1 // SPDX-License-Identifier: GPL-2.0
3 * Analog Devices LTC2983 Multi-Sensor Digital Temperature Measurement System
6 * Copyright 2019 Analog Devices Inc.
8 #include <linux/bitfield.h>
9 #include <linux/completion.h>
10 #include <linux/device.h>
11 #include <linux/kernel.h>
12 #include <linux/iio/iio.h>
13 #include <linux/interrupt.h>
14 #include <linux/list.h>
15 #include <linux/module.h>
16 #include <linux/of_gpio.h>
17 #include <linux/regmap.h>
18 #include <linux/spi/spi.h>
21 #define LTC2983_STATUS_REG 0x0000
22 #define LTC2983_TEMP_RES_START_REG 0x0010
23 #define LTC2983_TEMP_RES_END_REG 0x005F
24 #define LTC2983_GLOBAL_CONFIG_REG 0x00F0
25 #define LTC2983_MULT_CHANNEL_START_REG 0x00F4
26 #define LTC2983_MULT_CHANNEL_END_REG 0x00F7
27 #define LTC2983_MUX_CONFIG_REG 0x00FF
28 #define LTC2983_CHAN_ASSIGN_START_REG 0x0200
29 #define LTC2983_CHAN_ASSIGN_END_REG 0x024F
30 #define LTC2983_CUST_SENS_TBL_START_REG 0x0250
31 #define LTC2983_CUST_SENS_TBL_END_REG 0x03CF
33 #define LTC2983_DIFFERENTIAL_CHAN_MIN 2
34 #define LTC2983_MAX_CHANNELS_NR 20
35 #define LTC2983_MIN_CHANNELS_NR 1
36 #define LTC2983_SLEEP 0x97
37 #define LTC2983_CUSTOM_STEINHART_SIZE 24
38 #define LTC2983_CUSTOM_SENSOR_ENTRY_SZ 6
39 #define LTC2983_CUSTOM_STEINHART_ENTRY_SZ 4
41 #define LTC2983_CHAN_START_ADDR(chan) \
42 (((chan - 1) * 4) + LTC2983_CHAN_ASSIGN_START_REG)
43 #define LTC2983_CHAN_RES_ADDR(chan) \
44 (((chan - 1) * 4) + LTC2983_TEMP_RES_START_REG)
45 #define LTC2983_THERMOCOUPLE_DIFF_MASK BIT(3)
46 #define LTC2983_THERMOCOUPLE_SGL(x) \
47 FIELD_PREP(LTC2983_THERMOCOUPLE_DIFF_MASK, x)
48 #define LTC2983_THERMOCOUPLE_OC_CURR_MASK GENMASK(1, 0)
49 #define LTC2983_THERMOCOUPLE_OC_CURR(x) \
50 FIELD_PREP(LTC2983_THERMOCOUPLE_OC_CURR_MASK, x)
51 #define LTC2983_THERMOCOUPLE_OC_CHECK_MASK BIT(2)
52 #define LTC2983_THERMOCOUPLE_OC_CHECK(x) \
53 FIELD_PREP(LTC2983_THERMOCOUPLE_OC_CHECK_MASK, x)
55 #define LTC2983_THERMISTOR_DIFF_MASK BIT(2)
56 #define LTC2983_THERMISTOR_SGL(x) \
57 FIELD_PREP(LTC2983_THERMISTOR_DIFF_MASK, x)
58 #define LTC2983_THERMISTOR_R_SHARE_MASK BIT(1)
59 #define LTC2983_THERMISTOR_R_SHARE(x) \
60 FIELD_PREP(LTC2983_THERMISTOR_R_SHARE_MASK, x)
61 #define LTC2983_THERMISTOR_C_ROTATE_MASK BIT(0)
62 #define LTC2983_THERMISTOR_C_ROTATE(x) \
63 FIELD_PREP(LTC2983_THERMISTOR_C_ROTATE_MASK, x)
65 #define LTC2983_DIODE_DIFF_MASK BIT(2)
66 #define LTC2983_DIODE_SGL(x) \
67 FIELD_PREP(LTC2983_DIODE_DIFF_MASK, x)
68 #define LTC2983_DIODE_3_CONV_CYCLE_MASK BIT(1)
69 #define LTC2983_DIODE_3_CONV_CYCLE(x) \
70 FIELD_PREP(LTC2983_DIODE_3_CONV_CYCLE_MASK, x)
71 #define LTC2983_DIODE_AVERAGE_ON_MASK BIT(0)
72 #define LTC2983_DIODE_AVERAGE_ON(x) \
73 FIELD_PREP(LTC2983_DIODE_AVERAGE_ON_MASK, x)
75 #define LTC2983_RTD_4_WIRE_MASK BIT(3)
76 #define LTC2983_RTD_ROTATION_MASK BIT(1)
77 #define LTC2983_RTD_C_ROTATE(x) \
78 FIELD_PREP(LTC2983_RTD_ROTATION_MASK, x)
79 #define LTC2983_RTD_KELVIN_R_SENSE_MASK GENMASK(3, 2)
80 #define LTC2983_RTD_N_WIRES_MASK GENMASK(3, 2)
81 #define LTC2983_RTD_N_WIRES(x) \
82 FIELD_PREP(LTC2983_RTD_N_WIRES_MASK, x)
83 #define LTC2983_RTD_R_SHARE_MASK BIT(0)
84 #define LTC2983_RTD_R_SHARE(x) \
85 FIELD_PREP(LTC2983_RTD_R_SHARE_MASK, 1)
87 #define LTC2983_COMMON_HARD_FAULT_MASK GENMASK(31, 30)
88 #define LTC2983_COMMON_SOFT_FAULT_MASK GENMASK(27, 25)
90 #define LTC2983_STATUS_START_MASK BIT(7)
91 #define LTC2983_STATUS_START(x) FIELD_PREP(LTC2983_STATUS_START_MASK, x)
93 #define LTC2983_STATUS_CHAN_SEL_MASK GENMASK(4, 0)
94 #define LTC2983_STATUS_CHAN_SEL(x) \
95 FIELD_PREP(LTC2983_STATUS_CHAN_SEL_MASK, x)
97 #define LTC2983_TEMP_UNITS_MASK BIT(2)
98 #define LTC2983_TEMP_UNITS(x) FIELD_PREP(LTC2983_TEMP_UNITS_MASK, x)
100 #define LTC2983_NOTCH_FREQ_MASK GENMASK(1, 0)
101 #define LTC2983_NOTCH_FREQ(x) FIELD_PREP(LTC2983_NOTCH_FREQ_MASK, x)
103 #define LTC2983_RES_VALID_MASK BIT(24)
104 #define LTC2983_DATA_MASK GENMASK(23, 0)
105 #define LTC2983_DATA_SIGN_BIT 23
107 #define LTC2983_CHAN_TYPE_MASK GENMASK(31, 27)
108 #define LTC2983_CHAN_TYPE(x) FIELD_PREP(LTC2983_CHAN_TYPE_MASK, x)
110 /* cold junction for thermocouples and rsense for rtd's and thermistor's */
111 #define LTC2983_CHAN_ASSIGN_MASK GENMASK(26, 22)
112 #define LTC2983_CHAN_ASSIGN(x) FIELD_PREP(LTC2983_CHAN_ASSIGN_MASK, x)
114 #define LTC2983_CUSTOM_LEN_MASK GENMASK(5, 0)
115 #define LTC2983_CUSTOM_LEN(x) FIELD_PREP(LTC2983_CUSTOM_LEN_MASK, x)
