1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * tmp007.c - Support for TI TMP007 IR thermopile sensor with integrated math engine
4 *
5 * Copyright (c) 2017 Manivannan Sadhasivam <manivannanece23@gmail.com>
6 *
7 * Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
8 *
9 * (7-bit I2C slave address (0x40 - 0x47), changeable via ADR pins)
10 *
11 * Note:
12 * 1. This driver assumes that the sensor has been calibrated beforehand
13 * 2. Limit threshold events are enabled at the start
14 * 3. Operating mode: INT
15 */
16
17#include <linux/err.h>
18#include <linux/i2c.h>
19#include <linux/delay.h>
20#include <linux/module.h>
21#include <linux/pm.h>
22#include <linux/bitops.h>
23#include <linux/mod_devicetable.h>
24#include <linux/irq.h>
25#include <linux/interrupt.h>
26
27#include <linux/iio/iio.h>
28#include <linux/iio/sysfs.h>
29#include <linux/iio/events.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_TOBJ_HIGH_LIMIT 0x06
37#define TMP007_TOBJ_LOW_LIMIT 0x07
38#define TMP007_TDIE_HIGH_LIMIT 0x08
39#define TMP007_TDIE_LOW_LIMIT 0x09
40#define TMP007_MANUFACTURER_ID 0x1e
41#define TMP007_DEVICE_ID 0x1f
42
43#define TMP007_CONFIG_CONV_EN BIT(12)
44#define TMP007_CONFIG_TC_EN BIT(6)
45#define TMP007_CONFIG_CR_MASK GENMASK(11, 9)
46#define TMP007_CONFIG_ALERT_EN BIT(8)
47#define TMP007_CONFIG_CR_SHIFT 9
48
49/* Status register flags */
50#define TMP007_STATUS_ALERT BIT(15)
51#define TMP007_STATUS_CONV_READY BIT(14)
52#define TMP007_STATUS_OHF BIT(13)
53#define TMP007_STATUS_OLF BIT(12)
54#define TMP007_STATUS_LHF BIT(11)
55#define TMP007_STATUS_LLF BIT(10)
56#define TMP007_STATUS_DATA_VALID BIT(9)
57
58#define TMP007_MANUFACTURER_MAGIC 0x5449
59#define TMP007_DEVICE_MAGIC 0x0078
60
61#define TMP007_TEMP_SHIFT 2
62
63struct tmp007_data {
64	struct i2c_client *client;
65	struct mutex lock;
66	u16 config;
67	u16 status_mask;
68};
69
70static const int tmp007_avgs[5][2] = { {4, 0}, {2, 0}, {1, 0},
71					{0, 500000}, {0, 250000} };
72
73static int tmp007_read_temperature(struct tmp007_data *data, u8 reg)
74{
75	s32 ret;
76	int tries = 50;
77
78	while (tries-- > 0) {
79		ret = i2c_smbus_read_word_swapped(data->client,
80			TMP007_STATUS);
81		if (ret < 0)
82			return ret;
83		if ((ret & TMP007_STATUS_CONV_READY) &&
84			!(ret & TMP007_STATUS_DATA_VALID))
85				break;
86		msleep(100);
87	}
88
89	if (tries < 0)
90		return -EIO;
91
92	return i2c_smbus_read_word_swapped(data->client, reg);
93}
94
95static int tmp007_powerdown(struct tmp007_data *data)
96{
97	return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
98			data->config & ~TMP007_CONFIG_CONV_EN);
99}
100
101static int tmp007_read_raw(struct iio_dev *indio_dev,
102		struct iio_chan_spec const *channel, int *val,
103		int *val2, long mask)
104{
105	struct tmp007_data *data = iio_priv(indio_dev);
106	s32 ret;
107	int conv_rate;
108
109	switch (mask) {
110	case IIO_CHAN_INFO_RAW:
111		switch (channel->channel2) {
112		case IIO_MOD_TEMP_AMBIENT: /* LSB: 0.03125 degree Celsius */
113			ret = i2c_smbus_read_word_swapped(data->client, TMP007_TDIE);
114			if (ret < 0)
115				return ret;
116			break;
117		case IIO_MOD_TEMP_OBJECT:
118			ret = tmp007_read_temperature(data, TMP007_TOBJECT);
119			if (ret < 0)
120				return ret;
121			break;
