1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * tcs3414.c - Support for TAOS TCS3414 digital color sensor
4 *
5 * Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
6 *
7 * Digital color sensor with 16-bit channels for red, green, blue, clear);
8 * 7-bit I2C slave address 0x39 (TCS3414) or 0x29, 0x49, 0x59 (TCS3413,
9 * TCS3415, TCS3416, resp.)
10 *
11 * TODO: sync, interrupt support, thresholds, prescaler
12 */
13
14 #include <linux/module.h>
15 #include <linux/i2c.h>
16 #include <linux/delay.h>
17 #include <linux/pm.h>
18
19 #include <linux/iio/iio.h>
20 #include <linux/iio/sysfs.h>
21 #include <linux/iio/trigger_consumer.h>
22 #include <linux/iio/buffer.h>
23 #include <linux/iio/triggered_buffer.h>
24
25 #define TCS3414_DRV_NAME "tcs3414"
26
27 #define TCS3414_COMMAND BIT(7)
28 #define TCS3414_COMMAND_WORD (TCS3414_COMMAND | BIT(5))
29
30 #define TCS3414_CONTROL (TCS3414_COMMAND | 0x00)
31 #define TCS3414_TIMING (TCS3414_COMMAND | 0x01)
32 #define TCS3414_ID (TCS3414_COMMAND | 0x04)
33 #define TCS3414_GAIN (TCS3414_COMMAND | 0x07)
34 #define TCS3414_DATA_GREEN (TCS3414_COMMAND_WORD | 0x10)
35 #define TCS3414_DATA_RED (TCS3414_COMMAND_WORD | 0x12)
36 #define TCS3414_DATA_BLUE (TCS3414_COMMAND_WORD | 0x14)
37 #define TCS3414_DATA_CLEAR (TCS3414_COMMAND_WORD | 0x16)
38
39 #define TCS3414_CONTROL_ADC_VALID BIT(4)
40 #define TCS3414_CONTROL_ADC_EN BIT(1)
41 #define TCS3414_CONTROL_POWER BIT(0)
42
43 #define TCS3414_INTEG_MASK GENMASK(1, 0)
44 #define TCS3414_INTEG_12MS 0x0
45 #define TCS3414_INTEG_100MS 0x1
46 #define TCS3414_INTEG_400MS 0x2
47
48 #define TCS3414_GAIN_MASK GENMASK(5, 4)
49 #define TCS3414_GAIN_SHIFT 4
50
51 struct tcs3414_data {
52 struct i2c_client *client;
53 u8 control;
54 u8 gain;
55 u8 timing;
56 u16 buffer[8]; /* 4x 16-bit + 8 bytes timestamp */
57 };
58
59 #define TCS3414_CHANNEL(_color, _si, _addr) { \
60 .type = IIO_INTENSITY, \
61 .modified = 1, \
62 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
63 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
64 BIT(IIO_CHAN_INFO_INT_TIME), \
65 .channel2 = IIO_MOD_LIGHT_##_color, \
66 .address = _addr, \
67 .scan_index = _si, \
68 .scan_type = { \
69 .sign = 'u', \
70 .realbits = 16, \
71 .storagebits = 16, \
72 .endianness = IIO_CPU, \
73 }, \
74 }
75
76 /* scale factors: 1/gain */
77 static const int tcs3414_scales[][2] = {
78 {1, 0}, {0, 250000}, {0, 62500}, {0, 15625}
79 };
80
81 /* integration time in ms */
82 static const int tcs3414_times[] = { 12, 100, 400 };
83
84 static const struct iio_chan_spec tcs3414_channels[] = {
85 TCS3414_CHANNEL(GREEN, 0, TCS3414_DATA_GREEN),
86 TCS3414_CHANNEL(RED, 1, TCS3414_DATA_RED),
87 TCS3414_CHANNEL(BLUE, 2, TCS3414_DATA_BLUE),
88 TCS3414_CHANNEL(CLEAR, 3, TCS3414_DATA_CLEAR),
89 IIO_CHAN_SOFT_TIMESTAMP(4),
90 };
91
tcs3414_req_data(struct tcs3414_data * data)92 static int tcs3414_req_data(struct tcs3414_data *data)
93 {
94 int tries = 25;
95 int ret;
96
97 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
98 data->control | TCS3414_CONTROL_ADC_EN);
99 if (ret < 0)
100 return ret;
101
102 while (tries--) {
103 ret = i2c_smbus_read_byte_data(data->client, TCS3414_CONTROL);
104 if (ret < 0)
105 return ret;
106 if (ret & TCS3414_CONTROL_ADC_VALID)
107 break;
108 msleep(20);
109 }
110
111 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
112 data->control);
113 if (ret < 0)
114 return ret;
115
116 if (tries < 0) {
117 dev_err(&data->client->dev, "data not ready\n");
118 return -EIO;
119 }
120
121 return 0;
122 }
123
tcs3414_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)124 static int tcs3414_read_raw(struct iio_dev *indio_dev,
125 struct iio_chan_spec const *chan,
126 int *val, int *val2, long mask)
127 {
128 struct tcs3414_data *data = iio_priv(indio_dev);
129 int i, ret;
