1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * tsl4531.c - Support for TAOS TSL4531 ambient light sensor
  4 *
  5 * Copyright 2013 Peter Meerwald <pmeerw@pmeerw.net>
  6 *
  7 * IIO driver for the TSL4531x family
  8 *   TSL45311/TSL45313: 7-bit I2C slave address 0x39
  9 *   TSL45315/TSL45317: 7-bit I2C slave address 0x29
 10 *
 11 * TODO: single cycle measurement
 12 */
 13
 14#include <linux/module.h>
 15#include <linux/i2c.h>
 16#include <linux/err.h>
 17#include <linux/delay.h>
 18
 19#include <linux/iio/iio.h>
 20#include <linux/iio/sysfs.h>
 21
 22#define TSL4531_DRV_NAME "tsl4531"
 23
 24#define TSL4531_COMMAND BIT(7)
 25
 26#define TSL4531_CONTROL (TSL4531_COMMAND | 0x00)
 27#define TSL4531_CONFIG (TSL4531_COMMAND | 0x01)
 28#define TSL4531_DATA (TSL4531_COMMAND | 0x04)
 29#define TSL4531_ID (TSL4531_COMMAND | 0x0a)
 30
 31/* operating modes in control register */
 32#define TSL4531_MODE_POWERDOWN 0x00
 33#define TSL4531_MODE_SINGLE_ADC 0x02
 34#define TSL4531_MODE_NORMAL 0x03
 35
 36/* integration time control in config register */
 37#define TSL4531_TCNTRL_400MS 0x00
 38#define TSL4531_TCNTRL_200MS 0x01
 39#define TSL4531_TCNTRL_100MS 0x02
 40
 41/* part number in id register */
 42#define TSL45311_ID 0x8
 43#define TSL45313_ID 0x9
 44#define TSL45315_ID 0xa
 45#define TSL45317_ID 0xb
 46#define TSL4531_ID_SHIFT 4
 47
 48struct tsl4531_data {
 49	struct i2c_client *client;
 50	struct mutex lock;
 51	int int_time;
 52};
 53
 54static IIO_CONST_ATTR_INT_TIME_AVAIL("0.1 0.2 0.4");
 55
 56static struct attribute *tsl4531_attributes[] = {
 57	&iio_const_attr_integration_time_available.dev_attr.attr,
 58	NULL
 59};
 60
 61static const struct attribute_group tsl4531_attribute_group = {
 62	.attrs = tsl4531_attributes,
 63};
 64
 65static const struct iio_chan_spec tsl4531_channels[] = {
 66	{
 67		.type = IIO_LIGHT,
 68		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 69			BIT(IIO_CHAN_INFO_SCALE) |
 70			BIT(IIO_CHAN_INFO_INT_TIME)
 71	}
 72};
 73
 74static int tsl4531_read_raw(struct iio_dev *indio_dev,
 75				struct iio_chan_spec const *chan,
 76				int *val, int *val2, long mask)
 77{
 78	struct tsl4531_data *data = iio_priv(indio_dev);
 79	int ret;
 80
 81	switch (mask) {
 82	case IIO_CHAN_INFO_RAW:
 83		ret = i2c_smbus_read_word_data(data->client,
 84			TSL4531_DATA);
 85		if (ret < 0)
 86			return ret;
 87		*val = ret;
 88		return IIO_VAL_INT;
 89	case IIO_CHAN_INFO_SCALE:
 90		/* 0.. 1x, 1 .. 2x, 2 .. 4x */
 91		*val = 1 << data->int_time;
 92		return IIO_VAL_INT;
 93	case IIO_CHAN_INFO_INT_TIME:
 94		if (data->int_time == 0)
 95			*val2 = 400000;
 96		else if (data->int_time == 1)
 97			*val2 = 200000;
 98		else if (data->int_time == 2)
 99			*val2 = 100000;
100		else
101			return -EINVAL;
102		*val = 0;
103		return IIO_VAL_INT_PLUS_MICRO;
104	default:
105		return -EINVAL;
106	}
107}
108
109static int tsl4531_write_raw(struct iio_dev *indio_dev,
110			     struct iio_chan_spec const *chan,
111			     int val, int val2, long mask)
112{
113	struct tsl4531_data *data = iio_priv(indio_dev);
114	int int_time, ret;
115
116	switch (mask) {
117	case IIO_CHAN_INFO_INT_TIME:
118		if (val != 0)
119			return -EINVAL;
120		if (val2 == 400000)
121			int_time = 0;
