143fbe66dSAndre Werner // SPDX-License-Identifier: GPL-2.0-or-later
243fbe66dSAndre Werner /*
343fbe66dSAndre Werner * This is a non-complete driver implementation for the
443fbe66dSAndre Werner * HS3001 humidity and temperature sensor and compatibles. It does not include
543fbe66dSAndre Werner * the configuration possibilities, where it needs to be set to 'programming mode'
643fbe66dSAndre Werner * during power-up.
743fbe66dSAndre Werner *
843fbe66dSAndre Werner *
943fbe66dSAndre Werner * Copyright (C) 2023 SYS TEC electronic AG
1043fbe66dSAndre Werner * Author: Andre Werner <andre.werner@systec-electronic.com>
1143fbe66dSAndre Werner */
1243fbe66dSAndre Werner
1343fbe66dSAndre Werner #include <linux/bitfield.h>
1443fbe66dSAndre Werner #include <linux/delay.h>
1543fbe66dSAndre Werner #include <linux/err.h>
1643fbe66dSAndre Werner #include <linux/hwmon.h>
1743fbe66dSAndre Werner #include <linux/i2c.h>
1843fbe66dSAndre Werner #include <linux/init.h>
1943fbe66dSAndre Werner #include <linux/kernel.h>
2043fbe66dSAndre Werner #include <linux/module.h>
2143fbe66dSAndre Werner #include <linux/of_device.h>
2243fbe66dSAndre Werner #include <linux/slab.h>
2343fbe66dSAndre Werner #include <linux/types.h>
2443fbe66dSAndre Werner
2543fbe66dSAndre Werner /* Measurement times */
2643fbe66dSAndre Werner #define HS3001_WAKEUP_TIME 100 /* us */
2743fbe66dSAndre Werner #define HS3001_8BIT_RESOLUTION 550 /* us */
2843fbe66dSAndre Werner #define HS3001_10BIT_RESOLUTION 1310 /* us */
2943fbe66dSAndre Werner #define HS3001_12BIT_RESOLUTION 4500 /* us */
3043fbe66dSAndre Werner #define HS3001_14BIT_RESOLUTION 16900 /* us */
3143fbe66dSAndre Werner
3243fbe66dSAndre Werner #define HS3001_RESPONSE_LENGTH 4
3343fbe66dSAndre Werner
3443fbe66dSAndre Werner #define HS3001_FIXPOINT_ARITH 1000U
3543fbe66dSAndre Werner
3643fbe66dSAndre Werner #define HS3001_MASK_HUMIDITY_0X3FFF GENMASK(13, 0)
3743fbe66dSAndre Werner #define HS3001_MASK_STATUS_0XC0 GENMASK(7, 6)
3843fbe66dSAndre Werner
3943fbe66dSAndre Werner /* Definitions for Status Bits of A/D Data */
4043fbe66dSAndre Werner #define HS3001_DATA_VALID 0x00 /* Valid Data */
4143fbe66dSAndre Werner #define HS3001_DATA_STALE 0x01 /* Stale Data */
4243fbe66dSAndre Werner
4343fbe66dSAndre Werner struct hs3001_data {
4443fbe66dSAndre Werner struct i2c_client *client;
4543fbe66dSAndre Werner struct mutex i2c_lock; /* lock for sending i2c commands */
4643fbe66dSAndre Werner u32 wait_time; /* in us */
4743fbe66dSAndre Werner int temperature; /* in milli degree */
4843fbe66dSAndre Werner u32 humidity; /* in milli % */
4943fbe66dSAndre Werner };
5043fbe66dSAndre Werner
hs3001_extract_temperature(u16 raw)5143fbe66dSAndre Werner static int hs3001_extract_temperature(u16 raw)
5243fbe66dSAndre Werner {
5343fbe66dSAndre Werner /* fixpoint arithmetic 1 digit */
5443fbe66dSAndre Werner u32 temp = (raw >> 2) * HS3001_FIXPOINT_ARITH * 165;
5543fbe66dSAndre Werner
5643fbe66dSAndre Werner temp /= (1 << 14) - 1;
