1
2
3
4
5
6
7
8
9
10
11
12#include <linux/iio/iio.h>
13#include <linux/iio/sysfs.h>
14#include <linux/device.h>
15#include <linux/mutex.h>
16#include <linux/module.h>
17#include <linux/init.h>
18#include <linux/kernel.h>
19#include <linux/stat.h>
20#include "../common/ms_sensors/ms_sensors_i2c.h"
21
22
23#define TSYS01_RESET 0x1E
24#define TSYS01_CONVERSION_START 0x48
25#define TSYS01_ADC_READ 0x00
26#define TSYS01_PROM_READ 0xA0
27
28#define TSYS01_PROM_WORDS_NB 8
29
30struct tsys01_dev {
31 void *client;
32 struct mutex lock;
33
34 int (*reset)(void *cli, u8 cmd, unsigned int delay);
35 int (*convert_and_read)(void *cli, u8 conv, u8 rd,
36 unsigned int delay, u32 *adc);
37 int (*read_prom_word)(void *cli, int cmd, u16 *word);
38
39 u16 prom[TSYS01_PROM_WORDS_NB];
40};
41
42
43static const int coeff_mul[] = { -1500000, 1000000, -2000000,
44 4000000, -2000000 };
45
46static int tsys01_read_temperature(struct iio_dev *indio_dev,
47 s32 *temperature)
48{
49 int ret, i;
50 u32 adc;
51 s64 temp = 0;
52 struct tsys01_dev *dev_data = iio_priv(indio_dev);
53
54 mutex_lock(&dev_data->lock);
55 ret = dev_data->convert_and_read(dev_data->client,
56 TSYS01_CONVERSION_START,
57 TSYS01_ADC_READ, 9000, &adc);
58 mutex_unlock(&dev_data->lock);
59 if (ret)
60 return ret;
61
62 adc >>= 8;
63
64
65 for (i = 4; i > 0; i--) {
66 temp += coeff_mul[i] *
67 (s64)dev_data->prom[5 - i];
68 temp *= (s64)adc;
69 temp = div64_s64(temp, 100000);
70 }
71 temp *= 10;
72 temp += coeff_mul[0] * (s64)dev_data->prom[5];
73 temp = div64_s64(temp, 100000);
74
75 *temperature = temp;
76
77 return 0;
78}
79
80static int tsys01_read_raw(struct iio_dev *indio_dev,
81 struct iio_chan_spec const *channel, int *val,
82 int *val2, long mask)
83{
84 int ret;
85 s32 temperature;
86
87 switch (mask) {
88 case IIO_CHAN_INFO_PROCESSED:
89 switch (channel->type) {
90 case IIO_TEMP:
91 ret = tsys01_read_temperature(indio_dev, &temperature);
92 if (ret)
93 return ret;
94 *val = temperature;
95
96 return IIO_VAL_INT;
97 default:
98 return -EINVAL;
99 }
100 default:
101 return -EINVAL;
102 }
103}
104
105static const struct iio_chan_spec tsys01_channels[] = {
106 {
107 .type = IIO_TEMP,
108 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_PROCESSED),
109 }
110};
111
112static const struct iio_info tsys01_info = {
113 .read_raw = tsys01_read_raw,
114 .driver_module = THIS_MODULE,
115};
116
117static bool tsys01_crc_valid(u16 *n_prom)
118{
119 u8 cnt;
120 u8 sum = 0;
121
122 for (cnt = 0; cnt < TSYS01_PROM_WORDS_NB; cnt++)
123 sum += ((n_prom[0] >> 8) + (n_prom[0] & 0xFF));
124
125 return (sum == 0);
126}
127
128static int tsys01_read_prom(struct iio_dev *indio_dev)
129{
130 int i, ret;
131 struct tsys01_dev *dev_data = iio_priv(indio_dev);
132 char buf[7 * TSYS01_PROM_WORDS_NB + 1];
133 char *ptr = buf;
134
135 for (i = 0; i < TSYS01_PROM_WORDS_NB; i++) {
136 ret = dev_data->read_prom_word(dev_data->client,
137 TSYS01_PROM_READ + (i << 1),
138 &dev_data->prom[i]);
139 if (ret)
140 return ret;
141
142 ret = sprintf(ptr, "0x%04x ", dev_data->prom[i]);
143 ptr += ret;
144 }
145
146 if (!tsys01_crc_valid(dev_data->prom)) {
147 dev_err(&indio_dev->dev, "prom crc check error\n");
148 return -ENODEV;
149 }
150 *ptr = 0;
151 dev_info(&indio_dev->dev, "PROM coefficients : %s\n", buf);
152
153 return 0;
154}
155
156static int tsys01_probe(struct iio_dev *indio_dev, struct device *dev)
157{
158 int ret;
159 struct tsys01_dev *dev_data = iio_priv(indio_dev);
160
161 mutex_init(&dev_data->lock);
162
163 indio_dev->info = &tsys01_info;
164 indio_dev->name = dev->driver->name;
165 indio_dev->dev.parent = dev;
166 indio_dev->modes = INDIO_DIRECT_MODE;
167 indio_dev->channels = tsys01_channels;
168 indio_dev->num_channels = ARRAY_SIZE(tsys01_channels);
169
170 ret = dev_data->reset(dev_data->client, TSYS01_RESET, 3000);
171 if (ret)
172 return ret;
173
174 ret = tsys01_read_prom(indio_dev);
175 if (ret)
176 return ret;
177
178 return devm_iio_device_register(dev, indio_dev);
179}
180
181static int tsys01_i2c_probe(struct i2c_client *client,
182 const struct i2c_device_id *id)
183{
184 struct tsys01_dev *dev_data;
185 struct iio_dev *indio_dev;
186
187 if (!i2c_check_functionality(client->adapter,
188 I2C_FUNC_SMBUS_WORD_DATA |
189 I2C_FUNC_SMBUS_WRITE_BYTE |
190 I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
191 dev_err(&client->dev,
192 "Adapter does not support some i2c transaction\n");
193 return -EOPNOTSUPP;
194 }
195
196 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*dev_data));
197 if (!indio_dev)
198 return -ENOMEM;
199
200 dev_data = iio_priv(indio_dev);
201 dev_data->client = client;
202 dev_data->reset = ms_sensors_reset;
203 dev_data->read_prom_word = ms_sensors_read_prom_word;
204 dev_data->convert_and_read = ms_sensors_convert_and_read;
205
206 i2c_set_clientdata(client, indio_dev);
207
208 return tsys01_probe(indio_dev, &client->dev);
209}
210
211static const struct i2c_device_id tsys01_id[] = {
212 {"tsys01", 0},
213 {}
214};
215MODULE_DEVICE_TABLE(i2c, tsys01_id);
216
217static struct i2c_driver tsys01_driver = {
218 .probe = tsys01_i2c_probe,
219 .id_table = tsys01_id,
220 .driver = {
221 .name = "tsys01",
222 },
223};
224
225module_i2c_driver(tsys01_driver);
226
227MODULE_DESCRIPTION("Measurement-Specialties tsys01 temperature driver");
228MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>");
229MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>");
230MODULE_LICENSE("GPL v2");
231
