1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * adjd_s311.c - Support for ADJD-S311-CR999 digital color sensor
4 *
5 * Copyright (C) 2012 Peter Meerwald <pmeerw@pmeerw.net>
6 *
7 * driver for ADJD-S311-CR999 digital color sensor (10-bit channels for
8 * red, green, blue, clear); 7-bit I2C slave address 0x74
9 *
10 * limitations: no calibration, no offset mode, no sleep mode
11 */
12
13#include <linux/module.h>
14#include <linux/interrupt.h>
15#include <linux/i2c.h>
16#include <linux/slab.h>
17#include <linux/delay.h>
18#include <linux/bitmap.h>
19#include <linux/err.h>
20#include <linux/irq.h>
21
22#include <linux/iio/iio.h>
23#include <linux/iio/sysfs.h>
24#include <linux/iio/trigger_consumer.h>
25#include <linux/iio/buffer.h>
26#include <linux/iio/triggered_buffer.h>
27
28#define ADJD_S311_DRV_NAME "adjd_s311"
29
30#define ADJD_S311_CTRL 0x00
31#define ADJD_S311_CONFIG 0x01
32#define ADJD_S311_CAP_RED 0x06
33#define ADJD_S311_CAP_GREEN 0x07
34#define ADJD_S311_CAP_BLUE 0x08
35#define ADJD_S311_CAP_CLEAR 0x09
36#define ADJD_S311_INT_RED 0x0a
37#define ADJD_S311_INT_GREEN 0x0c
38#define ADJD_S311_INT_BLUE 0x0e
39#define ADJD_S311_INT_CLEAR 0x10
40#define ADJD_S311_DATA_RED 0x40
41#define ADJD_S311_DATA_GREEN 0x42
42#define ADJD_S311_DATA_BLUE 0x44
43#define ADJD_S311_DATA_CLEAR 0x46
44#define ADJD_S311_OFFSET_RED 0x48
45#define ADJD_S311_OFFSET_GREEN 0x49
46#define ADJD_S311_OFFSET_BLUE 0x4a
47#define ADJD_S311_OFFSET_CLEAR 0x4b
48
49#define ADJD_S311_CTRL_GOFS 0x02
50#define ADJD_S311_CTRL_GSSR 0x01
51#define ADJD_S311_CAP_MASK 0x0f
52#define ADJD_S311_INT_MASK 0x0fff
53#define ADJD_S311_DATA_MASK 0x03ff
54
55struct adjd_s311_data {
56 struct i2c_client *client;
57 struct {
58 s16 chans[4];
59 s64 ts __aligned(8);
60 } scan;
61};
62
63enum adjd_s311_channel_idx {
64 IDX_RED, IDX_GREEN, IDX_BLUE, IDX_CLEAR
65};
66
67#define ADJD_S311_DATA_REG(chan) (ADJD_S311_DATA_RED + (chan) * 2)
68#define ADJD_S311_INT_REG(chan) (ADJD_S311_INT_RED + (chan) * 2)
69#define ADJD_S311_CAP_REG(chan) (ADJD_S311_CAP_RED + (chan))
70
71static int adjd_s311_req_data(struct iio_dev *indio_dev)
72{
73 struct adjd_s311_data *data = iio_priv(indio_dev);
74 int tries = 10;
75
76 int ret = i2c_smbus_write_byte_data(client: data->client, ADJD_S311_CTRL,
77 ADJD_S311_CTRL_GSSR);
78 if (ret < 0)
79 return ret;
80
81 while (tries--) {
82 ret = i2c_smbus_read_byte_data(client: data->client, ADJD_S311_CTRL);
83 if (ret < 0)
84 return ret;
85 if (!(ret & ADJD_S311_CTRL_GSSR))
86 break;
87 msleep(msecs: 20);
88 }
89
90 if (tries < 0) {
91 dev_err(&data->client->dev,
92 "adjd_s311_req_data() failed, data not ready\n");
93 return -EIO;
94 }
95
96 return 0;
97}
98
99static int adjd_s311_read_data(struct iio_dev *indio_dev, u8 reg, int *val)
100{
101 struct adjd_s311_data *data = iio_priv(indio_dev);
102
103 int ret = adjd_s311_req_data(indio_dev);
104 if (ret < 0)
105 return ret;
106
107 ret = i2c_smbus_read_word_data(client: data->client, command: reg);
108 if (ret < 0)
109 return ret;
110
111 *val = ret & ADJD_S311_DATA_MASK;
112
113 return 0;
114}
115
116static irqreturn_t adjd_s311_trigger_handler(int irq, void *p)
117{
118 struct iio_poll_func *pf = p;
119 struct iio_dev *indio_dev = pf->indio_dev;
120 struct adjd_s311_data *data = iio_priv(indio_dev);
121 s64 time_ns = iio_get_time_ns(indio_dev);
122 int i, j = 0;
123
124 int ret = adjd_s311_req_data(indio_dev);
125 if (ret < 0)
126 goto done;
127
128 for_each_set_bit(i, indio_dev->active_scan_mask,
129 indio_dev->masklength) {
130 ret = i2c_smbus_read_word_data(client: data->client,
131 ADJD_S311_DATA_REG(i));
132 if (ret < 0)
133 goto done;
134
135 data->scan.chans[j++] = ret & ADJD_S311_DATA_MASK;
136 }
137
138 iio_push_to_buffers_with_timestamp(indio_dev, data: &data->scan, timestamp: time_ns);
139
140done:
141 iio_trigger_notify_done(trig: indio_dev->trig);
142
143 return IRQ_HANDLED;
144}
