1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * mlx90635.c - Melexis MLX90635 contactless IR temperature sensor
4 *
5 * Copyright (c) 2023 Melexis <cmo@melexis.com>
6 *
7 * Driver for the Melexis MLX90635 I2C 16-bit IR thermopile sensor
8 */
9 #include <linux/bitfield.h>
10 #include <linux/delay.h>
11 #include <linux/device.h>
12 #include <linux/err.h>
13 #include <linux/gpio/consumer.h>
14 #include <linux/i2c.h>
15 #include <linux/iopoll.h>
16 #include <linux/jiffies.h>
17 #include <linux/kernel.h>
18 #include <linux/limits.h>
19 #include <linux/module.h>
20 #include <linux/math64.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/regmap.h>
23 #include <linux/regulator/consumer.h>
24
25 #include <linux/iio/iio.h>
26
27 /* Memory sections addresses */
28 #define MLX90635_ADDR_RAM 0x0000 /* Start address of ram */
29 #define MLX90635_ADDR_EEPROM 0x0018 /* Start address of user eeprom */
30
31 /* EEPROM addresses - used at startup */
32 #define MLX90635_EE_I2C_CFG 0x0018 /* I2C address register initial value */
33 #define MLX90635_EE_CTRL1 0x001A /* Control register1 initial value */
34 #define MLX90635_EE_CTRL2 0x001C /* Control register2 initial value */
35
36 #define MLX90635_EE_Ha 0x001E /* Ha customer calib value reg 16bit */
37 #define MLX90635_EE_Hb 0x0020 /* Hb customer calib value reg 16bit */
38 #define MLX90635_EE_Fa 0x0026 /* Fa calibration register 32bit */
39 #define MLX90635_EE_FASCALE 0x002A /* Scaling coefficient for Fa register 16bit */
40 #define MLX90635_EE_Ga 0x002C /* Ga calibration register 16bit */
41 #define MLX90635_EE_Fb 0x002E /* Fb calibration register 16bit */
42 #define MLX90635_EE_Ea 0x0030 /* Ea calibration register 32bit */
43 #define MLX90635_EE_Eb 0x0034 /* Eb calibration register 32bit */
44 #define MLX90635_EE_P_G 0x0038 /* P_G calibration register 16bit */
45 #define MLX90635_EE_P_O 0x003A /* P_O calibration register 16bit */
46 #define MLX90635_EE_Aa 0x003C /* Aa calibration register 16bit */
47 #define MLX90635_EE_VERSION 0x003E /* Version bits 4:7 and 12:15 */
48 #define MLX90635_EE_Gb 0x0040 /* Gb calibration register 16bit */
49
50 /* Device status register - volatile */
51 #define MLX90635_REG_STATUS 0x0000
52 #define MLX90635_STAT_BUSY BIT(6) /* Device busy indicator */
53 #define MLX90635_STAT_BRST BIT(5) /* Brown out reset indicator */
54 #define MLX90635_STAT_CYCLE_POS GENMASK(4, 2) /* Data position */
55 #define MLX90635_STAT_END_CONV BIT(1) /* End of conversion indicator */
56 #define MLX90635_STAT_DATA_RDY BIT(0) /* Data ready indicator */
57
58 /* EEPROM control register address - volatile */
59 #define MLX90635_REG_EE 0x000C
60 #define MLX90635_EE_ACTIVE BIT(4) /* Power-on EEPROM */
61 #define MLX90635_EE_BUSY_MASK BIT(15)
62
63 #define MLX90635_REG_CMD 0x0010 /* Command register address */
64
65 /* Control register1 address - volatile */
66 #define MLX90635_REG_CTRL1 0x0014
67 #define MLX90635_CTRL1_REFRESH_RATE_MASK GENMASK(2, 0)
68 #define MLX90635_CTRL1_RES_CTRL_MASK GENMASK(4, 3)
69 #define MLX90635_CTRL1_TABLE_MASK BIT(15) /* Table select */
70
71 /* Control register2 address - volatile */
72 #define MLX90635_REG_CTRL2 0x0016
73 #define MLX90635_CTRL2_BURST_CNT_MASK GENMASK(10, 6) /* Burst count */
74 #define MLX90635_CTRL2_MODE_MASK GENMASK(12, 11) /* Power mode */
75 #define MLX90635_CTRL2_SOB_MASK BIT(15)
76
77 /* PowerModes statuses */
78 #define MLX90635_PWR_STATUS_HALT 0
79 #define MLX90635_PWR_STATUS_SLEEP_STEP 1
80 #define MLX90635_PWR_STATUS_STEP 2
81 #define MLX90635_PWR_STATUS_CONTINUOUS 3
82
83 /* Measurement data addresses */
84 #define MLX90635_RESULT_1 0x0002
85 #define MLX90635_RESULT_2 0x0004
86 #define MLX90635_RESULT_3 0x0006
87 #define MLX90635_RESULT_4 0x0008
88 #define MLX90635_RESULT_5 0x000A
89
90 /* Timings (ms) */
91 #define MLX90635_TIMING_RST_MIN 200 /* Minimum time after addressed reset command */
92 #define MLX90635_TIMING_RST_MAX 250 /* Maximum time after addressed reset command */
93 #define MLX90635_TIMING_POLLING 10000 /* Time between bit polling*/
94 #define MLX90635_TIMING_EE_ACTIVE_MIN 100 /* Minimum time after activating the EEPROM for read */
95 #define MLX90635_TIMING_EE_ACTIVE_MAX 150 /* Maximum time after activating the EEPROM for read */
96
97 /* Magic constants */
98 #define MLX90635_ID_DSPv1 0x01 /* EEPROM DSP version */
99 #define MLX90635_RESET_CMD 0x0006 /* Reset sensor (address or global) */
100 #define MLX90635_MAX_MEAS_NUM 31 /* Maximum number of measurements in list */
101 #define MLX90635_PTAT_DIV 12 /* Used to divide the PTAT value in pre-processing */
102 #define MLX90635_IR_DIV 24 /* Used to divide the IR value in pre-processing */
103 #define MLX90635_SLEEP_DELAY_MS 6000 /* Autosleep delay */
