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si1133.c

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linux-6.19.14/drivers/iio/light/si1133.c C
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * si1133.c - Support for Silabs SI1133 combined ambient
   4 * light and UV index sensors
   5 *
   6 * Copyright 2018 Maxime Roussin-Belanger <maxime.roussinbelanger@gmail.com>
   7 */
   8
   9#include <linux/delay.h>
  10#include <linux/i2c.h>
  11#include <linux/interrupt.h>
  12#include <linux/module.h>
  13#include <linux/regmap.h>
  14
  15#include <linux/iio/iio.h>
  16#include <linux/iio/sysfs.h>
  17
  18#include <linux/util_macros.h>
  19
  20#include <linux/unaligned.h>
  21
  22#define SI1133_REG_PART_ID		0x00
  23#define SI1133_REG_REV_ID		0x01
  24#define SI1133_REG_MFR_ID		0x02
  25#define SI1133_REG_INFO0		0x03
  26#define SI1133_REG_INFO1		0x04
  27
  28#define SI1133_PART_ID			0x33
  29
  30#define SI1133_REG_HOSTIN0		0x0A
  31#define SI1133_REG_COMMAND		0x0B
  32#define SI1133_REG_IRQ_ENABLE		0x0F
  33#define SI1133_REG_RESPONSE1		0x10
  34#define SI1133_REG_RESPONSE0		0x11
  35#define SI1133_REG_IRQ_STATUS		0x12
  36#define SI1133_REG_MEAS_RATE		0x1A
  37
  38#define SI1133_IRQ_CHANNEL_ENABLE	0xF
  39
  40#define SI1133_CMD_RESET_CTR		0x00
  41#define SI1133_CMD_RESET_SW		0x01
  42#define SI1133_CMD_FORCE		0x11
  43#define SI1133_CMD_START_AUTONOMOUS	0x13
  44#define SI1133_CMD_PARAM_SET		0x80
  45#define SI1133_CMD_PARAM_QUERY		0x40
  46#define SI1133_CMD_PARAM_MASK		0x3F
  47
  48#define SI1133_CMD_ERR_MASK		BIT(4)
  49#define SI1133_CMD_SEQ_MASK		0xF
  50#define SI1133_MAX_CMD_CTR		0xF
  51
  52#define SI1133_PARAM_REG_CHAN_LIST	0x01
  53#define SI1133_PARAM_REG_ADCCONFIG(x)	((x) * 4) + 2
  54#define SI1133_PARAM_REG_ADCSENS(x)	((x) * 4) + 3
  55#define SI1133_PARAM_REG_ADCPOST(x)	((x) * 4) + 4
  56
  57#define SI1133_ADCMUX_MASK 0x1F
  58
  59#define SI1133_ADCCONFIG_DECIM_RATE(x)	(x) << 5
  60
  61#define SI1133_ADCSENS_SCALE_MASK 0x70
  62#define SI1133_ADCSENS_SCALE_SHIFT 4
  63#define SI1133_ADCSENS_HSIG_MASK BIT(7)
  64#define SI1133_ADCSENS_HSIG_SHIFT 7
  65#define SI1133_ADCSENS_HW_GAIN_MASK 0xF
  66#define SI1133_ADCSENS_NB_MEAS(x)	fls(x) << SI1133_ADCSENS_SCALE_SHIFT
  67
  68#define SI1133_ADCPOST_24BIT_EN BIT(6)
  69#define SI1133_ADCPOST_POSTSHIFT_BITQTY(x) (x & GENMASK(2, 0)) << 3
  70
  71#define SI1133_PARAM_ADCMUX_SMALL_IR	0x0
  72#define SI1133_PARAM_ADCMUX_MED_IR	0x1
  73#define SI1133_PARAM_ADCMUX_LARGE_IR	0x2
  74#define SI1133_PARAM_ADCMUX_WHITE	0xB
  75#define SI1133_PARAM_ADCMUX_LARGE_WHITE	0xD
  76#define SI1133_PARAM_ADCMUX_UV		0x18
  77#define SI1133_PARAM_ADCMUX_UV_DEEP	0x19
  78
  79#define SI1133_ERR_INVALID_CMD		0x0
  80#define SI1133_ERR_INVALID_LOCATION_CMD 0x1
  81#define SI1133_ERR_SATURATION_ADC_OR_OVERFLOW_ACCUMULATION 0x2
  82#define SI1133_ERR_OUTPUT_BUFFER_OVERFLOW 0x3
  83
  84#define SI1133_COMPLETION_TIMEOUT_MS	500
  85
  86#define SI1133_CMD_MINSLEEP_US_LOW	5000
  87#define SI1133_CMD_MINSLEEP_US_HIGH	7500
  88#define SI1133_CMD_TIMEOUT_MS		25
  89#define SI1133_CMD_LUX_TIMEOUT_MS	5000
  90#define SI1133_CMD_TIMEOUT_US		SI1133_CMD_TIMEOUT_MS * 1000
  91
  92#define SI1133_REG_HOSTOUT(x)		(x) + 0x13
  93
  94#define SI1133_MEASUREMENT_FREQUENCY 1250
  95
  96#define SI1133_X_ORDER_MASK            0x0070
  97#define SI1133_Y_ORDER_MASK            0x0007
  98#define si1133_get_x_order(m)          ((m) & SI1133_X_ORDER_MASK) >> 4
  99#define si1133_get_y_order(m)          ((m) & SI1133_Y_ORDER_MASK)
 100
 101#define SI1133_LUX_ADC_MASK		0xE
 102#define SI1133_ADC_THRESHOLD		16000
 103#define SI1133_INPUT_FRACTION_HIGH	7
 104#define SI1133_INPUT_FRACTION_LOW	15
 105#define SI1133_LUX_OUTPUT_FRACTION	12