145
146#define ADJD_S311_CHANNEL(_color, _scan_idx) { \
147 .type = IIO_INTENSITY, \
148 .modified = 1, \
149 .address = (IDX_##_color), \
150 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
151 BIT(IIO_CHAN_INFO_HARDWAREGAIN) | \
152 BIT(IIO_CHAN_INFO_INT_TIME), \
153 .channel2 = (IIO_MOD_LIGHT_##_color), \
154 .scan_index = (_scan_idx), \
155 .scan_type = { \
156 .sign = 'u', \
157 .realbits = 10, \
158 .storagebits = 16, \
159 .endianness = IIO_CPU, \
160 }, \
161}
162
163static const struct iio_chan_spec adjd_s311_channels[] = {
164 ADJD_S311_CHANNEL(RED, 0),
165 ADJD_S311_CHANNEL(GREEN, 1),
166 ADJD_S311_CHANNEL(BLUE, 2),
167 ADJD_S311_CHANNEL(CLEAR, 3),
168 IIO_CHAN_SOFT_TIMESTAMP(4),
169};
170
171static int adjd_s311_read_raw(struct iio_dev *indio_dev,
172 struct iio_chan_spec const *chan,
173 int *val, int *val2, long mask)
174{
175 struct adjd_s311_data *data = iio_priv(indio_dev);
176 int ret;
177
178 switch (mask) {
179 case IIO_CHAN_INFO_RAW:
180 ret = adjd_s311_read_data(indio_dev,
181 ADJD_S311_DATA_REG(chan->address), val);
182 if (ret < 0)
183 return ret;
184 return IIO_VAL_INT;
185 case IIO_CHAN_INFO_HARDWAREGAIN:
186 ret = i2c_smbus_read_byte_data(client: data->client,
187 ADJD_S311_CAP_REG(chan->address));
188 if (ret < 0)
189 return ret;
190 *val = ret & ADJD_S311_CAP_MASK;
191 return IIO_VAL_INT;
192 case IIO_CHAN_INFO_INT_TIME:
193 ret = i2c_smbus_read_word_data(client: data->client,
194 ADJD_S311_INT_REG(chan->address));
195 if (ret < 0)
196 return ret;
197 *val = 0;
198 /*
199 * not documented, based on measurement:
200 * 4095 LSBs correspond to roughly 4 ms
201 */
202 *val2 = ret & ADJD_S311_INT_MASK;
203 return IIO_VAL_INT_PLUS_MICRO;
204 }
205 return -EINVAL;
206}
207
208static int adjd_s311_write_raw(struct iio_dev *indio_dev,
209 struct iio_chan_spec const *chan,
210 int val, int val2, long mask)
211{
212 struct adjd_s311_data *data = iio_priv(indio_dev);
213
214 switch (mask) {
215 case IIO_CHAN_INFO_HARDWAREGAIN:
216 if (val < 0 || val > ADJD_S311_CAP_MASK)
217 return -EINVAL;
218
219 return i2c_smbus_write_byte_data(client: data->client,
220 ADJD_S311_CAP_REG(chan->address), value: val);
221 case IIO_CHAN_INFO_INT_TIME:
222 if (val != 0 || val2 < 0 || val2 > ADJD_S311_INT_MASK)
223 return -EINVAL;
224
225 return i2c_smbus_write_word_data(client: data->client,
226 ADJD_S311_INT_REG(chan->address), value: val2);
227 }
228 return -EINVAL;
229}
230
231static const struct iio_info adjd_s311_info = {
232 .read_raw = adjd_s311_read_raw,
233 .write_raw = adjd_s311_write_raw,
234};
235
236static int adjd_s311_probe(struct i2c_client *client)
237{
238 struct adjd_s311_data *data;
239 struct iio_dev *indio_dev;
240 int err;
241
242 indio_dev = devm_iio_device_alloc(parent: &client->dev, sizeof_priv: sizeof(*data));
243 if (indio_dev == NULL)
244 return -ENOMEM;
245
246 data = iio_priv(indio_dev);
247 data->client = client;
248
249 indio_dev->info = &adjd_s311_info;
250 indio_dev->name = ADJD_S311_DRV_NAME;
251 indio_dev->channels = adjd_s311_channels;
252 indio_dev->num_channels = ARRAY_SIZE(adjd_s311_channels);
253 indio_dev->modes = INDIO_DIRECT_MODE;
254
255 err = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
256 adjd_s311_trigger_handler, NULL);
257 if (err < 0)
258 return err;
259
260 return devm_iio_device_register(&client->dev, indio_dev);
261}
262
263static const struct i2c_device_id adjd_s311_id[] = {
264 { "adjd_s311", 0 },
265 { }
266};
267MODULE_DEVICE_TABLE(i2c, adjd_s311_id);
268
269static struct i2c_driver adjd_s311_driver = {
270 .driver = {
271 .name = ADJD_S311_DRV_NAME,
272 },
273 .probe = adjd_s311_probe,
274 .id_table = adjd_s311_id,
275};
276module_i2c_driver(adjd_s311_driver);
277
278MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
279MODULE_DESCRIPTION("ADJD-S311 color sensor");
280MODULE_LICENSE("GPL");
281

source code of linux/drivers/iio/light/adjd_s311.c