5743fbe66dSAndre Werner
5843fbe66dSAndre Werner return (int)temp - 40 * HS3001_FIXPOINT_ARITH;
5943fbe66dSAndre Werner }
6043fbe66dSAndre Werner
hs3001_extract_humidity(u16 raw)6143fbe66dSAndre Werner static u32 hs3001_extract_humidity(u16 raw)
6243fbe66dSAndre Werner {
6343fbe66dSAndre Werner u32 hum = (raw & HS3001_MASK_HUMIDITY_0X3FFF) * HS3001_FIXPOINT_ARITH * 100;
6443fbe66dSAndre Werner
65748465a5SColin Ian King return hum / (1 << 14) - 1;
6643fbe66dSAndre Werner }
6743fbe66dSAndre Werner
hs3001_data_fetch_command(struct i2c_client * client,struct hs3001_data * data)6843fbe66dSAndre Werner static int hs3001_data_fetch_command(struct i2c_client *client,
6943fbe66dSAndre Werner struct hs3001_data *data)
7043fbe66dSAndre Werner {
7143fbe66dSAndre Werner int ret;
7243fbe66dSAndre Werner u8 buf[HS3001_RESPONSE_LENGTH];
7343fbe66dSAndre Werner u8 hs3001_status;
7443fbe66dSAndre Werner
7543fbe66dSAndre Werner ret = i2c_master_recv(client, buf, HS3001_RESPONSE_LENGTH);
7643fbe66dSAndre Werner if (ret != HS3001_RESPONSE_LENGTH) {
7743fbe66dSAndre Werner ret = ret < 0 ? ret : -EIO;
7843fbe66dSAndre Werner dev_dbg(&client->dev,
7943fbe66dSAndre Werner "Error in i2c communication. Error code: %d.\n", ret);
8043fbe66dSAndre Werner return ret;
8143fbe66dSAndre Werner }
8243fbe66dSAndre Werner
8343fbe66dSAndre Werner hs3001_status = FIELD_GET(HS3001_MASK_STATUS_0XC0, buf[0]);
8443fbe66dSAndre Werner if (hs3001_status == HS3001_DATA_STALE) {
8543fbe66dSAndre Werner dev_dbg(&client->dev, "Sensor busy.\n");
8643fbe66dSAndre Werner return -EBUSY;
8743fbe66dSAndre Werner }
8843fbe66dSAndre Werner if (hs3001_status != HS3001_DATA_VALID) {
8943fbe66dSAndre Werner dev_dbg(&client->dev, "Data invalid.\n");
9043fbe66dSAndre Werner return -EIO;
9143fbe66dSAndre Werner }
9243fbe66dSAndre Werner
9343fbe66dSAndre Werner data->humidity =
9443fbe66dSAndre Werner hs3001_extract_humidity(be16_to_cpup((__be16 *)&buf[0]));
9543fbe66dSAndre Werner data->temperature =
9643fbe66dSAndre Werner hs3001_extract_temperature(be16_to_cpup((__be16 *)&buf[2]));
9743fbe66dSAndre Werner
9843fbe66dSAndre Werner return 0;
9943fbe66dSAndre Werner }
10043fbe66dSAndre Werner
hs3001_is_visible(const void * data,enum hwmon_sensor_types type,u32 attr,int channel)10143fbe66dSAndre Werner static umode_t hs3001_is_visible(const void *data, enum hwmon_sensor_types type,
10243fbe66dSAndre Werner u32 attr, int channel)
10343fbe66dSAndre Werner {
10443fbe66dSAndre Werner /* Both, humidity and temperature can only be read. */
10543fbe66dSAndre Werner return 0444;
10643fbe66dSAndre Werner }
10743fbe66dSAndre Werner
hs3001_read(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long * val)10843fbe66dSAndre Werner static int hs3001_read(struct device *dev, enum hwmon_sensor_types type,
10943fbe66dSAndre Werner u32 attr, int channel, long *val)
11043fbe66dSAndre Werner {
11143fbe66dSAndre Werner struct hs3001_data *data = dev_get_drvdata(dev);