 106#define SI1133_LUX_BUFFER_SIZE		9
 107#define SI1133_MEASURE_BUFFER_SIZE	3
 108
 109static const int si1133_scale_available[] = {
 110	1, 2, 4, 8, 16, 32, 64, 128};
 111
 112static IIO_CONST_ATTR(scale_available, "1 2 4 8 16 32 64 128");
 113
 114static IIO_CONST_ATTR_INT_TIME_AVAIL("0.0244 0.0488 0.0975 0.195 0.390 0.780 "
 115				     "1.560 3.120 6.24 12.48 25.0 50.0");
 116
 117/* A.K.A. HW_GAIN in datasheet */
 118enum si1133_int_time {
 119	    _24_4_us = 0,
 120	    _48_8_us = 1,
 121	    _97_5_us = 2,
 122	   _195_0_us = 3,
 123	   _390_0_us = 4,
 124	   _780_0_us = 5,
 125	 _1_560_0_us = 6,
 126	 _3_120_0_us = 7,
 127	 _6_240_0_us = 8,
 128	_12_480_0_us = 9,
 129	_25_ms = 10,
 130	_50_ms = 11,
 131};
 132
 133/* Integration time in milliseconds, nanoseconds */
 134static const int si1133_int_time_table[][2] = {
 135	[_24_4_us] = {0, 24400},
 136	[_48_8_us] = {0, 48800},
 137	[_97_5_us] = {0, 97500},
 138	[_195_0_us] = {0, 195000},
 139	[_390_0_us] = {0, 390000},
 140	[_780_0_us] = {0, 780000},
 141	[_1_560_0_us] = {1, 560000},
 142	[_3_120_0_us] = {3, 120000},
 143	[_6_240_0_us] = {6, 240000},
 144	[_12_480_0_us] = {12, 480000},
 145	[_25_ms] = {25, 000000},
 146	[_50_ms] = {50, 000000},
 147};
 148
 149static const struct regmap_range si1133_reg_ranges[] = {
 150	regmap_reg_range(0x00, 0x02),
 151	regmap_reg_range(0x0A, 0x0B),
 152	regmap_reg_range(0x0F, 0x0F),
 153	regmap_reg_range(0x10, 0x12),
 154	regmap_reg_range(0x13, 0x2C),
 155};
 156
 157static const struct regmap_range si1133_reg_ro_ranges[] = {
 158	regmap_reg_range(0x00, 0x02),
 159	regmap_reg_range(0x10, 0x2C),
 160};
 161
 162static const struct regmap_range si1133_precious_ranges[] = {
 163	regmap_reg_range(0x12, 0x12),
 164};
 165
 166static const struct regmap_access_table si1133_write_ranges_table = {
 167	.yes_ranges	= si1133_reg_ranges,
 168	.n_yes_ranges	= ARRAY_SIZE(si1133_reg_ranges),
 169	.no_ranges	= si1133_reg_ro_ranges,
 170	.n_no_ranges	= ARRAY_SIZE(si1133_reg_ro_ranges),
 171};
 172
 173static const struct regmap_access_table si1133_read_ranges_table = {
 174	.yes_ranges	= si1133_reg_ranges,
 175	.n_yes_ranges	= ARRAY_SIZE(si1133_reg_ranges),
 176};
 177
 178static const struct regmap_access_table si1133_precious_table = {
 179	.yes_ranges	= si1133_precious_ranges,
 180	.n_yes_ranges	= ARRAY_SIZE(si1133_precious_ranges),
 181};
 182
 183static const struct regmap_config si1133_regmap_config = {
 184	.reg_bits = 8,
 185	.val_bits = 8,
 186
 187	.max_register = 0x2C,
 188
 189	.wr_table = &si1133_write_ranges_table,
 190	.rd_table = &si1133_read_ranges_table,
 191
 192	.precious_table = &si1133_precious_table,
 193};
 194
 195struct si1133_data {
 196	struct regmap *regmap;
 197	struct i2c_client *client;
 198
 199	/* Lock protecting one command at a time can be processed */
 200	struct mutex mutex;
 201
 202	int rsp_seq;
 203	u8 scan_mask;
 204	u8 adc_sens[6];
 205	u8 adc_config[6];
 206
 207	struct completion completion;
 208};
 209
 210struct si1133_coeff {
 211	s16 info;
 212	u16 mag;
 213};
 214
 215struct si1133_lux_coeff {
 216	struct si1133_coeff coeff_high[4];
 217	struct si1133_coeff coeff_low[9];
 218};
 219
 220static const struct si1133_lux_coeff lux_coeff = {
 221	{
 222		{  0,   209},
 223		{ 1665,  93},
 224		{ 2064,  65},
 225		{-2671, 234}
 226	},
 227	{
 228		{    0,     0},
 229		{ 1921, 29053},
 230		{-1022, 36363},
 231		{ 2320, 20789},
 232		{ -367, 57909},
 233		{-1774, 38240},
 234		{ -608, 46775},
 235		{-1503, 51831},
 236		{-1886, 58928}
 237	}
 238};
 239
 240static int si1133_calculate_polynomial_inner(s32 input, u8 fraction, u16 mag,
 241					     s8 shift)
 242{
 243	return ((input << fraction) / mag) << shift;
 244}
 245
 246static int si1133_calculate_output(s32 x, s32 y, u8 x_order, u8 y_order,
