Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
iio: chemical: Add driver for SEN0322
Add support for the DFRobot SEN0322 oxygen sensor.
To instantiate (assuming device is connected to I2C-2):
echo 'sen0322 0x73' > /sys/class/i2c-dev/i2c-2/device/new_device
To get the oxygen concentration (assuming device is iio:device0) multiply
the values read from:
/sys/bus/iio/devices/iio:device0/in_concentration_raw
/sys/bus/iio/devices/iio:device0/in_concentration_scale
Datasheet: https://wiki.dfrobot.com/Gravity_I2C_Oxygen_Sensor_SKU_SEN0322
Signed-off-by: Tóth János <gomba007@gmail.com>
Link: https://patch.msgid.link/20250506-iio-chemical-sen0322-v4-2-1465ac8dc190@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
authored by
Tóth János
and committed by
Jonathan Cameron
d524b3e0
844ca960
+178
+6
MAINTAINERS
+6
MAINTAINERS
···
6863
6863
S: Maintained
6864
6864
F: drivers/rtc/rtc-sd2405al.c
6865
6865
6866
+
DFROBOT SEN0322 DRIVER
6867
+
M: Tóth János <gomba007@gmail.com>
6868
+
L: linux-iio@vger.kernel.org
6869
+
S: Maintained
6870
+
F: drivers/iio/chemical/sen0322.c
6871
+
6866
6872
DH ELECTRONICS DHSOM SOM AND BOARD SUPPORT
6867
6873
M: Christoph Niedermaier <cniedermaier@dh-electronics.com>
6868
6874
M: Marek Vasut <marex@denx.de>
+10
drivers/iio/chemical/Kconfig
+10
drivers/iio/chemical/Kconfig
···
176
176
To compile this driver as a module, choose M here: the module will
177
177
be called scd4x.
178
178
179
+
config SEN0322
180
+
tristate "SEN0322 oxygen sensor"
181
+
depends on I2C
182
+
select REGMAP_I2C
183
+
help
184
+
Say Y here to build support for the DFRobot SEN0322 oxygen sensor.
185
+
186
+
To compile this driver as a module, choose M here: the module will
187
+
be called sen0322.
188
+
179
189
config SENSIRION_SGP30
180
190
tristate "Sensirion SGPxx gas sensors"
181
191
depends on I2C
+1
drivers/iio/chemical/Makefile
+1
drivers/iio/chemical/Makefile
···
21
21
obj-$(CONFIG_SCD30_I2C) += scd30_i2c.o
22
22
obj-$(CONFIG_SCD30_SERIAL) += scd30_serial.o
23
23
obj-$(CONFIG_SCD4X) += scd4x.o
24
+
obj-$(CONFIG_SEN0322) += sen0322.o
24
25
obj-$(CONFIG_SENSEAIR_SUNRISE_CO2) += sunrise_co2.o
25
26
obj-$(CONFIG_SENSIRION_SGP30) += sgp30.o
26
27
obj-$(CONFIG_SENSIRION_SGP40) += sgp40.o
+161
drivers/iio/chemical/sen0322.c
+161
drivers/iio/chemical/sen0322.c
···
1
+
// SPDX-License-Identifier: GPL-2.0
2
+
/*
3
+
* Driver for the DFRobot SEN0322 oxygen sensor.
4
+
*
5
+
* Datasheet:
6
+
* https://wiki.dfrobot.com/Gravity_I2C_Oxygen_Sensor_SKU_SEN0322
7
+
*
8
+
* Possible I2C slave addresses:
9
+
* 0x70
10
+
* 0x71
11
+
* 0x72
12
+
* 0x73
13
+
*
14
+
* Copyright (C) 2025 Tóth János <gomba007@gmail.com>
15
+
*/
16
+
17
+
#include <linux/i2c.h>
18
+
#include <linux/regmap.h>
19
+
20
+
#include <linux/iio/iio.h>
21
+
22
+
#define SEN0322_REG_DATA 0x03
23
+
#define SEN0322_REG_COEFF 0x0A
24
+
25
+
struct sen0322 {
26
+
struct regmap *regmap;
27
+
};
28
+
29
+
static int sen0322_read_data(struct sen0322 *sen0322)
30
+
{
31
+
u8 data[3] = { };
32
+
int ret;
33
+
34
+
ret = regmap_bulk_read(sen0322->regmap, SEN0322_REG_DATA, data,
35
+
sizeof(data));
36
+
if (ret < 0)
37
+
return ret;
38
+
39
+
/*
40
+
* The actual value in the registers is:
41
+
* val = data[0] + data[1] / 10 + data[2] / 100
42
+
* but it is multiplied by 100 here to avoid floating-point math
43
+
* and the scale is divided by 100 to compensate this.