117 #define LTC2983_CUSTOM_ADDR_MASK GENMASK(11, 6)
118 #define LTC2983_CUSTOM_ADDR(x) FIELD_PREP(LTC2983_CUSTOM_ADDR_MASK, x)
120 #define LTC2983_THERMOCOUPLE_CFG_MASK GENMASK(21, 18)
121 #define LTC2983_THERMOCOUPLE_CFG(x) \
122 FIELD_PREP(LTC2983_THERMOCOUPLE_CFG_MASK, x)
123 #define LTC2983_THERMOCOUPLE_HARD_FAULT_MASK GENMASK(31, 29)
124 #define LTC2983_THERMOCOUPLE_SOFT_FAULT_MASK GENMASK(28, 25)
126 #define LTC2983_RTD_CFG_MASK GENMASK(21, 18)
127 #define LTC2983_RTD_CFG(x) FIELD_PREP(LTC2983_RTD_CFG_MASK, x)
128 #define LTC2983_RTD_EXC_CURRENT_MASK GENMASK(17, 14)
129 #define LTC2983_RTD_EXC_CURRENT(x) \
130 FIELD_PREP(LTC2983_RTD_EXC_CURRENT_MASK, x)
131 #define LTC2983_RTD_CURVE_MASK GENMASK(13, 12)
132 #define LTC2983_RTD_CURVE(x) FIELD_PREP(LTC2983_RTD_CURVE_MASK, x)
134 #define LTC2983_THERMISTOR_CFG_MASK GENMASK(21, 19)
135 #define LTC2983_THERMISTOR_CFG(x) \
136 FIELD_PREP(LTC2983_THERMISTOR_CFG_MASK, x)
137 #define LTC2983_THERMISTOR_EXC_CURRENT_MASK GENMASK(18, 15)
138 #define LTC2983_THERMISTOR_EXC_CURRENT(x) \
139 FIELD_PREP(LTC2983_THERMISTOR_EXC_CURRENT_MASK, x)
141 #define LTC2983_DIODE_CFG_MASK GENMASK(26, 24)
142 #define LTC2983_DIODE_CFG(x) FIELD_PREP(LTC2983_DIODE_CFG_MASK, x)
143 #define LTC2983_DIODE_EXC_CURRENT_MASK GENMASK(23, 22)
144 #define LTC2983_DIODE_EXC_CURRENT(x) \
145 FIELD_PREP(LTC2983_DIODE_EXC_CURRENT_MASK, x)
146 #define LTC2983_DIODE_IDEAL_FACTOR_MASK GENMASK(21, 0)
147 #define LTC2983_DIODE_IDEAL_FACTOR(x) \
148 FIELD_PREP(LTC2983_DIODE_IDEAL_FACTOR_MASK, x)
150 #define LTC2983_R_SENSE_VAL_MASK GENMASK(26, 0)
151 #define LTC2983_R_SENSE_VAL(x) FIELD_PREP(LTC2983_R_SENSE_VAL_MASK, x)
153 #define LTC2983_ADC_SINGLE_ENDED_MASK BIT(26)
154 #define LTC2983_ADC_SINGLE_ENDED(x) \
155 FIELD_PREP(LTC2983_ADC_SINGLE_ENDED_MASK, x)
158 LTC2983_SENSOR_THERMOCOUPLE = 1,
159 LTC2983_SENSOR_THERMOCOUPLE_CUSTOM = 9,
160 LTC2983_SENSOR_RTD = 10,
161 LTC2983_SENSOR_RTD_CUSTOM = 18,
162 LTC2983_SENSOR_THERMISTOR = 19,
163 LTC2983_SENSOR_THERMISTOR_STEINHART = 26,
164 LTC2983_SENSOR_THERMISTOR_CUSTOM = 27,
165 LTC2983_SENSOR_DIODE = 28,
166 LTC2983_SENSOR_SENSE_RESISTOR = 29,
167 LTC2983_SENSOR_DIRECT_ADC = 30,
170 #define to_thermocouple(_sensor) \
171 container_of(_sensor, struct ltc2983_thermocouple, sensor)
173 #define to_rtd(_sensor) \
174 container_of(_sensor, struct ltc2983_rtd, sensor)
176 #define to_thermistor(_sensor) \
177 container_of(_sensor, struct ltc2983_thermistor, sensor)
179 #define to_diode(_sensor) \
180 container_of(_sensor, struct ltc2983_diode, sensor)
182 #define to_rsense(_sensor) \
183 container_of(_sensor, struct ltc2983_rsense, sensor)
185 #define to_adc(_sensor) \
186 container_of(_sensor, struct ltc2983_adc, sensor)
188 struct ltc2983_data {
189 struct regmap *regmap;
190 struct spi_device *spi;
192 struct completion completion;
193 struct iio_chan_spec *iio_chan;
194 struct ltc2983_sensor **sensors;
195 u32 mux_delay_config;
196 u32 filter_notch_freq;
197 u16 custom_table_size;
201 * DMA (thus cache coherency maintenance) requires the
202 * transfer buffers to live in their own cache lines.
203 * Holds the converted temperature
205 __be32 temp ____cacheline_aligned;
208 struct ltc2983_sensor {
209 int (*fault_handler)(const struct ltc2983_data *st, const u32 result);
210 int (*assign_chan)(struct ltc2983_data *st,
211 const struct ltc2983_sensor *sensor);
212 /* specifies the sensor channel */
218 struct ltc2983_custom_sensor {
219 /* raw table sensor data */
227 struct ltc2983_thermocouple {
228 struct ltc2983_sensor sensor;
229 struct ltc2983_custom_sensor *custom;
231 u32 cold_junction_chan;
235 struct ltc2983_sensor sensor;
236 struct ltc2983_custom_sensor *custom;
239 u32 excitation_current;
243 struct ltc2983_thermistor {
244 struct ltc2983_sensor sensor;
245 struct ltc2983_custom_sensor *custom;
248 u32 excitation_current;
251 struct ltc2983_diode {
252 struct ltc2983_sensor sensor;
254 u32 excitation_current;
255 u32 ideal_factor_value;
258 struct ltc2983_rsense {
259 struct ltc2983_sensor sensor;
264 struct ltc2983_sensor sensor;
269 * Convert to Q format numbers. These number's are integers where
270 * the number of integer and fractional bits are specified. The resolution
271 * is given by 1/@resolution and tell us the number of fractional bits. For
272 * instance a resolution of 2^-10 means we have 10 fractional bits.