122		default:
123			return -EINVAL;
124		}
125
126		*val = sign_extend32(ret, 15) >> TMP007_TEMP_SHIFT;
127
128		return IIO_VAL_INT;
129	case IIO_CHAN_INFO_SCALE:
130		*val = 31;
131		*val2 = 250000;
132
133		return IIO_VAL_INT_PLUS_MICRO;
134	case IIO_CHAN_INFO_SAMP_FREQ:
135		conv_rate = (data->config & TMP007_CONFIG_CR_MASK)
136				>> TMP007_CONFIG_CR_SHIFT;
137		*val = tmp007_avgs[conv_rate][0];
138		*val2 = tmp007_avgs[conv_rate][1];
139
140		return IIO_VAL_INT_PLUS_MICRO;
141	default:
142		return -EINVAL;
143	}
144}
145
146static int tmp007_write_raw(struct iio_dev *indio_dev,
147		struct iio_chan_spec const *channel, int val,
148		int val2, long mask)
149{
150	struct tmp007_data *data = iio_priv(indio_dev);
151	int i;
152	u16 tmp;
153
154	if (mask == IIO_CHAN_INFO_SAMP_FREQ) {
155		for (i = 0; i < ARRAY_SIZE(tmp007_avgs); i++) {
156			if ((val == tmp007_avgs[i][0]) &&
157			(val2 == tmp007_avgs[i][1])) {
158				tmp = data->config & ~TMP007_CONFIG_CR_MASK;
159				tmp |= (i << TMP007_CONFIG_CR_SHIFT);
160
161				return i2c_smbus_write_word_swapped(data->client,
162								TMP007_CONFIG,
163								data->config = tmp);
164			}
165		}
166	}
167
168	return -EINVAL;
169}
170
171static irqreturn_t tmp007_interrupt_handler(int irq, void *private)
172{
173	struct iio_dev *indio_dev = private;
174	struct tmp007_data *data = iio_priv(indio_dev);
175	int ret;
176
177	ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS);
178	if ((ret < 0) || !(ret & (TMP007_STATUS_OHF | TMP007_STATUS_OLF |
179				TMP007_STATUS_LHF | TMP007_STATUS_LLF)))
180		return IRQ_NONE;
181
182	if (ret & TMP007_STATUS_OHF)
183		iio_push_event(indio_dev,
184				IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
185					IIO_MOD_TEMP_OBJECT,
186					IIO_EV_TYPE_THRESH,
187					IIO_EV_DIR_RISING),
188				iio_get_time_ns(indio_dev));
189
190	if (ret & TMP007_STATUS_OLF)
191		iio_push_event(indio_dev,
192				IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
193					IIO_MOD_TEMP_OBJECT,
194					IIO_EV_TYPE_THRESH,
195					IIO_EV_DIR_FALLING),
196				iio_get_time_ns(indio_dev));
197
198	if (ret & TMP007_STATUS_LHF)
199		iio_push_event(indio_dev,
200				IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
201					IIO_MOD_TEMP_AMBIENT,
202					IIO_EV_TYPE_THRESH,
203					IIO_EV_DIR_RISING),
204				iio_get_time_ns(indio_dev));
205
206	if (ret & TMP007_STATUS_LLF)
207		iio_push_event(indio_dev,
208				IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
209					IIO_MOD_TEMP_AMBIENT,
210					IIO_EV_TYPE_THRESH,
211					IIO_EV_DIR_FALLING),
212				iio_get_time_ns(indio_dev));
213
214	return IRQ_HANDLED;
215}
216
217static int tmp007_write_event_config(struct iio_dev *indio_dev,
218		const struct iio_chan_spec *chan, enum iio_event_type type,
219		enum iio_event_direction dir, int state)
220{
221	struct tmp007_data *data = iio_priv(indio_dev);
222	unsigned int status_mask;
223	int ret;
224
225	switch (chan->channel2) {
226	case IIO_MOD_TEMP_AMBIENT:
227	if (dir == IIO_EV_DIR_RISING)
228			status_mask = TMP007_STATUS_LHF;
229		else
230			status_mask = TMP007_STATUS_LLF;
231		break;
232	case IIO_MOD_TEMP_OBJECT:
233		if (dir == IIO_EV_DIR_RISING)
234			status_mask = TMP007_STATUS_OHF;
235		else
236			status_mask = TMP007_STATUS_OLF;
