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
109 static const int si1133_scale_available[] = {
110 1, 2, 4, 8, 16, 32, 64, 128};
111
112 static IIO_CONST_ATTR(scale_available, "1 2 4 8 16 32 64 128");
113
114 static 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 */
118 enum 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 */
134 static 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
149 static 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
157 static const struct regmap_range si1133_reg_ro_ranges[] = {
158 regmap_reg_range(0x00, 0x02),
159 regmap_reg_range(0x10, 0x2C),
160 };
161
162 static const struct regmap_range si1133_precious_ranges[] = {
163 regmap_reg_range(0x12, 0x12),
164 };
165
166 static 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
173 static 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
178 static 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
183 static 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
195 struct 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
210 struct si1133_coeff {
211 s16 info;
212 u16 mag;
213 };
214
215 struct si1133_lux_coeff {
216 struct si1133_coeff coeff_high[4];
217 struct si1133_coeff coeff_low[9];
218 };
219
220 static 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
si1133_calculate_polynomial_inner(s32 input,u8 fraction,u16 mag,s8 shift)240 static int si1133_calculate_polynomial_inner(s32 input, u8 fraction, u16 mag,
241 s8 shift)
242 {
243 return ((input << fraction) / mag) << shift;
244 }
245
si1133_calculate_output(s32 x,s32 y,u8 x_order,u8 y_order,u8 input_fraction,s8 sign,const struct si1133_coeff * coeffs)246 static 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 */
si1133_calc_polynomial(s32 x,s32 y,u8 input_fraction,u8 num_coeff,const struct si1133_coeff * coeffs)282 static 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
si1133_cmd_reset_sw(struct si1133_data * data)313 static 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
si1133_parse_response_err(struct device * dev,u32 resp,u8 cmd)349 static 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
si1133_cmd_reset_counter(struct si1133_data * data)375 static 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
si1133_command(struct si1133_data * data,u8 cmd)387 static 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
441 out:
442 mutex_unlock(&data->mutex);
443
444 return err;
445 }
446
si1133_param_set(struct si1133_data * data,u8 param,u32 value)447 static 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
si1133_param_query(struct si1133_data * data,u8 param,u32 * result)458 static 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
476 static 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
si1133_get_int_time_index(int milliseconds,int nanoseconds)518 static 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
si1133_set_integration_time(struct si1133_data * data,u8 adc,int milliseconds,int nanoseconds)530 static 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
si1133_set_chlist(struct si1133_data * data,u8 scan_mask)546 static 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
si1133_chan_set_adcconfig(struct si1133_data * data,u8 adc,u8 adc_config)557 static 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
si1133_update_adcconfig(struct si1133_data * data,uint8_t adc,u8 mask,u8 shift,u8 value)572 static 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
si1133_set_adcmux(struct si1133_data * data,u8 adc,u8 mux)589 static 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
si1133_force_measurement(struct si1133_data * data)597 static int si1133_force_measurement(struct si1133_data *data)
598 {
599 return si1133_command(data, SI1133_CMD_FORCE);
600 }
601
si1133_bulk_read(struct si1133_data * data,u8 start_reg,u8 length,u8 * buffer)602 static 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
si1133_measure(struct si1133_data * data,struct iio_chan_spec const * chan,int * val)614 static 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
si1133_threaded_irq_handler(int irq,void * private)641 static 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
657 out:
658 complete(&data->completion);
659
660 return IRQ_HANDLED;
661 }
662
si1133_scale_to_swgain(int scale_integer,int scale_fractional)663 static 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
si1133_chan_set_adcsens(struct si1133_data * data,u8 adc,u8 adc_sens)675 static 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
si1133_update_adcsens(struct si1133_data * data,u8 mask,u8 shift,u8 value)689 static 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
si1133_get_lux(struct si1133_data * data,int * val)706 static 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
si1133_read_raw(struct iio_dev * iio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)747 static 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
si1133_write_raw(struct iio_dev * iio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)821 static 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
864 static 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
870 static const struct attribute_group si1133_attribute_group = {
871 .attrs = si1133_attributes,
872 };
873
874 static 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 */
si1133_init_lux_channels(struct si1133_data * data)887 static 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
si1133_initialize(struct si1133_data * data)940 static 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
si1133_validate_ids(struct iio_dev * iio_dev)961 static 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
si1133_probe(struct i2c_client * client)993 static 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
1057 static const struct i2c_device_id si1133_ids[] = {
1058 { "si1133" },
1059 { }
1060 };
1061 MODULE_DEVICE_TABLE(i2c, si1133_ids);
1062
1063 static struct i2c_driver si1133_driver = {
1064 .driver = {
1065 .name = "si1133",
1066 },
1067 .probe = si1133_probe,
1068 .id_table = si1133_ids,
1069 };
1070
1071 module_i2c_driver(si1133_driver);
1072
1073 MODULE_AUTHOR("Maxime Roussin-Belanger <maxime.roussinbelanger@gmail.com>");
1074 MODULE_DESCRIPTION("Silabs SI1133, UV index sensor and ambient light sensor driver");
1075 MODULE_LICENSE("GPL");
1076