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
55 struct adjd_s311_data {
56 struct i2c_client *client;
57 struct {
58 s16 chans[4];
59 s64 ts __aligned(8);
60 } scan;
61 };
62
63 enum 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
adjd_s311_req_data(struct iio_dev * indio_dev)71 static 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(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(data->client, ADJD_S311_CTRL);
83 if (ret < 0)
84 return ret;
85 if (!(ret & ADJD_S311_CTRL_GSSR))
86 break;
87 msleep(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
adjd_s311_read_data(struct iio_dev * indio_dev,u8 reg,int * val)99 static 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(data->client, reg);
108 if (ret < 0)
109 return ret;
110
111 *val = ret & ADJD_S311_DATA_MASK;
112
113 return 0;
114 }
115
adjd_s311_trigger_handler(int irq,void * p)116 static 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 iio_for_each_active_channel(indio_dev, i) {
129 ret = i2c_smbus_read_word_data(data->client,
130 ADJD_S311_DATA_REG(i));
131 if (ret < 0)
132 goto done;
133
134 data->scan.chans[j++] = ret & ADJD_S311_DATA_MASK;
135 }
136
137 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan, time_ns);
138
139 done:
140 iio_trigger_notify_done(indio_dev->trig);
141
142 return IRQ_HANDLED;
143 }
144
145 #define ADJD_S311_CHANNEL(_color, _scan_idx) { \
146 .type = IIO_INTENSITY, \
147 .modified = 1, \
148 .address = (IDX_##_color), \
149 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
150 BIT(IIO_CHAN_INFO_HARDWAREGAIN) | \
151 BIT(IIO_CHAN_INFO_INT_TIME), \
152 .channel2 = (IIO_MOD_LIGHT_##_color), \
153 .scan_index = (_scan_idx), \
154 .scan_type = { \
155 .sign = 'u', \
156 .realbits = 10, \
157 .storagebits = 16, \
158 .endianness = IIO_CPU, \
159 }, \
160 }
161
162 static const struct iio_chan_spec adjd_s311_channels[] = {
163 ADJD_S311_CHANNEL(RED, 0),
164 ADJD_S311_CHANNEL(GREEN, 1),
165 ADJD_S311_CHANNEL(BLUE, 2),
166 ADJD_S311_CHANNEL(CLEAR, 3),
167 IIO_CHAN_SOFT_TIMESTAMP(4),
168 };
169
adjd_s311_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)170 static int adjd_s311_read_raw(struct iio_dev *indio_dev,
171 struct iio_chan_spec const *chan,
172 int *val, int *val2, long mask)
173 {
174 struct adjd_s311_data *data = iio_priv(indio_dev);
175 int ret;
176
177 switch (mask) {
178 case IIO_CHAN_INFO_RAW:
179 ret = adjd_s311_read_data(indio_dev,
180 ADJD_S311_DATA_REG(chan->address), val);
181 if (ret < 0)
182 return ret;
183 return IIO_VAL_INT;
184 case IIO_CHAN_INFO_HARDWAREGAIN:
185 ret = i2c_smbus_read_byte_data(data->client,
186 ADJD_S311_CAP_REG(chan->address));
187 if (ret < 0)
188 return ret;
189 *val = ret & ADJD_S311_CAP_MASK;
190 return IIO_VAL_INT;
191 case IIO_CHAN_INFO_INT_TIME:
192 ret = i2c_smbus_read_word_data(data->client,
193 ADJD_S311_INT_REG(chan->address));
194 if (ret < 0)
195 return ret;
196 *val = 0;
197 /*
198 * not documented, based on measurement:
199 * 4095 LSBs correspond to roughly 4 ms
200 */
201 *val2 = ret & ADJD_S311_INT_MASK;
202 return IIO_VAL_INT_PLUS_MICRO;
203 }
204 return -EINVAL;
205 }
206
adjd_s311_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)207 static int adjd_s311_write_raw(struct iio_dev *indio_dev,
208 struct iio_chan_spec const *chan,
209 int val, int val2, long mask)
210 {
211 struct adjd_s311_data *data = iio_priv(indio_dev);
212
213 switch (mask) {
214 case IIO_CHAN_INFO_HARDWAREGAIN:
215 if (val < 0 || val > ADJD_S311_CAP_MASK)
216 return -EINVAL;
217
218 return i2c_smbus_write_byte_data(data->client,
219 ADJD_S311_CAP_REG(chan->address), val);
220 case IIO_CHAN_INFO_INT_TIME:
221 if (val != 0 || val2 < 0 || val2 > ADJD_S311_INT_MASK)
222 return -EINVAL;
223
224 return i2c_smbus_write_word_data(data->client,
225 ADJD_S311_INT_REG(chan->address), val2);
226 }
227 return -EINVAL;
228 }
229
230 static const struct iio_info adjd_s311_info = {
231 .read_raw = adjd_s311_read_raw,
232 .write_raw = adjd_s311_write_raw,
233 };
234
adjd_s311_probe(struct i2c_client * client)235 static int adjd_s311_probe(struct i2c_client *client)
236 {
237 struct adjd_s311_data *data;
238 struct iio_dev *indio_dev;
239 int err;
240
241 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
242 if (indio_dev == NULL)
243 return -ENOMEM;
244
245 data = iio_priv(indio_dev);
246 data->client = client;
247
248 indio_dev->info = &adjd_s311_info;
249 indio_dev->name = ADJD_S311_DRV_NAME;
250 indio_dev->channels = adjd_s311_channels;
251 indio_dev->num_channels = ARRAY_SIZE(adjd_s311_channels);
252 indio_dev->modes = INDIO_DIRECT_MODE;
253
254 err = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
255 adjd_s311_trigger_handler, NULL);
256 if (err < 0)
257 return err;
258
259 return devm_iio_device_register(&client->dev, indio_dev);
260 }
261
262 static const struct i2c_device_id adjd_s311_id[] = {
263 { "adjd_s311" },
264 { }
265 };
266 MODULE_DEVICE_TABLE(i2c, adjd_s311_id);
267
268 static struct i2c_driver adjd_s311_driver = {
269 .driver = {
270 .name = ADJD_S311_DRV_NAME,
271 },
272 .probe = adjd_s311_probe,
273 .id_table = adjd_s311_id,
274 };
275 module_i2c_driver(adjd_s311_driver);
276
277 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
278 MODULE_DESCRIPTION("ADJD-S311 color sensor");
279 MODULE_LICENSE("GPL");
280