to sysfs.
Signed-off-by: Andrei Lalaev <andrey.lalaev@xxxxxxxxx>
---
...
+static int htu31_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ struct htu31_data *data = dev_get_drvdata(dev);
+ int ret;
+
+ ret = htu31_data_fetch_command(data);
+
Unneeded empty line.
+ if (ret < 0)
+ return ret;
+
+ switch (type) {
+ case hwmon_temp:
+ if (attr != hwmon_temp_input)
+ return -EINVAL;
+
+ *val = data->temperature;
+ break;
+ case hwmon_humidity:
+ if (attr != hwmon_humidity_input)
+ return -EINVAL;
+
+ *val = data->humidity;
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
+}
+
+static int serial_number_populate(struct htu31_data *data)
+{
+ struct i2c_client *client = data->client;
+ u8 read_sn_cmd = HTU31_READ_SERIAL_CMD;
+ u8 sn_buf[HTU31_SERIAL_NUMBER_LEN + HTU31_SERIAL_NUMBER_CRC_LEN];
+ struct i2c_msg msgs[] = {
+ {
+ .addr = client->addr,
+ .flags = 0,
+ .len = 1,
+ .buf = &read_sn_cmd,
+ },
+ {
+ .addr = client->addr,
+ .flags = I2C_M_RD,
+ .len = sizeof(sn_buf),
+ .buf = sn_buf,
+ },
+ };
+ int ret;
+ u8 crc;
+
+ guard(mutex)(&data->i2c_lock);
+
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (ret < 0)
+ return -EIO;
Why not return ret?
+
+ crc = crc8(htu31_crc8_table, sn_buf, HTU31_SERIAL_NUMBER_LEN, HTU31_CRC8_INIT_VAL);
+ if (crc != sn_buf[HTU31_SERIAL_NUMBER_CRC_OFFSET]) {
+ dev_err(&client->dev, "Serial number CRC mismatch\n");
+ return -EIO;
+ }
+
+ memcpy(data->serial_number, sn_buf, HTU31_SERIAL_NUMBER_LEN);
+
+ return 0;
+}
...
+static ssize_t heater_enable_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t count)
+{
+ struct htu31_data *data = dev_get_drvdata(dev);
+ u8 heater_cmd;
+ bool status;
+ int ret;
+
+ ret = kstrtobool(buf, &status);
+ if (ret)
+ return ret;
+
+ heater_cmd = status ? HTU31_HEATER_ON_CMD : HTU31_HEATER_OFF_CMD;
+
+ guard(mutex)(&data->i2c_lock);
+
+ ret = i2c_master_send(data->client, &heater_cmd, 1);
+ if (ret < 0)
+ return -EIO;
Why not return ret?
+
+ data->heater_enable = status;
+
+ return count;
+}
+
+static DEVICE_ATTR_RW(heater_enable);
+
+static ssize_t serial_number_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct htu31_data *data = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%X%X%X\n", data->serial_number[0],
+ data->serial_number[1],
+ data->serial_number[2]);
+}
+
+static DEVICE_ATTR_RO(serial_number);
+
+static struct attribute *htu31_attrs[] = {
+ &dev_attr_heater_enable.attr,
+ &dev_attr_serial_number.attr,
+ NULL,
No need for trailing comma after a terminator
+};
+
+ATTRIBUTE_GROUPS(htu31);
+
+static const struct hwmon_channel_info * const htu31_info[] = {
+ HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT),
+ HWMON_CHANNEL_INFO(humidity, HWMON_H_INPUT),
+ NULL,
No need for trailing comma after a terminator
+};
...
+static int htu31_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct device *hwmon_dev;
+ struct htu31_data *data;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->client = client;
+ data->wait_time = HTU31_TEMPERATURE_CONV_TIME + HTU31_HUMIDITY_CONV_TIME;
+
+ mutex_init(&data->i2c_lock);
Maybe devm_mutex_init()?
+
+ crc8_populate_msb(htu31_crc8_table, HTU31_CRC8_POLYNOMIAL);
+
+ if (serial_number_populate(data)) {
Maybe:
ret = serial_number_populate(data);
if (ret) {
...
return ret;
}
+ dev_err(dev, "Failed to read serial number\n");
+ return -EIO;
+ }
+
+ hwmon_dev = devm_hwmon_device_register_with_info(dev,
+ client->name,
+ data,
+ &htu31_chip_info,
+ htu31_groups);
+
+ return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static const struct i2c_device_id htu31_id[] = {
+ { "htu31" },
+ { },
No need for trailing comma after a terminator
+};
+MODULE_DEVICE_TABLE(i2c, htu31_id);
+
+#if IS_ENABLED(CONFIG_OF)
+static const struct of_device_id htu31_of_match[] = {
+ { .compatible = "meas,htu31" },
+ { },
No need for trailing comma after a terminator
+};
+MODULE_DEVICE_TABLE(of, htu31_of_match);
...
CJ
