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 /* Ensure timestamp is naturally aligned */
57 struct {
58 u16 chans[4];
59 s64 timestamp __aligned(8);
60 } scan;
61 };
62
63 #define TCS3414_CHANNEL(_color, _si, _addr) { \
64 .type = IIO_INTENSITY, \
65 .modified = 1, \
66 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
67 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
68 BIT(IIO_CHAN_INFO_INT_TIME), \
69 .channel2 = IIO_MOD_LIGHT_##_color, \
70 .address = _addr, \
71 .scan_index = _si, \
72 .scan_type = { \
73 .sign = 'u', \
74 .realbits = 16, \
75 .storagebits = 16, \
76 .endianness = IIO_CPU, \
77 }, \
78 }
79
80 /* scale factors: 1/gain */
81 static const int tcs3414_scales[][2] = {
82 {1, 0}, {0, 250000}, {0, 62500}, {0, 15625}
83 };
84
85 /* integration time in ms */
86 static const int tcs3414_times[] = { 12, 100, 400 };
87
88 static const struct iio_chan_spec tcs3414_channels[] = {
89 TCS3414_CHANNEL(GREEN, 0, TCS3414_DATA_GREEN),
90 TCS3414_CHANNEL(RED, 1, TCS3414_DATA_RED),
91 TCS3414_CHANNEL(BLUE, 2, TCS3414_DATA_BLUE),
92 TCS3414_CHANNEL(CLEAR, 3, TCS3414_DATA_CLEAR),
93 IIO_CHAN_SOFT_TIMESTAMP(4),
94 };
95
tcs3414_req_data(struct tcs3414_data * data)96 static int tcs3414_req_data(struct tcs3414_data *data)
97 {
98 int tries = 25;
99 int ret;
100
101 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
102 data->control | TCS3414_CONTROL_ADC_EN);
103 if (ret < 0)
104 return ret;
105
106 while (tries--) {
107 ret = i2c_smbus_read_byte_data(data->client, TCS3414_CONTROL);
108 if (ret < 0)
109 return ret;
110 if (ret & TCS3414_CONTROL_ADC_VALID)
111 break;
112 msleep(20);
113 }
114
115 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
116 data->control);
117 if (ret < 0)
118 return ret;
119
120 if (tries < 0) {
121 dev_err(&data->client->dev, "data not ready\n");
122 return -EIO;
123 }
124
125 return 0;
126 }
127
tcs3414_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)128 static int tcs3414_read_raw(struct iio_dev *indio_dev,
129 struct iio_chan_spec const *chan,
130 int *val, int *val2, long mask)
131 {
132 struct tcs3414_data *data = iio_priv(indio_dev);
133 int i, ret;
134
135 switch (mask) {
136 case IIO_CHAN_INFO_RAW:
137 ret = iio_device_claim_direct_mode(indio_dev);
138 if (ret)
139 return ret;
140 ret = tcs3414_req_data(data);
141 if (ret < 0) {
142 iio_device_release_direct_mode(indio_dev);
143 return ret;
144 }
145 ret = i2c_smbus_read_word_data(data->client, chan->address);
146 iio_device_release_direct_mode(indio_dev);
147 if (ret < 0)
148 return ret;
149 *val = ret;
150 return IIO_VAL_INT;
151 case IIO_CHAN_INFO_SCALE:
152 i = (data->gain & TCS3414_GAIN_MASK) >> TCS3414_GAIN_SHIFT;
153 *val = tcs3414_scales[i][0];
154 *val2 = tcs3414_scales[i][1];
155 return IIO_VAL_INT_PLUS_MICRO;
156 case IIO_CHAN_INFO_INT_TIME:
157 *val = 0;
158 *val2 = tcs3414_times[data->timing & TCS3414_INTEG_MASK] * 1000;
159 return IIO_VAL_INT_PLUS_MICRO;
160 }
161 return -EINVAL;
162 }
163
tcs3414_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)164 static int tcs3414_write_raw(struct iio_dev *indio_dev,
165 struct iio_chan_spec const *chan,
