136edc939SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only
2dfd2ab8dSPeter Meerwald-Stadler /*
3dfd2ab8dSPeter Meerwald-Stadler * veml6070.c - Support for Vishay VEML6070 UV A light sensor
4dfd2ab8dSPeter Meerwald-Stadler *
5dfd2ab8dSPeter Meerwald-Stadler * Copyright 2016 Peter Meerwald-Stadler <pmeerw@pmeerw.net>
6dfd2ab8dSPeter Meerwald-Stadler *
7dfd2ab8dSPeter Meerwald-Stadler * IIO driver for VEML6070 (7-bit I2C slave addresses 0x38 and 0x39)
8dfd2ab8dSPeter Meerwald-Stadler *
9dfd2ab8dSPeter Meerwald-Stadler * TODO: integration time, ACK signal
10dfd2ab8dSPeter Meerwald-Stadler */
11dfd2ab8dSPeter Meerwald-Stadler
12dfd2ab8dSPeter Meerwald-Stadler #include <linux/module.h>
13dfd2ab8dSPeter Meerwald-Stadler #include <linux/i2c.h>
14dfd2ab8dSPeter Meerwald-Stadler #include <linux/mutex.h>
15dfd2ab8dSPeter Meerwald-Stadler #include <linux/err.h>
16dfd2ab8dSPeter Meerwald-Stadler #include <linux/delay.h>
17dfd2ab8dSPeter Meerwald-Stadler
18dfd2ab8dSPeter Meerwald-Stadler #include <linux/iio/iio.h>
19dfd2ab8dSPeter Meerwald-Stadler #include <linux/iio/sysfs.h>
20dfd2ab8dSPeter Meerwald-Stadler
21dfd2ab8dSPeter Meerwald-Stadler #define VEML6070_DRV_NAME "veml6070"
22dfd2ab8dSPeter Meerwald-Stadler
23dfd2ab8dSPeter Meerwald-Stadler #define VEML6070_ADDR_CONFIG_DATA_MSB 0x38 /* read: MSB data, write: config */
24dfd2ab8dSPeter Meerwald-Stadler #define VEML6070_ADDR_DATA_LSB 0x39 /* LSB data */
25dfd2ab8dSPeter Meerwald-Stadler
26dfd2ab8dSPeter Meerwald-Stadler #define VEML6070_COMMAND_ACK BIT(5) /* raise interrupt when over threshold */
27dfd2ab8dSPeter Meerwald-Stadler #define VEML6070_COMMAND_IT GENMASK(3, 2) /* bit mask integration time */
28dfd2ab8dSPeter Meerwald-Stadler #define VEML6070_COMMAND_RSRVD BIT(1) /* reserved, set to 1 */
29dfd2ab8dSPeter Meerwald-Stadler #define VEML6070_COMMAND_SD BIT(0) /* shutdown mode when set */
30dfd2ab8dSPeter Meerwald-Stadler
31dfd2ab8dSPeter Meerwald-Stadler #define VEML6070_IT_10 0x04 /* integration time 1x */
32dfd2ab8dSPeter Meerwald-Stadler
33dfd2ab8dSPeter Meerwald-Stadler struct veml6070_data {
34dfd2ab8dSPeter Meerwald-Stadler struct i2c_client *client1;
35dfd2ab8dSPeter Meerwald-Stadler struct i2c_client *client2;
36dfd2ab8dSPeter Meerwald-Stadler u8 config;
37dfd2ab8dSPeter Meerwald-Stadler struct mutex lock;
38dfd2ab8dSPeter Meerwald-Stadler };
39dfd2ab8dSPeter Meerwald-Stadler
veml6070_read(struct veml6070_data * data)40dfd2ab8dSPeter Meerwald-Stadler static int veml6070_read(struct veml6070_data *data)
41dfd2ab8dSPeter Meerwald-Stadler {
42dfd2ab8dSPeter Meerwald-Stadler int ret;
43dfd2ab8dSPeter Meerwald-Stadler u8 msb, lsb;
44dfd2ab8dSPeter Meerwald-Stadler
45dfd2ab8dSPeter Meerwald-Stadler mutex_lock(&data->lock);
46dfd2ab8dSPeter Meerwald-Stadler
47dfd2ab8dSPeter Meerwald-Stadler /* disable shutdown */
48dfd2ab8dSPeter Meerwald-Stadler ret = i2c_smbus_write_byte(data->client1,
49dfd2ab8dSPeter Meerwald-Stadler data->config & ~VEML6070_COMMAND_SD);
50dfd2ab8dSPeter Meerwald-Stadler if (ret < 0)