274 static u32 __convert_to_raw(const u64 val, const u32 resolution)
276 u64 __res = val * resolution;
278 /* all values are multiplied by 1000000 to remove the fraction */
279 do_div(__res, 1000000);
284 static u32 __convert_to_raw_sign(const u64 val, const u32 resolution)
286 s64 __res = -(s32)val;
288 __res = __convert_to_raw(__res, resolution);
293 static int __ltc2983_fault_handler(const struct ltc2983_data *st,
294 const u32 result, const u32 hard_mask,
297 const struct device *dev = &st->spi->dev;
299 if (result & hard_mask) {
300 dev_err(dev, "Invalid conversion: Sensor HARD fault\n");
302 } else if (result & soft_mask) {
303 /* just print a warning */
304 dev_warn(dev, "Suspicious conversion: Sensor SOFT fault\n");
310 static int __ltc2983_chan_assign_common(const struct ltc2983_data *st,
311 const struct ltc2983_sensor *sensor,
314 u32 reg = LTC2983_CHAN_START_ADDR(sensor->chan);
317 chan_val |= LTC2983_CHAN_TYPE(sensor->type);
318 dev_dbg(&st->spi->dev, "Assign reg:0x%04X, val:0x%08X\n", reg,
320 __chan_val = cpu_to_be32(chan_val);
321 return regmap_bulk_write(st->regmap, reg, &__chan_val,
325 static int __ltc2983_chan_custom_sensor_assign(struct ltc2983_data *st,
326 struct ltc2983_custom_sensor *custom,
330 u8 mult = custom->is_steinhart ? LTC2983_CUSTOM_STEINHART_ENTRY_SZ :
331 LTC2983_CUSTOM_SENSOR_ENTRY_SZ;
332 const struct device *dev = &st->spi->dev;
334 * custom->size holds the raw size of the table. However, when
335 * configuring the sensor channel, we must write the number of
336 * entries of the table minus 1. For steinhart sensors 0 is written
337 * since the size is constant!
339 const u8 len = custom->is_steinhart ? 0 :
340 (custom->size / LTC2983_CUSTOM_SENSOR_ENTRY_SZ) - 1;
342 * Check if the offset was assigned already. It should be for steinhart
343 * sensors. When coming from sleep, it should be assigned for all.
345 if (custom->offset < 0) {
347 * This needs to be done again here because, from the moment
348 * when this test was done (successfully) for this custom
349 * sensor, a steinhart sensor might have been added changing
350 * custom_table_size...
352 if (st->custom_table_size + custom->size >
353 (LTC2983_CUST_SENS_TBL_END_REG -
354 LTC2983_CUST_SENS_TBL_START_REG) + 1) {
356 "Not space left(%d) for new custom sensor(%zu)",
357 st->custom_table_size,
362 custom->offset = st->custom_table_size /
363 LTC2983_CUSTOM_SENSOR_ENTRY_SZ;
364 st->custom_table_size += custom->size;
367 reg = (custom->offset * mult) + LTC2983_CUST_SENS_TBL_START_REG;
369 *chan_val |= LTC2983_CUSTOM_LEN(len);
370 *chan_val |= LTC2983_CUSTOM_ADDR(custom->offset);
371 dev_dbg(dev, "Assign custom sensor, reg:0x%04X, off:%d, sz:%zu",
374 /* write custom sensor table */
375 return regmap_bulk_write(st->regmap, reg, custom->table, custom->size);
378 static struct ltc2983_custom_sensor *__ltc2983_custom_sensor_new(
379 struct ltc2983_data *st,
380 const struct device_node *np,
381 const char *propname,
382 const bool is_steinhart,
383 const u32 resolution,
384 const bool has_signed)
386 struct ltc2983_custom_sensor *new_custom;
387 u8 index, n_entries, tbl = 0;
388 struct device *dev = &st->spi->dev;
390 * For custom steinhart, the full u32 is taken. For all the others
391 * the MSB is discarded.
393 const u8 n_size = (is_steinhart == true) ? 4 : 3;
394 const u8 e_size = (is_steinhart == true) ? sizeof(u32) : sizeof(u64);
396 n_entries = of_property_count_elems_of_size(np, propname, e_size);
397 /* n_entries must be an even number */
398 if (!n_entries || (n_entries % 2) != 0) {
399 dev_err(dev, "Number of entries either 0 or not even\n");
400 return ERR_PTR(-EINVAL);
403 new_custom = devm_kzalloc(dev, sizeof(*new_custom), GFP_KERNEL);
405 return ERR_PTR(-ENOMEM);
407 new_custom->size = n_entries * n_size;
408 /* check Steinhart size */
409 if (is_steinhart && new_custom->size != LTC2983_CUSTOM_STEINHART_SIZE) {
410 dev_err(dev, "Steinhart sensors size(%zu) must be 24",
412 return ERR_PTR(-EINVAL);
414 /* Check space on the table. */
415 if (st->custom_table_size + new_custom->size >
416 (LTC2983_CUST_SENS_TBL_END_REG -
417 LTC2983_CUST_SENS_TBL_START_REG) + 1) {
418 dev_err(dev, "No space left(%d) for new custom sensor(%zu)",
419 st->custom_table_size, new_custom->size);
420 return ERR_PTR(-EINVAL);
423 /* allocate the table */
424 new_custom->table = devm_kzalloc(dev, new_custom->size, GFP_KERNEL);
425 if (!new_custom->table)
426 return ERR_PTR(-ENOMEM);
428 for (index = 0; index < n_entries; index++) {
431 * Steinhart sensors are configured with raw values in the
432 * devicetree. For the other sensors we must convert the
433 * value to raw. The odd index's correspond to temperarures
434 * and always have 1/1024 of resolution. Temperatures also
435 * come in kelvin, so signed values is not possible
438 of_property_read_u64_index(np, propname, index, &temp);
440 if ((index % 2) != 0)
441 temp = __convert_to_raw(temp, 1024);
442 else if (has_signed && (s64)temp < 0)
443 temp = __convert_to_raw_sign(temp, resolution);
445 temp = __convert_to_raw(temp, resolution);
449 of_property_read_u32_index(np, propname, index, &t32);
453 for (j = 0; j < n_size; j++)
454 new_custom->table[tbl++] =
455 temp >> (8 * (n_size - j - 1));
458 new_custom->is_steinhart = is_steinhart;
460 * This is done to first add all the steinhart sensors to the table,
461 * in order to maximize the table usage. If we mix adding steinhart
462 * with the other sensors, we might have to do some roundup to make
463 * sure that sensor_addr - 0x250(start address) is a multiple of 4
464 * (for steinhart), and a multiple of 6 for all the other sensors.