130
131 switch (mask) {
132 case IIO_CHAN_INFO_RAW:
133 ret = iio_device_claim_direct_mode(indio_dev);
134 if (ret)
135 return ret;
136 ret = tcs3414_req_data(data);
137 if (ret < 0) {
138 iio_device_release_direct_mode(indio_dev);
139 return ret;
140 }
141 ret = i2c_smbus_read_word_data(data->client, chan->address);
142 iio_device_release_direct_mode(indio_dev);
143 if (ret < 0)
144 return ret;
145 *val = ret;
146 return IIO_VAL_INT;
147 case IIO_CHAN_INFO_SCALE:
148 i = (data->gain & TCS3414_GAIN_MASK) >> TCS3414_GAIN_SHIFT;
149 *val = tcs3414_scales[i][0];
150 *val2 = tcs3414_scales[i][1];
151 return IIO_VAL_INT_PLUS_MICRO;
152 case IIO_CHAN_INFO_INT_TIME:
153 *val = 0;
154 *val2 = tcs3414_times[data->timing & TCS3414_INTEG_MASK] * 1000;
155 return IIO_VAL_INT_PLUS_MICRO;
156 }
157 return -EINVAL;
158 }
159
tcs3414_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)160 static int tcs3414_write_raw(struct iio_dev *indio_dev,
161 struct iio_chan_spec const *chan,
162 int val, int val2, long mask)
163 {
164 struct tcs3414_data *data = iio_priv(indio_dev);
165 int i;
166
167 switch (mask) {
168 case IIO_CHAN_INFO_SCALE:
169 for (i = 0; i < ARRAY_SIZE(tcs3414_scales); i++) {
170 if (val == tcs3414_scales[i][0] &&
171 val2 == tcs3414_scales[i][1]) {
172 data->gain &= ~TCS3414_GAIN_MASK;
173 data->gain |= i << TCS3414_GAIN_SHIFT;
174 return i2c_smbus_write_byte_data(
175 data->client, TCS3414_GAIN,
176 data->gain);
177 }
178 }
179 return -EINVAL;
180 case IIO_CHAN_INFO_INT_TIME:
181 if (val != 0)
182 return -EINVAL;
183 for (i = 0; i < ARRAY_SIZE(tcs3414_times); i++) {
184 if (val2 == tcs3414_times[i] * 1000) {
185 data->timing &= ~TCS3414_INTEG_MASK;
186 data->timing |= i;
187 return i2c_smbus_write_byte_data(
188 data->client, TCS3414_TIMING,
189 data->timing);
190 }
191 }
192 return -EINVAL;
193 default:
194 return -EINVAL;
195 }
196 }
197
tcs3414_trigger_handler(int irq,void * p)198 static irqreturn_t tcs3414_trigger_handler(int irq, void *p)
199 {
200 struct iio_poll_func *pf = p;
201 struct iio_dev *indio_dev = pf->indio_dev;
202 struct tcs3414_data *data = iio_priv(indio_dev);
203 int i, j = 0;
204
205 for_each_set_bit(i, indio_dev->active_scan_mask,
206 indio_dev->masklength) {
207 int ret = i2c_smbus_read_word_data(data->client,
208 TCS3414_DATA_GREEN + 2*i);
209 if (ret < 0)
210 goto done;
211
212 data->buffer[j++] = ret;
213 }
214
215 iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
216 iio_get_time_ns(indio_dev));
217
218 done:
219 iio_trigger_notify_done(indio_dev->trig);
220
221 return IRQ_HANDLED;
222 }
223
224 static IIO_CONST_ATTR(scale_available, "1 0.25 0.0625 0.015625");
225 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.012 0.1 0.4");
226
227 static struct attribute *tcs3414_attributes[] = {
228 &iio_const_attr_scale_available.dev_attr.attr,
229 &iio_const_attr_integration_time_available.dev_attr.attr,
230 NULL
231 };
232
233 static const struct attribute_group tcs3414_attribute_group = {
234 .attrs = tcs3414_attributes,
235 };
236
237 static const struct iio_info tcs3414_info = {
238 .read_raw = tcs3414_read_raw,
239 .write_raw = tcs3414_write_raw,
240 .attrs = &tcs3414_attribute_group,
241 };
242
tcs3414_buffer_postenable(struct iio_dev * indio_dev)243 static int tcs3414_buffer_postenable(struct iio_dev *indio_dev)
244 {
245 struct tcs3414_data *data = iio_priv(indio_dev);
246
247 data->control |= TCS3414_CONTROL_ADC_EN;
248 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
249 data->control);
250 }
251
tcs3414_buffer_predisable(struct iio_dev * indio_dev)252 static int tcs3414_buffer_predisable(struct iio_dev *indio_dev)
253 {
254 struct tcs3414_data *data = iio_priv(indio_dev);
255
256 data->control &= ~TCS3414_CONTROL_ADC_EN;
257 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