237		break;
238	default:
239		return -EINVAL;
240	}
241
242	mutex_lock(&data->lock);
243	ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS_MASK);
244	mutex_unlock(&data->lock);
245	if (ret < 0)
246		return ret;
247
248	if (state)
249		ret |= status_mask;
250	else
251		ret &= ~status_mask;
252
253	return i2c_smbus_write_word_swapped(data->client, TMP007_STATUS_MASK,
254					data->status_mask = ret);
255}
256
257static int tmp007_read_event_config(struct iio_dev *indio_dev,
258		const struct iio_chan_spec *chan, enum iio_event_type type,
259		enum iio_event_direction dir)
260{
261	struct tmp007_data *data = iio_priv(indio_dev);
262	unsigned int mask;
263
264	switch (chan->channel2) {
265	case IIO_MOD_TEMP_AMBIENT:
266		if (dir == IIO_EV_DIR_RISING)
267			mask = TMP007_STATUS_LHF;
268		else
269			mask = TMP007_STATUS_LLF;
270		break;
271	case IIO_MOD_TEMP_OBJECT:
272		if (dir == IIO_EV_DIR_RISING)
273			mask = TMP007_STATUS_OHF;
274		else
275			mask = TMP007_STATUS_OLF;
276		break;
277	default:
278		return -EINVAL;
279	}
280
281	return !!(data->status_mask & mask);
282}
283
284static int tmp007_read_thresh(struct iio_dev *indio_dev,
285		const struct iio_chan_spec *chan, enum iio_event_type type,
286		enum iio_event_direction dir, enum iio_event_info info,
287		int *val, int *val2)
288{
289	struct tmp007_data *data = iio_priv(indio_dev);
290	int ret;
291	u8 reg;
292
293	switch (chan->channel2) {
294	case IIO_MOD_TEMP_AMBIENT: /* LSB: 0.5 degree Celsius */
295		if (dir == IIO_EV_DIR_RISING)
296			reg = TMP007_TDIE_HIGH_LIMIT;
297		else
298			reg = TMP007_TDIE_LOW_LIMIT;
299		break;
300	case IIO_MOD_TEMP_OBJECT:
301		if (dir == IIO_EV_DIR_RISING)
302			reg = TMP007_TOBJ_HIGH_LIMIT;
303	else
304			reg = TMP007_TOBJ_LOW_LIMIT;
305		break;
306	default:
307		return -EINVAL;
308	}
309
310	ret = i2c_smbus_read_word_swapped(data->client, reg);
311	if (ret < 0)
312		return ret;
313
314	/* Shift length 7 bits = 6(15:6) + 1(0.5 LSB) */
315	*val = sign_extend32(ret, 15) >> 7;
316
317	return IIO_VAL_INT;
318}
319
320static int tmp007_write_thresh(struct iio_dev *indio_dev,
321		const struct iio_chan_spec *chan, enum iio_event_type type,
322		enum iio_event_direction dir, enum iio_event_info info,
323		int val, int val2)
324{
325	struct tmp007_data *data = iio_priv(indio_dev);
326	u8 reg;
327
328	switch (chan->channel2) {
329	case IIO_MOD_TEMP_AMBIENT:
330		if (dir == IIO_EV_DIR_RISING)
331			reg = TMP007_TDIE_HIGH_LIMIT;
332		else
333			reg = TMP007_TDIE_LOW_LIMIT;
334		break;
335	case IIO_MOD_TEMP_OBJECT:
336		if (dir == IIO_EV_DIR_RISING)
337			reg = TMP007_TOBJ_HIGH_LIMIT;
338		else
339			reg = TMP007_TOBJ_LOW_LIMIT;
340		break;
341	default:
342		return -EINVAL;
343	}
344
345	/* Full scale threshold value is +/- 256 degree Celsius */
346	if (val < -256 || val > 255)
347		return -EINVAL;
348
349	/* Shift length 7 bits = 6(15:6) + 1(0.5 LSB) */
350	return i2c_smbus_write_word_swapped(data->client, reg, (val << 7));
351}
352
353static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");
354
355static struct attribute *tmp007_attributes[] = {
356	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
357	NULL
358};
359
360static const struct attribute_group tmp007_attribute_group = {
361	.attrs = tmp007_attributes,