465 * Since we have const 24 bytes for steinhart sensors and 24 is
466 * also a multiple of 6, we guarantee that the first non-steinhart
467 * sensor will sit in a correct address without the need of filling
471 new_custom->offset = st->custom_table_size /
472 LTC2983_CUSTOM_STEINHART_ENTRY_SZ;
473 st->custom_table_size += new_custom->size;
475 /* mark as unset. This is checked later on the assign phase */
476 new_custom->offset = -1;
482 static int ltc2983_thermocouple_fault_handler(const struct ltc2983_data *st,
485 return __ltc2983_fault_handler(st, result,
486 LTC2983_THERMOCOUPLE_HARD_FAULT_MASK,
487 LTC2983_THERMOCOUPLE_SOFT_FAULT_MASK);
490 static int ltc2983_common_fault_handler(const struct ltc2983_data *st,
493 return __ltc2983_fault_handler(st, result,
494 LTC2983_COMMON_HARD_FAULT_MASK,
495 LTC2983_COMMON_SOFT_FAULT_MASK);
498 static int ltc2983_thermocouple_assign_chan(struct ltc2983_data *st,
499 const struct ltc2983_sensor *sensor)
501 struct ltc2983_thermocouple *thermo = to_thermocouple(sensor);
504 chan_val = LTC2983_CHAN_ASSIGN(thermo->cold_junction_chan);
505 chan_val |= LTC2983_THERMOCOUPLE_CFG(thermo->sensor_config);
507 if (thermo->custom) {
510 ret = __ltc2983_chan_custom_sensor_assign(st, thermo->custom,
515 return __ltc2983_chan_assign_common(st, sensor, chan_val);
518 static int ltc2983_rtd_assign_chan(struct ltc2983_data *st,
519 const struct ltc2983_sensor *sensor)
521 struct ltc2983_rtd *rtd = to_rtd(sensor);
524 chan_val = LTC2983_CHAN_ASSIGN(rtd->r_sense_chan);
525 chan_val |= LTC2983_RTD_CFG(rtd->sensor_config);
526 chan_val |= LTC2983_RTD_EXC_CURRENT(rtd->excitation_current);
527 chan_val |= LTC2983_RTD_CURVE(rtd->rtd_curve);
532 ret = __ltc2983_chan_custom_sensor_assign(st, rtd->custom,
537 return __ltc2983_chan_assign_common(st, sensor, chan_val);
540 static int ltc2983_thermistor_assign_chan(struct ltc2983_data *st,
541 const struct ltc2983_sensor *sensor)
543 struct ltc2983_thermistor *thermistor = to_thermistor(sensor);
546 chan_val = LTC2983_CHAN_ASSIGN(thermistor->r_sense_chan);
547 chan_val |= LTC2983_THERMISTOR_CFG(thermistor->sensor_config);
549 LTC2983_THERMISTOR_EXC_CURRENT(thermistor->excitation_current);
551 if (thermistor->custom) {
554 ret = __ltc2983_chan_custom_sensor_assign(st,
560 return __ltc2983_chan_assign_common(st, sensor, chan_val);
563 static int ltc2983_diode_assign_chan(struct ltc2983_data *st,
564 const struct ltc2983_sensor *sensor)
566 struct ltc2983_diode *diode = to_diode(sensor);
569 chan_val = LTC2983_DIODE_CFG(diode->sensor_config);
570 chan_val |= LTC2983_DIODE_EXC_CURRENT(diode->excitation_current);
571 chan_val |= LTC2983_DIODE_IDEAL_FACTOR(diode->ideal_factor_value);
573 return __ltc2983_chan_assign_common(st, sensor, chan_val);
576 static int ltc2983_r_sense_assign_chan(struct ltc2983_data *st,
577 const struct ltc2983_sensor *sensor)
579 struct ltc2983_rsense *rsense = to_rsense(sensor);
582 chan_val = LTC2983_R_SENSE_VAL(rsense->r_sense_val);
584 return __ltc2983_chan_assign_common(st, sensor, chan_val);
587 static int ltc2983_adc_assign_chan(struct ltc2983_data *st,
588 const struct ltc2983_sensor *sensor)
590 struct ltc2983_adc *adc = to_adc(sensor);
593 chan_val = LTC2983_ADC_SINGLE_ENDED(adc->single_ended);
595 return __ltc2983_chan_assign_common(st, sensor, chan_val);
598 static struct ltc2983_sensor *ltc2983_thermocouple_new(
599 const struct device_node *child,
600 struct ltc2983_data *st,
601 const struct ltc2983_sensor *sensor)
603 struct ltc2983_thermocouple *thermo;
604 struct device_node *phandle;
608 thermo = devm_kzalloc(&st->spi->dev, sizeof(*thermo), GFP_KERNEL);
610 return ERR_PTR(-ENOMEM);
612 if (of_property_read_bool(child, "adi,single-ended"))
613 thermo->sensor_config = LTC2983_THERMOCOUPLE_SGL(1);
615 ret = of_property_read_u32(child, "adi,sensor-oc-current-microamp",
618 switch (oc_current) {
620 thermo->sensor_config |=
621 LTC2983_THERMOCOUPLE_OC_CURR(0);
624 thermo->sensor_config |=
625 LTC2983_THERMOCOUPLE_OC_CURR(1);
628 thermo->sensor_config |=
629 LTC2983_THERMOCOUPLE_OC_CURR(2);
632 thermo->sensor_config |=
633 LTC2983_THERMOCOUPLE_OC_CURR(3);
636 dev_err(&st->spi->dev,
637 "Invalid open circuit current:%u", oc_current);
638 return ERR_PTR(-EINVAL);
641 thermo->sensor_config |= LTC2983_THERMOCOUPLE_OC_CHECK(1);
643 /* validate channel index */
644 if (!(thermo->sensor_config & LTC2983_THERMOCOUPLE_DIFF_MASK) &&
645 sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
646 dev_err(&st->spi->dev,
647 "Invalid chann:%d for differential thermocouple",
649 return ERR_PTR(-EINVAL);
652 phandle = of_parse_phandle(child, "adi,cold-junction-handle", 0);
656 ret = of_property_read_u32(phandle, "reg",
657 &thermo->cold_junction_chan);
660 * This would be catched later but we can just return
661 * the error right away.