 247				   u8 input_fraction, s8 sign,
 248				   const struct si1133_coeff *coeffs)
 249{
 250	s8 shift;
 251	int x1 = 1;
 252	int x2 = 1;
 253	int y1 = 1;
 254	int y2 = 1;
 255
 256	shift = ((u16)coeffs->info & 0xFF00) >> 8;
 257	shift ^= 0xFF;
 258	shift += 1;
 259	shift = -shift;
 260
 261	if (x_order > 0) {
 262		x1 = si1133_calculate_polynomial_inner(x, input_fraction,
 263						       coeffs->mag, shift);
 264		if (x_order > 1)
 265			x2 = x1;
 266	}
 267
 268	if (y_order > 0) {
 269		y1 = si1133_calculate_polynomial_inner(y, input_fraction,
 270						       coeffs->mag, shift);
 271		if (y_order > 1)
 272			y2 = y1;
 273	}
 274
 275	return sign * x1 * x2 * y1 * y2;
 276}
 277
 278/*
 279 * The algorithm is from:
 280 * https://siliconlabs.github.io/Gecko_SDK_Doc/efm32zg/html/si1133_8c_source.html#l00716
 281 */
 282static int si1133_calc_polynomial(s32 x, s32 y, u8 input_fraction, u8 num_coeff,
 283				  const struct si1133_coeff *coeffs)
 284{
 285	u8 x_order, y_order;
 286	u8 counter;
 287	s8 sign;
 288	int output = 0;
 289
 290	for (counter = 0; counter < num_coeff; counter++) {
 291		if (coeffs->info < 0)
 292			sign = -1;
 293		else
 294			sign = 1;
 295
 296		x_order = si1133_get_x_order(coeffs->info);
 297		y_order = si1133_get_y_order(coeffs->info);
 298
 299		if ((x_order == 0) && (y_order == 0))
 300			output +=
 301			       sign * coeffs->mag << SI1133_LUX_OUTPUT_FRACTION;
 302		else
 303			output += si1133_calculate_output(x, y, x_order,
 304							  y_order,
 305							  input_fraction, sign,
 306							  coeffs);
 307		coeffs++;
 308	}
 309
 310	return abs(output);
 311}
 312
 313static int si1133_cmd_reset_sw(struct si1133_data *data)
 314{
 315	struct device *dev = &data->client->dev;
 316	unsigned int resp;
 317	unsigned long timeout;
 318	int err;
 319
 320	err = regmap_write(data->regmap, SI1133_REG_COMMAND,
 321			   SI1133_CMD_RESET_SW);
 322	if (err)
 323		return err;
 324
 325	timeout = jiffies + msecs_to_jiffies(SI1133_CMD_TIMEOUT_MS);
 326	while (true) {
 327		err = regmap_read(data->regmap, SI1133_REG_RESPONSE0, &resp);
 328		if (err == -ENXIO) {
 329			usleep_range(SI1133_CMD_MINSLEEP_US_LOW,
 330				     SI1133_CMD_MINSLEEP_US_HIGH);
 331			continue;
 332		}
 333
 334		if ((resp & SI1133_MAX_CMD_CTR) == SI1133_MAX_CMD_CTR)
 335			break;
 336
 337		if (time_after(jiffies, timeout)) {
 338			dev_warn(dev, "Timeout on reset ctr resp: %d\n", resp);
 339			return -ETIMEDOUT;
 340		}
 341	}
 342
 343	if (!err)
 344		data->rsp_seq = SI1133_MAX_CMD_CTR;
 345
 346	return err;
 347}
 348
 349static int si1133_parse_response_err(struct device *dev, u32 resp, u8 cmd)
 350{
 351	resp &= 0xF;
 352
 353	switch (resp) {
 354	case SI1133_ERR_OUTPUT_BUFFER_OVERFLOW:
 355		dev_warn(dev, "Output buffer overflow: 0x%02x\n", cmd);
 356		return -EOVERFLOW;
 357	case SI1133_ERR_SATURATION_ADC_OR_OVERFLOW_ACCUMULATION:
 358		dev_warn(dev, "Saturation of the ADC or overflow of accumulation: 0x%02x\n",
 359			 cmd);
 360		return -EOVERFLOW;
 361	case SI1133_ERR_INVALID_LOCATION_CMD:
 362		dev_warn(dev,
 363			 "Parameter access to an invalid location: 0x%02x\n",
 364			 cmd);
 365		return -EINVAL;
 366	case SI1133_ERR_INVALID_CMD:
 367		dev_warn(dev, "Invalid command 0x%02x\n", cmd);
 368		return -EINVAL;
 369	default:
 370		dev_warn(dev, "Unknown error 0x%02x\n", cmd);
 371		return -EINVAL;
 372	}
 373}
 374
 375static int si1133_cmd_reset_counter(struct si1133_data *data)
 376{
 377	int err = regmap_write(data->regmap, SI1133_REG_COMMAND,
 378			       SI1133_CMD_RESET_CTR);
 379	if (err)
 380		return err;
 381
 382	data->rsp_seq = 0;
 383
 384	return 0;
 385}
 386
 387static int si1133_command(struct si1133_data *data, u8 cmd)
 388{
