summaryrefslogtreecommitdiff
path: root/drivers/iio/light/tcs3414.c
blob: 5100732fbaf0a1255c89e17e622ada20601a5c0e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
// SPDX-License-Identifier: GPL-2.0-only
/*
 * tcs3414.c - Support for TAOS TCS3414 digital color sensor
 *
 * Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
 *
 * Digital color sensor with 16-bit channels for red, green, blue, clear);
 * 7-bit I2C slave address 0x39 (TCS3414) or 0x29, 0x49, 0x59 (TCS3413,
 * TCS3415, TCS3416, resp.)
 *
 * TODO: sync, interrupt support, thresholds, prescaler
 */

#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/pm.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/buffer.h>
#include <linux/iio/triggered_buffer.h>

#define TCS3414_DRV_NAME "tcs3414"

#define TCS3414_COMMAND BIT(7)
#define TCS3414_COMMAND_WORD (TCS3414_COMMAND | BIT(5))

#define TCS3414_CONTROL (TCS3414_COMMAND | 0x00)
#define TCS3414_TIMING (TCS3414_COMMAND | 0x01)
#define TCS3414_ID (TCS3414_COMMAND | 0x04)
#define TCS3414_GAIN (TCS3414_COMMAND | 0x07)
#define TCS3414_DATA_GREEN (TCS3414_COMMAND_WORD | 0x10)
#define TCS3414_DATA_RED (TCS3414_COMMAND_WORD | 0x12)
#define TCS3414_DATA_BLUE (TCS3414_COMMAND_WORD | 0x14)
#define TCS3414_DATA_CLEAR (TCS3414_COMMAND_WORD | 0x16)

#define TCS3414_CONTROL_ADC_VALID BIT(4)
#define TCS3414_CONTROL_ADC_EN BIT(1)
#define TCS3414_CONTROL_POWER BIT(0)

#define TCS3414_INTEG_MASK GENMASK(1, 0)
#define TCS3414_INTEG_12MS 0x0
#define TCS3414_INTEG_100MS 0x1
#define TCS3414_INTEG_400MS 0x2

#define TCS3414_GAIN_MASK GENMASK(5, 4)
#define TCS3414_GAIN_SHIFT 4

struct tcs3414_data {
	struct i2c_client *client;
	u8 control;
	u8 gain;
	u8 timing;
	/* Ensure timestamp is naturally aligned */
	struct {
		u16 chans[4];
		s64 timestamp __aligned(8);
	} scan;
};

#define TCS3414_CHANNEL(_color, _si, _addr) { \
	.type = IIO_INTENSITY, \
	.modified = 1, \
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
		BIT(IIO_CHAN_INFO_INT_TIME), \
	.channel2 = IIO_MOD_LIGHT_##_color, \
	.address = _addr, \
	.scan_index = _si, \
	.scan_type = { \
		.sign = 'u', \
		.realbits = 16, \
		.storagebits = 16, \
		.endianness = IIO_CPU, \
	}, \
}

/* scale factors: 1/gain */
static const int tcs3414_scales[][2] = {
	{1, 0}, {0, 250000}, {0, 62500}, {0, 15625}
};

/* integration time in ms */
static const int tcs3414_times[] = { 12, 100, 400 };

static const struct iio_chan_spec tcs3414_channels[] = {
	TCS3414_CHANNEL(GREEN, 0, TCS3414_DATA_GREEN),
	TCS3414_CHANNEL(RED, 1, TCS3414_DATA_RED),
	TCS3414_CHANNEL(BLUE, 2, TCS3414_DATA_BLUE),
	TCS3414_CHANNEL(CLEAR, 3, TCS3414_DATA_CLEAR),
	IIO_CHAN_SOFT_TIMESTAMP(4),
};

static int tcs3414_req_data(struct tcs3414_data *data)
{
	int tries = 25;
	int ret;

	ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
		data->control | TCS3414_CONTROL_ADC_EN);
	if (ret < 0)
		return ret;

	while (tries--) {
		ret = i2c_smbus_read_byte_data(data->client, TCS3414_CONTROL);
		if (ret < 0)
			return ret;
		if (ret & TCS3414_CONTROL_ADC_VALID)
			break;
		msleep(20);
	}

	ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
		data->control);
	if (ret < 0)
		return ret;

	if (tries < 0) {
		dev_err(&data->client->dev, "data not ready\n");
		return -EIO;
	}

	return 0;
}

static int tcs3414_read_raw(struct iio_dev *indio_dev,
			   struct iio_chan_spec const *chan,
			   int *val, int *val2, long mask)
{
	struct tcs3414_data *data = iio_priv(indio_dev);
	int i, ret;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		ret = iio_device_claim_direct_mode(indio_dev);
		if (ret)
			return ret;
		ret = tcs3414_req_data(data);
		if (ret < 0) {
			iio_device_release_direct_mode(indio_dev);
			return ret;
		}
		ret = i2c_smbus_read_word_data(data->client, chan->address);
		iio_device_release_direct_mode(indio_dev);
		if (ret < 0)
			return ret;
		*val = ret;
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_SCALE:
		i = (data->gain & TCS3414_GAIN_MASK) >> TCS3414_GAIN_SHIFT;
		*val = tcs3414_scales[i][0];
		*val2 = tcs3414_scales[i][1];
		return IIO_VAL_INT_PLUS_MICRO;
	case IIO_CHAN_INFO_INT_TIME:
		*val = 0;
		*val2 = tcs3414_times[data->timing & TCS3414_INTEG_MASK] * 1000;
		return IIO_VAL_INT_PLUS_MICRO;
	}
	return -EINVAL;
}

static int tcs3414_write_raw(struct iio_dev *indio_dev,
			       struct iio_chan_spec const *chan,
			       int val, int val2, long mask)
{
	struct tcs3414_data *data = iio_priv(indio_dev);
	int i;

	switch (mask) {
	case IIO_CHAN_INFO_SCALE:
		for (i = 0; i < ARRAY_SIZE(tcs3414_scales); i++) {
			if (val == tcs3414_scales[i][0] &&
				val2 == tcs3414_scales[i][1]) {
				data->gain &= ~TCS3414_GAIN_MASK;
				data->gain |= i << TCS3414_GAIN_SHIFT;
				return i2c_smbus_write_byte_data(
					data->client, TCS3414_GAIN,
					data->gain);
			}
		}
		return -EINVAL;
	case IIO_CHAN_INFO_INT_TIME:
		if (val != 0)
			return -EINVAL;
		for (i = 0; i < ARRAY_SIZE(tcs3414_times); i++) {
			if (val2 == tcs3414_times[i] * 1000) {
				data->timing &= ~TCS3414_INTEG_MASK;
				data->timing |= i;
				return i2c_smbus_write_byte_data(
					data->client, TCS3414_TIMING,
					data->timing);
			}
		}
		return -EINVAL;
	default:
		return -EINVAL;
	}
}

static irqreturn_t tcs3414_trigger_handler(int irq, void *p)
{
	struct iio_poll_func *pf = p;
	struct iio_dev *indio_dev = pf->indio_dev;
	struct tcs3414_data *data = iio_priv(indio_dev);
	int i, j = 0;

	for_each_set_bit(i, indio_dev->active_scan_mask,
		indio_dev->masklength) {
		int ret = i2c_smbus_read_word_data(data->client,
			TCS3414_DATA_GREEN + 2*i);
		if (ret < 0)
			goto done;

		data->scan.chans[j++] = ret;
	}

	iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
		iio_get_time_ns(indio_dev));

done:
	iio_trigger_notify_done(indio_dev->trig);

	return IRQ_HANDLED;
}

static IIO_CONST_ATTR(scale_available, "1 0.25 0.0625 0.015625");
static IIO_CONST_ATTR_INT_TIME_AVAIL("0.012 0.1 0.4");

static struct attribute *tcs3414_attributes[] = {
	&iio_const_attr_scale_available.dev_attr.attr,
	&iio_const_attr_integration_time_available.dev_attr.attr,
	NULL
};

static const struct attribute_group tcs3414_attribute_group = {
	.attrs = tcs3414_attributes,
};

