tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * tmp007.c - Support for TI TMP007 IR thermopile sensor with integrated math engine
3 *
4 * Copyright (c) 2017 Manivannan Sadhasivam <manivannanece23@gmail.com>
5 *
6 * This file is subject to the terms and conditions of version 2 of
7 * the GNU General Public License. See the file COPYING in the main
8 * directory of this archive for more details.
9 *
10 * Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
11 *
12 * (7-bit I2C slave address (0x40 - 0x47), changeable via ADR pins)
13 *
14 * Note: This driver assumes that the sensor has been calibrated beforehand
15 *
16 * TODO: ALERT irq, limit threshold events
17 *
18 */
19
20#include <linux/err.h>
21#include <linux/i2c.h>
22#include <linux/delay.h>
23#include <linux/module.h>
24#include <linux/pm.h>
25#include <linux/bitops.h>
26#include <linux/of.h>
27
28#include <linux/iio/iio.h>
29#include <linux/iio/sysfs.h>
30
31#define TMP007_TDIE 0x01
32#define TMP007_CONFIG 0x02
33#define TMP007_TOBJECT 0x03
34#define TMP007_STATUS 0x04
35#define TMP007_STATUS_MASK 0x05
36#define TMP007_MANUFACTURER_ID 0x1e
37#define TMP007_DEVICE_ID 0x1f
38
39#define TMP007_CONFIG_CONV_EN BIT(12)
40#define TMP007_CONFIG_COMP_EN BIT(5)
41#define TMP007_CONFIG_TC_EN BIT(6)
42#define TMP007_CONFIG_CR_MASK GENMASK(11, 9)
43#define TMP007_CONFIG_CR_SHIFT 9
44
45#define TMP007_STATUS_CONV_READY BIT(14)
46#define TMP007_STATUS_DATA_VALID BIT(9)
47
48#define TMP007_MANUFACTURER_MAGIC 0x5449
49#define TMP007_DEVICE_MAGIC 0x0078
50
51#define TMP007_TEMP_SHIFT 2
52
53struct tmp007_data {
54 struct i2c_client *client;
55 u16 config;
56};
57
58static const int tmp007_avgs[5][2] = { {4, 0}, {2, 0}, {1, 0},
59 {0, 500000}, {0, 250000} };
60
61static int tmp007_read_temperature(struct tmp007_data *data, u8 reg)
62{
63 s32 ret;
64 int tries = 50;
65
66 while (tries-- > 0) {
67 ret = i2c_smbus_read_word_swapped(data->client,
68 TMP007_STATUS);
69 if (ret < 0)
70 return ret;
71 if ((ret & TMP007_STATUS_CONV_READY) &&
72 !(ret & TMP007_STATUS_DATA_VALID))
73 break;
74 msleep(100);
75 }
76
77 if (tries < 0)
78 return -EIO;
79
80 return i2c_smbus_read_word_swapped(data->client, reg);
81}
82
83static int tmp007_powerdown(struct tmp007_data *data)
84{
85 return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
86 data->config & ~TMP007_CONFIG_CONV_EN);
87}
88
89static int tmp007_read_raw(struct iio_dev *indio_dev,
90 struct iio_chan_spec const *channel, int *val,
91 int *val2, long mask)
92{
93 struct tmp007_data *data = iio_priv(indio_dev);
94 s32 ret;
95 int conv_rate;
96
97 switch (mask) {
98 case IIO_CHAN_INFO_RAW:
99 switch (channel->channel2) {
100 case IIO_MOD_TEMP_AMBIENT: /* LSB: 0.03125 degree Celsius */
101 ret = i2c_smbus_read_word_swapped(data->client, TMP007_TDIE);
102 if (ret < 0)
103 return ret;
104 break;
105 case IIO_MOD_TEMP_OBJECT:
106 ret = tmp007_read_temperature(data, TMP007_TOBJECT);
107 if (ret < 0)
108 return ret;
109 break;
110 default:
111 return -EINVAL;
112 }
113
114 *val = sign_extend32(ret, 15) >> TMP007_TEMP_SHIFT;
115
116 return IIO_VAL_INT;
117 case IIO_CHAN_INFO_SCALE:
118 *val = 31;
119 *val2 = 250000;
120
121 return IIO_VAL_INT_PLUS_MICRO;
122 case IIO_CHAN_INFO_SAMP_FREQ:
123 conv_rate = (data->config & TMP007_CONFIG_CR_MASK)
124 >> TMP007_CONFIG_CR_SHIFT;
125 *val = tmp007_avgs[conv_rate][0];
126 *val2 = tmp007_avgs[conv_rate][1];
127
128 return IIO_VAL_INT_PLUS_MICRO;
129 default:
130 return -EINVAL;
131 }
132}
133
134static int tmp007_write_raw(struct iio_dev *indio_dev,
135 struct iio_chan_spec const *channel, int val,
136 int val2, long mask)
137{
138 struct tmp007_data *data = iio_priv(indio_dev);
139 int i;
140 u16 tmp;
141
142 if (mask == IIO_CHAN_INFO_SAMP_FREQ) {
143 for (i = 0; i < ARRAY_SIZE(tmp007_avgs); i++) {
144 if ((val == tmp007_avgs[i][0]) &&
145 (val2 == tmp007_avgs[i][1])) {
146 tmp = data->config & ~TMP007_CONFIG_CR_MASK;
147 tmp |= (i << TMP007_CONFIG_CR_SHIFT);
148
149 return i2c_smbus_write_word_swapped(data->client,
150 TMP007_CONFIG,
151 data->config = tmp);
152 }
153 }
154 }
155
156 return -EINVAL;
157}
158
159static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");
160
161static struct attribute *tmp007_attributes[] = {
162 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
163 NULL
164};
165
166static const struct attribute_group tmp007_attribute_group = {
167 .attrs = tmp007_attributes,
168};
169
170static const struct iio_chan_spec tmp007_channels[] = {
171 {
172 .type = IIO_TEMP,
173 .modified = 1,