51dfd2ab8dSPeter Meerwald-Stadler goto out;
52dfd2ab8dSPeter Meerwald-Stadler
53dfd2ab8dSPeter Meerwald-Stadler msleep(125 + 10); /* measurement takes up to 125 ms for IT 1x */
54dfd2ab8dSPeter Meerwald-Stadler
55dfd2ab8dSPeter Meerwald-Stadler ret = i2c_smbus_read_byte(data->client2); /* read MSB, address 0x39 */
56dfd2ab8dSPeter Meerwald-Stadler if (ret < 0)
57dfd2ab8dSPeter Meerwald-Stadler goto out;
58dfd2ab8dSPeter Meerwald-Stadler msb = ret;
59dfd2ab8dSPeter Meerwald-Stadler
60dfd2ab8dSPeter Meerwald-Stadler ret = i2c_smbus_read_byte(data->client1); /* read LSB, address 0x38 */
61dfd2ab8dSPeter Meerwald-Stadler if (ret < 0)
62dfd2ab8dSPeter Meerwald-Stadler goto out;
63dfd2ab8dSPeter Meerwald-Stadler lsb = ret;
64dfd2ab8dSPeter Meerwald-Stadler
65dfd2ab8dSPeter Meerwald-Stadler /* shutdown again */
66dfd2ab8dSPeter Meerwald-Stadler ret = i2c_smbus_write_byte(data->client1, data->config);
67dfd2ab8dSPeter Meerwald-Stadler if (ret < 0)
68dfd2ab8dSPeter Meerwald-Stadler goto out;
69dfd2ab8dSPeter Meerwald-Stadler
70dfd2ab8dSPeter Meerwald-Stadler ret = (msb << 8) | lsb;
71dfd2ab8dSPeter Meerwald-Stadler
72dfd2ab8dSPeter Meerwald-Stadler out:
73dfd2ab8dSPeter Meerwald-Stadler mutex_unlock(&data->lock);
74dfd2ab8dSPeter Meerwald-Stadler return ret;
75dfd2ab8dSPeter Meerwald-Stadler }
76dfd2ab8dSPeter Meerwald-Stadler
77dfd2ab8dSPeter Meerwald-Stadler static const struct iio_chan_spec veml6070_channels[] = {
78dfd2ab8dSPeter Meerwald-Stadler {
79dfd2ab8dSPeter Meerwald-Stadler .type = IIO_INTENSITY,
80dfd2ab8dSPeter Meerwald-Stadler .modified = 1,
81dfd2ab8dSPeter Meerwald-Stadler .channel2 = IIO_MOD_LIGHT_UV,
82dfd2ab8dSPeter Meerwald-Stadler .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
83dfd2ab8dSPeter Meerwald-Stadler },
84dfd2ab8dSPeter Meerwald-Stadler {
85dfd2ab8dSPeter Meerwald-Stadler .type = IIO_UVINDEX,
86dfd2ab8dSPeter Meerwald-Stadler .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
87dfd2ab8dSPeter Meerwald-Stadler }
88dfd2ab8dSPeter Meerwald-Stadler };
89dfd2ab8dSPeter Meerwald-Stadler
veml6070_to_uv_index(unsigned val)90dfd2ab8dSPeter Meerwald-Stadler static int veml6070_to_uv_index(unsigned val)
91dfd2ab8dSPeter Meerwald-Stadler {
92dfd2ab8dSPeter Meerwald-Stadler /*
93dfd2ab8dSPeter Meerwald-Stadler * conversion of raw UV intensity values to UV index depends on
94dfd2ab8dSPeter Meerwald-Stadler * integration time (IT) and value of the resistor connected to
95dfd2ab8dSPeter Meerwald-Stadler * the RSET pin (default: 270 KOhm)
96dfd2ab8dSPeter Meerwald-Stadler */
97dfd2ab8dSPeter Meerwald-Stadler unsigned uvi[11] = {
98dfd2ab8dSPeter Meerwald-Stadler 187, 373, 560, /* low */
99dfd2ab8dSPeter Meerwald-Stadler 746, 933, 1120, /* moderate */
100dfd2ab8dSPeter Meerwald-Stadler 1308, 1494, /* high */
101dfd2ab8dSPeter Meerwald-Stadler 1681, 1868, 2054}; /* very high */
102dfd2ab8dSPeter Meerwald-Stadler int i;
103dfd2ab8dSPeter Meerwald-Stadler
104dfd2ab8dSPeter Meerwald-Stadler for (i = 0; i < ARRAY_SIZE(uvi); i++)
105dfd2ab8dSPeter Meerwald-Stadler if (val <= uvi[i])