104 #define MLX90635_MEAS_MAX_TIME 2000 /* Max measurement time in ms for the lowest refresh rate */
105 #define MLX90635_READ_RETRIES 100 /* Number of read retries before quitting with timeout error */
106 #define MLX90635_VERSION_MASK (GENMASK(15, 12) | GENMASK(7, 4))
107 #define MLX90635_DSP_VERSION(reg) (((reg & GENMASK(14, 12)) >> 9) | ((reg & GENMASK(6, 4)) >> 4))
108 #define MLX90635_DSP_FIXED BIT(15)
109
110
111 /**
112 * struct mlx90635_data - private data for the MLX90635 device
113 * @client: I2C client of the device
114 * @lock: Internal mutex because multiple reads are needed for single triggered
115 * measurement to ensure data consistency
116 * @regmap: Regmap of the device registers
117 * @regmap_ee: Regmap of the device EEPROM which can be cached
118 * @emissivity: Object emissivity from 0 to 1000 where 1000 = 1
119 * @regulator: Regulator of the device
120 * @powerstatus: Current POWER status of the device
121 * @interaction_ts: Timestamp of the last temperature read that is used
122 * for power management in jiffies
123 */
124 struct mlx90635_data {
125 struct i2c_client *client;
126 struct mutex lock;
127 struct regmap *regmap;
128 struct regmap *regmap_ee;
129 u16 emissivity;
130 struct regulator *regulator;
131 int powerstatus;
132 unsigned long interaction_ts;
133 };
134
135 static const struct regmap_range mlx90635_volatile_reg_range[] = {
136 regmap_reg_range(MLX90635_REG_STATUS, MLX90635_REG_STATUS),
137 regmap_reg_range(MLX90635_RESULT_1, MLX90635_RESULT_5),
138 regmap_reg_range(MLX90635_REG_EE, MLX90635_REG_EE),
139 regmap_reg_range(MLX90635_REG_CMD, MLX90635_REG_CMD),
140 regmap_reg_range(MLX90635_REG_CTRL1, MLX90635_REG_CTRL2),
141 };
142
143 static const struct regmap_access_table mlx90635_volatile_regs_tbl = {
144 .yes_ranges = mlx90635_volatile_reg_range,
145 .n_yes_ranges = ARRAY_SIZE(mlx90635_volatile_reg_range),
146 };
147
148 static const struct regmap_range mlx90635_read_reg_range[] = {
149 regmap_reg_range(MLX90635_REG_STATUS, MLX90635_REG_STATUS),
150 regmap_reg_range(MLX90635_RESULT_1, MLX90635_RESULT_5),
151 regmap_reg_range(MLX90635_REG_EE, MLX90635_REG_EE),
152 regmap_reg_range(MLX90635_REG_CMD, MLX90635_REG_CMD),
153 regmap_reg_range(MLX90635_REG_CTRL1, MLX90635_REG_CTRL2),
154 };
155
156 static const struct regmap_access_table mlx90635_readable_regs_tbl = {
157 .yes_ranges = mlx90635_read_reg_range,
158 .n_yes_ranges = ARRAY_SIZE(mlx90635_read_reg_range),
159 };
160
161 static const struct regmap_range mlx90635_no_write_reg_range[] = {
162 regmap_reg_range(MLX90635_RESULT_1, MLX90635_RESULT_5),
163 };
164
165 static const struct regmap_access_table mlx90635_writeable_regs_tbl = {
166 .no_ranges = mlx90635_no_write_reg_range,
167 .n_no_ranges = ARRAY_SIZE(mlx90635_no_write_reg_range),
168 };
169
170 static const struct regmap_config mlx90635_regmap = {
171 .name = "mlx90635-registers",
172 .reg_stride = 1,
173 .reg_bits = 16,
174 .val_bits = 16,
175
176 .volatile_table = &mlx90635_volatile_regs_tbl,
177 .rd_table = &mlx90635_readable_regs_tbl,
178 .wr_table = &mlx90635_writeable_regs_tbl,
179
180 .use_single_read = true,
181 .use_single_write = true,
182 .can_multi_write = false,
183 .reg_format_endian = REGMAP_ENDIAN_BIG,
184 .val_format_endian = REGMAP_ENDIAN_BIG,
185 .cache_type = REGCACHE_RBTREE,
186 };
187
188 static const struct regmap_range mlx90635_read_ee_range[] = {
189 regmap_reg_range(MLX90635_EE_I2C_CFG, MLX90635_EE_CTRL2),
190 regmap_reg_range(MLX90635_EE_Ha, MLX90635_EE_Gb),
191 };
192
193 static const struct regmap_access_table mlx90635_readable_ees_tbl = {
194 .yes_ranges = mlx90635_read_ee_range,
195 .n_yes_ranges = ARRAY_SIZE(mlx90635_read_ee_range),
196 };
197
198 static const struct regmap_range mlx90635_no_write_ee_range[] = {
199 regmap_reg_range(MLX90635_ADDR_EEPROM, MLX90635_EE_Gb),
200 };
201
202 static const struct regmap_access_table mlx90635_writeable_ees_tbl = {
203 .no_ranges = mlx90635_no_write_ee_range,
204 .n_no_ranges = ARRAY_SIZE(mlx90635_no_write_ee_range),
205 };
206
207 static const struct regmap_config mlx90635_regmap_ee = {
208 .name = "mlx90635-eeprom",
209 .reg_stride = 1,
210 .reg_bits = 16,
211 .val_bits = 16,
212
213 .volatile_table = NULL,
214 .rd_table = &mlx90635_readable_ees_tbl,
215 .wr_table = &mlx90635_writeable_ees_tbl,
216
217 .use_single_read = true,
218 .use_single_write = true,
219 .can_multi_write = false,
220 .reg_format_endian = REGMAP_ENDIAN_BIG,
221 .val_format_endian = REGMAP_ENDIAN_BIG,
222 .cache_type = REGCACHE_RBTREE,
223 };
224
225 /**
226 * mlx90635_reset_delay() - Give the mlx90635 some time to reset properly
227 * If this is not done, the following I2C command(s) will not be accepted.
