// SPDX-License-Identifier: GPL-2.0 /* * Analog Devices LTC2983 Multi-Sensor Digital Temperature Measurement System * driver * * Copyright 2019 Analog Devices Inc. */ #include #include #include #include #include #include #include #include #include #include #include /* register map */ #define LTC2983_STATUS_REG 0x0000 #define LTC2983_TEMP_RES_START_REG 0x0010 #define LTC2983_TEMP_RES_END_REG 0x005F #define LTC2983_GLOBAL_CONFIG_REG 0x00F0 #define LTC2983_MULT_CHANNEL_START_REG 0x00F4 #define LTC2983_MULT_CHANNEL_END_REG 0x00F7 #define LTC2983_MUX_CONFIG_REG 0x00FF #define LTC2983_CHAN_ASSIGN_START_REG 0x0200 #define LTC2983_CHAN_ASSIGN_END_REG 0x024F #define LTC2983_CUST_SENS_TBL_START_REG 0x0250 #define LTC2983_CUST_SENS_TBL_END_REG 0x03CF #define LTC2983_DIFFERENTIAL_CHAN_MIN 2 #define LTC2983_MAX_CHANNELS_NR 20 #define LTC2983_MIN_CHANNELS_NR 1 #define LTC2983_SLEEP 0x97 #define LTC2983_CUSTOM_STEINHART_SIZE 24 #define LTC2983_CUSTOM_SENSOR_ENTRY_SZ 6 #define LTC2983_CUSTOM_STEINHART_ENTRY_SZ 4 #define LTC2983_CHAN_START_ADDR(chan) \ (((chan - 1) * 4) + LTC2983_CHAN_ASSIGN_START_REG) #define LTC2983_CHAN_RES_ADDR(chan) \ (((chan - 1) * 4) + LTC2983_TEMP_RES_START_REG) #define LTC2983_THERMOCOUPLE_DIFF_MASK BIT(3) #define LTC2983_THERMOCOUPLE_SGL(x) \ FIELD_PREP(LTC2983_THERMOCOUPLE_DIFF_MASK, x) #define LTC2983_THERMOCOUPLE_OC_CURR_MASK GENMASK(1, 0) #define LTC2983_THERMOCOUPLE_OC_CURR(x) \ FIELD_PREP(LTC2983_THERMOCOUPLE_OC_CURR_MASK, x) #define LTC2983_THERMOCOUPLE_OC_CHECK_MASK BIT(2) #define LTC2983_THERMOCOUPLE_OC_CHECK(x) \ FIELD_PREP(LTC2983_THERMOCOUPLE_OC_CHECK_MASK, x) #define LTC2983_THERMISTOR_DIFF_MASK BIT(2) #define LTC2983_THERMISTOR_SGL(x) \ FIELD_PREP(LTC2983_THERMISTOR_DIFF_MASK, x) #define LTC2983_THERMISTOR_R_SHARE_MASK BIT(1) #define LTC2983_THERMISTOR_R_SHARE(x) \ FIELD_PREP(LTC2983_THERMISTOR_R_SHARE_MASK, x) #define LTC2983_THERMISTOR_C_ROTATE_MASK BIT(0) #define LTC2983_THERMISTOR_C_ROTATE(x) \ FIELD_PREP(LTC2983_THERMISTOR_C_ROTATE_MASK, x) #define LTC2983_DIODE_DIFF_MASK BIT(2) #define LTC2983_DIODE_SGL(x) \ FIELD_PREP(LTC2983_DIODE_DIFF_MASK, x) #define LTC2983_DIODE_3_CONV_CYCLE_MASK BIT(1) #define LTC2983_DIODE_3_CONV_CYCLE(x) \ FIELD_PREP(LTC2983_DIODE_3_CONV_CYCLE_MASK, x) #define LTC2983_DIODE_AVERAGE_ON_MASK BIT(0) #define LTC2983_DIODE_AVERAGE_ON(x) \ FIELD_PREP(LTC2983_DIODE_AVERAGE_ON_MASK, x) #define LTC2983_RTD_4_WIRE_MASK BIT(3) #define LTC2983_RTD_ROTATION_MASK BIT(1) #define LTC2983_RTD_C_ROTATE(x) \ FIELD_PREP(LTC2983_RTD_ROTATION_MASK, x) #define LTC2983_RTD_KELVIN_R_SENSE_MASK GENMASK(3, 2) #define LTC2983_RTD_N_WIRES_MASK GENMASK(3, 2) #define LTC2983_RTD_N_WIRES(x) \ FIELD_PREP(LTC2983_RTD_N_WIRES_MASK, x) #define LTC2983_RTD_R_SHARE_MASK BIT(0) #define LTC2983_RTD_R_SHARE(x) \ FIELD_PREP(LTC2983_RTD_R_SHARE_MASK, 1) #define LTC2983_COMMON_HARD_FAULT_MASK GENMASK(31, 30) #define LTC2983_COMMON_SOFT_FAULT_MASK GENMASK(27, 