static const struct iio_info tcs3414_info = {
	.read_raw = tcs3414_read_raw,
	.write_raw = tcs3414_write_raw,
	.attrs = &tcs3414_attribute_group,
};

static int tcs3414_buffer_postenable(struct iio_dev *indio_dev)
{
	struct tcs3414_data *data = iio_priv(indio_dev);

	data->control |= TCS3414_CONTROL_ADC_EN;
	return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
		data->control);
}

static int tcs3414_buffer_predisable(struct iio_dev *indio_dev)
{
	struct tcs3414_data *data = iio_priv(indio_dev);

	data->control &= ~TCS3414_CONTROL_ADC_EN;
	return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
		data->control);
}

static const struct iio_buffer_setup_ops tcs3414_buffer_setup_ops = {
	.postenable = tcs3414_buffer_postenable,
	.predisable = tcs3414_buffer_predisable,
};

static int tcs3414_powerdown(struct tcs3414_data *data)
{
	return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
		data->control & ~(TCS3414_CONTROL_POWER |
		TCS3414_CONTROL_ADC_EN));
}

static void tcs3414_powerdown_cleanup(void *data)
{
	tcs3414_powerdown(data);
}

static int tcs3414_probe(struct i2c_client *client)
{
	struct tcs3414_data *data;
	struct iio_dev *indio_dev;
	int ret;

	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	if (indio_dev == NULL)
		return -ENOMEM;

	data = iio_priv(indio_dev);
	i2c_set_clientdata(client, indio_dev);
	data->client = client;

	indio_dev->info = &tcs3414_info;
	indio_dev->name = TCS3414_DRV_NAME;
	indio_dev->channels = tcs3414_channels;
	indio_dev->num_channels = ARRAY_SIZE(tcs3414_channels);
	indio_dev->modes = INDIO_DIRECT_MODE;

	ret = i2c_smbus_read_byte_data(data->client, TCS3414_ID);
	if (ret < 0)
		return ret;

	switch (ret & 0xf0) {
	case 0x00:
		dev_info(&client->dev, "TCS3404 found\n");
		break;
	case 0x10:
		dev_info(&client->dev, "TCS3413/14/15/16 found\n");
		break;
	default:
		return -ENODEV;
	}

	data->control = TCS3414_CONTROL_POWER;
	ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
		data->control);
	if (ret < 0)
		return ret;

	ret = devm_add_action_or_reset(&client->dev, tcs3414_powerdown_cleanup,
				       data);
	if (ret < 0)
		return ret;

	data->timing = TCS3414_INTEG_12MS; /* free running */
	ret = i2c_smbus_write_byte_data(data->client, TCS3414_TIMING,
		data->timing);
	if (ret < 0)
		return ret;

	ret = i2c_smbus_read_byte_data(data->client, TCS3414_GAIN);
	if (ret < 0)
		return ret;
	data->gain = ret;

	ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
		tcs3414_trigger_handler, &tcs3414_buffer_setup_ops);
	if (ret < 0)
		return ret;

	return devm_iio_device_register(&client->dev, indio_dev);
}

static int tcs3414_suspend(struct device *dev)
{
	struct tcs3414_data *data = iio_priv(i2c_get_clientdata(
		to_i2c_client(dev)));
	return tcs3414_powerdown(data);
}

static int tcs3414_resume(struct device *dev)
{
	struct tcs3414_data *data = iio_priv(i2c_get_clientdata(
		to_i2c_client(dev)));
	return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
		data->control);
}

static DEFINE_SIMPLE_DEV_PM_OPS(tcs3414_pm_ops, tcs3414_suspend,
				tcs3414_resume);

static const struct i2c_device_id tcs3414_id[] = {
	{ "tcs3414", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, tcs3414_id);

static struct i2c_driver tcs3414_driver = {
	.driver = {
		.name	= TCS3414_DRV_NAME,
		.pm	= pm_sleep_ptr(&tcs3414_pm_ops),
	},
	.probe_new	= tcs3414_probe,
	.id_table	= tcs3414_id,
};
module_i2c_driver(tcs3414_driver);

MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_DESCRIPTION("TCS3414 digital color sensors driver");
MODULE_LICENSE("GPL");