 389	struct device *dev = &data->client->dev;
 390	u32 resp;
 391	int err;
 392	int expected_seq;
 393
 394	mutex_lock(&data->mutex);
 395
 396	expected_seq = (data->rsp_seq + 1) & SI1133_MAX_CMD_CTR;
 397
 398	if (cmd == SI1133_CMD_FORCE)
 399		reinit_completion(&data->completion);
 400
 401	err = regmap_write(data->regmap, SI1133_REG_COMMAND, cmd);
 402	if (err) {
 403		dev_warn(dev, "Failed to write command 0x%02x, ret=%d\n", cmd,
 404			 err);
 405		goto out;
 406	}
 407
 408	if (cmd == SI1133_CMD_FORCE) {
 409		/* wait for irq */
 410		if (!wait_for_completion_timeout(&data->completion,
 411			msecs_to_jiffies(SI1133_COMPLETION_TIMEOUT_MS))) {
 412			err = -ETIMEDOUT;
 413			goto out;
 414		}
 415		err = regmap_read(data->regmap, SI1133_REG_RESPONSE0, &resp);
 416		if (err)
 417			goto out;
 418	} else {
 419		err = regmap_read_poll_timeout(data->regmap,
 420					       SI1133_REG_RESPONSE0, resp,
 421					       (resp & SI1133_CMD_SEQ_MASK) ==
 422					       expected_seq ||
 423					       (resp & SI1133_CMD_ERR_MASK),
 424					       SI1133_CMD_MINSLEEP_US_LOW,
 425					       SI1133_CMD_TIMEOUT_MS * 1000);
 426		if (err) {
 427			dev_warn(dev,
 428				 "Failed to read command 0x%02x, ret=%d\n",
 429				 cmd, err);
 430			goto out;
 431		}
 432	}
 433
 434	if (resp & SI1133_CMD_ERR_MASK) {
 435		err = si1133_parse_response_err(dev, resp, cmd);
 436		si1133_cmd_reset_counter(data);
 437	} else {
 438		data->rsp_seq = expected_seq;
 439	}
 440
 441out:
 442	mutex_unlock(&data->mutex);
 443
 444	return err;
 445}
 446
 447static int si1133_param_set(struct si1133_data *data, u8 param, u32 value)
 448{
 449	int err = regmap_write(data->regmap, SI1133_REG_HOSTIN0, value);
 450
 451	if (err)
 452		return err;
 453
 454	return si1133_command(data, SI1133_CMD_PARAM_SET |
 455			      (param & SI1133_CMD_PARAM_MASK));
 456}
 457
 458static int si1133_param_query(struct si1133_data *data, u8 param, u32 *result)
 459{
 460	int err = si1133_command(data, SI1133_CMD_PARAM_QUERY |
 461				 (param & SI1133_CMD_PARAM_MASK));
 462	if (err)
 463		return err;
 464
 465	return regmap_read(data->regmap, SI1133_REG_RESPONSE1, result);
 466}
 467
 468#define SI1133_CHANNEL(_ch, _type) \
 469	.type = _type, \
 470	.channel = _ch, \
 471	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
 472	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME) | \
 473		BIT(IIO_CHAN_INFO_SCALE) | \
 474		BIT(IIO_CHAN_INFO_HARDWAREGAIN), \
 475
 476static const struct iio_chan_spec si1133_channels[] = {
 477	{
 478		.type = IIO_LIGHT,
 479		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
 480		.channel = 0,
 481	},
 482	{
 483		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_WHITE, IIO_INTENSITY)
 484		.channel2 = IIO_MOD_LIGHT_BOTH,
 485	},
 486	{
 487		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_LARGE_WHITE, IIO_INTENSITY)
 488		.channel2 = IIO_MOD_LIGHT_BOTH,
 489		.extend_name = "large",
 490	},
 491	{
 492		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_SMALL_IR, IIO_INTENSITY)
 493		.extend_name = "small",
 494		.modified = 1,
 495		.channel2 = IIO_MOD_LIGHT_IR,
 496	},
 497	{
 498		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_MED_IR, IIO_INTENSITY)
 499		.modified = 1,
 500		.channel2 = IIO_MOD_LIGHT_IR,
 501	},
 502	{
 503		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_LARGE_IR, IIO_INTENSITY)
 504		.extend_name = "large",
 505		.modified = 1,
 506		.channel2 = IIO_MOD_LIGHT_IR,
 507	},
 508	{
 509		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_UV, IIO_UVINDEX)
 510	},
 511	{
 512		SI1133_CHANNEL(SI1133_PARAM_ADCMUX_UV_DEEP, IIO_UVINDEX)
 513		.modified = 1,
 514		.channel2 = IIO_MOD_LIGHT_DUV,
 515	}
 516};
 517
 518static int si1133_get_int_time_index(int milliseconds, int nanoseconds)
