1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Support for AMS AS73211 JENCOLOR(R) Digital XYZ Sensor
4 *
5 * Author: Christian Eggers <ceggers@arri.de>
6 *
7 * Copyright (c) 2020 ARRI Lighting
8 *
9 * Color light sensor with 16-bit channels for x, y, z and temperature);
10 * 7-bit I2C slave address 0x74 .. 0x77.
11 *
12 * Datasheet: https://ams.com/documents/20143/36005/AS73211_DS000556_3-01.pdf
13 */
14
15#include <linux/bitfield.h>
16#include <linux/completion.h>
17#include <linux/delay.h>
18#include <linux/i2c.h>
19#include <linux/iio/buffer.h>
20#include <linux/iio/iio.h>
21#include <linux/iio/sysfs.h>
22#include <linux/iio/trigger_consumer.h>
23#include <linux/iio/triggered_buffer.h>
24#include <linux/module.h>
25#include <linux/mutex.h>
26#include <linux/pm.h>
27#include <linux/units.h>
28
29#define AS73211_DRV_NAME "as73211"
30
31/* AS73211 configuration registers */
32#define AS73211_REG_OSR    0x0
33#define AS73211_REG_AGEN   0x2
34#define AS73211_REG_CREG1  0x6
35#define AS73211_REG_CREG2  0x7
36#define AS73211_REG_CREG3  0x8
37
38/* AS73211 output register bank */
39#define AS73211_OUT_OSR_STATUS    0
40#define AS73211_OUT_TEMP          1
41#define AS73211_OUT_MRES1         2
42#define AS73211_OUT_MRES2         3
43#define AS73211_OUT_MRES3         4
44
45#define AS73211_OSR_SS            BIT(7)
46#define AS73211_OSR_PD            BIT(6)
47#define AS73211_OSR_SW_RES        BIT(3)
48#define AS73211_OSR_DOS_MASK      GENMASK(2, 0)
49#define AS73211_OSR_DOS_CONFIG    FIELD_PREP(AS73211_OSR_DOS_MASK, 0x2)
50#define AS73211_OSR_DOS_MEASURE   FIELD_PREP(AS73211_OSR_DOS_MASK, 0x3)
51
52#define AS73211_AGEN_DEVID_MASK   GENMASK(7, 4)
53#define AS73211_AGEN_DEVID(x)     FIELD_PREP(AS73211_AGEN_DEVID_MASK, (x))
54#define AS73211_AGEN_MUT_MASK     GENMASK(3, 0)
55#define AS73211_AGEN_MUT(x)       FIELD_PREP(AS73211_AGEN_MUT_MASK, (x))
56
57#define AS73211_CREG1_GAIN_MASK   GENMASK(7, 4)
58#define AS73211_CREG1_GAIN_1      11
59#define AS73211_CREG1_TIME_MASK   GENMASK(3, 0)
60
61#define AS73211_CREG3_CCLK_MASK   GENMASK(1, 0)
62
63#define AS73211_OSR_STATUS_OUTCONVOF  BIT(15)
64#define AS73211_OSR_STATUS_MRESOF     BIT(14)
65#define AS73211_OSR_STATUS_ADCOF      BIT(13)
66#define AS73211_OSR_STATUS_LDATA      BIT(12)
67#define AS73211_OSR_STATUS_NDATA      BIT(11)
68#define AS73211_OSR_STATUS_NOTREADY   BIT(10)
69
70#define AS73211_SAMPLE_FREQ_BASE      1024000
71
72#define AS73211_SAMPLE_TIME_NUM       15
73#define AS73211_SAMPLE_TIME_MAX_MS    BIT(AS73211_SAMPLE_TIME_NUM - 1)
74
75/* Available sample frequencies are 1.024MHz multiplied by powers of two. */
76static const int as73211_samp_freq_avail[] = {
77	AS73211_SAMPLE_FREQ_BASE * 1,
78	AS73211_SAMPLE_FREQ_BASE * 2,
79	AS73211_SAMPLE_FREQ_BASE * 4,
80	AS73211_SAMPLE_FREQ_BASE * 8,
81};
82
83static const int as73211_hardwaregain_avail[] = {
84	1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048,
85};
86
87/**
88 * struct as73211_data - Instance data for one AS73211
89 * @client: I2C client.