106dfd2ab8dSPeter Meerwald-Stadler return i;
107dfd2ab8dSPeter Meerwald-Stadler
108dfd2ab8dSPeter Meerwald-Stadler return 11; /* extreme */
109dfd2ab8dSPeter Meerwald-Stadler }
110dfd2ab8dSPeter Meerwald-Stadler
veml6070_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)111dfd2ab8dSPeter Meerwald-Stadler static int veml6070_read_raw(struct iio_dev *indio_dev,
112dfd2ab8dSPeter Meerwald-Stadler struct iio_chan_spec const *chan,
113dfd2ab8dSPeter Meerwald-Stadler int *val, int *val2, long mask)
114dfd2ab8dSPeter Meerwald-Stadler {
115dfd2ab8dSPeter Meerwald-Stadler struct veml6070_data *data = iio_priv(indio_dev);
116dfd2ab8dSPeter Meerwald-Stadler int ret;
117dfd2ab8dSPeter Meerwald-Stadler
118dfd2ab8dSPeter Meerwald-Stadler switch (mask) {
119dfd2ab8dSPeter Meerwald-Stadler case IIO_CHAN_INFO_RAW:
120dfd2ab8dSPeter Meerwald-Stadler case IIO_CHAN_INFO_PROCESSED:
121dfd2ab8dSPeter Meerwald-Stadler ret = veml6070_read(data);
122dfd2ab8dSPeter Meerwald-Stadler if (ret < 0)
123dfd2ab8dSPeter Meerwald-Stadler return ret;
124dfd2ab8dSPeter Meerwald-Stadler if (mask == IIO_CHAN_INFO_PROCESSED)
125dfd2ab8dSPeter Meerwald-Stadler *val = veml6070_to_uv_index(ret);
126dfd2ab8dSPeter Meerwald-Stadler else
127dfd2ab8dSPeter Meerwald-Stadler *val = ret;
128dfd2ab8dSPeter Meerwald-Stadler return IIO_VAL_INT;
129dfd2ab8dSPeter Meerwald-Stadler default:
130dfd2ab8dSPeter Meerwald-Stadler return -EINVAL;
131dfd2ab8dSPeter Meerwald-Stadler }
132dfd2ab8dSPeter Meerwald-Stadler }
133dfd2ab8dSPeter Meerwald-Stadler
134dfd2ab8dSPeter Meerwald-Stadler static const struct iio_info veml6070_info = {
135dfd2ab8dSPeter Meerwald-Stadler .read_raw = veml6070_read_raw,
136dfd2ab8dSPeter Meerwald-Stadler };
137dfd2ab8dSPeter Meerwald-Stadler
veml6070_probe(struct i2c_client * client)138f90b8694SUwe Kleine-König static int veml6070_probe(struct i2c_client *client)
139dfd2ab8dSPeter Meerwald-Stadler {
140dfd2ab8dSPeter Meerwald-Stadler struct veml6070_data *data;
141dfd2ab8dSPeter Meerwald-Stadler struct iio_dev *indio_dev;
142dfd2ab8dSPeter Meerwald-Stadler int ret;
143dfd2ab8dSPeter Meerwald-Stadler
144dfd2ab8dSPeter Meerwald-Stadler indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
145dfd2ab8dSPeter Meerwald-Stadler if (!indio_dev)
146dfd2ab8dSPeter Meerwald-Stadler return -ENOMEM;
147dfd2ab8dSPeter Meerwald-Stadler
148dfd2ab8dSPeter Meerwald-Stadler data = iio_priv(indio_dev);
149dfd2ab8dSPeter Meerwald-Stadler i2c_set_clientdata(client, indio_dev);
150dfd2ab8dSPeter Meerwald-Stadler data->client1 = client;
151dfd2ab8dSPeter Meerwald-Stadler mutex_init(&data->lock);
152dfd2ab8dSPeter Meerwald-Stadler
153dfd2ab8dSPeter Meerwald-Stadler indio_dev->info = &veml6070_info;
154dfd2ab8dSPeter Meerwald-Stadler indio_dev->channels = veml6070_channels;
155dfd2ab8dSPeter Meerwald-Stadler indio_dev->num_channels = ARRAY_SIZE(veml6070_channels);
156dfd2ab8dSPeter Meerwald-Stadler indio_dev->name = VEML6070_DRV_NAME;
157dfd2ab8dSPeter Meerwald-Stadler indio_dev->modes = INDIO_DIRECT_MODE;
158dfd2ab8dSPeter Meerwald-Stadler