 519{
 520	int i;
 521
 522	for (i = 0; i < ARRAY_SIZE(si1133_int_time_table); i++) {
 523		if (milliseconds == si1133_int_time_table[i][0] &&
 524		    nanoseconds == si1133_int_time_table[i][1])
 525			return i;
 526	}
 527	return -EINVAL;
 528}
 529
 530static int si1133_set_integration_time(struct si1133_data *data, u8 adc,
 531				       int milliseconds, int nanoseconds)
 532{
 533	int index;
 534
 535	index = si1133_get_int_time_index(milliseconds, nanoseconds);
 536	if (index < 0)
 537		return index;
 538
 539	data->adc_sens[adc] &= 0xF0;
 540	data->adc_sens[adc] |= index;
 541
 542	return si1133_param_set(data, SI1133_PARAM_REG_ADCSENS(0),
 543				data->adc_sens[adc]);
 544}
 545
 546static int si1133_set_chlist(struct si1133_data *data, u8 scan_mask)
 547{
 548	/* channel list already set, no need to reprogram */
 549	if (data->scan_mask == scan_mask)
 550		return 0;
 551
 552	data->scan_mask = scan_mask;
 553
 554	return si1133_param_set(data, SI1133_PARAM_REG_CHAN_LIST, scan_mask);
 555}
 556
 557static int si1133_chan_set_adcconfig(struct si1133_data *data, u8 adc,
 558				     u8 adc_config)
 559{
 560	int err;
 561
 562	err = si1133_param_set(data, SI1133_PARAM_REG_ADCCONFIG(adc),
 563			       adc_config);
 564	if (err)
 565		return err;
 566
 567	data->adc_config[adc] = adc_config;
 568
 569	return 0;
 570}
 571
 572static int si1133_update_adcconfig(struct si1133_data *data, uint8_t adc,
 573				   u8 mask, u8 shift, u8 value)
 574{
 575	u32 adc_config;
 576	int err;
 577
 578	err = si1133_param_query(data, SI1133_PARAM_REG_ADCCONFIG(adc),
 579				 &adc_config);
 580	if (err)
 581		return err;
 582
 583	adc_config &= ~mask;
 584	adc_config |= (value << shift);
 585
 586	return si1133_chan_set_adcconfig(data, adc, adc_config);
 587}
 588
 589static int si1133_set_adcmux(struct si1133_data *data, u8 adc, u8 mux)
 590{
 591	if ((mux & data->adc_config[adc]) == mux)
 592		return 0; /* mux already set to correct value */
 593
 594	return si1133_update_adcconfig(data, adc, SI1133_ADCMUX_MASK, 0, mux);
 595}
 596
 597static int si1133_force_measurement(struct si1133_data *data)
 598{
 599	return si1133_command(data, SI1133_CMD_FORCE);
 600}
 601
 602static int si1133_bulk_read(struct si1133_data *data, u8 start_reg, u8 length,
 603			    u8 *buffer)
 604{
 605	int err;
 606
 607	err = si1133_force_measurement(data);
 608	if (err)
 609		return err;
 610
 611	return regmap_bulk_read(data->regmap, start_reg, buffer, length);
 612}
 613
 614static int si1133_measure(struct si1133_data *data,
 615			  struct iio_chan_spec const *chan,
 616			  int *val)
 617{
 618	int err;
 619
 620	u8 buffer[SI1133_MEASURE_BUFFER_SIZE];
 621
 622	err = si1133_set_adcmux(data, 0, chan->channel);
 623	if (err)
 624		return err;
 625
 626	/* Deactivate lux measurements if they were active */
 627	err = si1133_set_chlist(data, BIT(0));
 628	if (err)
 629		return err;
 630
 631	err = si1133_bulk_read(data, SI1133_REG_HOSTOUT(0), sizeof(buffer),
 632			       buffer);
 633	if (err)
 634		return err;
 635
 636	*val = sign_extend32(get_unaligned_be24(&buffer[0]), 23);
 637
 638	return err;
 639}
 640
 641static irqreturn_t si1133_threaded_irq_handler(int irq, void *private)
 642{
 643	struct iio_dev *iio_dev = private;
 644	struct si1133_data *data = iio_priv(iio_dev);
 645	u32 irq_status;
 646	int err;
 647
 648	err = regmap_read(data->regmap, SI1133_REG_IRQ_STATUS, &irq_status);
 649	if (err) {
 650		dev_err_ratelimited(&iio_dev->dev, "Error reading IRQ\n");
 651		goto out;
 652	}
 653
 654	if (irq_status != data->scan_mask)
 655		return IRQ_NONE;
 656
 657out:
 658	complete(&data->completion);
 659
 660	return IRQ_HANDLED;
 661}
 662