228 */
mlx90635_reset_delay(void)229 static void mlx90635_reset_delay(void)
230 {
231 usleep_range(MLX90635_TIMING_RST_MIN, MLX90635_TIMING_RST_MAX);
232 }
233
mlx90635_pwr_sleep_step(struct mlx90635_data * data)234 static int mlx90635_pwr_sleep_step(struct mlx90635_data *data)
235 {
236 int ret;
237
238 if (data->powerstatus == MLX90635_PWR_STATUS_SLEEP_STEP)
239 return 0;
240
241 ret = regmap_write_bits(data->regmap, MLX90635_REG_CTRL2, MLX90635_CTRL2_MODE_MASK,
242 FIELD_PREP(MLX90635_CTRL2_MODE_MASK, MLX90635_PWR_STATUS_SLEEP_STEP));
243 if (ret < 0)
244 return ret;
245
246 data->powerstatus = MLX90635_PWR_STATUS_SLEEP_STEP;
247 return 0;
248 }
249
mlx90635_pwr_continuous(struct mlx90635_data * data)250 static int mlx90635_pwr_continuous(struct mlx90635_data *data)
251 {
252 int ret;
253
254 if (data->powerstatus == MLX90635_PWR_STATUS_CONTINUOUS)
255 return 0;
256
257 ret = regmap_write_bits(data->regmap, MLX90635_REG_CTRL2, MLX90635_CTRL2_MODE_MASK,
258 FIELD_PREP(MLX90635_CTRL2_MODE_MASK, MLX90635_PWR_STATUS_CONTINUOUS));
259 if (ret < 0)
260 return ret;
261
262 data->powerstatus = MLX90635_PWR_STATUS_CONTINUOUS;
263 return 0;
264 }
265
mlx90635_read_ee_register(struct regmap * regmap,u16 reg_lsb,s32 * reg_value)266 static int mlx90635_read_ee_register(struct regmap *regmap, u16 reg_lsb,
267 s32 *reg_value)
268 {
269 unsigned int read;
270 u32 value;
271 int ret;
272
273 ret = regmap_read(regmap, reg_lsb + 2, &read);
274 if (ret < 0)
275 return ret;
276
277 value = read;
278
279 ret = regmap_read(regmap, reg_lsb, &read);
280 if (ret < 0)
281 return ret;
282
283 *reg_value = (read << 16) | (value & 0xffff);
284
285 return 0;
286 }
287
mlx90635_read_ee_ambient(struct regmap * regmap,s16 * PG,s16 * PO,s16 * Gb)288 static int mlx90635_read_ee_ambient(struct regmap *regmap, s16 *PG, s16 *PO, s16 *Gb)
289 {
290 unsigned int read_tmp;
291 int ret;
292
293 ret = regmap_read(regmap, MLX90635_EE_P_O, &read_tmp);
294 if (ret < 0)
295 return ret;
296 *PO = (s16)read_tmp;
297
298 ret = regmap_read(regmap, MLX90635_EE_P_G, &read_tmp);
299 if (ret < 0)
300 return ret;
301 *PG = (s16)read_tmp;
302
303 ret = regmap_read(regmap, MLX90635_EE_Gb, &read_tmp);
304 if (ret < 0)
305 return ret;
306 *Gb = (u16)read_tmp;
307
308 return 0;
309 }
310
mlx90635_read_ee_object(struct regmap * regmap,u32 * Ea,u32 * Eb,u32 * Fa,s16 * Fb,s16 * Ga,s16 * Gb,s16 * Ha,s16 * Hb,u16 * Fa_scale)311 static int mlx90635_read_ee_object(struct regmap *regmap, u32 *Ea, u32 *Eb, u32 *Fa, s16 *Fb,
312 s16 *Ga, s16 *Gb, s16 *Ha, s16 *Hb, u16 *Fa_scale)
313 {
314 unsigned int read_tmp;
315 int ret;
316
317 ret = mlx90635_read_ee_register(regmap, MLX90635_EE_Ea, Ea);
318 if (ret < 0)
319 return ret;
320
321 ret = mlx90635_read_ee_register(regmap, MLX90635_EE_Eb, Eb);
322 if (ret < 0)
323 return ret;
324
325 ret = mlx90635_read_ee_register(regmap, MLX90635_EE_Fa, Fa);
326 if (ret < 0)
327 return ret;
328
329 ret = regmap_read(regmap, MLX90635_EE_Ha, &read_tmp);
330 if (ret < 0)
331 return ret;
332 *Ha = (s16)read_tmp;
333
334 ret = regmap_read(regmap, MLX90635_EE_Hb, &read_tmp);
335 if (ret < 0)
336 return ret;
337 *Hb = (s16)read_tmp;
338
339 ret = regmap_read(regmap, MLX90635_EE_Ga, &read_tmp);
340 if (ret < 0)
341 return ret;
342 *Ga = (s16)read_tmp;
343
344 ret = regmap_read(regmap, MLX90635_EE_Gb, &read_tmp);
345 if (ret < 0)
346 return ret;
347 *Gb = (s16)read_tmp;
348
349 ret = regmap_read(regmap, MLX90635_EE_Fb, &read_tmp);
350 if (ret < 0)
351 return ret;
352 *Fb = (s16)read_tmp;
353
354 ret = regmap_read(regmap, MLX90635_EE_FASCALE, &read_tmp);
355 if (ret < 0)
356 return ret;
357 *Fa_scale = (u16)read_tmp;
358
359 return 0;
360 }
361
mlx90635_calculate_dataset_ready_time(struct mlx90635_data * data,int * refresh_time)362 static int mlx90635_calculate_dataset_ready_time(struct mlx90635_data *data, int *refresh_time)
363 {
364 unsigned int reg;
365 int ret;
366
367 ret = regmap_read(data->regmap, MLX90635_REG_CTRL1, ®);
368 if (ret < 0)
369 return ret;
370
371 *refresh_time = 2 * (MLX90635_MEAS_MAX_TIME >> FIELD_GET(MLX90635_CTRL1_REFRESH_RATE_MASK, reg)) + 80;
372
373 return 0;
374 }
375
mlx90635_perform_measurement_burst(struct mlx90635_data * data)376 static int mlx90635_perform_measurement_burst(struct mlx90635_data *data)
377 {
378 unsigned int reg_status;
379 int refresh_time;
380 int ret;
381
382 ret = regmap_write_bits(data->regmap, MLX90635_REG_STATUS,
383 MLX90635_STAT_END_CONV, MLX90635_STAT_END_CONV);
384 if (ret < 0)
385 return ret;
386
387 ret = mlx90635_calculate_dataset_ready_time(data, &refresh_time);