258 data->control);
259 }
260
261 static const struct iio_buffer_setup_ops tcs3414_buffer_setup_ops = {
262 .postenable = tcs3414_buffer_postenable,
263 .predisable = tcs3414_buffer_predisable,
264 };
265
tcs3414_probe(struct i2c_client * client,const struct i2c_device_id * id)266 static int tcs3414_probe(struct i2c_client *client,
267 const struct i2c_device_id *id)
268 {
269 struct tcs3414_data *data;
270 struct iio_dev *indio_dev;
271 int ret;
272
273 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
274 if (indio_dev == NULL)
275 return -ENOMEM;
276
277 data = iio_priv(indio_dev);
278 i2c_set_clientdata(client, indio_dev);
279 data->client = client;
280
281 indio_dev->info = &tcs3414_info;
282 indio_dev->name = TCS3414_DRV_NAME;
283 indio_dev->channels = tcs3414_channels;
284 indio_dev->num_channels = ARRAY_SIZE(tcs3414_channels);
285 indio_dev->modes = INDIO_DIRECT_MODE;
286
287 ret = i2c_smbus_read_byte_data(data->client, TCS3414_ID);
288 if (ret < 0)
289 return ret;
290
291 switch (ret & 0xf0) {
292 case 0x00:
293 dev_info(&client->dev, "TCS3404 found\n");
294 break;
295 case 0x10:
296 dev_info(&client->dev, "TCS3413/14/15/16 found\n");
297 break;
298 default:
299 return -ENODEV;
300 }
301
302 data->control = TCS3414_CONTROL_POWER;
303 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
304 data->control);
305 if (ret < 0)
306 return ret;
307
308 data->timing = TCS3414_INTEG_12MS; /* free running */
309 ret = i2c_smbus_write_byte_data(data->client, TCS3414_TIMING,
310 data->timing);
311 if (ret < 0)
312 return ret;
313
314 ret = i2c_smbus_read_byte_data(data->client, TCS3414_GAIN);
315 if (ret < 0)
316 return ret;
317 data->gain = ret;
318
319 ret = iio_triggered_buffer_setup(indio_dev, NULL,
320 tcs3414_trigger_handler, &tcs3414_buffer_setup_ops);
321 if (ret < 0)
322 return ret;
323
324 ret = iio_device_register(indio_dev);
325 if (ret < 0)
326 goto buffer_cleanup;
327
328 return 0;
329
330 buffer_cleanup:
331 iio_triggered_buffer_cleanup(indio_dev);
332 return ret;
333 }
334
tcs3414_powerdown(struct tcs3414_data * data)335 static int tcs3414_powerdown(struct tcs3414_data *data)
336 {
337 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
338 data->control & ~(TCS3414_CONTROL_POWER |
339 TCS3414_CONTROL_ADC_EN));
340 }
341
tcs3414_remove(struct i2c_client * client)342 static int tcs3414_remove(struct i2c_client *client)
343 {
344 struct iio_dev *indio_dev = i2c_get_clientdata(client);
345
346 iio_device_unregister(indio_dev);
347 iio_triggered_buffer_cleanup(indio_dev);
348 tcs3414_powerdown(iio_priv(indio_dev));
349
350 return 0;
351 }
352
353 #ifdef CONFIG_PM_SLEEP
tcs3414_suspend(struct device * dev)354 static int tcs3414_suspend(struct device *dev)
355 {
356 struct tcs3414_data *data = iio_priv(i2c_get_clientdata(
357 to_i2c_client(dev)));
358 return tcs3414_powerdown(data);
359 }
360
tcs3414_resume(struct device * dev)361 static int tcs3414_resume(struct device *dev)
362 {
363 struct tcs3414_data *data = iio_priv(i2c_get_clientdata(
364 to_i2c_client(dev)));
365 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
366 data->control);
367 }
368 #endif
369
370 static SIMPLE_DEV_PM_OPS(tcs3414_pm_ops, tcs3414_suspend, tcs3414_resume);
371
372 static const struct i2c_device_id tcs3414_id[] = {
373 { "tcs3414", 0 },
374 { }
375 };
376 MODULE_DEVICE_TABLE(i2c, tcs3414_id);
377
378 static struct i2c_driver tcs3414_driver = {
379 .driver = {
380 .name = TCS3414_DRV_NAME,
381 .pm = &tcs3414_pm_ops,
382 },
383 .probe = tcs3414_probe,
384 .remove = tcs3414_remove,
385 .id_table = tcs3414_id,
386 };
387 module_i2c_driver(tcs3414_driver);
388
389 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
390 MODULE_DESCRIPTION("TCS3414 digital color sensors driver");
391 MODULE_LICENSE("GPL");
392