 663static int si1133_scale_to_swgain(int scale_integer, int scale_fractional)
 664{
 665	scale_integer = find_closest(scale_integer, si1133_scale_available,
 666				     ARRAY_SIZE(si1133_scale_available));
 667	if (scale_integer < 0 ||
 668	    scale_integer > ARRAY_SIZE(si1133_scale_available) ||
 669	    scale_fractional != 0)
 670		return -EINVAL;
 671
 672	return scale_integer;
 673}
 674
 675static int si1133_chan_set_adcsens(struct si1133_data *data, u8 adc,
 676				   u8 adc_sens)
 677{
 678	int err;
 679
 680	err = si1133_param_set(data, SI1133_PARAM_REG_ADCSENS(adc), adc_sens);
 681	if (err)
 682		return err;
 683
 684	data->adc_sens[adc] = adc_sens;
 685
 686	return 0;
 687}
 688
 689static int si1133_update_adcsens(struct si1133_data *data, u8 mask,
 690				 u8 shift, u8 value)
 691{
 692	int err;
 693	u32 adc_sens;
 694
 695	err = si1133_param_query(data, SI1133_PARAM_REG_ADCSENS(0),
 696				 &adc_sens);
 697	if (err)
 698		return err;
 699
 700	adc_sens &= ~mask;
 701	adc_sens |= (value << shift);
 702
 703	return si1133_chan_set_adcsens(data, 0, adc_sens);
 704}
 705
 706static int si1133_get_lux(struct si1133_data *data, int *val)
 707{
 708	int err;
 709	int lux;
 710	s32 high_vis;
 711	s32 low_vis;
 712	s32 ir;
 713	u8 buffer[SI1133_LUX_BUFFER_SIZE];
 714
 715	/* Activate lux channels */
 716	err = si1133_set_chlist(data, SI1133_LUX_ADC_MASK);
 717	if (err)
 718		return err;
 719
 720	err = si1133_bulk_read(data, SI1133_REG_HOSTOUT(0),
 721			       SI1133_LUX_BUFFER_SIZE, buffer);
 722	if (err)
 723		return err;
 724
 725	high_vis = sign_extend32(get_unaligned_be24(&buffer[0]), 23);
 726
 727	low_vis = sign_extend32(get_unaligned_be24(&buffer[3]), 23);
 728
 729	ir = sign_extend32(get_unaligned_be24(&buffer[6]), 23);
 730
 731	if (high_vis > SI1133_ADC_THRESHOLD || ir > SI1133_ADC_THRESHOLD)
 732		lux = si1133_calc_polynomial(high_vis, ir,
 733					     SI1133_INPUT_FRACTION_HIGH,
 734					     ARRAY_SIZE(lux_coeff.coeff_high),
 735					     &lux_coeff.coeff_high[0]);
 736	else
 737		lux = si1133_calc_polynomial(low_vis, ir,
 738					     SI1133_INPUT_FRACTION_LOW,
 739					     ARRAY_SIZE(lux_coeff.coeff_low),
 740					     &lux_coeff.coeff_low[0]);
 741
 742	*val = lux >> SI1133_LUX_OUTPUT_FRACTION;
 743
 744	return err;
 745}
 746
 747static int si1133_read_raw(struct iio_dev *iio_dev,
 748			   struct iio_chan_spec const *chan,
 749			   int *val, int *val2, long mask)
 750{
 751	struct si1133_data *data = iio_priv(iio_dev);
 752	u8 adc_sens = data->adc_sens[0];
 753	int err;
 754
 755	switch (mask) {
 756	case IIO_CHAN_INFO_PROCESSED:
 757		switch (chan->type) {
 758		case IIO_LIGHT:
 759			err = si1133_get_lux(data, val);
 760			if (err)
 761				return err;
 762
 763			return IIO_VAL_INT;
 764		default:
 765			return -EINVAL;
 766		}
 767	case IIO_CHAN_INFO_RAW:
 768		switch (chan->type) {
 769		case IIO_INTENSITY:
 770		case IIO_UVINDEX:
 771			err = si1133_measure(data, chan, val);
 772			if (err)
 773				return err;
 774
 775			return IIO_VAL_INT;
 776		default:
 777			return -EINVAL;
 778		}
 779	case IIO_CHAN_INFO_INT_TIME:
 780		switch (chan->type) {
 781		case IIO_INTENSITY:
 782		case IIO_UVINDEX:
 783			adc_sens &= SI1133_ADCSENS_HW_GAIN_MASK;
 784
 785			*val = si1133_int_time_table[adc_sens][0];
 786			*val2 = si1133_int_time_table[adc_sens][1];
 787			return IIO_VAL_INT_PLUS_MICRO;
 788		default:
 789			return -EINVAL;
 790		}
 791	case IIO_CHAN_INFO_SCALE:
 792		switch (chan->type) {
 793		case IIO_INTENSITY:
 794		case IIO_UVINDEX:
 795			adc_sens &= SI1133_ADCSENS_SCALE_MASK;
 796			adc_sens >>= SI1133_ADCSENS_SCALE_SHIFT;
 797
 798			*val = BIT(adc_sens);
 799
 800			return IIO_VAL_INT;
 801		default:
 802			return -EINVAL;
 803		}
 804	case IIO_CHAN_INFO_HARDWAREGAIN:
