xref: /openbmc/linux/drivers/iio/light/as73211.c (revision 2208f39c)
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. */
77 static 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 
84 static 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  */
99 struct 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 
158 static 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 
180 static 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 
189 static 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 
206 static 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 
218 static 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. */
225 static 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 
320 static 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 
409 static 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 
438 static 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 
523 static 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 
547 error_release:
548 	iio_device_release_direct_mode(indio_dev);
549 error_unlock:
550 	mutex_unlock(&data->mutex);
551 	return ret;
552 }
553 
554 static 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 
563 static 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 
623 done:
624 	mutex_unlock(&data->mutex);
625 	iio_trigger_notify_done(indio_dev->trig);
626 
627 	return IRQ_HANDLED;
628 }
629 
630 static 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 
636 static 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 
658 static void as73211_power_disable(void *data)
659 {
660 	struct iio_dev *indio_dev = data;
661 
662 	as73211_power(indio_dev, false);
663 }
664 
665 static 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 
759 static 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 
766 static 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 
773 static SIMPLE_DEV_PM_OPS(as73211_pm_ops, as73211_suspend, as73211_resume);
774 
775 static const struct of_device_id as73211_of_match[] = {
776 	{ .compatible = "ams,as73211" },
777 	{ }
778 };
779 MODULE_DEVICE_TABLE(of, as73211_of_match);
780 
781 static const struct i2c_device_id as73211_id[] = {
782 	{ "as73211", 0 },
783 	{ }
784 };
785 MODULE_DEVICE_TABLE(i2c, as73211_id);
786 
787 static 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 };
796 module_i2c_driver(as73211_driver);
797 
798 MODULE_AUTHOR("Christian Eggers <ceggers@arri.de>");
799 MODULE_DESCRIPTION("AS73211 XYZ True Color Sensor driver");
800 MODULE_LICENSE("GPL");
801