663 dev_err(&st->spi->dev, "Property reg must be given\n");
664 of_node_put(phandle);
665 return ERR_PTR(-EINVAL);
669 /* check custom sensor */
670 if (sensor->type == LTC2983_SENSOR_THERMOCOUPLE_CUSTOM) {
671 const char *propname = "adi,custom-thermocouple";
673 thermo->custom = __ltc2983_custom_sensor_new(st, child,
676 if (IS_ERR(thermo->custom)) {
677 of_node_put(phandle);
678 return ERR_CAST(thermo->custom);
682 /* set common parameters */
683 thermo->sensor.fault_handler = ltc2983_thermocouple_fault_handler;
684 thermo->sensor.assign_chan = ltc2983_thermocouple_assign_chan;
686 of_node_put(phandle);
687 return &thermo->sensor;
690 static struct ltc2983_sensor *ltc2983_rtd_new(const struct device_node *child,
691 struct ltc2983_data *st,
692 const struct ltc2983_sensor *sensor)
694 struct ltc2983_rtd *rtd;
696 struct device *dev = &st->spi->dev;
697 struct device_node *phandle;
698 u32 excitation_current = 0, n_wires = 0;
700 rtd = devm_kzalloc(dev, sizeof(*rtd), GFP_KERNEL);
702 return ERR_PTR(-ENOMEM);
704 phandle = of_parse_phandle(child, "adi,rsense-handle", 0);
706 dev_err(dev, "Property adi,rsense-handle missing or invalid");
707 return ERR_PTR(-EINVAL);
710 ret = of_property_read_u32(phandle, "reg", &rtd->r_sense_chan);
712 dev_err(dev, "Property reg must be given\n");
716 ret = of_property_read_u32(child, "adi,number-of-wires", &n_wires);
720 rtd->sensor_config = LTC2983_RTD_N_WIRES(0);
723 rtd->sensor_config = LTC2983_RTD_N_WIRES(1);
726 rtd->sensor_config = LTC2983_RTD_N_WIRES(2);
729 /* 4 wires, Kelvin Rsense */
730 rtd->sensor_config = LTC2983_RTD_N_WIRES(3);
733 dev_err(dev, "Invalid number of wires:%u\n", n_wires);
739 if (of_property_read_bool(child, "adi,rsense-share")) {
740 /* Current rotation is only available with rsense sharing */
741 if (of_property_read_bool(child, "adi,current-rotate")) {
742 if (n_wires == 2 || n_wires == 3) {
744 "Rotation not allowed for 2/3 Wire RTDs");
748 rtd->sensor_config |= LTC2983_RTD_C_ROTATE(1);
750 rtd->sensor_config |= LTC2983_RTD_R_SHARE(1);
754 * rtd channel indexes are a bit more complicated to validate.
755 * For 4wire RTD with rotation, the channel selection cannot be
756 * >=19 since the chann + 1 is used in this configuration.
757 * For 4wire RTDs with kelvin rsense, the rsense channel cannot be
758 * <=1 since chanel - 1 and channel - 2 are used.
760 if (rtd->sensor_config & LTC2983_RTD_4_WIRE_MASK) {
762 u8 min = LTC2983_DIFFERENTIAL_CHAN_MIN,
763 max = LTC2983_MAX_CHANNELS_NR;
765 if (rtd->sensor_config & LTC2983_RTD_ROTATION_MASK)
766 max = LTC2983_MAX_CHANNELS_NR - 1;
768 if (((rtd->sensor_config & LTC2983_RTD_KELVIN_R_SENSE_MASK)
769 == LTC2983_RTD_KELVIN_R_SENSE_MASK) &&
770 (rtd->r_sense_chan <= min)) {
773 "Invalid rsense chann:%d to use in kelvin rsense",
780 if (sensor->chan < min || sensor->chan > max) {
781 dev_err(dev, "Invalid chann:%d for the rtd config",
788 /* same as differential case */
789 if (sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
790 dev_err(&st->spi->dev,
791 "Invalid chann:%d for RTD", sensor->chan);
798 /* check custom sensor */
799 if (sensor->type == LTC2983_SENSOR_RTD_CUSTOM) {
800 rtd->custom = __ltc2983_custom_sensor_new(st, child,
803 if (IS_ERR(rtd->custom)) {
804 of_node_put(phandle);
805 return ERR_CAST(rtd->custom);
809 /* set common parameters */
810 rtd->sensor.fault_handler = ltc2983_common_fault_handler;
811 rtd->sensor.assign_chan = ltc2983_rtd_assign_chan;
813 ret = of_property_read_u32(child, "adi,excitation-current-microamp",
814 &excitation_current);
817 rtd->excitation_current = 1;
819 switch (excitation_current) {
821 rtd->excitation_current = 0x01;
824 rtd->excitation_current = 0x02;
827 rtd->excitation_current = 0x03;
830 rtd->excitation_current = 0x04;
833 rtd->excitation_current = 0x05;
836 rtd->excitation_current = 0x06;
839 rtd->excitation_current = 0x07;
842 rtd->excitation_current = 0x08;
845 dev_err(&st->spi->dev,
846 "Invalid value for excitation current(%u)",
853 of_property_read_u32(child, "adi,rtd-curve", &rtd->rtd_curve);
855 of_node_put(phandle);
858 of_node_put(phandle);
862 static struct ltc2983_sensor *ltc2983_thermistor_new(
863 const struct device_node *child,
864 struct ltc2983_data *st,
865 const struct ltc2983_sensor *sensor)
867 struct ltc2983_thermistor *thermistor;
868 struct device *dev = &st->spi->dev;
869 struct device_node *phandle;
870 u32 excitation_current = 0;
873 thermistor = devm_kzalloc(dev, sizeof(*thermistor), GFP_KERNEL);
875 return ERR_PTR(-ENOMEM);
877 phandle = of_parse_phandle(child, "adi,rsense-handle", 0);
879 dev_err(dev, "Property adi,rsense-handle missing or invalid");
880 return ERR_PTR(-EINVAL);
883 ret = of_property_read_u32(phandle, "reg", &thermistor->r_sense_chan);
885 dev_err(dev, "rsense channel must be configured...\n");
889 if (of_property_read_bool(child, "adi,single-ended")) {
890 thermistor->sensor_config = LTC2983_THERMISTOR_SGL(1);
891 } else if (of_property_read_bool(child, "adi,rsense-share")) {
892 /* rotation is only possible if sharing rsense */
893 if (of_property_read_bool(child, "adi,current-rotate"))
894 thermistor->sensor_config =
895 LTC2983_THERMISTOR_C_ROTATE(1);
897 thermistor->sensor_config =
898 LTC2983_THERMISTOR_R_SHARE(1);
900 /* validate channel index */
901 if (!(thermistor->sensor_config & LTC2983_THERMISTOR_DIFF_MASK) &&
902 sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
903 dev_err(&st->spi->dev,
904 "Invalid chann:%d for differential thermistor",
910 /* check custom sensor */
911 if (sensor->type >= LTC2983_SENSOR_THERMISTOR_STEINHART) {
912 bool steinhart = false;
913 const char *propname;
915 if (sensor->type == LTC2983_SENSOR_THERMISTOR_STEINHART) {