90 * @osr:    Cached Operational State Register.
91 * @creg1:  Cached Configuration Register 1.
92 * @creg2:  Cached Configuration Register 2.
93 * @creg3:  Cached Configuration Register 3.
94 * @mutex:  Keeps cached registers in sync with the device.
95 * @completion: Completion to wait for interrupt.
96 * @int_time_avail: Available integration times (depend on sampling frequency).
97 */
98struct as73211_data {
99	struct i2c_client *client;
100	u8 osr;
101	u8 creg1;
102	u8 creg2;
103	u8 creg3;
104	struct mutex mutex;
105	struct completion completion;
106	int int_time_avail[AS73211_SAMPLE_TIME_NUM * 2];
107};
108
109#define AS73211_COLOR_CHANNEL(_color, _si, _addr) { \
110	.type = IIO_INTENSITY, \
111	.modified = 1, \
112	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), \
113	.info_mask_shared_by_type = \
114		BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
115		BIT(IIO_CHAN_INFO_HARDWAREGAIN) | \
116		BIT(IIO_CHAN_INFO_INT_TIME), \
117	.info_mask_shared_by_type_available = \
118		BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
119		BIT(IIO_CHAN_INFO_HARDWAREGAIN) | \
120		BIT(IIO_CHAN_INFO_INT_TIME), \
121	.channel2 = IIO_MOD_##_color, \
122	.address = _addr, \
123	.scan_index = _si, \
124	.scan_type = { \
125		.sign = 'u', \
126		.realbits = 16, \
127		.storagebits = 16, \
128		.endianness = IIO_LE, \
129	}, \
130}
131
132#define AS73211_OFFSET_TEMP_INT    (-66)
133#define AS73211_OFFSET_TEMP_MICRO  900000
134#define AS73211_SCALE_TEMP_INT     0
135#define AS73211_SCALE_TEMP_MICRO   50000
136
137#define AS73211_SCALE_X 277071108  /* nW/m^2 */
138#define AS73211_SCALE_Y 298384270  /* nW/m^2 */
139#define AS73211_SCALE_Z 160241927  /* nW/m^2 */
140
141/* Channel order MUST match devices result register order */
142#define AS73211_SCAN_INDEX_TEMP 0
143#define AS73211_SCAN_INDEX_X    1
144#define AS73211_SCAN_INDEX_Y    2
145#define AS73211_SCAN_INDEX_Z    3
146#define AS73211_SCAN_INDEX_TS   4
147
148#define AS73211_SCAN_MASK_COLOR ( \
149	BIT(AS73211_SCAN_INDEX_X) |   \
150	BIT(AS73211_SCAN_INDEX_Y) |   \
151	BIT(AS73211_SCAN_INDEX_Z))
152
153#define AS73211_SCAN_MASK_ALL (    \
154	BIT(AS73211_SCAN_INDEX_TEMP) | \
155	AS73211_SCAN_MASK_COLOR)
156
157static const struct iio_chan_spec as73211_channels[] = {
158	{
159		.type = IIO_TEMP,
160		.info_mask_separate =
161			BIT(IIO_CHAN_INFO_RAW) |
162			BIT(IIO_CHAN_INFO_OFFSET) |
163			BIT(IIO_CHAN_INFO_SCALE),
164		.address = AS73211_OUT_TEMP,
165		.scan_index = AS73211_SCAN_INDEX_TEMP,
166		.scan_type = {
167			.sign = 'u',
168			.realbits = 16,
169			.storagebits = 16,
170			.endianness = IIO_LE,
171		}
172	},
173	AS73211_COLOR_CHANNEL(X, AS73211_SCAN_INDEX_X, AS73211_OUT_MRES1),
174	AS73211_COLOR_CHANNEL(Y, AS73211_SCAN_INDEX_Y, AS73211_OUT_MRES2),
175	AS73211_COLOR_CHANNEL(Z, AS73211_SCAN_INDEX_Z, AS73211_OUT_MRES3),
176	IIO_CHAN_SOFT_TIMESTAMP(AS73211_SCAN_INDEX_TS),
177};
178
179static unsigned int as73211_integration_time_1024cyc(struct as73211_data *data)
180{
181	/*
182	 * Return integration time in units of 1024 clock cycles. Integration time
183	 * in CREG1 is in powers of 2 (x 1024 cycles).