122		else if (val2 == 200000)
123			int_time = 1;
124		else if (val2 == 100000)
125			int_time = 2;
126		else
127			return -EINVAL;
128		mutex_lock(&data->lock);
129		ret = i2c_smbus_write_byte_data(data->client,
130			TSL4531_CONFIG, int_time);
131		if (ret >= 0)
132			data->int_time = int_time;
133		mutex_unlock(&data->lock);
134		return ret;
135	default:
136		return -EINVAL;
137	}
138}
139
140static const struct iio_info tsl4531_info = {
141	.read_raw = tsl4531_read_raw,
142	.write_raw = tsl4531_write_raw,
143	.attrs = &tsl4531_attribute_group,
144};
145
146static int tsl4531_check_id(struct i2c_client *client)
147{
148	int ret = i2c_smbus_read_byte_data(client, TSL4531_ID);
149	if (ret < 0)
150		return ret;
151
152	switch (ret >> TSL4531_ID_SHIFT) {
153	case TSL45311_ID:
154	case TSL45313_ID:
155	case TSL45315_ID:
156	case TSL45317_ID:
157		return 0;
158	default:
159		return -ENODEV;
160	}
161}
162
163static int tsl4531_probe(struct i2c_client *client)
164{
165	struct tsl4531_data *data;
166	struct iio_dev *indio_dev;
167	int ret;
168
169	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
170	if (!indio_dev)
171		return -ENOMEM;
172
173	data = iio_priv(indio_dev);
174	i2c_set_clientdata(client, indio_dev);
175	data->client = client;
176	mutex_init(&data->lock);
177
178	ret = tsl4531_check_id(client);
179	if (ret) {
180		dev_err(&client->dev, "no TSL4531 sensor\n");
181		return ret;
182	}
183
184	ret = i2c_smbus_write_byte_data(data->client, TSL4531_CONTROL,
185		TSL4531_MODE_NORMAL);
186	if (ret < 0)
187		return ret;
188
189	ret = i2c_smbus_write_byte_data(data->client, TSL4531_CONFIG,
190		TSL4531_TCNTRL_400MS);
191	if (ret < 0)
192		return ret;
193
194	indio_dev->info = &tsl4531_info;
195	indio_dev->channels = tsl4531_channels;
196	indio_dev->num_channels = ARRAY_SIZE(tsl4531_channels);
197	indio_dev->name = TSL4531_DRV_NAME;
198	indio_dev->modes = INDIO_DIRECT_MODE;
199
200	return iio_device_register(indio_dev);
201}
202
203static int tsl4531_powerdown(struct i2c_client *client)
204{
205	return i2c_smbus_write_byte_data(client, TSL4531_CONTROL,
206		TSL4531_MODE_POWERDOWN);
207}
208
209static void tsl4531_remove(struct i2c_client *client)
210{
211	iio_device_unregister(i2c_get_clientdata(client));
212	tsl4531_powerdown(client);
213}
214
215static int tsl4531_suspend(struct device *dev)
216{
217	return tsl4531_powerdown(to_i2c_client(dev));
218}
219
220static int tsl4531_resume(struct device *dev)
221{
222	return i2c_smbus_write_byte_data(to_i2c_client(dev), TSL4531_CONTROL,
223		TSL4531_MODE_NORMAL);
224}
225
226static DEFINE_SIMPLE_DEV_PM_OPS(tsl4531_pm_ops, tsl4531_suspend,
227				tsl4531_resume);
228
229static const struct i2c_device_id tsl4531_id[] = {
230	{ "tsl4531" },
231	{ }
232};
233MODULE_DEVICE_TABLE(i2c, tsl4531_id);
234
235static struct i2c_driver tsl4531_driver = {
236	.driver = {
237		.name   = TSL4531_DRV_NAME,
238		.pm	= pm_sleep_ptr(&tsl4531_pm_ops),
239	},
240	.probe = tsl4531_probe,
241	.remove = tsl4531_remove,
242	.id_table = tsl4531_id,
243};
244
245module_i2c_driver(tsl4531_driver);
246
247MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
248MODULE_DESCRIPTION("TAOS TSL4531 ambient light sensors driver");
249MODULE_LICENSE("GPL");