917 propname = "adi,custom-steinhart";
919 propname = "adi,custom-thermistor";
922 thermistor->custom = __ltc2983_custom_sensor_new(st, child,
926 if (IS_ERR(thermistor->custom)) {
927 of_node_put(phandle);
928 return ERR_CAST(thermistor->custom);
931 /* set common parameters */
932 thermistor->sensor.fault_handler = ltc2983_common_fault_handler;
933 thermistor->sensor.assign_chan = ltc2983_thermistor_assign_chan;
935 ret = of_property_read_u32(child, "adi,excitation-current-nanoamp",
936 &excitation_current);
938 /* Auto range is not allowed for custom sensors */
939 if (sensor->type >= LTC2983_SENSOR_THERMISTOR_STEINHART)
941 thermistor->excitation_current = 0x03;
943 /* default to auto-range */
944 thermistor->excitation_current = 0x0c;
946 switch (excitation_current) {
950 LTC2983_SENSOR_THERMISTOR_STEINHART) {
951 dev_err(&st->spi->dev,
952 "Auto Range not allowed for custom sensors\n");
956 thermistor->excitation_current = 0x0c;
959 thermistor->excitation_current = 0x01;
962 thermistor->excitation_current = 0x02;
965 thermistor->excitation_current = 0x03;
968 thermistor->excitation_current = 0x04;
971 thermistor->excitation_current = 0x05;
974 thermistor->excitation_current = 0x06;
977 thermistor->excitation_current = 0x07;
980 thermistor->excitation_current = 0x08;
983 thermistor->excitation_current = 0x09;
986 thermistor->excitation_current = 0x0a;
989 thermistor->excitation_current = 0x0b;
992 dev_err(&st->spi->dev,
993 "Invalid value for excitation current(%u)",
1000 of_node_put(phandle);
1001 return &thermistor->sensor;
1003 of_node_put(phandle);
1004 return ERR_PTR(ret);
1007 static struct ltc2983_sensor *ltc2983_diode_new(
1008 const struct device_node *child,
1009 const struct ltc2983_data *st,
1010 const struct ltc2983_sensor *sensor)
1012 struct ltc2983_diode *diode;
1013 u32 temp = 0, excitation_current = 0;
1016 diode = devm_kzalloc(&st->spi->dev, sizeof(*diode), GFP_KERNEL);
1018 return ERR_PTR(-ENOMEM);
1020 if (of_property_read_bool(child, "adi,single-ended"))
1021 diode->sensor_config = LTC2983_DIODE_SGL(1);
1023 if (of_property_read_bool(child, "adi,three-conversion-cycles"))
1024 diode->sensor_config |= LTC2983_DIODE_3_CONV_CYCLE(1);
1026 if (of_property_read_bool(child, "adi,average-on"))
1027 diode->sensor_config |= LTC2983_DIODE_AVERAGE_ON(1);
1029 /* validate channel index */
1030 if (!(diode->sensor_config & LTC2983_DIODE_DIFF_MASK) &&
1031 sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
1032 dev_err(&st->spi->dev,
1033 "Invalid chann:%d for differential thermistor",
1035 return ERR_PTR(-EINVAL);
1037 /* set common parameters */
1038 diode->sensor.fault_handler = ltc2983_common_fault_handler;
1039 diode->sensor.assign_chan = ltc2983_diode_assign_chan;
1041 ret = of_property_read_u32(child, "adi,excitation-current-microamp",
1042 &excitation_current);
1044 switch (excitation_current) {
1046 diode->excitation_current = 0x00;
1049 diode->excitation_current = 0x01;
1052 diode->excitation_current = 0x02;
1055 diode->excitation_current = 0x03;
1058 dev_err(&st->spi->dev,
1059 "Invalid value for excitation current(%u)",
1060 excitation_current);
1061 return ERR_PTR(-EINVAL);
1065 of_property_read_u32(child, "adi,ideal-factor-value", &temp);
1067 /* 2^20 resolution */
1068 diode->ideal_factor_value = __convert_to_raw(temp, 1048576);
1070 return &diode->sensor;
1073 static struct ltc2983_sensor *ltc2983_r_sense_new(struct device_node *child,
1074 struct ltc2983_data *st,
1075 const struct ltc2983_sensor *sensor)
1077 struct ltc2983_rsense *rsense;
1081 rsense = devm_kzalloc(&st->spi->dev, sizeof(*rsense), GFP_KERNEL);
1083 return ERR_PTR(-ENOMEM);
1085 /* validate channel index */
1086 if (sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
1087 dev_err(&st->spi->dev, "Invalid chann:%d for r_sense",
1089 return ERR_PTR(-EINVAL);
1092 ret = of_property_read_u32(child, "adi,rsense-val-milli-ohms", &temp);
1094 dev_err(&st->spi->dev, "Property adi,rsense-val-milli-ohms missing\n");
1095 return ERR_PTR(-EINVAL);
1098 * Times 1000 because we have milli-ohms and __convert_to_raw
1099 * expects scales of 1000000 which are used for all other
1103 rsense->r_sense_val = __convert_to_raw((u64)temp * 1000, 1024);
1105 /* set common parameters */
1106 rsense->sensor.assign_chan = ltc2983_r_sense_assign_chan;
1108 return &rsense->sensor;
1111 static struct ltc2983_sensor *ltc2983_adc_new(struct device_node *child,
1112 struct ltc2983_data *st,
1113 const struct ltc2983_sensor *sensor)
1115 struct ltc2983_adc *adc;
1117 adc = devm_kzalloc(&st->spi->dev, sizeof(*adc), GFP_KERNEL);
1119 return ERR_PTR(-ENOMEM);
1121 if (of_property_read_bool(child, "adi,single-ended"))
1122 adc->single_ended = true;
1124 if (!adc->single_ended &&
1125 sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
1126 dev_err(&st->spi->dev, "Invalid chan:%d for differential adc\n",
1128 return ERR_PTR(-EINVAL);
1130 /* set common parameters */
1131 adc->sensor.assign_chan = ltc2983_adc_assign_chan;
1132 adc->sensor.fault_handler = ltc2983_common_fault_handler;
1134 return &adc->sensor;
1137 static int ltc2983_chan_read(struct ltc2983_data *st,
1138 const struct ltc2983_sensor *sensor, int *val)
1140 u32 start_conversion = 0;
1144 start_conversion = LTC2983_STATUS_START(true);
1145 start_conversion |= LTC2983_STATUS_CHAN_SEL(sensor->chan);
1146 dev_dbg(&st->spi->dev, "Start conversion on chan:%d, status:%02X\n",
1147 sensor->chan, start_conversion);
1148 /* start conversion */
1149 ret = regmap_write(st->regmap, LTC2983_STATUS_REG, start_conversion);
1153 reinit_completion(&st->completion);
1155 * wait for conversion to complete.