 805		switch (chan->type) {
 806		case IIO_INTENSITY:
 807		case IIO_UVINDEX:
 808			adc_sens >>= SI1133_ADCSENS_HSIG_SHIFT;
 809
 810			*val = adc_sens;
 811
 812			return IIO_VAL_INT;
 813		default:
 814			return -EINVAL;
 815		}
 816	default:
 817		return -EINVAL;
 818	}
 819}
 820
 821static int si1133_write_raw(struct iio_dev *iio_dev,
 822			    struct iio_chan_spec const *chan,
 823			    int val, int val2, long mask)
 824{
 825	struct si1133_data *data = iio_priv(iio_dev);
 826
 827	switch (mask) {
 828	case IIO_CHAN_INFO_SCALE:
 829		switch (chan->type) {
 830		case IIO_INTENSITY:
 831		case IIO_UVINDEX:
 832			val = si1133_scale_to_swgain(val, val2);
 833			if (val < 0)
 834				return val;
 835
 836			return si1133_update_adcsens(data,
 837						     SI1133_ADCSENS_SCALE_MASK,
 838						     SI1133_ADCSENS_SCALE_SHIFT,
 839						     val);
 840		default:
 841			return -EINVAL;
 842		}
 843	case IIO_CHAN_INFO_INT_TIME:
 844		return si1133_set_integration_time(data, 0, val, val2);
 845	case IIO_CHAN_INFO_HARDWAREGAIN:
 846		switch (chan->type) {
 847		case IIO_INTENSITY:
 848		case IIO_UVINDEX:
 849			if (val != 0 && val != 1)
 850				return -EINVAL;
 851
 852			return si1133_update_adcsens(data,
 853						     SI1133_ADCSENS_HSIG_MASK,
 854						     SI1133_ADCSENS_HSIG_SHIFT,
 855						     val);
 856		default:
 857			return -EINVAL;
 858		}
 859	default:
 860		return -EINVAL;
 861	}
 862}
 863
 864static struct attribute *si1133_attributes[] = {
 865	&iio_const_attr_integration_time_available.dev_attr.attr,
 866	&iio_const_attr_scale_available.dev_attr.attr,
 867	NULL,
 868};
 869
 870static const struct attribute_group si1133_attribute_group = {
 871	.attrs = si1133_attributes,
 872};
 873
 874static const struct iio_info si1133_info = {
 875	.read_raw = si1133_read_raw,
 876	.write_raw = si1133_write_raw,
 877	.attrs = &si1133_attribute_group,
 878};
 879
 880/*
 881 * si1133_init_lux_channels - Configure 3 different channels(adc) (1,2 and 3)
 882 * The channel configuration for the lux measurement was taken from :
 883 * https://siliconlabs.github.io/Gecko_SDK_Doc/efm32zg/html/si1133_8c_source.html#l00578
 884 *
 885 * Reserved the channel 0 for the other raw measurements
 886 */
 887static int si1133_init_lux_channels(struct si1133_data *data)
 888{
 889	int err;
 890
 891	err = si1133_chan_set_adcconfig(data, 1,
 892					SI1133_ADCCONFIG_DECIM_RATE(1) |
 893					SI1133_PARAM_ADCMUX_LARGE_WHITE);
 894	if (err)
 895		return err;
 896
 897	err = si1133_param_set(data, SI1133_PARAM_REG_ADCPOST(1),
 898			       SI1133_ADCPOST_24BIT_EN |
 899			       SI1133_ADCPOST_POSTSHIFT_BITQTY(0));
 900	if (err)
 901		return err;
 902	err = si1133_chan_set_adcsens(data, 1, SI1133_ADCSENS_HSIG_MASK |
 903				      SI1133_ADCSENS_NB_MEAS(64) | _48_8_us);
 904	if (err)
 905		return err;
 906
 907	err = si1133_chan_set_adcconfig(data, 2,
 908					SI1133_ADCCONFIG_DECIM_RATE(1) |
 909					SI1133_PARAM_ADCMUX_LARGE_WHITE);
 910	if (err)
 911		return err;
 912
 913	err = si1133_param_set(data, SI1133_PARAM_REG_ADCPOST(2),
 914			       SI1133_ADCPOST_24BIT_EN |
 915			       SI1133_ADCPOST_POSTSHIFT_BITQTY(2));
 916	if (err)
 917		return err;
 918
 919	err = si1133_chan_set_adcsens(data, 2, SI1133_ADCSENS_HSIG_MASK |
 920				      SI1133_ADCSENS_NB_MEAS(1) | _3_120_0_us);
 921	if (err)
 922		return err;
 923
 924	err = si1133_chan_set_adcconfig(data, 3,
 925					SI1133_ADCCONFIG_DECIM_RATE(1) |
 926					SI1133_PARAM_ADCMUX_MED_IR);
 927	if (err)
 928		return err;
 929
 930	err = si1133_param_set(data, SI1133_PARAM_REG_ADCPOST(3),
 931			       SI1133_ADCPOST_24BIT_EN |
 932			       SI1133_ADCPOST_POSTSHIFT_BITQTY(2));
 933	if (err)
 934		return err;
 935
 936	return  si1133_chan_set_adcsens(data, 3, SI1133_ADCSENS_HSIG_MASK |