362};
363
364static const struct iio_event_spec tmp007_obj_event[] = {
365	{
366		.type = IIO_EV_TYPE_THRESH,
367		.dir = IIO_EV_DIR_RISING,
368		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
369			BIT(IIO_EV_INFO_ENABLE),
370	},
371	{
372		.type = IIO_EV_TYPE_THRESH,
373		.dir = IIO_EV_DIR_FALLING,
374		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
375			BIT(IIO_EV_INFO_ENABLE),
376	},
377};
378
379static const struct iio_event_spec tmp007_die_event[] = {
380	{
381		.type = IIO_EV_TYPE_THRESH,
382		.dir = IIO_EV_DIR_RISING,
383		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
384			BIT(IIO_EV_INFO_ENABLE),
385	},
386	{
387		.type = IIO_EV_TYPE_THRESH,
388		.dir = IIO_EV_DIR_FALLING,
389		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
390			BIT(IIO_EV_INFO_ENABLE),
391	},
392};
393
394static const struct iio_chan_spec tmp007_channels[] = {
395	{
396		.type = IIO_TEMP,
397		.modified = 1,
398		.channel2 = IIO_MOD_TEMP_AMBIENT,
399		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
400				BIT(IIO_CHAN_INFO_SCALE),
401		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
402		.event_spec = tmp007_die_event,
403		.num_event_specs = ARRAY_SIZE(tmp007_die_event),
404	},
405	{
406		.type = IIO_TEMP,
407		.modified = 1,
408		.channel2 = IIO_MOD_TEMP_OBJECT,
409		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
410				BIT(IIO_CHAN_INFO_SCALE),
411		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
412		.event_spec = tmp007_obj_event,
413		.num_event_specs = ARRAY_SIZE(tmp007_obj_event),
414	}
415};
416
417static const struct iio_info tmp007_info = {
418	.read_raw = tmp007_read_raw,
419	.write_raw = tmp007_write_raw,
420	.read_event_config = tmp007_read_event_config,
421	.write_event_config = tmp007_write_event_config,
422	.read_event_value = tmp007_read_thresh,
423	.write_event_value = tmp007_write_thresh,
424	.attrs = &tmp007_attribute_group,
425};
426
427static bool tmp007_identify(struct i2c_client *client)
428{
429	int manf_id, dev_id;
430
431	manf_id = i2c_smbus_read_word_swapped(client, TMP007_MANUFACTURER_ID);
432	if (manf_id < 0)
433		return false;
434
435	dev_id = i2c_smbus_read_word_swapped(client, TMP007_DEVICE_ID);
436	if (dev_id < 0)
437		return false;
438
439	return (manf_id == TMP007_MANUFACTURER_MAGIC && dev_id == TMP007_DEVICE_MAGIC);
440}
441
442static int tmp007_probe(struct i2c_client *client,
443			const struct i2c_device_id *tmp007_id)
444{
445	struct tmp007_data *data;
446	struct iio_dev *indio_dev;
447	int ret;
448
449	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
450		return -EOPNOTSUPP;
451
452	if (!tmp007_identify(client)) {
453		dev_err(&client->dev, "TMP007 not found\n");
454		return -ENODEV;
455	}
456
457	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
458	if (!indio_dev)
459		return -ENOMEM;
460
461	data = iio_priv(indio_dev);
462	i2c_set_clientdata(client, indio_dev);
463	data->client = client;
464	mutex_init(&data->lock);
465
466	indio_dev->name = "tmp007";
467	indio_dev->modes = INDIO_DIRECT_MODE;
468	indio_dev->info = &tmp007_info;
469
470	indio_dev->channels = tmp007_channels;
471	indio_dev->num_channels = ARRAY_SIZE(tmp007_channels);
472
473	/*
474	 * Set Configuration register:
475	 * 1. Conversion ON