1156 * 300 ms should be more than enough to complete the conversion.
1157 * Depending on the sensor configuration, there are 2/3 conversions
1160 time = wait_for_completion_timeout(&st->completion,
1161 msecs_to_jiffies(300));
1163 dev_warn(&st->spi->dev, "Conversion timed out\n");
1167 /* read the converted data */
1168 ret = regmap_bulk_read(st->regmap, LTC2983_CHAN_RES_ADDR(sensor->chan),
1169 &st->temp, sizeof(st->temp));
1173 *val = __be32_to_cpu(st->temp);
1175 if (!(LTC2983_RES_VALID_MASK & *val)) {
1176 dev_err(&st->spi->dev, "Invalid conversion detected\n");
1180 ret = sensor->fault_handler(st, *val);
1184 *val = sign_extend32((*val) & LTC2983_DATA_MASK, LTC2983_DATA_SIGN_BIT);
1188 static int ltc2983_read_raw(struct iio_dev *indio_dev,
1189 struct iio_chan_spec const *chan,
1190 int *val, int *val2, long mask)
1192 struct ltc2983_data *st = iio_priv(indio_dev);
1196 if (chan->address >= st->num_channels) {
1197 dev_err(&st->spi->dev, "Invalid chan address:%ld",
1203 case IIO_CHAN_INFO_RAW:
1204 mutex_lock(&st->lock);
1205 ret = ltc2983_chan_read(st, st->sensors[chan->address], val);
1206 mutex_unlock(&st->lock);
1207 return ret ?: IIO_VAL_INT;
1208 case IIO_CHAN_INFO_SCALE:
1209 switch (chan->type) {
1211 /* value in milli degrees */
1215 return IIO_VAL_FRACTIONAL;
1217 /* value in millivolt */
1221 return IIO_VAL_FRACTIONAL;
1230 static int ltc2983_reg_access(struct iio_dev *indio_dev,
1232 unsigned int writeval,
1233 unsigned int *readval)
1235 struct ltc2983_data *st = iio_priv(indio_dev);
1238 return regmap_read(st->regmap, reg, readval);
1240 return regmap_write(st->regmap, reg, writeval);
1243 static irqreturn_t ltc2983_irq_handler(int irq, void *data)
1245 struct ltc2983_data *st = data;
1247 complete(&st->completion);
1251 #define LTC2983_CHAN(__type, index, __address) ({ \
1252 struct iio_chan_spec __chan = { \
1256 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
1257 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
1258 .address = __address, \
1263 static int ltc2983_parse_dt(struct ltc2983_data *st)
1265 struct device_node *child;
1266 struct device *dev = &st->spi->dev;
1267 int ret = 0, chan = 0, channel_avail_mask = 0;
1269 of_property_read_u32(dev->of_node, "adi,mux-delay-config-us",
1270 &st->mux_delay_config);
1272 of_property_read_u32(dev->of_node, "adi,filter-notch-freq",
1273 &st->filter_notch_freq);
1275 st->num_channels = of_get_available_child_count(dev->of_node);
1276 st->sensors = devm_kcalloc(dev, st->num_channels, sizeof(*st->sensors),
1281 st->iio_channels = st->num_channels;
1282 for_each_available_child_of_node(dev->of_node, child) {
1283 struct ltc2983_sensor sensor;
1285 ret = of_property_read_u32(child, "reg", &sensor.chan);
1287 dev_err(dev, "reg property must given for child nodes\n");
1291 /* check if we have a valid channel */
1292 if (sensor.chan < LTC2983_MIN_CHANNELS_NR ||
1293 sensor.chan > LTC2983_MAX_CHANNELS_NR) {
1295 "chan:%d must be from 1 to 20\n", sensor.chan);
1297 } else if (channel_avail_mask & BIT(sensor.chan)) {
1298 dev_err(dev, "chan:%d already in use\n", sensor.chan);
1302 ret = of_property_read_u32(child, "adi,sensor-type",
1306 "adi,sensor-type property must given for child nodes\n");
1310 dev_dbg(dev, "Create new sensor, type %u, chann %u",
1314 if (sensor.type >= LTC2983_SENSOR_THERMOCOUPLE &&
1315 sensor.type <= LTC2983_SENSOR_THERMOCOUPLE_CUSTOM) {
1316 st->sensors[chan] = ltc2983_thermocouple_new(child, st,
1318 } else if (sensor.type >= LTC2983_SENSOR_RTD &&
1319 sensor.type <= LTC2983_SENSOR_RTD_CUSTOM) {
1320 st->sensors[chan] = ltc2983_rtd_new(child, st, &sensor);
1321 } else if (sensor.type >= LTC2983_SENSOR_THERMISTOR &&
1322 sensor.type <= LTC2983_SENSOR_THERMISTOR_CUSTOM) {
1323 st->sensors[chan] = ltc2983_thermistor_new(child, st,
1325 } else if (sensor.type == LTC2983_SENSOR_DIODE) {
1326 st->sensors[chan] = ltc2983_diode_new(child, st,
1328 } else if (sensor.type == LTC2983_SENSOR_SENSE_RESISTOR) {
1329 st->sensors[chan] = ltc2983_r_sense_new(child, st,
1331 /* don't add rsense to iio */
1333 } else if (sensor.type == LTC2983_SENSOR_DIRECT_ADC) {
1334 st->sensors[chan] = ltc2983_adc_new(child, st, &sensor);
1336 dev_err(dev, "Unknown sensor type %d\n", sensor.type);
1340 if (IS_ERR(st->sensors[chan])) {
1341 dev_err(dev, "Failed to create sensor %ld",
1342 PTR_ERR(st->sensors[chan]));
1343 return PTR_ERR(st->sensors[chan]);
1345 /* set generic sensor parameters */
1346 st->sensors[chan]->chan = sensor.chan;
1347 st->sensors[chan]->type = sensor.type;
1349 channel_avail_mask |= BIT(sensor.chan);
1356 static int ltc2983_setup(struct ltc2983_data *st, bool assign_iio)
1358 u32 iio_chan_t = 0, iio_chan_v = 0, chan, iio_idx = 0;
1362 /* make sure the device is up */
1363 time = wait_for_completion_timeout(&st->completion,
1364 msecs_to_jiffies(250));
1367 dev_err(&st->spi->dev, "Device startup timed out\n");
1371 st->iio_chan = devm_kzalloc(&st->spi->dev,
1372 st->iio_channels * sizeof(*st->iio_chan),
1378 ret = regmap_update_bits(st->regmap, LTC2983_GLOBAL_CONFIG_REG,
1379 LTC2983_NOTCH_FREQ_MASK,
1380 LTC2983_NOTCH_FREQ(st->filter_notch_freq));
1384 ret = regmap_write(st->regmap, LTC2983_MUX_CONFIG_REG,
1385 st->mux_delay_config);
1389 for (chan = 0; chan < st->num_channels; chan++) {
1390 u32 chan_type = 0, *iio_chan;
1392 ret = st->sensors[chan]->assign_chan(st, st->sensors[chan]);
1396 * The assign_iio flag is necessary for when the device is
1397 * coming out of sleep. In that case, we just need to
1398 * re-configure the device channels.
