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			  const struct i2c_device_id *id)
165{
166	struct tsl4531_data *data;
167	struct iio_dev *indio_dev;
168	int ret;
169
170	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
171	if (!indio_dev)
172		return -ENOMEM;
173
174	data = iio_priv(indio_dev);
175	i2c_set_clientdata(client, indio_dev);
176	data->client = client;
177	mutex_init(&data->lock);
178
179	ret = tsl4531_check_id(client);
180	if (ret) {
181		dev_err(&client->dev, "no TSL4531 sensor\n");
182		return ret;
183	}
184
185	ret = i2c_smbus_write_byte_data(data->client, TSL4531_CONTROL,
186		TSL4531_MODE_NORMAL);
187	if (ret < 0)
188		return ret;
189
190	ret = i2c_smbus_write_byte_data(data->client, TSL4531_CONFIG,
191		TSL4531_TCNTRL_400MS);
192	if (ret < 0)
193		return ret;
194
195	indio_dev->info = &tsl4531_info;
196	indio_dev->channels = tsl4531_channels;
197	indio_dev->num_channels = ARRAY_SIZE(tsl4531_channels);
198	indio_dev->name = TSL4531_DRV_NAME;
199	indio_dev->modes = INDIO_DIRECT_MODE;
200
201	return iio_device_register(indio_dev);
202}
203
204static int tsl4531_powerdown(struct i2c_client *client)
205{
206	return i2c_smbus_write_byte_data(client, TSL4531_CONTROL,
207		TSL4531_MODE_POWERDOWN);
208}
209
210static int tsl4531_remove(struct i2c_client *client)
211{
212	iio_device_unregister(i2c_get_clientdata(client));
213	tsl4531_powerdown(client);
214
215	return 0;
216}
217
218#ifdef CONFIG_PM_SLEEP
219static int tsl4531_suspend(struct device *dev)
220{
221	return tsl4531_powerdown(to_i2c_client(dev));
222}
223
224static int tsl4531_resume(struct device *dev)
225{
226	return i2c_smbus_write_byte_data(to_i2c_client(dev), TSL4531_CONTROL,
227		TSL4531_MODE_NORMAL);
228}
229
230static SIMPLE_DEV_PM_OPS(tsl4531_pm_ops, tsl4531_suspend, tsl4531_resume);
231#define TSL4531_PM_OPS (&tsl4531_pm_ops)
232#else
233#define TSL4531_PM_OPS NULL
234#endif
235
236static const struct i2c_device_id tsl4531_id[] = {
237	{ "tsl4531", 0 },
238	{ }
239};
240MODULE_DEVICE_TABLE(i2c, tsl4531_id);
241
242static struct i2c_driver tsl4531_driver = {
243	.driver = {
244		.name   = TSL4531_DRV_NAME,
245		.pm	= TSL4531_PM_OPS,
246	},
247	.probe  = tsl4531_probe,
248	.remove = tsl4531_remove,
249	.id_table = tsl4531_id,
250};
251
252module_i2c_driver(tsl4531_driver);
253
254MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
255MODULE_DESCRIPTION("TAOS TSL4531 ambient light sensors driver");
256MODULE_LICENSE("GPL");