184	 */
185	return BIT(FIELD_GET(AS73211_CREG1_TIME_MASK, data->creg1));
186}
187
188static unsigned int as73211_integration_time_us(struct as73211_data *data,
189						 unsigned int integration_time_1024cyc)
190{
191	/*
192	 * f_samp is configured in CREG3 in powers of 2 (x 1.024 MHz)
193	 * t_cycl is configured in CREG1 in powers of 2 (x 1024 cycles)
194	 * t_int_us = 1 / (f_samp) * t_cycl * US_PER_SEC
195	 *          = 1 / (2^CREG3_CCLK * 1,024,000) * 2^CREG1_CYCLES * 1,024 * US_PER_SEC
196	 *          = 2^(-CREG3_CCLK) * 2^CREG1_CYCLES * 1,000
197	 * In order to get rid of negative exponents, we extend the "fraction"
198	 * by 2^3 (CREG3_CCLK,max = 3)
199	 * t_int_us = 2^(3-CREG3_CCLK) * 2^CREG1_CYCLES * 125
200	 */
201	return BIT(3 - FIELD_GET(AS73211_CREG3_CCLK_MASK, data->creg3)) *
202		integration_time_1024cyc * 125;
203}
204
205static void as73211_integration_time_calc_avail(struct as73211_data *data)
206{
207	int i;
208
209	for (i = 0; i < ARRAY_SIZE(data->int_time_avail) / 2; i++) {
210		unsigned int time_us = as73211_integration_time_us(data, BIT(i));
211
212		data->int_time_avail[i * 2 + 0] = time_us / USEC_PER_SEC;
213		data->int_time_avail[i * 2 + 1] = time_us % USEC_PER_SEC;
214	}
215}
216
217static unsigned int as73211_gain(struct as73211_data *data)
218{
219	/* gain can be calculated from CREG1 as 2^(11 - CREG1_GAIN) */
220	return BIT(AS73211_CREG1_GAIN_1 - FIELD_GET(AS73211_CREG1_GAIN_MASK, data->creg1));
221}
222
223/* must be called with as73211_data::mutex held. */
224static int as73211_req_data(struct as73211_data *data)
225{
226	unsigned int time_us = as73211_integration_time_us(data,
227							    as73211_integration_time_1024cyc(data));
228	struct device *dev = &data->client->dev;
229	union i2c_smbus_data smbus_data;
230	u16 osr_status;
231	int ret;
232
233	if (data->client->irq)
234		reinit_completion(&data->completion);
235
236	/*
237	 * During measurement, there should be no traffic on the i2c bus as the
238	 * electrical noise would disturb the measurement process.
239	 */
240	i2c_lock_bus(data->client->adapter, I2C_LOCK_SEGMENT);
241
242	data->osr &= ~AS73211_OSR_DOS_MASK;
243	data->osr |= AS73211_OSR_DOS_MEASURE | AS73211_OSR_SS;
244
245	smbus_data.byte = data->osr;
246	ret = __i2c_smbus_xfer(data->client->adapter, data->client->addr,
247			data->client->flags, I2C_SMBUS_WRITE,
248			AS73211_REG_OSR, I2C_SMBUS_BYTE_DATA, &smbus_data);
249	if (ret < 0) {
250		i2c_unlock_bus(data->client->adapter, I2C_LOCK_SEGMENT);
251		return ret;
252	}
253
254	/*
255	 * Reset AS73211_OSR_SS (is self clearing) in order to avoid unintentional
256	 * triggering of further measurements later.
