tmp007.c

  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, bool 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 void tmp007_powerdown_action_cb(void *priv)
443{
444	struct tmp007_data *data = priv;
445
446	tmp007_powerdown(data);
447}
448
449static int tmp007_probe(struct i2c_client *client)
450{
451	const struct i2c_device_id *tmp007_id = i2c_client_get_device_id(client);
452	struct tmp007_data *data;
453	struct iio_dev *indio_dev;
454	int ret;
455
456	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
457		return -EOPNOTSUPP;
458
459	if (!tmp007_identify(client)) {
460		dev_err(&client->dev, "TMP007 not found\n");
461		return -ENODEV;
462	}
463
464	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
465	if (!indio_dev)
466		return -ENOMEM;
467
468	data = iio_priv(indio_dev);
469	i2c_set_clientdata(client, indio_dev);
470	data->client = client;
471	mutex_init(&data->lock);
472
473	indio_dev->name = "tmp007";
474	indio_dev->modes = INDIO_DIRECT_MODE;
475	indio_dev->info = &tmp007_info;
476
477	indio_dev->channels = tmp007_channels;
478	indio_dev->num_channels = ARRAY_SIZE(tmp007_channels);
479
480	/*
481	 * Set Configuration register:
482	 * 1. Conversion ON
483	 * 2. ALERT enable
484	 * 3. Transient correction enable
485	 */
486
487	ret = i2c_smbus_read_word_swapped(data->client, TMP007_CONFIG);
488	if (ret < 0)
489		return ret;
490
491	data->config = ret;
492	data->config |= (TMP007_CONFIG_CONV_EN | TMP007_CONFIG_ALERT_EN | TMP007_CONFIG_TC_EN);
493
494	ret = i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
495					data->config);
496	if (ret < 0)
497		return ret;
498
499	ret = devm_add_action_or_reset(&client->dev, tmp007_powerdown_action_cb, data);
500	if (ret)
501		return ret;
502
503	/*
504	 * Only the following flags can activate ALERT pin. Data conversion/validity flags
505	 * flags can still be polled for getting temperature data
506	 *
507	 * Set Status Mask register:
508	 * 1. Object temperature high limit enable
509	 * 2. Object temperature low limit enable
510	 * 3. TDIE temperature high limit enable
511	 * 4. TDIE temperature low limit enable
512	 */
513
514	ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS_MASK);
515	if (ret < 0)
516		return ret;
517
518	data->status_mask = ret;
519	data->status_mask |= (TMP007_STATUS_OHF | TMP007_STATUS_OLF
520				| TMP007_STATUS_LHF | TMP007_STATUS_LLF);
521
522	ret = i2c_smbus_write_word_swapped(data->client, TMP007_STATUS_MASK, data->status_mask);
523	if (ret < 0)
524		return ret;
525
526	if (client->irq) {
527		ret = devm_request_threaded_irq(&client->dev, client->irq,
528				NULL, tmp007_interrupt_handler,
529				IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
530				tmp007_id->name, indio_dev);
531		if (ret) {
532			dev_err(&client->dev, "irq request error %d\n", -ret);
533			return ret;
534		}
535	}
536
537	return devm_iio_device_register(&client->dev, indio_dev);
538}
539
540static int tmp007_suspend(struct device *dev)
541{
542	struct tmp007_data *data = iio_priv(i2c_get_clientdata(
543			to_i2c_client(dev)));
544
545	return tmp007_powerdown(data);
546}
547
548static int tmp007_resume(struct device *dev)
549{
550	struct tmp007_data *data = iio_priv(i2c_get_clientdata(
551			to_i2c_client(dev)));
552
553	return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
554			data->config | TMP007_CONFIG_CONV_EN);
555}
556
557static DEFINE_SIMPLE_DEV_PM_OPS(tmp007_pm_ops, tmp007_suspend, tmp007_resume);
558
559static const struct of_device_id tmp007_of_match[] = {
560	{ .compatible = "ti,tmp007", },
561	{ }
562};
563MODULE_DEVICE_TABLE(of, tmp007_of_match);
564
565static const struct i2c_device_id tmp007_id[] = {
566	{ "tmp007" },
567	{ }
568};
569MODULE_DEVICE_TABLE(i2c, tmp007_id);
570
571static struct i2c_driver tmp007_driver = {
572	.driver = {
573		.name	= "tmp007",
574		.of_match_table = tmp007_of_match,
575		.pm	= pm_sleep_ptr(&tmp007_pm_ops),
576	},
577	.probe		= tmp007_probe,
578	.id_table	= tmp007_id,
579};
580module_i2c_driver(tmp007_driver);
581
582MODULE_AUTHOR("Manivannan Sadhasivam <manivannanece23@gmail.com>");
583MODULE_DESCRIPTION("TI TMP007 IR thermopile sensor driver");
584MODULE_LICENSE("GPL");