388 if (ret < 0)
389 return ret;
390
391 ret = regmap_write_bits(data->regmap, MLX90635_REG_CTRL2,
392 FIELD_PREP(MLX90635_CTRL2_SOB_MASK, 1),
393 FIELD_PREP(MLX90635_CTRL2_SOB_MASK, 1));
394 if (ret < 0)
395 return ret;
396
397 msleep(refresh_time); /* Wait minimum time for dataset to be ready */
398
399 ret = regmap_read_poll_timeout(data->regmap, MLX90635_REG_STATUS, reg_status,
400 (!(reg_status & MLX90635_STAT_END_CONV)) == 0,
401 MLX90635_TIMING_POLLING, MLX90635_READ_RETRIES * 10000);
402 if (ret < 0) {
403 dev_err(&data->client->dev, "data not ready");
404 return -ETIMEDOUT;
405 }
406
407 return 0;
408 }
409
mlx90635_read_ambient_raw(struct regmap * regmap,s16 * ambient_new_raw,s16 * ambient_old_raw)410 static int mlx90635_read_ambient_raw(struct regmap *regmap,
411 s16 *ambient_new_raw, s16 *ambient_old_raw)
412 {
413 unsigned int read_tmp;
414 int ret;
415
416 ret = regmap_read(regmap, MLX90635_RESULT_2, &read_tmp);
417 if (ret < 0)
418 return ret;
419 *ambient_new_raw = (s16)read_tmp;
420
421 ret = regmap_read(regmap, MLX90635_RESULT_3, &read_tmp);
422 if (ret < 0)
423 return ret;
424 *ambient_old_raw = (s16)read_tmp;
425
426 return 0;
427 }
428
mlx90635_read_object_raw(struct regmap * regmap,s16 * object_raw)429 static int mlx90635_read_object_raw(struct regmap *regmap, s16 *object_raw)
430 {
431 unsigned int read_tmp;
432 s16 read;
433 int ret;
434
435 ret = regmap_read(regmap, MLX90635_RESULT_1, &read_tmp);
436 if (ret < 0)
437 return ret;
438
439 read = (s16)read_tmp;
440
441 ret = regmap_read(regmap, MLX90635_RESULT_4, &read_tmp);
442 if (ret < 0)
443 return ret;
444 *object_raw = (read - (s16)read_tmp) / 2;
445
446 return 0;
447 }
448
mlx90635_read_all_channel(struct mlx90635_data * data,s16 * ambient_new_raw,s16 * ambient_old_raw,s16 * object_raw)449 static int mlx90635_read_all_channel(struct mlx90635_data *data,
450 s16 *ambient_new_raw, s16 *ambient_old_raw,
451 s16 *object_raw)
452 {
453 int ret;
454
455 mutex_lock(&data->lock);
456 if (data->powerstatus == MLX90635_PWR_STATUS_SLEEP_STEP) {
457 /* Trigger measurement in Sleep Step mode */
458 ret = mlx90635_perform_measurement_burst(data);
459 if (ret < 0)
460 goto read_unlock;
461 }
462
463 ret = mlx90635_read_ambient_raw(data->regmap, ambient_new_raw,
464 ambient_old_raw);
465 if (ret < 0)
466 goto read_unlock;
467
468 ret = mlx90635_read_object_raw(data->regmap, object_raw);
469 read_unlock:
470 mutex_unlock(&data->lock);
471 return ret;
472 }
473
mlx90635_preprocess_temp_amb(s16 ambient_new_raw,s16 ambient_old_raw,s16 Gb)474 static s64 mlx90635_preprocess_temp_amb(s16 ambient_new_raw,
475 s16 ambient_old_raw, s16 Gb)
476 {
477 s64 VR_Ta, kGb, tmp;
478
479 kGb = ((s64)Gb * 1000LL) >> 10ULL;
480 VR_Ta = (s64)ambient_old_raw * 1000000LL +
481 kGb * div64_s64(((s64)ambient_new_raw * 1000LL),
482 (MLX90635_PTAT_DIV));
483 tmp = div64_s64(
484 div64_s64(((s64)ambient_new_raw * 1000000000000LL),
485 (MLX90635_PTAT_DIV)), VR_Ta);
486 return div64_s64(tmp << 19ULL, 1000LL);
487 }
488
mlx90635_preprocess_temp_obj(s16 object_raw,s16 ambient_new_raw,s16 ambient_old_raw,s16 Gb)489 static s64 mlx90635_preprocess_temp_obj(s16 object_raw,
490 s16 ambient_new_raw,
491 s16 ambient_old_raw, s16 Gb)
492 {
493 s64 VR_IR, kGb, tmp;
494
495 kGb = ((s64)Gb * 1000LL) >> 10ULL;
496 VR_IR = (s64)ambient_old_raw * 1000000LL +
497 kGb * (div64_s64((s64)ambient_new_raw * 1000LL,
498 MLX90635_PTAT_DIV));
499 tmp = div64_s64(
500 div64_s64((s64)(object_raw * 1000000LL),
501 MLX90635_IR_DIV) * 1000000LL,
502 VR_IR);
503 return div64_s64((tmp << 19ULL), 1000LL);
504 }
505
mlx90635_calc_temp_ambient(s16 ambient_new_raw,s16 ambient_old_raw,u16 P_G,u16 P_O,s16 Gb)506 static s32 mlx90635_calc_temp_ambient(s16 ambient_new_raw, s16 ambient_old_raw,
507 u16 P_G, u16 P_O, s16 Gb)
508 {
509 s64 kPG, kPO, AMB;
510
511 AMB = mlx90635_preprocess_temp_amb(ambient_new_raw, ambient_old_raw,
512 Gb);
513 kPG = ((s64)P_G * 1000000LL) >> 9ULL;
514 kPO = AMB - (((s64)P_O * 1000LL) >> 1ULL);
515
516 return 30 * 1000LL + div64_s64(kPO * 1000000LL, kPG);
517 }
518
mlx90635_calc_temp_object_iteration(s32 prev_object_temp,s64 object,s64 TAdut,s64 TAdut4,s16 Ga,u32 Fa,u16 Fa_scale,s16 Fb,s16 Ha,s16 Hb,u16 emissivity)519 static s32 mlx90635_calc_temp_object_iteration(s32 prev_object_temp, s64 object,
520 s64 TAdut, s64 TAdut4, s16 Ga,
521 u32 Fa, u16 Fa_scale, s16 Fb,
522 s16 Ha, s16 Hb, u16 emissivity)
523 {
524 s64 calcedGa, calcedGb, calcedFa, Alpha_corr;
525 s64 Ha_customer, Hb_customer;
526
527 Ha_customer = ((s64)Ha * 1000000LL) >> 14ULL;
528 Hb_customer = ((s64)Hb * 100) >> 10ULL;