166 int val, int val2, long mask)
167 {
168 struct tcs3414_data *data = iio_priv(indio_dev);
169 int i;
170
171 switch (mask) {
172 case IIO_CHAN_INFO_SCALE:
173 for (i = 0; i < ARRAY_SIZE(tcs3414_scales); i++) {
174 if (val == tcs3414_scales[i][0] &&
175 val2 == tcs3414_scales[i][1]) {
176 data->gain &= ~TCS3414_GAIN_MASK;
177 data->gain |= i << TCS3414_GAIN_SHIFT;
178 return i2c_smbus_write_byte_data(
179 data->client, TCS3414_GAIN,
180 data->gain);
181 }
182 }
183 return -EINVAL;
184 case IIO_CHAN_INFO_INT_TIME:
185 if (val != 0)
186 return -EINVAL;
187 for (i = 0; i < ARRAY_SIZE(tcs3414_times); i++) {
188 if (val2 == tcs3414_times[i] * 1000) {
189 data->timing &= ~TCS3414_INTEG_MASK;
190 data->timing |= i;
191 return i2c_smbus_write_byte_data(
192 data->client, TCS3414_TIMING,
193 data->timing);
194 }
195 }
196 return -EINVAL;
197 default:
198 return -EINVAL;
199 }
200 }
201
tcs3414_trigger_handler(int irq,void * p)202 static irqreturn_t tcs3414_trigger_handler(int irq, void *p)
203 {
204 struct iio_poll_func *pf = p;
205 struct iio_dev *indio_dev = pf->indio_dev;
206 struct tcs3414_data *data = iio_priv(indio_dev);
207 int i, j = 0;
208
209 for_each_set_bit(i, indio_dev->active_scan_mask,
210 indio_dev->masklength) {
211 int ret = i2c_smbus_read_word_data(data->client,
212 TCS3414_DATA_GREEN + 2*i);
213 if (ret < 0)
214 goto done;
215
216 data->scan.chans[j++] = ret;
217 }
218
219 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
220 iio_get_time_ns(indio_dev));
221
222 done:
223 iio_trigger_notify_done(indio_dev->trig);
224
225 return IRQ_HANDLED;
226 }
227
228 static IIO_CONST_ATTR(scale_available, "1 0.25 0.0625 0.015625");
229 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.012 0.1 0.4");
230
231 static struct attribute *tcs3414_attributes[] = {
232 &iio_const_attr_scale_available.dev_attr.attr,
233 &iio_const_attr_integration_time_available.dev_attr.attr,
234 NULL
235 };
236
237 static const struct attribute_group tcs3414_attribute_group = {
238 .attrs = tcs3414_attributes,
239 };
240
241 static const struct iio_info tcs3414_info = {
242 .read_raw = tcs3414_read_raw,
243 .write_raw = tcs3414_write_raw,
244 .attrs = &tcs3414_attribute_group,
245 };
246
tcs3414_buffer_postenable(struct iio_dev * indio_dev)247 static int tcs3414_buffer_postenable(struct iio_dev *indio_dev)
248 {
249 struct tcs3414_data *data = iio_priv(indio_dev);
250
251 data->control |= TCS3414_CONTROL_ADC_EN;
252 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
253 data->control);
254 }
255
tcs3414_buffer_predisable(struct iio_dev * indio_dev)256 static int tcs3414_buffer_predisable(struct iio_dev *indio_dev)
257 {
258 struct tcs3414_data *data = iio_priv(indio_dev);
259
260 data->control &= ~TCS3414_CONTROL_ADC_EN;
261 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
262 data->control);
263 }
264
265 static const struct iio_buffer_setup_ops tcs3414_buffer_setup_ops = {
266 .postenable = tcs3414_buffer_postenable,
267 .predisable = tcs3414_buffer_predisable,
268 };
269
tcs3414_powerdown(struct tcs3414_data * data)270 static int tcs3414_powerdown(struct tcs3414_data *data)
271 {