25) #define LTC2983_STATUS_START_MASK BIT(7) #define LTC2983_STATUS_START(x) FIELD_PREP(LTC2983_STATUS_START_MASK, x) #define LTC2983_STATUS_CHAN_SEL_MASK GENMASK(4, 0) #define LTC2983_STATUS_CHAN_SEL(x) \ FIELD_PREP(LTC2983_STATUS_CHAN_SEL_MASK, x) #define LTC2983_TEMP_UNITS_MASK BIT(2) #define LTC2983_TEMP_UNITS(x) FIELD_PREP(LTC2983_TEMP_UNITS_MASK, x) #define LTC2983_NOTCH_FREQ_MASK GENMASK(1, 0) #define LTC2983_NOTCH_FREQ(x) FIELD_PREP(LTC2983_NOTCH_FREQ_MASK, x) #define LTC2983_RES_VALID_MASK BIT(24) #define LTC2983_DATA_MASK GENMASK(23, 0) #define LTC2983_DATA_SIGN_BIT 23 #define LTC2983_CHAN_TYPE_MASK GENMASK(31, 27) #define LTC2983_CHAN_TYPE(x) FIELD_PREP(LTC2983_CHAN_TYPE_MASK, x) /* cold junction for thermocouples and rsense for rtd's and thermistor's */ #define LTC2983_CHAN_ASSIGN_MASK GENMASK(26, 22) #define LTC2983_CHAN_ASSIGN(x) FIELD_PREP(LTC2983_CHAN_ASSIGN_MASK, x) #define LTC2983_CUSTOM_LEN_MASK GENMASK(5, 0) #define LTC2983_CUSTOM_LEN(x) FIELD_PREP(LTC2983_CUSTOM_LEN_MASK, x) #define LTC2983_CUSTOM_ADDR_MASK GENMASK(11, 6) #define LTC2983_CUSTOM_ADDR(x) FIELD_PREP(LTC2983_CUSTOM_ADDR_MASK, x) #define LTC2983_THERMOCOUPLE_CFG_MASK GENMASK(21, 18) #define LTC2983_THERMOCOUPLE_CFG(x) \ FIELD_PREP(LTC2983_THERMOCOUPLE_CFG_MASK, x) #define LTC2983_THERMOCOUPLE_HARD_FAULT_MASK GENMASK(31, 29) #define LTC2983_THERMOCOUPLE_SOFT_FAULT_MASK GENMASK(28, 25) #define LTC2983_RTD_CFG_MASK GENMASK(21, 18) #define LTC2983_RTD_CFG(x) FIELD_PREP(LTC2983_RTD_CFG_MASK, x) #define LTC2983_RTD_EXC_CURRENT_MASK GENMASK(17, 14) #define LTC2983_RTD_EXC_CURRENT(x) \ FIELD_PREP(LTC2983_RTD_EXC_CURRENT_MASK, x) #define LTC2983_RTD_CURVE_MASK GENMASK(13, 12) #define LTC2983_RTD_CURVE(x) FIELD_PREP(LTC2983_RTD_CURVE_MASK, x) #define LTC2983_THERMISTOR_CFG_MASK GENMASK(21, 19) #define LTC2983_THERMISTOR_CFG(x) \ FIELD_PREP(LTC2983_THERMISTOR_CFG_MASK, x) #define LTC2983_THERMISTOR_EXC_CURRENT_MASK GENMASK(18, 15) #define LTC2983_THERMISTOR_EXC_CURRENT(x) \ FIELD_PREP(LTC2983_THERMISTOR_EXC_CURRENT_MASK, x) #define LTC2983_DIODE_CFG_MASK GENMASK(26, 24) #define LTC2983_DIODE_CFG(x) FIELD_PREP(LTC2983_DIODE_CFG_MASK, x) #define LTC2983_DIODE_EXC_CURRENT_MASK GENMASK(23, 22) #define LTC2983_DIODE_EXC_CURRENT(x) \ FIELD_PREP(LTC2983_DIODE_EXC_CURRENT_MASK, x) #define LTC2983_DIODE_IDEAL_FACTOR_MASK GENMASK(21, 0) #define LTC2983_DIODE_IDEAL_FACTOR(x) \ FIELD_PREP(LTC2983_DIODE_IDEAL_FACTOR_MASK, x) #define LTC2983_R_SENSE_VAL_MASK GENMASK(26, 0) #define LTC2983_R_SENSE_VAL(x) FIELD_PREP(LTC2983_R_SENSE_VAL_MASK, x) #define LTC2983_ADC_SINGLE_ENDED_MASK BIT(26) #define LTC2983_ADC_SINGLE_ENDED(x) \ FIELD_PREP(LTC2983_ADC_SINGLE_ENDED_MASK, x) enum { LTC2983_SENSOR_THERMOCOUPLE = 1, LTC2983_SENSOR_THERMOCOUPLE_CUSTOM = 9, LTC2983_SENSOR_RTD = 10, LTC2983_SENSOR_RTD_CUSTOM = 18, LTC2983_SENSOR_THERMISTOR = 19, LTC2983_SENSOR_THERMISTOR_STEINHART = 26, LTC2983_SENSOR_THERMISTOR_CUSTOM = 27, LTC2983_SENSOR_DIODE = 28, LTC2983_SENSOR_SENSE_RESISTOR = 29, LTC2983_SENSOR_DIRECT_ADC = 30, }; #define to_thermocouple(_sensor) \ container_of(_sensor, struct ltc2983_thermocouple, sensor) #define to_rtd(_sensor) \ container_of(_sensor, struct ltc2983_rtd, sensor) #define to_thermistor(_sensor) \ container_of(_sensor, struct ltc2983_thermistor, sensor) #define to_diode(_sensor) \ container_of(_sensor, struct ltc2983_diode, sensor) #define to_rsense(_sensor) \ container_of(_sensor, struct ltc2983_rsense, sensor) #define to_adc(_sensor) \ container_of(_sensor, struct ltc2983_adc, sensor) struct ltc2983_data { struct regmap *regmap; struct spi_device *spi; struct mutex lock; struct completion completion; struct iio_chan_spec *iio_chan; struct ltc2983_sensor **sensors; u32 mux_delay_config; u32 filter_notch_freq; u16 custom_table_size; u8 num_channels; u8 iio_channels; /* * DMA (thus cache coherency maintenance) requires the * transfer buffers to live in their own cache lines. * Holds the converted temperature */ __be32 temp ____cacheline_aligned; }; struct ltc2983_sensor { int (*fault_handler)(const struct ltc2983_data *st, const u32 result); int (*assign_chan)(struct ltc2983_data *st, const struct ltc2983_sensor *sensor); /* specifies the sensor channel */ u32 chan; /* sensor type */ u32 type; }; struct ltc2983_custom_sensor { /* raw table sensor data */ u8 *table; size_t size; /* address offset */ s8 offset; bool is_steinhart; }; struct ltc2983_thermocouple { struct ltc2983_sensor sensor; struct ltc2983_custom_sensor *custom; u32 sensor_config; u32 cold_junction_chan; }; struct ltc2983_rtd { struct ltc2983_sensor sensor; struct ltc2983_custom_sensor *custom; u32 sensor_config; u32 r_sense_chan; u32 excitation_current; u32 rtd_curve; }; struct ltc2983_thermistor { struct ltc2983_sensor sensor; struct ltc2983_custom_sensor *custom; u32 sensor_config; u32 r_sense_chan; u32 excitation_current; }; struct ltc2983_diode { struct ltc2983_sensor sensor; u32 sensor_config; u32 excitation_current; u32 ideal_factor_value; }; struct ltc2983_rsense { struct ltc2983_sensor sensor; u32 r_sense_val; }; struct ltc2983_adc { struct ltc2983_sensor sensor; bool single_ended; }; /* * Convert to Q format numbers. These number's are integers where * the number of integer and fractional bits are specified. The resolution * is given by 1/@resolution and tell us the number of fractional bits. For * instance a resolution of 2^-10 means we have 10 fractional bits. */ static u32 __convert_to_raw(const u64 val, const u32 resolution) { u64 __res = val * resolution; /* all values are multiplied by 1000000 to remove the fraction */ do_div(__res, 1000000); return __res; } static u32 __convert_to_raw_sign(const u64 val, const u32 resolution) { s64 __res = -(s32)val; __res = __convert_to_raw(__res, resolution); return (u32)-__res; } static int __ltc2983_fault_handler(const struct ltc2983_data *st, const u32 result, const u32 hard_mask, const u32 soft_mask) { const struct device *dev = &st->spi->dev; if (result & hard_mask) { dev_err(dev, "Invalid conversion: Sensor HARD fault\n"); return -EIO; } else if (result & soft_mask) { /* just print a warning */ dev_warn(dev, "Suspicious conversion: Sensor SOFT fault\n"); } return 0; } static int __ltc2983_chan_assign_common(const struct ltc2983_data *st, const struct ltc2983_sensor *sensor, u32 chan_val) { u32 reg = LTC2983_CHAN_START_ADDR(sensor->chan); __be32 __chan_val; chan_val |= LTC2983_CHAN_TYPE(sensor->type); dev_dbg(&st->spi->dev, "Assign reg:0x%04X, val:0x%08X\n", reg, chan_val); __chan_val = cpu_to_be32(chan_val); return regmap_bulk_write(st->regmap, reg, &__chan_val, sizeof(__chan_val)); } static int __ltc2983_chan_custom_sensor_assign(struct ltc2983_data *st, struct ltc2983_custom_sensor *custom, u32 *chan_val) { u32 reg; u8 mult = custom->is_steinhart ? LTC2983_CUSTOM_STEINHART_ENTRY_SZ : LTC2983_CUSTOM_SENSOR_ENTRY_SZ; const struct device *dev = &st->spi->dev; /* * custom->size holds the raw size of the table. However, when * configuring the sensor channel, we must write the number of * entries of the table minus 1. For steinhart sensors 0 is written * since the size is constant! */ const u8 len = custom->is_steinhart ? 0 : (custom->size / LTC2983_CUSTOM_SENSOR_ENTRY_SZ) - 1; /* * Check if the offset was assigned already. It should be for steinhart * sensors. When coming from sleep, it should be assigned for all. */ if (custom->offset < 0) { /* * This needs to be done again here because, from the moment * when this test was done (successfully) for this custom * sensor, a steinhart sensor might have been added changing * custom_table_size... */ if (st->custom_table_size + custom->size > (LTC2983_CUST_SENS_TBL_END_REG - LTC2983_CUST_SENS_TBL_START_REG) + 1) { dev_err(dev, "Not space left(%d) for new custom sensor(%zu)", st->custom_table_size, custom->size); return -EINVAL; } custom->offset = st->custom_table_size / LTC2983_CUSTOM_SENSOR_ENTRY_SZ; st->custom_table_size += custom->size; } reg = (custom->offset * mult) + LTC2983_CUST_SENS_TBL_START_REG; *chan_val |= LTC2983_CUSTOM_LEN(len); *chan_val |= LTC2983_CUSTOM_ADDR(custom->offset); dev_dbg(dev, "Assign custom sensor, reg:0x%04X, off:%d, sz:%zu", reg, custom->offset, custom->size); /* write custom sensor table */ return regmap_bulk_write(st->regmap, reg, custom->table, custom->size); } static struct ltc2983_custom_sensor *__ltc2983_custom_sensor_new( struct ltc2983_data *st, const struct device_node *np, const char *propname, const bool is_steinhart, const u32 resolution, const bool has_signed) { struct ltc2983_custom_sensor *new_custom; u8 index, n_entries, tbl = 0; struct device *dev = &st->spi->dev; /* * For custom steinhart, the full u32 is taken. For all the others * the MSB is discarded. */ const u8 n_size = (is_steinhart == true) ? 