tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
51struct tcs3414_data {
52 struct i2c_client *client;
53 u8 control;
54 u8 gain;
55 u8 timing;
56};
57
58#define TCS3414_CHANNEL(_color, _si, _addr) { \
59 .type = IIO_INTENSITY, \
60 .modified = 1, \
61 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
62 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
63 BIT(IIO_CHAN_INFO_INT_TIME), \
64 .channel2 = IIO_MOD_LIGHT_##_color, \
65 .address = _addr, \
66 .scan_index = _si, \
67 .scan_type = { \
68 .sign = 'u', \
69 .realbits = 16, \
70 .storagebits = 16, \
71 .endianness = IIO_CPU, \
72 }, \
73}
74
75/* scale factors: 1/gain */
76static const int tcs3414_scales[][2] = {
77 {1, 0}, {0, 250000}, {0, 62500}, {0, 15625}
78};
79
80/* integration time in ms */
81static const int tcs3414_times[] = { 12, 100, 400 };
82
83static const struct iio_chan_spec tcs3414_channels[] = {
84 TCS3414_CHANNEL(GREEN, 0, TCS3414_DATA_GREEN),
85 TCS3414_CHANNEL(RED, 1, TCS3414_DATA_RED),
86 TCS3414_CHANNEL(BLUE, 2, TCS3414_DATA_BLUE),
87 TCS3414_CHANNEL(CLEAR, 3, TCS3414_DATA_CLEAR),
88 IIO_CHAN_SOFT_TIMESTAMP(4),
89};
90
91static int tcs3414_req_data(struct tcs3414_data *data)
92{
93 int tries = 25;
94 int ret;
95
96 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
97 data->control | TCS3414_CONTROL_ADC_EN);
98 if (ret < 0)
99 return ret;
100
101 while (tries--) {
102 ret = i2c_smbus_read_byte_data(data->client, TCS3414_CONTROL);
103 if (ret < 0)
104 return ret;
105 if (ret & TCS3414_CONTROL_ADC_VALID)
106 break;
107 msleep(20);
108 }
109
110 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
111 data->control);
112 if (ret < 0)
113 return ret;
114
115 if (tries < 0) {
116 dev_err(&data->client->dev, "data not ready\n");
117 return -EIO;
118 }
119
120 return 0;
121}
122
123static int tcs3414_read_raw(struct iio_dev *indio_dev,
124 struct iio_chan_spec const *chan,
125 int *val, int *val2, long mask)
126{
127 struct tcs3414_data *data = iio_priv(indio_dev);
128 int i, ret;
129
130 switch (mask) {
131 case IIO_CHAN_INFO_RAW:
132 if (!iio_device_claim_direct(indio_dev))
133 return -EBUSY;
134 ret = tcs3414_req_data(data);
135 if (ret < 0) {
136 iio_device_release_direct(indio_dev);
137 return ret;
138 }
139 ret = i2c_smbus_read_word_data(data->client, chan->address);
140 iio_device_release_direct(indio_dev);
141 if (ret < 0)
142 return ret;
143 *val = ret;
144 return IIO_VAL_INT;
145 case IIO_CHAN_INFO_SCALE:
146 i = (data->gain & TCS3414_GAIN_MASK) >> TCS3414_GAIN_SHIFT;
147 *val = tcs3414_scales[i][0];
148 *val2 = tcs3414_scales[i][1];
149 return IIO_VAL_INT_PLUS_MICRO;
150 case IIO_CHAN_INFO_INT_TIME:
151 *val = 0;
152 *val2 = tcs3414_times[data->timing & TCS3414_INTEG_MASK] * 1000;
153 return IIO_VAL_INT_PLUS_MICRO;
154 }
155 return -EINVAL;
156}
157
158static int tcs3414_write_raw(struct iio_dev *indio_dev,
159 struct iio_chan_spec const *chan,
160 int val, int val2, long mask)
161{
162 struct tcs3414_data *data = iio_priv(indio_dev);
163 int i;
164
165 switch (mask) {
166 case IIO_CHAN_INFO_SCALE:
167 for (i = 0; i < ARRAY_SIZE(tcs3414_scales); i++) {
168 if (val == tcs3414_scales[i][0] &&
169 val2 == tcs3414_scales[i][1]) {
170 data->gain &= ~TCS3414_GAIN_MASK;
171 data->gain |= i << TCS3414_GAIN_SHIFT;
172 return i2c_smbus_write_byte_data(
173 data->client, TCS3414_GAIN,
174 data->gain);
175 }
176 }
177 return -EINVAL;
178 case IIO_CHAN_INFO_INT_TIME:
179 if (val != 0)
180 return -EINVAL;
181 for (i = 0; i < ARRAY_SIZE(tcs3414_times); i++) {
182 if (val2 == tcs3414_times[i] * 1000) {
183 data->timing &= ~TCS3414_INTEG_MASK;
184 data->timing |= i;
185 return i2c_smbus_write_byte_data(
186 data->client, TCS3414_TIMING,
187 data->timing);
188 }
189 }
190 return -EINVAL;
191 default:
192 return -EINVAL;
193 }
194}
195
196static irqreturn_t tcs3414_trigger_handler(int irq, void *p)
197{
198 struct iio_poll_func *pf = p;
199 struct iio_dev *indio_dev = pf->indio_dev;
200 struct tcs3414_data *data = iio_priv(indio_dev);
201 int i, j = 0;
202 /* Ensure timestamp is naturally aligned */
203 struct {
204 u16 chans[4];
205 aligned_s64 timestamp;
206 } scan = { };
207
208
209 iio_for_each_active_channel(indio_dev, i) {
210 int ret = i2c_smbus_read_word_data(data->client,
211 TCS3414_DATA_GREEN + 2*i);
212 if (ret < 0)
213 goto done;
214
215 scan.chans[j++] = ret;
216 }
217
218 iio_push_to_buffers_with_ts(indio_dev, &scan, sizeof(scan),
219 iio_get_time_ns(indio_dev));