257	 */
258	data->osr &= ~AS73211_OSR_SS;
259
260	/*
261	 * Add 33% extra margin for the timeout. fclk,min = fclk,typ - 27%.
262	 */
263	time_us += time_us / 3;
264	if (data->client->irq) {
265		ret = wait_for_completion_timeout(&data->completion, usecs_to_jiffies(time_us));
266		if (!ret) {
267			dev_err(dev, "timeout waiting for READY IRQ\n");
268			i2c_unlock_bus(data->client->adapter, I2C_LOCK_SEGMENT);
269			return -ETIMEDOUT;
270		}
271	} else {
272		/* Wait integration time */
273		usleep_range(time_us, 2 * time_us);
274	}
275
276	i2c_unlock_bus(data->client->adapter, I2C_LOCK_SEGMENT);
277
278	ret = i2c_smbus_read_word_data(data->client, AS73211_OUT_OSR_STATUS);
279	if (ret < 0)
280		return ret;
281
282	osr_status = ret;
283	if (osr_status != (AS73211_OSR_DOS_MEASURE | AS73211_OSR_STATUS_NDATA)) {
284		if (osr_status & AS73211_OSR_SS) {
285			dev_err(dev, "%s() Measurement has not stopped\n", __func__);
286			return -ETIME;
287		}
288		if (osr_status & AS73211_OSR_STATUS_NOTREADY) {
289			dev_err(dev, "%s() Data is not ready\n", __func__);
290			return -ENODATA;
291		}
292		if (!(osr_status & AS73211_OSR_STATUS_NDATA)) {
293			dev_err(dev, "%s() No new data available\n", __func__);
294			return -ENODATA;
295		}
296		if (osr_status & AS73211_OSR_STATUS_LDATA) {
297			dev_err(dev, "%s() Result buffer overrun\n", __func__);
298			return -ENOBUFS;
299		}
300		if (osr_status & AS73211_OSR_STATUS_ADCOF) {
301			dev_err(dev, "%s() ADC overflow\n", __func__);
302			return -EOVERFLOW;
303		}
304		if (osr_status & AS73211_OSR_STATUS_MRESOF) {
305			dev_err(dev, "%s() Measurement result overflow\n", __func__);
306			return -EOVERFLOW;
307		}
308		if (osr_status & AS73211_OSR_STATUS_OUTCONVOF) {
309			dev_err(dev, "%s() Timer overflow\n", __func__);
310			return -EOVERFLOW;
311		}
312		dev_err(dev, "%s() Unexpected status value\n", __func__);
313		return -EIO;
314	}
315
316	return 0;
317}
318
319static int as73211_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
320			     int *val, int *val2, long mask)
321{
322	struct as73211_data *data = iio_priv(indio_dev);
323
324	switch (mask) {
325	case IIO_CHAN_INFO_RAW: {
326		int ret;
327
328		ret = iio_device_claim_direct_mode(indio_dev);
329		if (ret < 0)
330			return ret;
331
332		ret = as73211_req_data(data);
333		if (ret < 0) {
334			iio_device_release_direct_mode(indio_dev);
335			return ret;
336		}
337
338		ret = i2c_smbus_read_word_data(data->client, chan->address);
339		iio_device_release_direct_mode(indio_dev);
340		if (ret < 0)
341			return ret;
342
343		*val = ret;
344		return IIO_VAL_INT;
345	}
346	case IIO_CHAN_INFO_OFFSET:
347		*val = AS73211_OFFSET_TEMP_INT;
348		*val2 = AS73211_OFFSET_TEMP_MICRO;
349		return IIO_VAL_INT_PLUS_MICRO;
350
351	case IIO_CHAN_INFO_SCALE:
352		switch (chan->type) {
353		case IIO_TEMP:
354			*val = AS73211_SCALE_TEMP_INT;
355			*val2 = AS73211_SCALE_TEMP_MICRO;
356			return IIO_VAL_INT_PLUS_MICRO;
357
358		case IIO_INTENSITY: {
359			unsigned int scale;
360
361			switch (chan->channel2) {
362			case IIO_MOD_X:
363				scale = AS73211_SCALE_X;
364				break;
365			case IIO_MOD_Y:
366				scale = AS73211_SCALE_Y;
367				break;
