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11#include <linux/iio/iio.h>
12#include <linux/iio/sysfs.h>
13#include <linux/device.h>
14#include <linux/mutex.h>
15#include <linux/module.h>
16#include <linux/mod_devicetable.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};
115
116static bool tsys01_crc_valid(u16 *n_prom)
117{
118 u8 cnt;
119 u8 sum = 0;
120
121 for (cnt = 0; cnt < TSYS01_PROM_WORDS_NB; cnt++)
122 sum += ((n_prom[0] >> 8) + (n_prom[0] & 0xFF));
123
124 return (sum == 0);
125}
126
127static int tsys01_read_prom(struct iio_dev *indio_dev)
128{
129 int i, ret;
130 struct tsys01_dev *dev_data = iio_priv(indio_dev);
131 char buf[7 * TSYS01_PROM_WORDS_NB + 1];
132 char *ptr = buf;
133
134 for (i = 0; i < TSYS01_PROM_WORDS_NB; i++) {
135 ret = dev_data->read_prom_word(dev_data->client,
136 TSYS01_PROM_READ + (i << 1),
137 &dev_data->prom[i]);
138 if (ret)
139 return ret;
140
141 ret = sprintf(ptr, "0x%04x ", dev_data->prom[i]);
142 ptr += ret;
143 }
144
145 if (!tsys01_crc_valid(dev_data->prom)) {
146 dev_err(&indio_dev->dev, "prom crc check error\n");
147 return -ENODEV;
148 }
149 *ptr = 0;
150 dev_info(&indio_dev->dev, "PROM coefficients : %s\n", buf);
151
152 return 0;
153}
154
155static int tsys01_probe(struct iio_dev *indio_dev, struct device *dev)
156{
157 int ret;
158 struct tsys01_dev *dev_data = iio_priv(indio_dev);
159
160 mutex_init(&dev_data->lock);
161
162 indio_dev->info = &tsys01_info;
163 indio_dev->name = dev->driver->name;
164 indio_dev->modes = INDIO_DIRECT_MODE;
165 indio_dev->channels = tsys01_channels;
166 indio_dev->num_channels = ARRAY_SIZE(tsys01_channels);
167
168 ret = dev_data->reset(dev_data->client, TSYS01_RESET, 3000);
169 if (ret)
170 return ret;
171
172 ret = tsys01_read_prom(indio_dev);
173 if (ret)
174 return ret;
175
176 return devm_iio_device_register(dev, indio_dev);
177}
178
179static int tsys01_i2c_probe(struct i2c_client *client,
180 const struct i2c_device_id *id)
181{
182 struct tsys01_dev *dev_data;
183 struct iio_dev *indio_dev;
184
185 if (!i2c_check_functionality(client->adapter,
186 I2C_FUNC_SMBUS_WORD_DATA |
187 I2C_FUNC_SMBUS_WRITE_BYTE |
188 I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
189 dev_err(&client->dev,
190 "Adapter does not support some i2c transaction\n");
191 return -EOPNOTSUPP;
192 }
193
194 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*dev_data));
195 if (!indio_dev)
196 return -ENOMEM;
197
198 dev_data = iio_priv(indio_dev);
199 dev_data->client = client;
200 dev_data->reset = ms_sensors_reset;
201 dev_data->read_prom_word = ms_sensors_read_prom_word;
202 dev_data->convert_and_read = ms_sensors_convert_and_read;
203
204 i2c_set_clientdata(client, indio_dev);
205
206 return tsys01_probe(indio_dev, &client->dev);
207}
208
209static const struct i2c_device_id tsys01_id[] = {
210 {"tsys01", 0},
211 {}
212};
213MODULE_DEVICE_TABLE(i2c, tsys01_id);
214
215static const struct of_device_id tsys01_of_match[] = {
216 { .compatible = "meas,tsys01", },
217 { },
218};
219MODULE_DEVICE_TABLE(of, tsys01_of_match);
220
221static struct i2c_driver tsys01_driver = {
222 .probe = tsys01_i2c_probe,
223 .id_table = tsys01_id,
224 .driver = {
225 .name = "tsys01",
226 .of_match_table = tsys01_of_match,
227 },
228};
229
230module_i2c_driver(tsys01_driver);
231
232MODULE_DESCRIPTION("Measurement-Specialties tsys01 temperature driver");
233MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>");
234MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>");
235MODULE_LICENSE("GPL v2");
236