1399 * We also don't assign iio channels for rsense.
1401 if (st->sensors[chan]->type == LTC2983_SENSOR_SENSE_RESISTOR ||
1405 /* assign iio channel */
1406 if (st->sensors[chan]->type != LTC2983_SENSOR_DIRECT_ADC) {
1407 chan_type = IIO_TEMP;
1408 iio_chan = &iio_chan_t;
1410 chan_type = IIO_VOLTAGE;
1411 iio_chan = &iio_chan_v;
1415 * add chan as the iio .address so that, we can directly
1416 * reference the sensor given the iio_chan_spec
1418 st->iio_chan[iio_idx++] = LTC2983_CHAN(chan_type, (*iio_chan)++,
1425 static const struct regmap_range ltc2983_reg_ranges[] = {
1426 regmap_reg_range(LTC2983_STATUS_REG, LTC2983_STATUS_REG),
1427 regmap_reg_range(LTC2983_TEMP_RES_START_REG, LTC2983_TEMP_RES_END_REG),
1428 regmap_reg_range(LTC2983_GLOBAL_CONFIG_REG, LTC2983_GLOBAL_CONFIG_REG),
1429 regmap_reg_range(LTC2983_MULT_CHANNEL_START_REG,
1430 LTC2983_MULT_CHANNEL_END_REG),
1431 regmap_reg_range(LTC2983_MUX_CONFIG_REG, LTC2983_MUX_CONFIG_REG),
1432 regmap_reg_range(LTC2983_CHAN_ASSIGN_START_REG,
1433 LTC2983_CHAN_ASSIGN_END_REG),
1434 regmap_reg_range(LTC2983_CUST_SENS_TBL_START_REG,
1435 LTC2983_CUST_SENS_TBL_END_REG),
1438 static const struct regmap_access_table ltc2983_reg_table = {
1439 .yes_ranges = ltc2983_reg_ranges,
1440 .n_yes_ranges = ARRAY_SIZE(ltc2983_reg_ranges),
1444 * The reg_bits are actually 12 but the device needs the first *complete*
1445 * byte for the command (R/W).
1447 static const struct regmap_config ltc2983_regmap_config = {
1450 .wr_table = <c2983_reg_table,
1451 .rd_table = <c2983_reg_table,
1452 .read_flag_mask = GENMASK(1, 0),
1453 .write_flag_mask = BIT(1),
1456 static const struct iio_info ltc2983_iio_info = {
1457 .read_raw = ltc2983_read_raw,
1458 .debugfs_reg_access = ltc2983_reg_access,
1461 static int ltc2983_probe(struct spi_device *spi)
1463 struct ltc2983_data *st;
1464 struct iio_dev *indio_dev;
1465 const char *name = spi_get_device_id(spi)->name;
1468 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
1472 st = iio_priv(indio_dev);
1474 st->regmap = devm_regmap_init_spi(spi, <c2983_regmap_config);
1475 if (IS_ERR(st->regmap)) {
1476 dev_err(&spi->dev, "Failed to initialize regmap\n");
1477 return PTR_ERR(st->regmap);
1480 mutex_init(&st->lock);
1481 init_completion(&st->completion);
1483 spi_set_drvdata(spi, st);
1485 ret = ltc2983_parse_dt(st);
1489 * let's request the irq now so it is used to sync the device
1490 * startup in ltc2983_setup()
1492 ret = devm_request_irq(&spi->dev, spi->irq, ltc2983_irq_handler,
1493 IRQF_TRIGGER_RISING, name, st);
1495 dev_err(&spi->dev, "failed to request an irq, %d", ret);
1499 ret = ltc2983_setup(st, true);
1503 indio_dev->dev.parent = &spi->dev;
1504 indio_dev->name = name;
1505 indio_dev->num_channels = st->iio_channels;
1506 indio_dev->channels = st->iio_chan;
1507 indio_dev->modes = INDIO_DIRECT_MODE;
1508 indio_dev->info = <c2983_iio_info;
1510 return devm_iio_device_register(&spi->dev, indio_dev);
1513 static int __maybe_unused ltc2983_resume(struct device *dev)
1515 struct ltc2983_data *st = spi_get_drvdata(to_spi_device(dev));
1518 /* dummy read to bring the device out of sleep */
1519 regmap_read(st->regmap, LTC2983_STATUS_REG, &dummy);
1520 /* we need to re-assign the channels */
1521 return ltc2983_setup(st, false);
1524 static int __maybe_unused ltc2983_suspend(struct device *dev)
1526 struct ltc2983_data *st = spi_get_drvdata(to_spi_device(dev));
1528 return regmap_write(st->regmap, LTC2983_STATUS_REG, LTC2983_SLEEP);
1531 static SIMPLE_DEV_PM_OPS(ltc2983_pm_ops, ltc2983_suspend, ltc2983_resume);
1533 static const struct spi_device_id ltc2983_id_table[] = {
1537 MODULE_DEVICE_TABLE(spi, ltc2983_id_table);
1539 static const struct of_device_id ltc2983_of_match[] = {
1540 { .compatible = "adi,ltc2983" },
1543 MODULE_DEVICE_TABLE(of, ltc2983_of_match);
1545 static struct spi_driver ltc2983_driver = {
1548 .of_match_table = ltc2983_of_match,
1549 .pm = <c2983_pm_ops,
1551 .probe = ltc2983_probe,
1552 .id_table = ltc2983_id_table,
1555 module_spi_driver(ltc2983_driver);
1557 MODULE_AUTHOR("Nuno Sa <nuno.sa@analog.com>");
1558 MODULE_DESCRIPTION("Analog Devices LTC2983 SPI Temperature sensors");
1559 MODULE_LICENSE("GPL");