368			case IIO_MOD_Z:
369				scale = AS73211_SCALE_Z;
370				break;
371			default:
372				return -EINVAL;
373			}
374			scale /= as73211_gain(data);
375			scale /= as73211_integration_time_1024cyc(data);
376			*val = scale;
377			return IIO_VAL_INT;
378
379		default:
380			return -EINVAL;
381		}}
382
383	case IIO_CHAN_INFO_SAMP_FREQ:
384		/* f_samp is configured in CREG3 in powers of 2 (x 1.024 MHz) */
385		*val = BIT(FIELD_GET(AS73211_CREG3_CCLK_MASK, data->creg3)) *
386			AS73211_SAMPLE_FREQ_BASE;
387		return IIO_VAL_INT;
388
389	case IIO_CHAN_INFO_HARDWAREGAIN:
390		*val = as73211_gain(data);
391		return IIO_VAL_INT;
392
393	case IIO_CHAN_INFO_INT_TIME: {
394		unsigned int time_us;
395
396		mutex_lock(&data->mutex);
397		time_us = as73211_integration_time_us(data, as73211_integration_time_1024cyc(data));
398		mutex_unlock(&data->mutex);
399		*val = time_us / USEC_PER_SEC;
400		*val2 = time_us % USEC_PER_SEC;
401		return IIO_VAL_INT_PLUS_MICRO;
402
403	default:
404		return -EINVAL;
405	}}
406}
407
408static int as73211_read_avail(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
409			       const int **vals, int *type, int *length, long mask)
410{
411	struct as73211_data *data = iio_priv(indio_dev);
412
413	switch (mask) {
414	case IIO_CHAN_INFO_SAMP_FREQ:
415		*length = ARRAY_SIZE(as73211_samp_freq_avail);
416		*vals = as73211_samp_freq_avail;
417		*type = IIO_VAL_INT;
418		return IIO_AVAIL_LIST;
419
420	case IIO_CHAN_INFO_HARDWAREGAIN:
421		*length = ARRAY_SIZE(as73211_hardwaregain_avail);
422		*vals = as73211_hardwaregain_avail;
423		*type = IIO_VAL_INT;
424		return IIO_AVAIL_LIST;
425
426	case IIO_CHAN_INFO_INT_TIME:
427		*length = ARRAY_SIZE(data->int_time_avail);
428		*vals = data->int_time_avail;
429		*type = IIO_VAL_INT_PLUS_MICRO;
430		return IIO_AVAIL_LIST;
431
432	default:
433		return -EINVAL;
434	}
435}
436
437static int _as73211_write_raw(struct iio_dev *indio_dev,
438			       struct iio_chan_spec const *chan __always_unused,
439			       int val, int val2, long mask)
440{
441	struct as73211_data *data = iio_priv(indio_dev);
442	int ret;
443
444	switch (mask) {
445	case IIO_CHAN_INFO_SAMP_FREQ: {
446		int reg_bits, freq_kHz = val / HZ_PER_KHZ;  /* 1024, 2048, ... */
447
448		/* val must be 1024 * 2^x */
449		if (val < 0 || (freq_kHz * HZ_PER_KHZ) != val ||
450				!is_power_of_2(freq_kHz) || val2)
451			return -EINVAL;
452
453		/* f_samp is configured in CREG3 in powers of 2 (x 1.024 MHz (=2^10)) */
454		reg_bits = ilog2(freq_kHz) - 10;
455		if (!FIELD_FIT(AS73211_CREG3_CCLK_MASK, reg_bits))
456			return -EINVAL;
457
458		data->creg3 &= ~AS73211_CREG3_CCLK_MASK;
459		data->creg3 |= FIELD_PREP(AS73211_CREG3_CCLK_MASK, reg_bits);
460		as73211_integration_time_calc_avail(data);
461
462		ret = i2c_smbus_write_byte_data(data->client, AS73211_REG_CREG3, data->creg3);
463		if (ret < 0)
464			return ret;
465
466		return 0;
467	}
468	case IIO_CHAN_INFO_HARDWAREGAIN: {
469		unsigned int reg_bits;
470
471		if (val < 0 || !is_power_of_2(val) || val2)
472			return -EINVAL;
473
474		/* gain can be calculated from CREG1 as 2^(11 - CREG1_GAIN) */
475		reg_bits = AS73211_CREG1_GAIN_1 - ilog2(val);