529
530 calcedGa = ((s64)((s64)Ga * (prev_object_temp - 35 * 1000LL)
531 * 1000LL)) >> 24LL;
532 calcedGb = ((s64)(Fb * (TAdut - 30 * 1000000LL))) >> 24LL;
533
534 Alpha_corr = ((s64)((s64)Fa * Ha_customer * 10000LL) >> Fa_scale);
535 Alpha_corr *= ((s64)(1 * 1000000LL + calcedGa + calcedGb));
536
537 Alpha_corr = div64_s64(Alpha_corr, 1000LL);
538 Alpha_corr *= emissivity;
539 Alpha_corr = div64_s64(Alpha_corr, 100LL);
540 calcedFa = div64_s64((s64)object * 100000000000LL, Alpha_corr);
541
542 return (int_sqrt64(int_sqrt64(calcedFa * 100000000LL + TAdut4))
543 - 27315 - Hb_customer) * 10;
544 }
545
mlx90635_calc_ta4(s64 TAdut,s64 scale)546 static s64 mlx90635_calc_ta4(s64 TAdut, s64 scale)
547 {
548 return (div64_s64(TAdut, scale) + 27315) *
549 (div64_s64(TAdut, scale) + 27315) *
550 (div64_s64(TAdut, scale) + 27315) *
551 (div64_s64(TAdut, scale) + 27315);
552 }
553
mlx90635_calc_temp_object(s64 object,s64 ambient,u32 Ea,u32 Eb,s16 Ga,u32 Fa,u16 Fa_scale,s16 Fb,s16 Ha,s16 Hb,u16 tmp_emi)554 static s32 mlx90635_calc_temp_object(s64 object, s64 ambient, u32 Ea, u32 Eb,
555 s16 Ga, u32 Fa, u16 Fa_scale, s16 Fb, s16 Ha, s16 Hb,
556 u16 tmp_emi)
557 {
558 s64 kTA, kTA0, TAdut, TAdut4;
559 s64 temp = 35000;
560 s8 i;
561
562 kTA = (Ea * 1000LL) >> 16LL;
563 kTA0 = (Eb * 1000LL) >> 8LL;
564 TAdut = div64_s64(((ambient - kTA0) * 1000000LL), kTA) + 30 * 1000000LL;
565 TAdut4 = mlx90635_calc_ta4(TAdut, 10000LL);
566
567 /* Iterations of calculation as described in datasheet */
568 for (i = 0; i < 5; ++i) {
569 temp = mlx90635_calc_temp_object_iteration(temp, object, TAdut, TAdut4,
570 Ga, Fa, Fa_scale, Fb, Ha, Hb,
571 tmp_emi);
572 }
573 return temp;
574 }
575
mlx90635_calc_object(struct mlx90635_data * data,int * val)576 static int mlx90635_calc_object(struct mlx90635_data *data, int *val)
577 {
578 s16 ambient_new_raw, ambient_old_raw, object_raw;
579 s16 Fb, Ga, Gb, Ha, Hb;
580 s64 object, ambient;
581 u32 Ea, Eb, Fa;
582 u16 Fa_scale;
583 int ret;
584
585 ret = mlx90635_read_ee_object(data->regmap_ee, &Ea, &Eb, &Fa, &Fb, &Ga, &Gb, &Ha, &Hb, &Fa_scale);
586 if (ret < 0)
587 return ret;
588
589 ret = mlx90635_read_all_channel(data,
590 &ambient_new_raw, &ambient_old_raw,
591 &object_raw);
592 if (ret < 0)
593 return ret;
594
595 ambient = mlx90635_preprocess_temp_amb(ambient_new_raw,
596 ambient_old_raw, Gb);
597 object = mlx90635_preprocess_temp_obj(object_raw,
598 ambient_new_raw,
599 ambient_old_raw, Gb);
600
601 *val = mlx90635_calc_temp_object(object, ambient, Ea, Eb, Ga, Fa, Fa_scale, Fb,
602 Ha, Hb, data->emissivity);
603 return 0;
604 }
605
mlx90635_calc_ambient(struct mlx90635_data * data,int * val)606 static int mlx90635_calc_ambient(struct mlx90635_data *data, int *val)
607 {
608 s16 ambient_new_raw, ambient_old_raw;
609 s16 PG, PO, Gb;
610 int ret;
611
612 ret = mlx90635_read_ee_ambient(data->regmap_ee, &PG, &PO, &Gb);
613 if (ret < 0)
614 return ret;
615
616 mutex_lock(&data->lock);
617 if (data->powerstatus == MLX90635_PWR_STATUS_SLEEP_STEP) {
618 ret = mlx90635_perform_measurement_burst(data);
619 if (ret < 0)
620 goto read_ambient_unlock;
621 }
622
623 ret = mlx90635_read_ambient_raw(data->regmap, &ambient_new_raw,
624 &ambient_old_raw);
625 read_ambient_unlock:
626 mutex_unlock(&data->lock);
627 if (ret < 0)
628 return ret;
629
630 *val = mlx90635_calc_temp_ambient(ambient_new_raw, ambient_old_raw,
631 PG, PO, Gb);
632 return ret;
633 }
634
mlx90635_get_refresh_rate(struct mlx90635_data * data,unsigned int * refresh_rate)635 static int mlx90635_get_refresh_rate(struct mlx90635_data *data,
636 unsigned int *refresh_rate)
637 {
638 unsigned int reg;
639 int ret;
640
641 ret = regmap_read(data->regmap, MLX90635_REG_CTRL1, ®);
642 if (ret < 0)
643 return ret;
644
645 *refresh_rate = FIELD_GET(MLX90635_CTRL1_REFRESH_RATE_MASK, reg);
646
647 return 0;
648 }
649
650 static const struct {
651 int val;
652 int val2;
653 } mlx90635_freqs[] = {
654 { 0, 200000 },
655 { 0, 500000 },
656 { 0, 900000 },
657 { 1, 700000 },
658 { 3, 0 },
659 { 4, 800000 },
660 { 6, 900000 },
661 { 8, 900000 }
662 };
663
664 /**
665 * mlx90635_pm_interaction_wakeup() - Measure time between user interactions to change powermode
666 * @data: pointer to mlx90635_data object containing interaction_ts information
667 *
668 * Switch to continuous mode when interaction is faster than MLX90635_MEAS_MAX_TIME. Update the
669 * interaction_ts for each function call with the jiffies to enable measurement between function
670 * calls. Initial value of the interaction_ts needs to be set before this function call.