15948cfd4efSWolfram Sang data->client2 = i2c_new_dummy_device(client->adapter, VEML6070_ADDR_DATA_LSB);
16048cfd4efSWolfram Sang if (IS_ERR(data->client2)) {
161dfd2ab8dSPeter Meerwald-Stadler dev_err(&client->dev, "i2c device for second chip address failed\n");
16248cfd4efSWolfram Sang return PTR_ERR(data->client2);
163dfd2ab8dSPeter Meerwald-Stadler }
164dfd2ab8dSPeter Meerwald-Stadler
165dfd2ab8dSPeter Meerwald-Stadler data->config = VEML6070_IT_10 | VEML6070_COMMAND_RSRVD |
166dfd2ab8dSPeter Meerwald-Stadler VEML6070_COMMAND_SD;
167dfd2ab8dSPeter Meerwald-Stadler ret = i2c_smbus_write_byte(data->client1, data->config);
168dfd2ab8dSPeter Meerwald-Stadler if (ret < 0)
169dfd2ab8dSPeter Meerwald-Stadler goto fail;
170dfd2ab8dSPeter Meerwald-Stadler
171dfd2ab8dSPeter Meerwald-Stadler ret = iio_device_register(indio_dev);
172dfd2ab8dSPeter Meerwald-Stadler if (ret < 0)
173dfd2ab8dSPeter Meerwald-Stadler goto fail;
174dfd2ab8dSPeter Meerwald-Stadler
175dfd2ab8dSPeter Meerwald-Stadler return ret;
176dfd2ab8dSPeter Meerwald-Stadler
177dfd2ab8dSPeter Meerwald-Stadler fail:
178dfd2ab8dSPeter Meerwald-Stadler i2c_unregister_device(data->client2);
179dfd2ab8dSPeter Meerwald-Stadler return ret;
180dfd2ab8dSPeter Meerwald-Stadler }
181dfd2ab8dSPeter Meerwald-Stadler
veml6070_remove(struct i2c_client * client)182ed5c2f5fSUwe Kleine-König static void veml6070_remove(struct i2c_client *client)
183dfd2ab8dSPeter Meerwald-Stadler {
184dfd2ab8dSPeter Meerwald-Stadler struct iio_dev *indio_dev = i2c_get_clientdata(client);
185dfd2ab8dSPeter Meerwald-Stadler struct veml6070_data *data = iio_priv(indio_dev);
186dfd2ab8dSPeter Meerwald-Stadler
187dfd2ab8dSPeter Meerwald-Stadler iio_device_unregister(indio_dev);
188dfd2ab8dSPeter Meerwald-Stadler i2c_unregister_device(data->client2);
189dfd2ab8dSPeter Meerwald-Stadler }
190dfd2ab8dSPeter Meerwald-Stadler
191dfd2ab8dSPeter Meerwald-Stadler static const struct i2c_device_id veml6070_id[] = {
192*4391affaSUwe Kleine-König { "veml6070" },
193dfd2ab8dSPeter Meerwald-Stadler { }
194dfd2ab8dSPeter Meerwald-Stadler };
195dfd2ab8dSPeter Meerwald-Stadler MODULE_DEVICE_TABLE(i2c, veml6070_id);
196dfd2ab8dSPeter Meerwald-Stadler
197dfd2ab8dSPeter Meerwald-Stadler static struct i2c_driver veml6070_driver = {
198dfd2ab8dSPeter Meerwald-Stadler .driver = {
199dfd2ab8dSPeter Meerwald-Stadler .name = VEML6070_DRV_NAME,
200dfd2ab8dSPeter Meerwald-Stadler },
2017cf15f42SUwe Kleine-König .probe = veml6070_probe,
202dfd2ab8dSPeter Meerwald-Stadler .remove = veml6070_remove,
203dfd2ab8dSPeter Meerwald-Stadler .id_table = veml6070_id,
204dfd2ab8dSPeter Meerwald-Stadler };
205dfd2ab8dSPeter Meerwald-Stadler
206dfd2ab8dSPeter Meerwald-Stadler module_i2c_driver(veml6070_driver);
207dfd2ab8dSPeter Meerwald-Stadler
208dfd2ab8dSPeter Meerwald-Stadler MODULE_AUTHOR("Peter Meerwald-Stadler <pmeerw@pmeerw.net>");
209dfd2ab8dSPeter Meerwald-Stadler MODULE_DESCRIPTION("Vishay VEML6070 UV A light sensor driver");
210dfd2ab8dSPeter Meerwald-Stadler MODULE_LICENSE("GPL");
211