476		if (!FIELD_FIT(AS73211_CREG1_GAIN_MASK, reg_bits))
477			return -EINVAL;
478
479		data->creg1 &= ~AS73211_CREG1_GAIN_MASK;
480		data->creg1 |= FIELD_PREP(AS73211_CREG1_GAIN_MASK, reg_bits);
481
482		ret = i2c_smbus_write_byte_data(data->client, AS73211_REG_CREG1, data->creg1);
483		if (ret < 0)
484			return ret;
485
486		return 0;
487	}
488	case IIO_CHAN_INFO_INT_TIME: {
489		int val_us = val * USEC_PER_SEC + val2;
490		int time_ms;
491		int reg_bits;
492
493		/* f_samp is configured in CREG3 in powers of 2 (x 1.024 MHz) */
494		int f_samp_1_024mhz = BIT(FIELD_GET(AS73211_CREG3_CCLK_MASK, data->creg3));
495
496		/*
497		 * time_ms = time_us * US_PER_MS * f_samp_1_024mhz / MHZ_PER_HZ
498		 *         = time_us * f_samp_1_024mhz / 1000
499		 */
500		time_ms = (val_us * f_samp_1_024mhz) / 1000;  /* 1 ms, 2 ms, ... (power of two) */
501		if (time_ms < 0 || !is_power_of_2(time_ms) || time_ms > AS73211_SAMPLE_TIME_MAX_MS)
502			return -EINVAL;
503
504		reg_bits = ilog2(time_ms);
505		if (!FIELD_FIT(AS73211_CREG1_TIME_MASK, reg_bits))
506			return -EINVAL;  /* not possible due to previous tests */
507
508		data->creg1 &= ~AS73211_CREG1_TIME_MASK;
509		data->creg1 |= FIELD_PREP(AS73211_CREG1_TIME_MASK, reg_bits);
510
511		ret = i2c_smbus_write_byte_data(data->client, AS73211_REG_CREG1, data->creg1);
512		if (ret < 0)
513			return ret;
514
515		return 0;
516
517	default:
518		return -EINVAL;
519	}}
520}
521
522static int as73211_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
523			      int val, int val2, long mask)
524{
525	struct as73211_data *data = iio_priv(indio_dev);
526	int ret;
527
528	mutex_lock(&data->mutex);
529
530	ret = iio_device_claim_direct_mode(indio_dev);
531	if (ret < 0)
532		goto error_unlock;
533
534	/* Need to switch to config mode ... */
535	if ((data->osr & AS73211_OSR_DOS_MASK) != AS73211_OSR_DOS_CONFIG) {
536		data->osr &= ~AS73211_OSR_DOS_MASK;
537		data->osr |= AS73211_OSR_DOS_CONFIG;
538
539		ret = i2c_smbus_write_byte_data(data->client, AS73211_REG_OSR, data->osr);
540		if (ret < 0)
541			goto error_release;
542	}
543
544	ret = _as73211_write_raw(indio_dev, chan, val, val2, mask);
545
546error_release:
547	iio_device_release_direct_mode(indio_dev);
548error_unlock:
549	mutex_unlock(&data->mutex);
550	return ret;
551}
552
553static irqreturn_t as73211_ready_handler(int irq __always_unused, void *priv)
554{
555	struct as73211_data *data = iio_priv(priv);
556
557	complete(&data->completion);
558
559	return IRQ_HANDLED;
560}
561
562static irqreturn_t as73211_trigger_handler(int irq __always_unused, void *p)
563{
564	struct iio_poll_func *pf = p;
565	struct iio_dev *indio_dev = pf->indio_dev;
566	struct as73211_data *data = iio_priv(indio_dev);
567	struct {
568		__le16 chan[4];
569		s64 ts __aligned(8);
570	} scan;
571	int data_result, ret;
572
573	mutex_lock(&data->mutex);
574
575	data_result = as73211_req_data(data);
576	if (data_result < 0 && data_result != -EOVERFLOW)
577		goto done;  /* don't push any data for errors other than EOVERFLOW */
578
579	if (*indio_dev->active_scan_mask == AS73211_SCAN_MASK_ALL) {
580		/* Optimization for reading all (color + temperature) channels */
581		u8 addr = as73211_channels[0].address;
