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