 937					SI1133_ADCSENS_NB_MEAS(64) | _48_8_us);
 938}
 939
 940static int si1133_initialize(struct si1133_data *data)
 941{
 942	int err;
 943
 944	err = si1133_cmd_reset_sw(data);
 945	if (err)
 946		return err;
 947
 948	/* Turn off autonomous mode */
 949	err = si1133_param_set(data, SI1133_REG_MEAS_RATE, 0);
 950	if (err)
 951		return err;
 952
 953	err = si1133_init_lux_channels(data);
 954	if (err)
 955		return err;
 956
 957	return regmap_write(data->regmap, SI1133_REG_IRQ_ENABLE,
 958			    SI1133_IRQ_CHANNEL_ENABLE);
 959}
 960
 961static int si1133_validate_ids(struct iio_dev *iio_dev)
 962{
 963	struct si1133_data *data = iio_priv(iio_dev);
 964
 965	unsigned int part_id, rev_id, mfr_id;
 966	int err;
 967
 968	err = regmap_read(data->regmap, SI1133_REG_PART_ID, &part_id);
 969	if (err)
 970		return err;
 971
 972	err = regmap_read(data->regmap, SI1133_REG_REV_ID, &rev_id);
 973	if (err)
 974		return err;
 975
 976	err = regmap_read(data->regmap, SI1133_REG_MFR_ID, &mfr_id);
 977	if (err)
 978		return err;
 979
 980	dev_info(&iio_dev->dev,
 981		 "Device ID part 0x%02x rev 0x%02x mfr 0x%02x\n",
 982		 part_id, rev_id, mfr_id);
 983	if (part_id != SI1133_PART_ID) {
 984		dev_err(&iio_dev->dev,
 985			"Part ID mismatch got 0x%02x, expected 0x%02x\n",
 986			part_id, SI1133_PART_ID);
 987		return -ENODEV;
 988	}
 989
 990	return 0;
 991}
 992
 993static int si1133_probe(struct i2c_client *client)
 994{
 995	const struct i2c_device_id *id = i2c_client_get_device_id(client);
 996	struct si1133_data *data;
 997	struct iio_dev *iio_dev;
 998	int err;
 999
1000	iio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
1001	if (!iio_dev)
1002		return -ENOMEM;
1003
1004	data = iio_priv(iio_dev);
1005
1006	init_completion(&data->completion);
1007
1008	data->regmap = devm_regmap_init_i2c(client, &si1133_regmap_config);
1009	if (IS_ERR(data->regmap)) {
1010		err = PTR_ERR(data->regmap);
1011		dev_err(&client->dev, "Failed to initialise regmap: %d\n", err);
1012		return err;
1013	}
1014
1015	i2c_set_clientdata(client, iio_dev);
1016	data->client = client;
1017
1018	iio_dev->name = id->name;
1019	iio_dev->channels = si1133_channels;
1020	iio_dev->num_channels = ARRAY_SIZE(si1133_channels);
1021	iio_dev->info = &si1133_info;
1022	iio_dev->modes = INDIO_DIRECT_MODE;
1023
1024	mutex_init(&data->mutex);
1025
1026	err = si1133_validate_ids(iio_dev);
1027	if (err)
1028		return err;
1029
1030	err = si1133_initialize(data);
1031	if (err) {
1032		dev_err(&client->dev,
1033			"Error when initializing chip: %d\n", err);
1034		return err;
1035	}
1036
1037	if (!client->irq) {
1038		dev_err(&client->dev,
1039			"Required interrupt not provided, cannot proceed\n");
1040		return -EINVAL;
1041	}
1042
1043	err = devm_request_threaded_irq(&client->dev, client->irq,
1044					NULL,
1045					si1133_threaded_irq_handler,
1046					IRQF_ONESHOT | IRQF_SHARED,
1047					client->name, iio_dev);
1048	if (err) {
1049		dev_warn(&client->dev, "Request irq %d failed: %i\n",
1050			 client->irq, err);
1051		return err;
1052	}
1053
1054	return devm_iio_device_register(&client->dev, iio_dev);
1055}
1056
1057static const struct i2c_device_id si1133_ids[] = {
1058	{ "si1133" },
1059	{ }
1060};
1061MODULE_DEVICE_TABLE(i2c, si1133_ids);
1062
1063static struct i2c_driver si1133_driver = {
1064	.driver = {
1065	    .name   = "si1133",
1066	},
1067	.probe = si1133_probe,
1068	.id_table = si1133_ids,
1069};
1070
1071module_i2c_driver(si1133_driver);
1072
1073MODULE_AUTHOR("Maxime Roussin-Belanger <maxime.roussinbelanger@gmail.com>");
1074MODULE_DESCRIPTION("Silabs SI1133, UV index sensor and ambient light sensor driver");
1075MODULE_LICENSE("GPL");
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