582		struct i2c_msg msgs[] = {
583			{
584				.addr = data->client->addr,
585				.flags = 0,
586				.len = 1,
587				.buf = &addr,
588			},
589			{
590				.addr = data->client->addr,
591				.flags = I2C_M_RD,
592				.len = sizeof(scan.chan),
593				.buf = (u8 *)&scan.chan,
594			},
595		};
596
597		ret = i2c_transfer(data->client->adapter, msgs, ARRAY_SIZE(msgs));
598		if (ret < 0)
599			goto done;
600	} else {
601		/* Optimization for reading only color channels */
602
603		/* AS73211 starts reading at address 2 */
604		ret = i2c_master_recv(data->client,
605				(char *)&scan.chan[1], 3 * sizeof(scan.chan[1]));
606		if (ret < 0)
607			goto done;
608	}
609
610	if (data_result) {
611		/*
612		 * Saturate all channels (in case of overflows). Temperature channel
613		 * is not affected by overflows.
614		 */
615		scan.chan[1] = cpu_to_le16(U16_MAX);
616		scan.chan[2] = cpu_to_le16(U16_MAX);
617		scan.chan[3] = cpu_to_le16(U16_MAX);
618	}
619
620	iio_push_to_buffers_with_timestamp(indio_dev, &scan, iio_get_time_ns(indio_dev));
621
622done:
623	mutex_unlock(&data->mutex);
624	iio_trigger_notify_done(indio_dev->trig);
625
626	return IRQ_HANDLED;
627}
628
629static const struct iio_info as73211_info = {
630	.read_raw = as73211_read_raw,
631	.read_avail = as73211_read_avail,
632	.write_raw = as73211_write_raw,
633};
634
635static int as73211_power(struct iio_dev *indio_dev, bool state)
636{
637	struct as73211_data *data = iio_priv(indio_dev);
638	int ret;
639
640	mutex_lock(&data->mutex);
641
642	if (state)
643		data->osr &= ~AS73211_OSR_PD;
644	else
645		data->osr |= AS73211_OSR_PD;
646
647	ret = i2c_smbus_write_byte_data(data->client, AS73211_REG_OSR, data->osr);
648
649	mutex_unlock(&data->mutex);
650
651	if (ret < 0)
652		return ret;
653
654	return 0;
655}
656
657static void as73211_power_disable(void *data)
658{
659	struct iio_dev *indio_dev = data;
660
661	as73211_power(indio_dev, false);
662}
663
664static int as73211_probe(struct i2c_client *client)
665{
666	struct device *dev = &client->dev;
667	struct as73211_data *data;
668	struct iio_dev *indio_dev;
669	int ret;
670
671	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
672	if (!indio_dev)
673		return -ENOMEM;
674
675	data = iio_priv(indio_dev);
676	i2c_set_clientdata(client, indio_dev);
677	data->client = client;
678
679	mutex_init(&data->mutex);
680	init_completion(&data->completion);
681
682	indio_dev->info = &as73211_info;
683	indio_dev->name = AS73211_DRV_NAME;
684	indio_dev->channels = as73211_channels;
685	indio_dev->num_channels = ARRAY_SIZE(as73211_channels);
686	indio_dev->modes = INDIO_DIRECT_MODE;
687
688	ret = i2c_smbus_read_byte_data(data->client, AS73211_REG_OSR);
689	if (ret < 0)
690		return ret;
691	data->osr = ret;
692
693	/* reset device */
694	data->osr |= AS73211_OSR_SW_RES;
695	ret = i2c_smbus_write_byte_data(data->client, AS73211_REG_OSR, data->osr);
696	if (ret < 0)
697		return ret;
698
699	ret = i2c_smbus_read_byte_data(data->client, AS73211_REG_OSR);
700	if (ret < 0)
701		return ret;
702	data->osr = ret;
703
704	/*
705	 * Reading AGEN is only possible after reset (AGEN is not available if
706	 * device is in measurement mode).