272 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
273 data->control & ~(TCS3414_CONTROL_POWER |
274 TCS3414_CONTROL_ADC_EN));
275 }
276
tcs3414_powerdown_cleanup(void * data)277 static void tcs3414_powerdown_cleanup(void *data)
278 {
279 tcs3414_powerdown(data);
280 }
281
tcs3414_probe(struct i2c_client * client)282 static int tcs3414_probe(struct i2c_client *client)
283 {
284 struct tcs3414_data *data;
285 struct iio_dev *indio_dev;
286 int ret;
287
288 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
289 if (indio_dev == NULL)
290 return -ENOMEM;
291
292 data = iio_priv(indio_dev);
293 i2c_set_clientdata(client, indio_dev);
294 data->client = client;
295
296 indio_dev->info = &tcs3414_info;
297 indio_dev->name = TCS3414_DRV_NAME;
298 indio_dev->channels = tcs3414_channels;
299 indio_dev->num_channels = ARRAY_SIZE(tcs3414_channels);
300 indio_dev->modes = INDIO_DIRECT_MODE;
301
302 ret = i2c_smbus_read_byte_data(data->client, TCS3414_ID);
303 if (ret < 0)
304 return ret;
305
306 switch (ret & 0xf0) {
307 case 0x00:
308 dev_info(&client->dev, "TCS3404 found\n");
309 break;
310 case 0x10:
311 dev_info(&client->dev, "TCS3413/14/15/16 found\n");
312 break;
313 default:
314 return -ENODEV;
315 }
316
317 data->control = TCS3414_CONTROL_POWER;
318 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
319 data->control);
320 if (ret < 0)
321 return ret;
322
323 ret = devm_add_action_or_reset(&client->dev, tcs3414_powerdown_cleanup,
324 data);
325 if (ret < 0)
326 return ret;
327
328 data->timing = TCS3414_INTEG_12MS; /* free running */
329 ret = i2c_smbus_write_byte_data(data->client, TCS3414_TIMING,
330 data->timing);
331 if (ret < 0)
332 return ret;
333
334 ret = i2c_smbus_read_byte_data(data->client, TCS3414_GAIN);
335 if (ret < 0)
336 return ret;
337 data->gain = ret;
338
339 ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
340 tcs3414_trigger_handler, &tcs3414_buffer_setup_ops);
341 if (ret < 0)
342 return ret;
343
344 return devm_iio_device_register(&client->dev, indio_dev);
345 }
346
tcs3414_suspend(struct device * dev)347 static int tcs3414_suspend(struct device *dev)
348 {
349 struct tcs3414_data *data = iio_priv(i2c_get_clientdata(
350 to_i2c_client(dev)));
351 return tcs3414_powerdown(data);
352 }
353
tcs3414_resume(struct device * dev)354 static int tcs3414_resume(struct device *dev)
355 {
356 struct tcs3414_data *data = iio_priv(i2c_get_clientdata(
357 to_i2c_client(dev)));
358 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
359 data->control);
360 }
361
362 static DEFINE_SIMPLE_DEV_PM_OPS(tcs3414_pm_ops, tcs3414_suspend,
363 tcs3414_resume);
364
365 static const struct i2c_device_id tcs3414_id[] = {
366 { "tcs3414", 0 },
367 { }
368 };
369 MODULE_DEVICE_TABLE(i2c, tcs3414_id);
370
371 static struct i2c_driver tcs3414_driver = {
372 .driver = {
373 .name = TCS3414_DRV_NAME,
374 .pm = pm_sleep_ptr(&tcs3414_pm_ops),
375 },
376 .probe = tcs3414_probe,
377 .id_table = tcs3414_id,
378 };
379 module_i2c_driver(tcs3414_driver);
380
381 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
382 MODULE_DESCRIPTION("TCS3414 digital color sensors driver");
383 MODULE_LICENSE("GPL");
384