174 .channel2 = IIO_MOD_TEMP_AMBIENT,
175 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
176 BIT(IIO_CHAN_INFO_SCALE),
177 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
178 },
179 {
180 .type = IIO_TEMP,
181 .modified = 1,
182 .channel2 = IIO_MOD_TEMP_OBJECT,
183 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
184 BIT(IIO_CHAN_INFO_SCALE),
185 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
186 }
187};
188
189static const struct iio_info tmp007_info = {
190 .read_raw = tmp007_read_raw,
191 .write_raw = tmp007_write_raw,
192 .attrs = &tmp007_attribute_group,
193 .driver_module = THIS_MODULE,
194};
195
196static bool tmp007_identify(struct i2c_client *client)
197{
198 int manf_id, dev_id;
199
200 manf_id = i2c_smbus_read_word_swapped(client, TMP007_MANUFACTURER_ID);
201 if (manf_id < 0)
202 return false;
203
204 dev_id = i2c_smbus_read_word_swapped(client, TMP007_DEVICE_ID);
205 if (dev_id < 0)
206 return false;
207
208 return (manf_id == TMP007_MANUFACTURER_MAGIC && dev_id == TMP007_DEVICE_MAGIC);
209}
210
211static int tmp007_probe(struct i2c_client *client,
212 const struct i2c_device_id *tmp007_id)
213{
214 struct tmp007_data *data;
215 struct iio_dev *indio_dev;
216 int ret;
217 u16 status;
218
219 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
220 return -EOPNOTSUPP;
221
222 if (!tmp007_identify(client)) {
223 dev_err(&client->dev, "TMP007 not found\n");
224 return -ENODEV;
225 }
226
227 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
228 if (!indio_dev)
229 return -ENOMEM;
230
231 data = iio_priv(indio_dev);
232 i2c_set_clientdata(client, indio_dev);
233 data->client = client;
234
235 indio_dev->dev.parent = &client->dev;
236 indio_dev->name = "tmp007";
237 indio_dev->modes = INDIO_DIRECT_MODE;
238 indio_dev->info = &tmp007_info;
239
240 indio_dev->channels = tmp007_channels;
241 indio_dev->num_channels = ARRAY_SIZE(tmp007_channels);
242
243 /*
244 * Set Configuration register:
245 * 1. Conversion ON
246 * 2. Comparator mode
247 * 3. Transient correction enable
248 */
249
250 ret = i2c_smbus_read_word_swapped(data->client, TMP007_CONFIG);
251 if (ret < 0)
252 return ret;
253
254 data->config = ret;
255 data->config |= (TMP007_CONFIG_CONV_EN | TMP007_CONFIG_COMP_EN | TMP007_CONFIG_TC_EN);
256
257 ret = i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
258 data->config);
259 if (ret < 0)
260 return ret;
261
262 /*
263 * Set Status Mask register:
264 * 1. Conversion ready enable
265 * 2. Data valid enable
266 */
267
268 ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS_MASK);
269 if (ret < 0)
270 goto error_powerdown;
271
272 status = ret;
273 status |= (TMP007_STATUS_CONV_READY | TMP007_STATUS_DATA_VALID);
274
275 ret = i2c_smbus_write_word_swapped(data->client, TMP007_STATUS_MASK, status);
276 if (ret < 0)
277 goto error_powerdown;
278
279 return iio_device_register(indio_dev);
280
281error_powerdown:
282 tmp007_powerdown(data);
283
284 return ret;
285}
286
287static int tmp007_remove(struct i2c_client *client)
288{
289 struct iio_dev *indio_dev = i2c_get_clientdata(client);
290 struct tmp007_data *data = iio_priv(indio_dev);
291
292 iio_device_unregister(indio_dev);
293 tmp007_powerdown(data);
294
295 return 0;
296}
297
298#ifdef CONFIG_PM_SLEEP
299static int tmp007_suspend(struct device *dev)
300{
301 struct tmp007_data *data = iio_priv(i2c_get_clientdata(
302 to_i2c_client(dev)));
303
304 return tmp007_powerdown(data);
305}
306
307static int tmp007_resume(struct device *dev)
308{
309 struct tmp007_data *data = iio_priv(i2c_get_clientdata(
310 to_i2c_client(dev)));
311
312 return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
313 data->config | TMP007_CONFIG_CONV_EN);
314}
315#endif
316
317static SIMPLE_DEV_PM_OPS(tmp007_pm_ops, tmp007_suspend, tmp007_resume);
318
319static const struct of_device_id tmp007_of_match[] = {
320 { .compatible = "ti,tmp007", },
321 { },
322};
323MODULE_DEVICE_TABLE(of, tmp007_of_match);
324
325static const struct i2c_device_id tmp007_id[] = {
326 { "tmp007", 0 },
327 { }
328};
329MODULE_DEVICE_TABLE(i2c, tmp007_id);
330
331static struct i2c_driver tmp007_driver = {
332 .driver = {
333 .name = "tmp007",
334 .of_match_table = of_match_ptr(tmp007_of_match),
335 .pm = &tmp007_pm_ops,
336 },
337 .probe = tmp007_probe,
338 .remove = tmp007_remove,
339 .id_table = tmp007_id,
340};
341module_i2c_driver(tmp007_driver);
342
343MODULE_AUTHOR("Manivannan Sadhasivam <manivannanece23@gmail.com>");
344MODULE_DESCRIPTION("TI TMP007 IR thermopile sensor driver");
345MODULE_LICENSE("GPL");