707	 */
708	ret = i2c_smbus_read_byte_data(data->client, AS73211_REG_AGEN);
709	if (ret < 0)
710		return ret;
711
712	/* At the time of writing this driver, only DEVID 2 and MUT 1 are known. */
713	if ((ret & AS73211_AGEN_DEVID_MASK) != AS73211_AGEN_DEVID(2) ||
714	    (ret & AS73211_AGEN_MUT_MASK) != AS73211_AGEN_MUT(1))
715		return -ENODEV;
716
717	ret = i2c_smbus_read_byte_data(data->client, AS73211_REG_CREG1);
718	if (ret < 0)
719		return ret;
720	data->creg1 = ret;
721
722	ret = i2c_smbus_read_byte_data(data->client, AS73211_REG_CREG2);
723	if (ret < 0)
724		return ret;
725	data->creg2 = ret;
726
727	ret = i2c_smbus_read_byte_data(data->client, AS73211_REG_CREG3);
728	if (ret < 0)
729		return ret;
730	data->creg3 = ret;
731	as73211_integration_time_calc_avail(data);
732
733	ret = as73211_power(indio_dev, true);
734	if (ret < 0)
735		return ret;
736
737	ret = devm_add_action_or_reset(dev, as73211_power_disable, indio_dev);
738	if (ret)
739		return ret;
740
741	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, as73211_trigger_handler, NULL);
742	if (ret)
743		return ret;
744
745	if (client->irq) {
746		ret = devm_request_threaded_irq(&client->dev, client->irq,
747				NULL,
748				as73211_ready_handler,
749				IRQF_ONESHOT,
750				client->name, indio_dev);
751		if (ret)
752			return ret;
753	}
754
755	return devm_iio_device_register(dev, indio_dev);
756}
757
758static int as73211_suspend(struct device *dev)
759{
760	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
761
762	return as73211_power(indio_dev, false);
763}
764
765static int as73211_resume(struct device *dev)
766{
767	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
768
769	return as73211_power(indio_dev, true);
770}
771
772static DEFINE_SIMPLE_DEV_PM_OPS(as73211_pm_ops, as73211_suspend,
773				as73211_resume);
774
775static const struct of_device_id as73211_of_match[] = {
776	{ .compatible = "ams,as73211" },
777	{ }
778};
779MODULE_DEVICE_TABLE(of, as73211_of_match);
780
781static const struct i2c_device_id as73211_id[] = {
782	{ "as73211", 0 },
783	{ }
784};
785MODULE_DEVICE_TABLE(i2c, as73211_id);
786
787static struct i2c_driver as73211_driver = {
788	.driver = {
789		.name           = AS73211_DRV_NAME,
790		.of_match_table = as73211_of_match,
791		.pm             = pm_sleep_ptr(&as73211_pm_ops),
792	},
793	.probe      = as73211_probe,
794	.id_table   = as73211_id,
795};
796module_i2c_driver(as73211_driver);
797
798MODULE_AUTHOR("Christian Eggers <ceggers@arri.de>");
799MODULE_DESCRIPTION("AS73211 XYZ True Color Sensor driver");
800MODULE_LICENSE("GPL");
801