11243fbe66dSAndre Werner struct i2c_client *client = data->client;
11343fbe66dSAndre Werner int ret;
11443fbe66dSAndre Werner
11543fbe66dSAndre Werner mutex_lock(&data->i2c_lock);
11643fbe66dSAndre Werner ret = i2c_master_send(client, NULL, 0);
11743fbe66dSAndre Werner if (ret < 0) {
11843fbe66dSAndre Werner mutex_unlock(&data->i2c_lock);
11943fbe66dSAndre Werner return ret;
12043fbe66dSAndre Werner }
12143fbe66dSAndre Werner
12243fbe66dSAndre Werner /*
12343fbe66dSAndre Werner * Sensor needs some time to process measurement depending on
12443fbe66dSAndre Werner * resolution (ref. datasheet)
12543fbe66dSAndre Werner */
12643fbe66dSAndre Werner fsleep(data->wait_time);
12743fbe66dSAndre Werner
12843fbe66dSAndre Werner ret = hs3001_data_fetch_command(client, data);
12943fbe66dSAndre Werner mutex_unlock(&data->i2c_lock);
13043fbe66dSAndre Werner
13143fbe66dSAndre Werner if (ret < 0)
13243fbe66dSAndre Werner return ret;
13343fbe66dSAndre Werner
13443fbe66dSAndre Werner switch (type) {
13543fbe66dSAndre Werner case hwmon_temp:
13643fbe66dSAndre Werner switch (attr) {
13743fbe66dSAndre Werner case hwmon_temp_input:
13843fbe66dSAndre Werner *val = data->temperature;
13943fbe66dSAndre Werner break;
14043fbe66dSAndre Werner default:
14143fbe66dSAndre Werner return -EINVAL;
14243fbe66dSAndre Werner }
14343fbe66dSAndre Werner break;
14443fbe66dSAndre Werner case hwmon_humidity:
14543fbe66dSAndre Werner switch (attr) {
14643fbe66dSAndre Werner case hwmon_humidity_input:
14743fbe66dSAndre Werner *val = data->humidity;
14843fbe66dSAndre Werner break;
14943fbe66dSAndre Werner default:
15043fbe66dSAndre Werner return -EINVAL;
15143fbe66dSAndre Werner }
15243fbe66dSAndre Werner break;
15343fbe66dSAndre Werner default:
15443fbe66dSAndre Werner return -EINVAL;
15543fbe66dSAndre Werner }
15643fbe66dSAndre Werner
15743fbe66dSAndre Werner return 0;
15843fbe66dSAndre Werner }
15943fbe66dSAndre Werner
16043fbe66dSAndre Werner static const struct hwmon_channel_info *hs3001_info[] = {
16143fbe66dSAndre Werner HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT),
16243fbe66dSAndre Werner HWMON_CHANNEL_INFO(humidity, HWMON_H_INPUT),
16343fbe66dSAndre Werner NULL
16443fbe66dSAndre Werner };
16543fbe66dSAndre Werner
16643fbe66dSAndre Werner static const struct hwmon_ops hs3001_hwmon_ops = {
16743fbe66dSAndre Werner .is_visible = hs3001_is_visible,
16843fbe66dSAndre Werner .read = hs3001_read,
16943fbe66dSAndre Werner };
17043fbe66dSAndre Werner
17143fbe66dSAndre Werner static const struct hwmon_chip_info hs3001_chip_info = {
17243fbe66dSAndre Werner .ops = &hs3001_hwmon_ops,
17343fbe66dSAndre Werner .info = hs3001_info,
17443fbe66dSAndre Werner };
17543fbe66dSAndre Werner
17643fbe66dSAndre Werner /* device ID table */
17743fbe66dSAndre Werner static const struct i2c_device_id hs3001_ids[] = {
178*d8a66f36SUwe Kleine-König { "hs3001" },
17943fbe66dSAndre Werner { },
18043fbe66dSAndre Werner };
18143fbe66dSAndre Werner