4 : 3; const u8 e_size = (is_steinhart == true) ? sizeof(u32) : sizeof(u64); n_entries = of_property_count_elems_of_size(np, propname, e_size); /* n_entries must be an even number */ if (!n_entries || (n_entries % 2) != 0) { dev_err(dev, "Number of entries either 0 or not even\n"); return ERR_PTR(-EINVAL); } new_custom = devm_kzalloc(dev, sizeof(*new_custom), GFP_KERNEL); if (!new_custom) return ERR_PTR(-ENOMEM); new_custom->size = n_entries * n_size; /* check Steinhart size */ if (is_steinhart && new_custom->size != LTC2983_CUSTOM_STEINHART_SIZE) { dev_err(dev, "Steinhart sensors size(%zu) must be 24", new_custom->size); return ERR_PTR(-EINVAL); } /* Check space on the table. */ if (st->custom_table_size + new_custom->size > (LTC2983_CUST_SENS_TBL_END_REG - LTC2983_CUST_SENS_TBL_START_REG) + 1) { dev_err(dev, "No space left(%d) for new custom sensor(%zu)", st->custom_table_size, new_custom->size); return ERR_PTR(-EINVAL); } /* allocate the table */ new_custom->table = devm_kzalloc(dev, new_custom->size, GFP_KERNEL); if (!new_custom->table) return ERR_PTR(-ENOMEM); for (index = 0; index < n_entries; index++) { u64 temp = 0, j; /* * Steinhart sensors are configured with raw values in the * devicetree. For the other sensors we must convert the * value to raw. The odd index's correspond to temperarures * and always have 1/1024 of resolution. Temperatures also * come in kelvin, so signed values is not possible */ if (!is_steinhart) { of_property_read_u64_index(np, propname, index, &temp); if ((index % 2) != 0) temp = __convert_to_raw(temp, 1024); else if (has_signed && (s64)temp < 0) temp = __convert_to_raw_sign(temp, resolution); else temp = __convert_to_raw(temp, resolution); } else { u32 t32; of_property_read_u32_index(np, propname, index, &t32); temp = t32; } for (j = 0; j < n_size; j++) new_custom->table[tbl++] = temp >> (8 * (n_size - j - 1)); } new_custom->is_steinhart = is_steinhart; /* * This is done to first add all the steinhart sensors to the table, * in order to maximize the table usage. If we mix adding steinhart * with the other sensors, we might have to do some roundup to make * sure that sensor_addr - 0x250(start address) is a multiple of 4 * (for steinhart), and a multiple of 6 for all the other sensors. * Since we have const 24 bytes for steinhart sensors and 24 is * also a multiple of 6, we guarantee that the first non-steinhart * sensor will sit in a correct address without the need of filling * addresses. */ if (is_steinhart) { new_custom->offset = st->custom_table_size / LTC2983_CUSTOM_STEINHART_ENTRY_SZ; st->custom_table_size += new_custom->size; } else { /* mark as unset. This is checked later on the assign phase */ new_custom->offset = -1; } return new_custom; } static int ltc2983_thermocouple_fault_handler(const struct ltc2983_data *st, const u32 result) { return __ltc2983_fault_handler(st, result, LTC2983_THERMOCOUPLE_HARD_FAULT_MASK, LTC2983_THERMOCOUPLE_SOFT_FAULT_MASK); } static