1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * tmp006.c - Support for TI TMP006 IR thermopile sensor
  4 *
  5 * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>
  6 *
  7 * Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
  8 *
  9 * (7-bit I2C slave address 0x40, changeable via ADR pins)
 10 *
 11 * TODO: data ready irq
 12 */
 13
 14#include <linux/err.h>
 15#include <linux/i2c.h>
 16#include <linux/delay.h>
 17#include <linux/module.h>
 18#include <linux/pm.h>
 19#include <linux/bitops.h>
 20
 21#include <linux/iio/iio.h>
 22#include <linux/iio/sysfs.h>
 23
 24#define TMP006_VOBJECT 0x00
 25#define TMP006_TAMBIENT 0x01
 26#define TMP006_CONFIG 0x02
 27#define TMP006_MANUFACTURER_ID 0xfe
 28#define TMP006_DEVICE_ID 0xff
 29
 30#define TMP006_TAMBIENT_SHIFT 2
 31
 32#define TMP006_CONFIG_RESET BIT(15)
 33#define TMP006_CONFIG_DRDY_EN BIT(8)
 34#define TMP006_CONFIG_DRDY BIT(7)
 35
 36#define TMP006_CONFIG_MOD_MASK GENMASK(14, 12)
 37
 38#define TMP006_CONFIG_CR_MASK GENMASK(11, 9)
 39#define TMP006_CONFIG_CR_SHIFT 9
 40
 41#define TMP006_MANUFACTURER_MAGIC 0x5449
 42#define TMP006_DEVICE_MAGIC 0x0067
 43
 44struct tmp006_data {
 45	struct i2c_client *client;
 46	u16 config;
 47};
 48
 49static int tmp006_read_measurement(struct tmp006_data *data, u8 reg)
 50{
 51	s32 ret;
 52	int tries = 50;
 53
 54	while (tries-- > 0) {
 55		ret = i2c_smbus_read_word_swapped(data->client,
 56			TMP006_CONFIG);
 57		if (ret < 0)
 58			return ret;
 59		if (ret & TMP006_CONFIG_DRDY)
 60			break;
 61		msleep(100);
 62	}
 63
 64	if (tries < 0)
 65		return -EIO;
 66
 67	return i2c_smbus_read_word_swapped(data->client, reg);
 68}
 69
 70static const int tmp006_freqs[5][2] = { {4, 0}, {2, 0}, {1, 0},
 71					{0, 500000}, {0, 250000} };
 72
 73static int tmp006_read_raw(struct iio_dev *indio_dev,
 74			    struct iio_chan_spec const *channel, int *val,
 75			    int *val2, long mask)
 76{
 77	struct tmp006_data *data = iio_priv(indio_dev);
 78	s32 ret;
 79	int cr;
 80
 81	switch (mask) {
 82	case IIO_CHAN_INFO_RAW:
 83		if (channel->type == IIO_VOLTAGE) {
 84			/* LSB is 156.25 nV */
 85			ret = tmp006_read_measurement(data, TMP006_VOBJECT);
 86			if (ret < 0)
 87				return ret;
 88			*val = sign_extend32(ret, 15);
 89		} else if (channel->type == IIO_TEMP) {
 90			/* LSB is 0.03125 degrees Celsius */
 91			ret = tmp006_read_measurement(data, TMP006_TAMBIENT);
 92			if (ret < 0)
 93				return ret;
 94			*val = sign_extend32(ret, 15) >> TMP006_TAMBIENT_SHIFT;
 95		} else {
 96			break;
 97		}
 98		return IIO_VAL_INT;
 99	case IIO_CHAN_INFO_SCALE:
100		if (channel->type == IIO_VOLTAGE) {
101			*val = 0;
102			*val2 = 156250;
103		} else if (channel->type == IIO_TEMP) {
104			*val = 31;
105			*val2 = 250000;
106		} else {
107			break;
108		}
109		return IIO_VAL_INT_PLUS_MICRO;
110	case IIO_CHAN_INFO_SAMP_FREQ:
111		cr = (data->config & TMP006_CONFIG_CR_MASK)
112			>> TMP006_CONFIG_CR_SHIFT;
113		*val = tmp006_freqs[cr][0];
114		*val2 = tmp006_freqs[cr][1];
115		return IIO_VAL_INT_PLUS_MICRO;
116	default:
117		break;
118	}
119
120	return -EINVAL;
121}
122
123static int tmp006_write_raw(struct iio_dev *indio_dev,
124			    struct iio_chan_spec const *chan,
125			    int val,
126			    int val2,
127			    long mask)
128{
129	struct tmp006_data *data = iio_priv(indio_dev);
130	int i;
131
132	if (mask != IIO_CHAN_INFO_SAMP_FREQ)
133		return -EINVAL;
134
135	for (i = 0; i < ARRAY_SIZE(tmp006_freqs); i++)
136		if ((val == tmp006_freqs[i][0]) &&
137		    (val2 == tmp006_freqs[i][1])) {
138			data->config &= ~TMP006_CONFIG_CR_MASK;
139			data->config |= i << TMP006_CONFIG_CR_SHIFT;
140
141			return i2c_smbus_write_word_swapped(data->client,
142							    TMP006_CONFIG,
143							    data->config);
144
145		}
146	return -EINVAL;
147}
148