18243fbe66dSAndre Werner MODULE_DEVICE_TABLE(i2c, hs3001_ids);
18343fbe66dSAndre Werner
18443fbe66dSAndre Werner static const struct of_device_id hs3001_of_match[] = {
18543fbe66dSAndre Werner {.compatible = "renesas,hs3001"},
18643fbe66dSAndre Werner { },
18743fbe66dSAndre Werner };
18843fbe66dSAndre Werner
18943fbe66dSAndre Werner MODULE_DEVICE_TABLE(of, hs3001_of_match);
19043fbe66dSAndre Werner
hs3001_probe(struct i2c_client * client)19143fbe66dSAndre Werner static int hs3001_probe(struct i2c_client *client)
19243fbe66dSAndre Werner {
19343fbe66dSAndre Werner struct hs3001_data *data;
19443fbe66dSAndre Werner struct device *hwmon_dev;
19543fbe66dSAndre Werner struct device *dev = &client->dev;
19643fbe66dSAndre Werner
19743fbe66dSAndre Werner if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
19843fbe66dSAndre Werner return -EOPNOTSUPP;
19943fbe66dSAndre Werner
20043fbe66dSAndre Werner data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
20143fbe66dSAndre Werner if (!data)
20243fbe66dSAndre Werner return -ENOMEM;
20343fbe66dSAndre Werner
20443fbe66dSAndre Werner data->client = client;
20543fbe66dSAndre Werner
20643fbe66dSAndre Werner /*
20743fbe66dSAndre Werner * Measurement time = wake-up time + measurement time temperature
20843fbe66dSAndre Werner * + measurement time humidity. This is currently static, because
20943fbe66dSAndre Werner * enabling programming mode is not supported, yet.
21043fbe66dSAndre Werner */
21143fbe66dSAndre Werner data->wait_time = (HS3001_WAKEUP_TIME + HS3001_14BIT_RESOLUTION +
21243fbe66dSAndre Werner HS3001_14BIT_RESOLUTION);
21343fbe66dSAndre Werner
21443fbe66dSAndre Werner mutex_init(&data->i2c_lock);
21543fbe66dSAndre Werner
21643fbe66dSAndre Werner hwmon_dev = devm_hwmon_device_register_with_info(dev,
21743fbe66dSAndre Werner client->name,
21843fbe66dSAndre Werner data,
21943fbe66dSAndre Werner &hs3001_chip_info,
22043fbe66dSAndre Werner NULL);
22143fbe66dSAndre Werner
22243fbe66dSAndre Werner if (IS_ERR(hwmon_dev))
22343fbe66dSAndre Werner return dev_err_probe(dev, PTR_ERR(hwmon_dev),
22443fbe66dSAndre Werner "Unable to register hwmon device.\n");
22543fbe66dSAndre Werner
22643fbe66dSAndre Werner return 0;
22743fbe66dSAndre Werner }
22843fbe66dSAndre Werner
22943fbe66dSAndre Werner static struct i2c_driver hs3001_i2c_driver = {
23043fbe66dSAndre Werner .driver = {
23143fbe66dSAndre Werner .name = "hs3001",
23243fbe66dSAndre Werner .of_match_table = hs3001_of_match,
23343fbe66dSAndre Werner },
23443fbe66dSAndre Werner .probe = hs3001_probe,
23543fbe66dSAndre Werner .id_table = hs3001_ids,
23643fbe66dSAndre Werner };
23743fbe66dSAndre Werner
23843fbe66dSAndre Werner module_i2c_driver(hs3001_i2c_driver);
23943fbe66dSAndre Werner
24043fbe66dSAndre Werner MODULE_AUTHOR("Andre Werner <andre.werner@systec-electronic.com>");
24143fbe66dSAndre Werner MODULE_DESCRIPTION("HS3001 humidity and temperature sensor base driver");
24243fbe66dSAndre Werner MODULE_LICENSE("GPL");
243