476	 * 2. ALERT enable
477	 * 3. Transient correction enable
478	 */
479
480	ret = i2c_smbus_read_word_swapped(data->client, TMP007_CONFIG);
481	if (ret < 0)
482		return ret;
483
484	data->config = ret;
485	data->config |= (TMP007_CONFIG_CONV_EN | TMP007_CONFIG_ALERT_EN | TMP007_CONFIG_TC_EN);
486
487	ret = i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
488					data->config);
489	if (ret < 0)
490		return ret;
491
492	/*
493	 * Only the following flags can activate ALERT pin. Data conversion/validity flags
494	 * flags can still be polled for getting temperature data
495	 *
496	 * Set Status Mask register:
497	 * 1. Object temperature high limit enable
498	 * 2. Object temperature low limit enable
499	 * 3. TDIE temperature high limit enable
500	 * 4. TDIE temperature low limit enable
501	 */
502
503	ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS_MASK);
504	if (ret < 0)
505		goto error_powerdown;
506
507	data->status_mask = ret;
508	data->status_mask |= (TMP007_STATUS_OHF | TMP007_STATUS_OLF
509				| TMP007_STATUS_LHF | TMP007_STATUS_LLF);
510
511	ret = i2c_smbus_write_word_swapped(data->client, TMP007_STATUS_MASK, data->status_mask);
512	if (ret < 0)
513		goto error_powerdown;
514
515	if (client->irq) {
516		ret = devm_request_threaded_irq(&client->dev, client->irq,
517				NULL, tmp007_interrupt_handler,
518				IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
519				tmp007_id->name, indio_dev);
520		if (ret) {
521			dev_err(&client->dev, "irq request error %d\n", -ret);
522			goto error_powerdown;
523		}
524	}
525
526	return iio_device_register(indio_dev);
527
528error_powerdown:
529	tmp007_powerdown(data);
530
531	return ret;
532}
533
534static int tmp007_remove(struct i2c_client *client)
535{
536	struct iio_dev *indio_dev = i2c_get_clientdata(client);
537	struct tmp007_data *data = iio_priv(indio_dev);
538
539	iio_device_unregister(indio_dev);
540	tmp007_powerdown(data);
541
542	return 0;
543}
544
545#ifdef CONFIG_PM_SLEEP
546static int tmp007_suspend(struct device *dev)
547{
548	struct tmp007_data *data = iio_priv(i2c_get_clientdata(
549			to_i2c_client(dev)));
550
551	return tmp007_powerdown(data);
552}
553
554static int tmp007_resume(struct device *dev)
555{
556	struct tmp007_data *data = iio_priv(i2c_get_clientdata(
557			to_i2c_client(dev)));
558
559	return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
560			data->config | TMP007_CONFIG_CONV_EN);
561}
562#endif
563
564static SIMPLE_DEV_PM_OPS(tmp007_pm_ops, tmp007_suspend, tmp007_resume);
565
566static const struct of_device_id tmp007_of_match[] = {
567	{ .compatible = "ti,tmp007", },
568	{ },
569};
570MODULE_DEVICE_TABLE(of, tmp007_of_match);
571
572static const struct i2c_device_id tmp007_id[] = {
573	{ "tmp007", 0 },
574	{ }
575};
576MODULE_DEVICE_TABLE(i2c, tmp007_id);
577
578static struct i2c_driver tmp007_driver = {
579	.driver = {
580		.name	= "tmp007",
581		.of_match_table = tmp007_of_match,
582		.pm	= &tmp007_pm_ops,
583	},
584	.probe		= tmp007_probe,
585	.remove		= tmp007_remove,
586	.id_table	= tmp007_id,
587};
588module_i2c_driver(tmp007_driver);
589
590MODULE_AUTHOR("Manivannan Sadhasivam <manivannanece23@gmail.com>");
591MODULE_DESCRIPTION("TI TMP007 IR thermopile sensor driver");
592MODULE_LICENSE("GPL");
593