671 */
mlx90635_pm_interaction_wakeup(struct mlx90635_data * data)672 static int mlx90635_pm_interaction_wakeup(struct mlx90635_data *data)
673 {
674 unsigned long now;
675 int ret;
676
677 now = jiffies;
678 if (time_in_range(now, data->interaction_ts,
679 data->interaction_ts +
680 msecs_to_jiffies(MLX90635_MEAS_MAX_TIME + 100))) {
681 ret = mlx90635_pwr_continuous(data);
682 if (ret < 0)
683 return ret;
684 }
685
686 data->interaction_ts = now;
687
688 return 0;
689 }
690
mlx90635_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * channel,int * val,int * val2,long mask)691 static int mlx90635_read_raw(struct iio_dev *indio_dev,
692 struct iio_chan_spec const *channel, int *val,
693 int *val2, long mask)
694 {
695 struct mlx90635_data *data = iio_priv(indio_dev);
696 int ret;
697 int cr;
698
699 pm_runtime_get_sync(&data->client->dev);
700 ret = mlx90635_pm_interaction_wakeup(data);
701 if (ret < 0)
702 goto mlx90635_read_raw_pm;
703
704 switch (mask) {
705 case IIO_CHAN_INFO_PROCESSED:
706 switch (channel->channel2) {
707 case IIO_MOD_TEMP_AMBIENT:
708 ret = mlx90635_calc_ambient(data, val);
709 if (ret < 0)
710 goto mlx90635_read_raw_pm;
711
712 ret = IIO_VAL_INT;
713 break;
714 case IIO_MOD_TEMP_OBJECT:
715 ret = mlx90635_calc_object(data, val);
716 if (ret < 0)
717 goto mlx90635_read_raw_pm;
718
719 ret = IIO_VAL_INT;
720 break;
721 default:
722 ret = -EINVAL;
723 break;
724 }
725 break;
726 case IIO_CHAN_INFO_CALIBEMISSIVITY:
727 if (data->emissivity == 1000) {
728 *val = 1;
729 *val2 = 0;
730 } else {
731 *val = 0;
732 *val2 = data->emissivity * 1000;
733 }
734 ret = IIO_VAL_INT_PLUS_MICRO;
735 break;
736 case IIO_CHAN_INFO_SAMP_FREQ:
737 ret = mlx90635_get_refresh_rate(data, &cr);
738 if (ret < 0)
739 goto mlx90635_read_raw_pm;
740
741 *val = mlx90635_freqs[cr].val;
742 *val2 = mlx90635_freqs[cr].val2;
743 ret = IIO_VAL_INT_PLUS_MICRO;
744 break;
745 default:
746 ret = -EINVAL;
747 break;
748 }
749
750 mlx90635_read_raw_pm:
751 pm_runtime_put_autosuspend(&data->client->dev);
752 return ret;
753 }
754
mlx90635_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * channel,int val,int val2,long mask)755 static int mlx90635_write_raw(struct iio_dev *indio_dev,
756 struct iio_chan_spec const *channel, int val,
757 int val2, long mask)
758 {
759 struct mlx90635_data *data = iio_priv(indio_dev);
760 int ret;
761 int i;
762
763 switch (mask) {
764 case IIO_CHAN_INFO_CALIBEMISSIVITY:
765 /* Confirm we are within 0 and 1.0 */
766 if (val < 0 || val2 < 0 || val > 1 ||
767 (val == 1 && val2 != 0))
768 return -EINVAL;
769 data->emissivity = val * 1000 + val2 / 1000;
770 return 0;
771 case IIO_CHAN_INFO_SAMP_FREQ:
772 for (i = 0; i < ARRAY_SIZE(mlx90635_freqs); i++) {
773 if (val == mlx90635_freqs[i].val &&
774 val2 == mlx90635_freqs[i].val2)
775 break;
776 }
777 if (i == ARRAY_SIZE(mlx90635_freqs))
778 return -EINVAL;
779
780 ret = regmap_write_bits(data->regmap, MLX90635_REG_CTRL1,
781 MLX90635_CTRL1_REFRESH_RATE_MASK, i);
782
783 return ret;
784 default:
785 return -EINVAL;
786 }
787 }
788
mlx90635_read_avail(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,const int ** vals,int * type,int * length,long mask)789 static int mlx90635_read_avail(struct iio_dev *indio_dev,
790 struct iio_chan_spec const *chan,
791 const int **vals, int *type, int *length,
792 long mask)
793 {
794 switch (mask) {
795 case IIO_CHAN_INFO_SAMP_FREQ:
796 *vals = (int *)mlx90635_freqs;
797 *type = IIO_VAL_INT_PLUS_MICRO;
798 *length = 2 * ARRAY_SIZE(mlx90635_freqs);
799 return IIO_AVAIL_LIST;
800 default:
801 return -EINVAL;
802 }
803 }
804
805 static const struct iio_chan_spec mlx90635_channels[] = {
806 {
807 .type = IIO_TEMP,
808 .modified = 1,
809 .channel2 = IIO_MOD_TEMP_AMBIENT,
810 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
811 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
812 .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),
813 },
814 {
815 .type = IIO_TEMP,
816 .modified = 1,
817 .channel2 = IIO_MOD_TEMP_OBJECT,
818 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
819 BIT(IIO_CHAN_INFO_CALIBEMISSIVITY),
820 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
