1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * tsys02d.c - Support for Measurement-Specialties tsys02d temperature sensor
4 *
5 * Copyright (c) 2015 Measurement-Specialties
6 *
7 * (7-bit I2C slave address 0x40)
8 *
9 * Datasheet:
10 * http://www.meas-spec.com/downloads/Digital_Sensor_TSYS02D.pdf
11 */
12
13#include <linux/init.h>
14#include <linux/device.h>
15#include <linux/kernel.h>
16#include <linux/stat.h>
17#include <linux/module.h>
18#include <linux/iio/iio.h>
19#include <linux/iio/sysfs.h>
20
21#include "../common/ms_sensors/ms_sensors_i2c.h"
22
23#define TSYS02D_RESET 0xFE
24
25static const int tsys02d_samp_freq[4] = { 20, 40, 70, 140 };
26/* String copy of the above const for readability purpose */
27static const char tsys02d_show_samp_freq[] = "20 40 70 140";
28
29static int tsys02d_read_raw(struct iio_dev *indio_dev,
30 struct iio_chan_spec const *channel, int *val,
31 int *val2, long mask)
32{
33 int ret;
34 s32 temperature;
35 struct ms_ht_dev *dev_data = iio_priv(indio_dev);
36
37 switch (mask) {
38 case IIO_CHAN_INFO_PROCESSED:
39 switch (channel->type) {
40 case IIO_TEMP: /* in milli °C */
41 ret = ms_sensors_ht_read_temperature(dev_data,
42 temperature: &temperature);
43 if (ret)
44 return ret;
45 *val = temperature;
46
47 return IIO_VAL_INT;
48 default:
49 return -EINVAL;
50 }
51 case IIO_CHAN_INFO_SAMP_FREQ:
52 *val = tsys02d_samp_freq[dev_data->res_index];
53
54 return IIO_VAL_INT;
55 default:
56 return -EINVAL;
57 }
58}
59
60static int tsys02d_write_raw(struct iio_dev *indio_dev,
61 struct iio_chan_spec const *chan,
62 int val, int val2, long mask)
63{
64 struct ms_ht_dev *dev_data = iio_priv(indio_dev);
65 int i, ret;
66
67 switch (mask) {
68 case IIO_CHAN_INFO_SAMP_FREQ:
69 i = ARRAY_SIZE(tsys02d_samp_freq);
70 while (i-- > 0)
71 if (val == tsys02d_samp_freq[i])
72 break;
73 if (i < 0)
74 return -EINVAL;
75 mutex_lock(&dev_data->lock);
76 dev_data->res_index = i;
77 ret = ms_sensors_write_resolution(dev_data, i);
78 mutex_unlock(lock: &dev_data->lock);
79
80 return ret;
81 default:
82 return -EINVAL;
83 }
84}
85
86static const struct iio_chan_spec tsys02d_channels[] = {
87 {
88 .type = IIO_TEMP,
89 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_PROCESSED),
90 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
91 }
92};
93
94static ssize_t tsys02_read_battery_low(struct device *dev,
95 struct device_attribute *attr,
96 char *buf)
97{
98 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
99 struct ms_ht_dev *dev_data = iio_priv(indio_dev);
100
101 return ms_sensors_show_battery_low(dev_data, buf);
102}
103
104static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(tsys02d_show_samp_freq);
105static IIO_DEVICE_ATTR(battery_low, S_IRUGO,
106 tsys02_read_battery_low, NULL, 0);
107
108static struct attribute *tsys02d_attributes[] = {
109 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
110 &iio_dev_attr_battery_low.dev_attr.attr,
111 NULL,
112};
113
114static const struct attribute_group tsys02d_attribute_group = {
115 .attrs = tsys02d_attributes,
116};
117
118static const struct iio_info tsys02d_info = {
119 .read_raw = tsys02d_read_raw,
120 .write_raw = tsys02d_write_raw,
121 .attrs = &tsys02d_attribute_group,
122};
123
124static int tsys02d_probe(struct i2c_client *client)
125{
126 const struct i2c_device_id *id = i2c_client_get_device_id(client);
127 struct ms_ht_dev *dev_data;
128 struct iio_dev *indio_dev;
129 int ret;
130 u64 serial_number;
131
132 if (!i2c_check_functionality(adap: client->adapter,
133 I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
134 I2C_FUNC_SMBUS_WRITE_BYTE |
135 I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
136 dev_err(&client->dev,
137 "Adapter does not support some i2c transaction\n");
138 return -EOPNOTSUPP;
139 }
140
141 indio_dev = devm_iio_device_alloc(parent: &client->dev, sizeof_priv: sizeof(*dev_data));
142 if (!indio_dev)
143 return -ENOMEM;
144
145 dev_data = iio_priv(indio_dev);
146 dev_data->client = client;
147 dev_data->res_index = 0;
148 mutex_init(&dev_data->lock);
149
150 indio_dev->info = &tsys02d_info;
151 indio_dev->name = id->name;
152 indio_dev->modes = INDIO_DIRECT_MODE;
153 indio_dev->channels = tsys02d_channels;
154 indio_dev->num_channels = ARRAY_SIZE(tsys02d_channels);
155
156 i2c_set_clientdata(client, data: indio_dev);
157
158 ret = ms_sensors_reset(cli: client, TSYS02D_RESET, delay: 15000);
159 if (ret)
160 return ret;
161
162 ret = ms_sensors_read_serial(client, sn: &serial_number);
163 if (ret)
164 return ret;
165 dev_info(&client->dev, "Serial number : %llx", serial_number);
166
167 return devm_iio_device_register(&client->dev, indio_dev);
168}
169
170static const struct i2c_device_id tsys02d_id[] = {
171 {"tsys02d", 0},
172 {}
173};
174MODULE_DEVICE_TABLE(i2c, tsys02d_id);
175
176static struct i2c_driver tsys02d_driver = {
177 .probe = tsys02d_probe,
178 .id_table = tsys02d_id,
179 .driver = {
180 .name = "tsys02d",
181 },
182};
183
184module_i2c_driver(tsys02d_driver);
185
186MODULE_DESCRIPTION("Measurement-Specialties tsys02d temperature driver");
187MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>");
188MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>");
189MODULE_LICENSE("GPL v2");
190MODULE_IMPORT_NS(IIO_MEAS_SPEC_SENSORS);
191

source code of linux/drivers/iio/temperature/tsys02d.c