149static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");
150
151static struct attribute *tmp006_attributes[] = {
152	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
153	NULL
154};
155
156static const struct attribute_group tmp006_attribute_group = {
157	.attrs = tmp006_attributes,
158};
159
160static const struct iio_chan_spec tmp006_channels[] = {
161	{
162		.type = IIO_VOLTAGE,
163		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
164			BIT(IIO_CHAN_INFO_SCALE),
165		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
166	},
167	{
168		.type = IIO_TEMP,
169		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
170			BIT(IIO_CHAN_INFO_SCALE),
171		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
172	}
173};
174
175static const struct iio_info tmp006_info = {
176	.read_raw = tmp006_read_raw,
177	.write_raw = tmp006_write_raw,
178	.attrs = &tmp006_attribute_group,
179};
180
181static bool tmp006_check_identification(struct i2c_client *client)
182{
183	int mid, did;
184
185	mid = i2c_smbus_read_word_swapped(client, TMP006_MANUFACTURER_ID);
186	if (mid < 0)
187		return false;
188
189	did = i2c_smbus_read_word_swapped(client, TMP006_DEVICE_ID);
190	if (did < 0)
191		return false;
192
193	return mid == TMP006_MANUFACTURER_MAGIC && did == TMP006_DEVICE_MAGIC;
194}
195
196static int tmp006_probe(struct i2c_client *client,
197			 const struct i2c_device_id *id)
198{
199	struct iio_dev *indio_dev;
200	struct tmp006_data *data;
201	int ret;
202
203	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
204		return -EOPNOTSUPP;
205
206	if (!tmp006_check_identification(client)) {
207		dev_err(&client->dev, "no TMP006 sensor\n");
208		return -ENODEV;
209	}
210
211	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
212	if (!indio_dev)
213		return -ENOMEM;
214
215	data = iio_priv(indio_dev);
216	i2c_set_clientdata(client, indio_dev);
217	data->client = client;
218
219	indio_dev->dev.parent = &client->dev;
220	indio_dev->name = dev_name(&client->dev);
221	indio_dev->modes = INDIO_DIRECT_MODE;
222	indio_dev->info = &tmp006_info;
223
224	indio_dev->channels = tmp006_channels;
225	indio_dev->num_channels = ARRAY_SIZE(tmp006_channels);
226
227	ret = i2c_smbus_read_word_swapped(data->client, TMP006_CONFIG);
228	if (ret < 0)
229		return ret;
230	data->config = ret;
231
232	return iio_device_register(indio_dev);
233}
234
235static int tmp006_powerdown(struct tmp006_data *data)
236{
237	return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
238		data->config & ~TMP006_CONFIG_MOD_MASK);
239}
240
241static int tmp006_remove(struct i2c_client *client)
242{
243	struct iio_dev *indio_dev = i2c_get_clientdata(client);
244
245	iio_device_unregister(indio_dev);
246	tmp006_powerdown(iio_priv(indio_dev));
247
248	return 0;
249}
250
251#ifdef CONFIG_PM_SLEEP
252static int tmp006_suspend(struct device *dev)
253{
254	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
255	return tmp006_powerdown(iio_priv(indio_dev));
256}
257
258static int tmp006_resume(struct device *dev)
259{
260	struct tmp006_data *data = iio_priv(i2c_get_clientdata(
261		to_i2c_client(dev)));
262	return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
263		data->config | TMP006_CONFIG_MOD_MASK);
264}
265#endif
266
267static SIMPLE_DEV_PM_OPS(tmp006_pm_ops, tmp006_suspend, tmp006_resume);
268
269static const struct i2c_device_id tmp006_id[] = {
270	{ "tmp006", 0 },
271	{ }
272};
273MODULE_DEVICE_TABLE(i2c, tmp006_id);
274
275static struct i2c_driver tmp006_driver = {
276	.driver = {
277		.name	= "tmp006",
278		.pm	= &tmp006_pm_ops,
279	},
280	.probe = tmp006_probe,
281	.remove = tmp006_remove,
282	.id_table = tmp006_id,
283};
284module_i2c_driver(tmp006_driver);
285
286MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
287MODULE_DESCRIPTION("TI TMP006 IR thermopile sensor driver");
288MODULE_LICENSE("GPL");