821 .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),
822 },
823 };
824
825 static const struct iio_info mlx90635_info = {
826 .read_raw = mlx90635_read_raw,
827 .write_raw = mlx90635_write_raw,
828 .read_avail = mlx90635_read_avail,
829 };
830
mlx90635_sleep(void * _data)831 static void mlx90635_sleep(void *_data)
832 {
833 struct mlx90635_data *data = _data;
834
835 mlx90635_pwr_sleep_step(data);
836 }
837
mlx90635_suspend(struct mlx90635_data * data)838 static int mlx90635_suspend(struct mlx90635_data *data)
839 {
840 return mlx90635_pwr_sleep_step(data);
841 }
842
mlx90635_wakeup(struct mlx90635_data * data)843 static int mlx90635_wakeup(struct mlx90635_data *data)
844 {
845 s16 Fb, Ga, Gb, Ha, Hb, PG, PO;
846 unsigned int dsp_version;
847 u32 Ea, Eb, Fa;
848 u16 Fa_scale;
849 int ret;
850
851 regcache_cache_bypass(data->regmap_ee, false);
852 regcache_cache_only(data->regmap_ee, false);
853 regcache_cache_only(data->regmap, false);
854
855 ret = mlx90635_pwr_continuous(data);
856 if (ret < 0) {
857 dev_err(&data->client->dev, "Switch to continuous mode failed\n");
858 return ret;
859 }
860 ret = regmap_write_bits(data->regmap, MLX90635_REG_EE,
861 MLX90635_EE_ACTIVE, MLX90635_EE_ACTIVE);
862 if (ret < 0) {
863 dev_err(&data->client->dev, "Powering EEPROM failed\n");
864 return ret;
865 }
866 usleep_range(MLX90635_TIMING_EE_ACTIVE_MIN, MLX90635_TIMING_EE_ACTIVE_MAX);
867
868 regcache_mark_dirty(data->regmap_ee);
869
870 ret = regcache_sync(data->regmap_ee);
871 if (ret < 0) {
872 dev_err(&data->client->dev,
873 "Failed to sync cache: %d\n", ret);
874 return ret;
875 }
876
877 ret = mlx90635_read_ee_ambient(data->regmap_ee, &PG, &PO, &Gb);
878 if (ret < 0) {
879 dev_err(&data->client->dev,
880 "Failed to read to cache Ambient coefficients EEPROM region: %d\n", ret);
881 return ret;
882 }
883
884 ret = mlx90635_read_ee_object(data->regmap_ee, &Ea, &Eb, &Fa, &Fb, &Ga, &Gb, &Ha, &Hb, &Fa_scale);
885 if (ret < 0) {
886 dev_err(&data->client->dev,
887 "Failed to read to cache Object coefficients EEPROM region: %d\n", ret);
888 return ret;
889 }
890
891 ret = regmap_read(data->regmap_ee, MLX90635_EE_VERSION, &dsp_version);
892 if (ret < 0) {
893 dev_err(&data->client->dev,
894 "Failed to read to cache of EEPROM version: %d\n", ret);
895 return ret;
896 }
897
898 regcache_cache_only(data->regmap_ee, true);
899
900 return ret;
901 }
902
mlx90635_disable_regulator(void * _data)903 static void mlx90635_disable_regulator(void *_data)
904 {
905 struct mlx90635_data *data = _data;
906 int ret;
907
908 ret = regulator_disable(data->regulator);
909 if (ret < 0)
910 dev_err(regmap_get_device(data->regmap),
911 "Failed to disable power regulator: %d\n", ret);
912 }
913
mlx90635_enable_regulator(struct mlx90635_data * data)914 static int mlx90635_enable_regulator(struct mlx90635_data *data)
915 {
916 int ret;
917
918 ret = regulator_enable(data->regulator);
919 if (ret < 0) {
920 dev_err(regmap_get_device(data->regmap), "Failed to enable power regulator!\n");
921 return ret;
922 }
923
924 mlx90635_reset_delay();
925
926 return ret;
927 }
928
mlx90635_probe(struct i2c_client * client)929 static int mlx90635_probe(struct i2c_client *client)
930 {
931 struct mlx90635_data *mlx90635;
932 struct iio_dev *indio_dev;
933 unsigned int dsp_version;
934 struct regmap *regmap;
935 struct regmap *regmap_ee;
936 int ret;
937
938 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*mlx90635));
939 if (!indio_dev)
940 return -ENOMEM;
941
942 regmap = devm_regmap_init_i2c(client, &mlx90635_regmap);
943 if (IS_ERR(regmap))
944 return dev_err_probe(&client->dev, PTR_ERR(regmap),
945 "failed to allocate regmap\n");
946
947 regmap_ee = devm_regmap_init_i2c(client, &mlx90635_regmap_ee);
948 if (IS_ERR(regmap_ee))
949 return dev_err_probe(&client->dev, PTR_ERR(regmap_ee),
950 "failed to allocate EEPROM regmap\n");
951
952 mlx90635 = iio_priv(indio_dev);
953 i2c_set_clientdata(client, indio_dev);
954 mlx90635->client = client;
955 mlx90635->regmap = regmap;
956 mlx90635->regmap_ee = regmap_ee;
957 mlx90635->powerstatus = MLX90635_PWR_STATUS_SLEEP_STEP;
958
959 mutex_init(&mlx90635->lock);
960 indio_dev->name = "mlx90635";
