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
48 struct tsl4531_data {
49 struct i2c_client *client;
50 struct mutex lock;
51 int int_time;
52 };
53
54 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.1 0.2 0.4");
55
56 static struct attribute *tsl4531_attributes[] = {
57 &iio_const_attr_integration_time_available.dev_attr.attr,
58 NULL
59 };
60
61 static const struct attribute_group tsl4531_attribute_group = {
62 .attrs = tsl4531_attributes,
63 };
64
65 static 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
tsl4531_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)74 static 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
tsl4531_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)109 static 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
140 static 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
tsl4531_check_id(struct i2c_client * client)146 static 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
tsl4531_probe(struct i2c_client * client,const struct i2c_device_id * id)163 static 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
tsl4531_powerdown(struct i2c_client * client)204 static int tsl4531_powerdown(struct i2c_client *client)
205 {
206 return i2c_smbus_write_byte_data(client, TSL4531_CONTROL,
207 TSL4531_MODE_POWERDOWN);
208 }
209
tsl4531_remove(struct i2c_client * client)210 static 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
tsl4531_suspend(struct device * dev)219 static int tsl4531_suspend(struct device *dev)
220 {
221 return tsl4531_powerdown(to_i2c_client(dev));
222 }
223
tsl4531_resume(struct device * dev)224 static 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
230 static 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
236 static const struct i2c_device_id tsl4531_id[] = {
237 { "tsl4531", 0 },
238 { }
239 };
240 MODULE_DEVICE_TABLE(i2c, tsl4531_id);
241
242 static 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
252 module_i2c_driver(tsl4531_driver);
253
254 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
255 MODULE_DESCRIPTION("TAOS TSL4531 ambient light sensors driver");
256 MODULE_LICENSE("GPL");
257