44
+
*/
45
+
return data[0] * 100 + data[1] * 10 + data[2];
46
+
}
47
+
48
+
static int sen0322_read_scale(struct sen0322 *sen0322, int *num, int *den)
49
+
{
50
+
u32 val;
51
+
int ret;
52
+
53
+
ret = regmap_read(sen0322->regmap, SEN0322_REG_COEFF, &val);
54
+
if (ret < 0)
55
+
return ret;
56
+
57
+
if (val) {
58
+
*num = val;
59
+
*den = 100000; /* Coeff is scaled by 1000 at calibration. */
60
+
} else { /* The device is not calibrated, using the factory-defaults. */
61
+
*num = 209; /* Oxygen content in the atmosphere is 20.9%. */
62
+
*den = 120000; /* Output of the sensor at 20.9% is 120 uA. */
63
+
}
64
+
65
+
dev_dbg(regmap_get_device(sen0322->regmap), "scale: %d/%d\n",
66
+
*num, *den);
67
+
68
+
return 0;
69
+
}
70
+
71
+
static int sen0322_read_raw(struct iio_dev *iio_dev,
72
+
const struct iio_chan_spec *chan,
73
+
int *val, int *val2, long mask)
74
+
{
75
+
struct sen0322 *sen0322 = iio_priv(iio_dev);
76
+
int ret;
77
+
78
+
if (chan->type != IIO_CONCENTRATION)
79
+
return -EINVAL;
80
+
81
+
switch (mask) {
82
+
case IIO_CHAN_INFO_RAW:
83
+
ret = sen0322_read_data(sen0322);
84
+
if (ret < 0)
85
+
return ret;
86
+
87
+
*val = ret;
88
+
return IIO_VAL_INT;
89
+
90
+
case IIO_CHAN_INFO_SCALE:
91
+
ret = sen0322_read_scale(sen0322, val, val2);
92
+
if (ret < 0)
93
+
return ret;
94
+
95
+
return IIO_VAL_FRACTIONAL;
96
+
97
+
default:
98
+
return -EINVAL;
99
+
}
100
+
}
101
+
102
+
static const struct iio_info sen0322_info = {
103
+
.read_raw = sen0322_read_raw,
104
+
};
105
+
106
+
static const struct regmap_config sen0322_regmap_conf = {
107
+
.reg_bits = 8,
108
+
.val_bits = 8,
109
+
};
110
+
111
+
static const struct iio_chan_spec sen0322_channel = {
112
+
.type = IIO_CONCENTRATION,
113
+
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
114
+
BIT(IIO_CHAN_INFO_SCALE),
115
+
};
116
+
117
+
static int sen0322_probe(struct i2c_client *client)
118
+
{
119
+
struct sen0322 *sen0322;
120
+
struct iio_dev *iio_dev;
121
+
122
+
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
123
+
return -ENODEV;
124
+
125
+
iio_dev = devm_iio_device_alloc(&client->dev, sizeof(*sen0322));
126
+
if (!iio_dev)
127
+
return -ENOMEM;
128
+
129
+
sen0322 = iio_priv(iio_dev);
130
+
131
+
sen0322->regmap = devm_regmap_init_i2c(client, &sen0322_regmap_conf);
132
+
if (IS_ERR(sen0322->regmap))
133
+
return PTR_ERR(sen0322->regmap);
134
+
135
+
iio_dev->info = &sen0322_info;
136
+
iio_dev->name = "sen0322";
137
+
iio_dev->channels = &sen0322_channel;
138
+
iio_dev->num_channels = 1;
139
+
iio_dev->modes = INDIO_DIRECT_MODE;
140
+
141
+
return devm_iio_device_register(&client->dev, iio_dev);
142
+
}
143
+
144
+
static const struct of_device_id sen0322_of_match[] = {
145
+
{ .compatible = "dfrobot,sen0322" },
146
+
{ }
147
+
};
148
+
MODULE_DEVICE_TABLE(of, sen0322_of_match);
149
+
150
+
static struct i2c_driver sen0322_driver = {
151
+
.driver = {
152
+
.name = "sen0322",
153
+
.of_match_table = sen0322_of_match,
154
+
},
155
+
.probe = sen0322_probe,
156
+
};
157
+
module_i2c_driver(sen0322_driver);
158
+
159
+
MODULE_AUTHOR("Tóth János <gomba007@gmail.com>");
160
+
MODULE_LICENSE("GPL");
161
+
MODULE_DESCRIPTION("SEN0322 oxygen sensor driver");