961 indio_dev->modes = INDIO_DIRECT_MODE;
962 indio_dev->info = &mlx90635_info;
963 indio_dev->channels = mlx90635_channels;
964 indio_dev->num_channels = ARRAY_SIZE(mlx90635_channels);
965
966 mlx90635->regulator = devm_regulator_get(&client->dev, "vdd");
967 if (IS_ERR(mlx90635->regulator))
968 return dev_err_probe(&client->dev, PTR_ERR(mlx90635->regulator),
969 "failed to get vdd regulator");
970
971 ret = mlx90635_enable_regulator(mlx90635);
972 if (ret < 0)
973 return ret;
974
975 ret = devm_add_action_or_reset(&client->dev, mlx90635_disable_regulator,
976 mlx90635);
977 if (ret < 0)
978 return ret;
979
980 ret = mlx90635_wakeup(mlx90635);
981 if (ret < 0)
982 return dev_err_probe(&client->dev, ret, "wakeup failed\n");
983
984 ret = devm_add_action_or_reset(&client->dev, mlx90635_sleep, mlx90635);
985 if (ret < 0)
986 return ret;
987
988 ret = regmap_read(mlx90635->regmap_ee, MLX90635_EE_VERSION, &dsp_version);
989 if (ret < 0)
990 return dev_err_probe(&client->dev, ret, "read of version failed\n");
991
992 dsp_version = dsp_version & MLX90635_VERSION_MASK;
993
994 if (FIELD_GET(MLX90635_DSP_FIXED, dsp_version)) {
995 if (MLX90635_DSP_VERSION(dsp_version) == MLX90635_ID_DSPv1) {
996 dev_dbg(&client->dev,
997 "Detected DSP v1 calibration %x\n", dsp_version);
998 } else {
999 dev_dbg(&client->dev,
1000 "Detected Unknown EEPROM calibration %lx\n",
1001 MLX90635_DSP_VERSION(dsp_version));
1002 }
1003 } else {
1004 return dev_err_probe(&client->dev, -EPROTONOSUPPORT,
1005 "Wrong fixed top bit %x (expected 0x8X0X)\n",
1006 dsp_version);
1007 }
1008
1009 mlx90635->emissivity = 1000;
1010 mlx90635->interaction_ts = jiffies; /* Set initial value */
1011
1012 pm_runtime_get_noresume(&client->dev);
1013 pm_runtime_set_active(&client->dev);
1014
1015 ret = devm_pm_runtime_enable(&client->dev);
1016 if (ret)
1017 return dev_err_probe(&client->dev, ret,
1018 "failed to enable powermanagement\n");
1019
1020 pm_runtime_set_autosuspend_delay(&client->dev, MLX90635_SLEEP_DELAY_MS);
1021 pm_runtime_use_autosuspend(&client->dev);
1022 pm_runtime_put_autosuspend(&client->dev);
1023
1024 return devm_iio_device_register(&client->dev, indio_dev);
1025 }
1026
1027 static const struct i2c_device_id mlx90635_id[] = {
1028 { .name = "mlx90635" },
1029 { }
1030 };
1031 MODULE_DEVICE_TABLE(i2c, mlx90635_id);
1032
1033 static const struct of_device_id mlx90635_of_match[] = {
1034 { .compatible = "melexis,mlx90635" },
1035 { }
1036 };
1037 MODULE_DEVICE_TABLE(of, mlx90635_of_match);
1038
mlx90635_pm_suspend(struct device * dev)1039 static int mlx90635_pm_suspend(struct device *dev)
1040 {
1041 struct mlx90635_data *data = iio_priv(dev_get_drvdata(dev));
1042 int ret;
1043
1044 ret = mlx90635_suspend(data);
1045 if (ret < 0)
1046 return ret;
1047
1048 ret = regulator_disable(data->regulator);
1049 if (ret < 0)
1050 dev_err(regmap_get_device(data->regmap),
1051 "Failed to disable power regulator: %d\n", ret);
1052
1053 return ret;
1054 }
1055
mlx90635_pm_resume(struct device * dev)1056 static int mlx90635_pm_resume(struct device *dev)
1057 {
1058 struct mlx90635_data *data = iio_priv(dev_get_drvdata(dev));
1059 int ret;
1060
1061 ret = mlx90635_enable_regulator(data);
1062 if (ret < 0)
1063 return ret;
1064
1065 return mlx90635_wakeup(data);
1066 }
1067
mlx90635_pm_runtime_suspend(struct device * dev)1068 static int mlx90635_pm_runtime_suspend(struct device *dev)
1069 {
1070 struct mlx90635_data *data = iio_priv(dev_get_drvdata(dev));
1071
1072 return mlx90635_pwr_sleep_step(data);
1073 }
1074
1075 static const struct dev_pm_ops mlx90635_pm_ops = {
1076 SYSTEM_SLEEP_PM_OPS(mlx90635_pm_suspend, mlx90635_pm_resume)
1077 RUNTIME_PM_OPS(mlx90635_pm_runtime_suspend, NULL, NULL)
1078 };
1079
1080 static struct i2c_driver mlx90635_driver = {
1081 .driver = {
1082 .name = "mlx90635",
1083 .of_match_table = mlx90635_of_match,
1084 .pm = pm_ptr(&mlx90635_pm_ops),
1085 },
1086 .probe = mlx90635_probe,
1087 .id_table = mlx90635_id,
1088 };
1089 module_i2c_driver(mlx90635_driver);
1090
1091 MODULE_AUTHOR("Crt Mori <cmo@melexis.com>");
1092 MODULE_DESCRIPTION("Melexis MLX90635 contactless Infra Red temperature sensor driver");
1093 MODULE_LICENSE("GPL");
1094