220
221done:
222 iio_trigger_notify_done(indio_dev->trig);
223
224 return IRQ_HANDLED;
225}
226
227static IIO_CONST_ATTR(scale_available, "1 0.25 0.0625 0.015625");
228static IIO_CONST_ATTR_INT_TIME_AVAIL("0.012 0.1 0.4");
229
230static struct attribute *tcs3414_attributes[] = {
231 &iio_const_attr_scale_available.dev_attr.attr,
232 &iio_const_attr_integration_time_available.dev_attr.attr,
233 NULL
234};
235
236static const struct attribute_group tcs3414_attribute_group = {
237 .attrs = tcs3414_attributes,
238};
239
240static const struct iio_info tcs3414_info = {
241 .read_raw = tcs3414_read_raw,
242 .write_raw = tcs3414_write_raw,
243 .attrs = &tcs3414_attribute_group,
244};
245
246static int tcs3414_buffer_postenable(struct iio_dev *indio_dev)
247{
248 struct tcs3414_data *data = iio_priv(indio_dev);
249
250 data->control |= TCS3414_CONTROL_ADC_EN;
251 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
252 data->control);
253}
254
255static int tcs3414_buffer_predisable(struct iio_dev *indio_dev)
256{
257 struct tcs3414_data *data = iio_priv(indio_dev);
258
259 data->control &= ~TCS3414_CONTROL_ADC_EN;
260 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
261 data->control);
262}
263
264static const struct iio_buffer_setup_ops tcs3414_buffer_setup_ops = {
265 .postenable = tcs3414_buffer_postenable,
266 .predisable = tcs3414_buffer_predisable,
267};
268
269static int tcs3414_powerdown(struct tcs3414_data *data)
270{
271 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
272 data->control & ~(TCS3414_CONTROL_POWER |
273 TCS3414_CONTROL_ADC_EN));
274}
275
276static void tcs3414_powerdown_cleanup(void *data)
277{
278 tcs3414_powerdown(data);
279}
280
281static int tcs3414_probe(struct i2c_client *client)
282{
283 struct tcs3414_data *data;
284 struct iio_dev *indio_dev;
285 int ret;
286
287 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
288 if (indio_dev == NULL)
289 return -ENOMEM;
290
291 data = iio_priv(indio_dev);
292 i2c_set_clientdata(client, indio_dev);
293 data->client = client;
294
295 indio_dev->info = &tcs3414_info;
296 indio_dev->name = TCS3414_DRV_NAME;
297 indio_dev->channels = tcs3414_channels;
298 indio_dev->num_channels = ARRAY_SIZE(tcs3414_channels);
299 indio_dev->modes = INDIO_DIRECT_MODE;
300
301 ret = i2c_smbus_read_byte_data(data->client, TCS3414_ID);
302 if (ret < 0)
303 return ret;
304
305 switch (ret & 0xf0) {
306 case 0x00:
307 dev_info(&client->dev, "TCS3404 found\n");
308 break;
309 case 0x10:
310 dev_info(&client->dev, "TCS3413/14/15/16 found\n");
311 break;
312 default:
313 return -ENODEV;
314 }
315
316 data->control = TCS3414_CONTROL_POWER;
317 ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
318 data->control);
319 if (ret < 0)
320 return ret;
321
322 ret = devm_add_action_or_reset(&client->dev, tcs3414_powerdown_cleanup,
323 data);
324 if (ret < 0)
325 return ret;
326
327 data->timing = TCS3414_INTEG_12MS; /* free running */
328 ret = i2c_smbus_write_byte_data(data->client, TCS3414_TIMING,
329 data->timing);
330 if (ret < 0)
331 return ret;
332
333 ret = i2c_smbus_read_byte_data(data->client, TCS3414_GAIN);
334 if (ret < 0)
335 return ret;
336 data->gain = ret;
337
338 ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
339 tcs3414_trigger_handler, &tcs3414_buffer_setup_ops);
340 if (ret < 0)
341 return ret;
342
343 return devm_iio_device_register(&client->dev, indio_dev);
344}
345
346static int tcs3414_suspend(struct device *dev)
347{
348 struct tcs3414_data *data = iio_priv(i2c_get_clientdata(
349 to_i2c_client(dev)));
350 return tcs3414_powerdown(data);
351}
352
353static int tcs3414_resume(struct device *dev)
354{
355 struct tcs3414_data *data = iio_priv(i2c_get_clientdata(
356 to_i2c_client(dev)));
357 return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
358 data->control);
359}
360
361static DEFINE_SIMPLE_DEV_PM_OPS(tcs3414_pm_ops, tcs3414_suspend,
362 tcs3414_resume);
363
364static const struct i2c_device_id tcs3414_id[] = {
365 { "tcs3414" },
366 { }
367};
368MODULE_DEVICE_TABLE(i2c, tcs3414_id);
369
370static struct i2c_driver tcs3414_driver = {
371 .driver = {
372 .name = TCS3414_DRV_NAME,
373 .pm = pm_sleep_ptr(&tcs3414_pm_ops),
374 },
375 .probe = tcs3414_probe,
376 .id_table = tcs3414_id,
377};
378module_i2c_driver(tcs3414_driver);
379
380MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
381MODULE_DESCRIPTION("TCS3414 digital color sensors driver");
382MODULE_LICENSE("GPL");