int ltc2983_common_fault_handler(const struct ltc2983_data *st, const u32 result) { return __ltc2983_fault_handler(st, result, LTC2983_COMMON_HARD_FAULT_MASK, LTC2983_COMMON_SOFT_FAULT_MASK); } static int ltc2983_thermocouple_assign_chan(struct ltc2983_data *st, const struct ltc2983_sensor *sensor) { struct ltc2983_thermocouple *thermo = to_thermocouple(sensor); u32 chan_val; chan_val = LTC2983_CHAN_ASSIGN(thermo->cold_junction_chan); chan_val |= LTC2983_THERMOCOUPLE_CFG(thermo->sensor_config); if (thermo->custom) { int ret; ret = __ltc2983_chan_custom_sensor_assign(st, thermo->custom, &chan_val); if (ret) return ret; } return __ltc2983_chan_assign_common(st, sensor, chan_val); } static int ltc2983_rtd_assign_chan(struct ltc2983_data *st, const struct ltc2983_sensor *sensor) { struct ltc2983_rtd *rtd = to_rtd(sensor); u32 chan_val; chan_val = LTC2983_CHAN_ASSIGN(rtd->r_sense_chan); chan_val |= LTC2983_RTD_CFG(rtd->sensor_config); chan_val |= LTC2983_RTD_EXC_CURRENT(rtd->excitation_current); chan_val |= LTC2983_RTD_CURVE(rtd->rtd_curve); if (rtd->custom) { int ret; ret = __ltc2983_chan_custom_sensor_assign(st, rtd->custom, &chan_val); if (ret) return ret; } return __ltc2983_chan_assign_common(st, sensor, chan_val); } static int ltc2983_thermistor_assign_chan(struct ltc2983_data *st, const struct ltc2983_sensor *sensor) { struct ltc2983_thermistor *thermistor = to_thermistor(sensor); u32 chan_val; chan_val = LTC2983_CHAN_ASSIGN(thermistor->r_sense_chan); chan_val |= LTC2983_THERMISTOR_CFG(thermistor->sensor_config); chan_val |= LTC2983_THERMISTOR_EXC_CURRENT(thermistor->excitation_current); if (thermistor->custom) { int ret; ret = __ltc2983_chan_custom_sensor_assign(st, thermistor->custom, &chan_val); if (ret) return ret; } return __ltc2983_chan_assign_common(st, sensor, chan_val); } static int ltc2983_diode_assign_chan(struct ltc2983_data *st, const struct ltc2983_sensor *sensor) { struct ltc2983_diode *diode = to_diode(sensor); u32 chan_val; chan_val = LTC2983_DIODE_CFG(diode->sensor_config); chan_val |= LTC2983_DIODE_EXC_CURRENT(diode->excitation_current); chan_val |= LTC2983_DIODE_IDEAL_FACTOR(diode->ideal_factor_value); return __ltc2983_chan_assign_common(st, sensor, chan_val); } static int ltc2983_r_sense_assign_chan(struct ltc2983_data *st, const struct ltc2983_sensor *sensor) { struct ltc2983_rsense *rsense = to_rsense(sensor); u32 chan_val; chan_val = LTC2983_R_SENSE_VAL(rsense->r_sense_val); return __ltc2983_chan_assign_common(st, sensor, chan_val); } static int ltc2983_adc_assign_chan(struct ltc2983_data *st, const struct ltc2983_sensor *sensor) { struct ltc2983_adc *adc = to_adc(sensor); u32 chan_val; chan_val = LTC2983_ADC_SINGLE_ENDED(adc->single_ended); return __ltc2983_chan_assign_common(st, sensor, chan_val); } static struct ltc2983_sensor *ltc2983_thermocouple_new( const struct device_node *child, struct ltc2983_data *st, const struct ltc2983_sensor *sensor) { struct ltc2983_thermocouple *thermo; struct device_node *phandle; u32 oc_current; int ret; thermo = devm_kzalloc(&st->spi->dev, sizeof(*thermo), GFP_KERNEL); if (!thermo) return ERR_PTR(-ENOMEM); if (of_property_read_bool(child, "adi,single-ended")) thermo->sensor_config = LTC2983_THERMOCOUPLE_SGL(1); ret = of_property_read_u32(child, "adi,sensor-oc-current-microamp", &oc_current); if (!ret) { switch (oc_current) { case 10: thermo->sensor_config |= LTC2983_THERMOCOUPLE_OC_CURR(0); break; case 100: thermo->sensor_config |= LTC2983_THERMOCOUPLE_OC_CURR(1); break; case 500: thermo->sensor_config |= LTC2983_THERMOCOUPLE_OC_CURR(2); break; case 1000: thermo->sensor_config |= LTC2983_THERMOCOUPLE_OC_CURR(3); break; default: dev_err(&st->spi->dev, "Invalid open circuit current:%u", oc_current); return ERR_PTR(-EINVAL); } thermo->sensor_config |= LTC2983_THERMOCOUPLE_OC_CHECK(1); } /* validate channel index */ if (!(thermo->sensor_config & LTC2983_THERMOCOUPLE_DIFF_MASK) && sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) { dev_err(&st->spi->dev, "Invalid chann:%d for differential thermocouple", sensor->chan); return ERR_PTR(-EINVAL); } phandle = of_parse_phandle(child, "adi,cold-junction-handle", 0); if (phandle) { int ret; ret = of_property_read_u32(phandle, "reg", &thermo->cold_junction_chan); if (ret) { /* * This would be catched later but we can just return * the error right away. */ dev_err(&st->spi->dev, "Property reg must be given\n"); of_node_put(phandle); return ERR_PTR(-EINVAL); } } /* check custom sensor */ if (sensor->type == LTC2983_SENSOR_THERMOCOUPLE_CUSTOM) { const char *propname = "adi,custom-thermocouple"; thermo->custom = __ltc2983_custom_sensor_new(st, child, propname, false, 16384, true); if (IS_ERR(thermo->custom)) { of_node_put(phandle); return ERR_CAST(thermo->custom); } } /* set common parameters */ thermo->sensor.fault_handler = ltc2983_thermocouple_fault_handler; thermo->sensor.assign_chan = ltc2983_thermocouple_assign_chan; of_node_put(phandle); return &thermo->sensor; } static struct ltc2983_sensor *ltc2983_rtd_new(const struct device_node *child, struct ltc2983_data *st, const struct ltc2983_sensor *sensor) { struct ltc2983_rtd *rtd; int ret = 0; struct device *dev = &st->spi->dev; struct device_node *phandle; u32 excitation_current = 0, n_wires = 0; rtd = devm_kzalloc(dev, sizeof(*rtd), GFP_KERNEL); if (!rtd) return ERR_PTR(-ENOMEM); phandle = of_parse_phandle(child, "adi,rsense-handle", 0); if (!phandle) { dev_err(dev, "Property adi,rsense-handle missing or invalid"); return ERR_PTR(-EINVAL); } ret = of_property_read_u32(phandle, "reg", &rtd->r_sense_chan); if (ret) { dev_err(dev, "Property reg must be given\n"); goto fail; } ret = of_property_read_u32(child, "adi,number-of-wires", &n_wires); if (!ret) { switch (n_wires) { case 2: rtd->sensor_config = LTC2983_RTD_N_WIRES(0); break; case 3: rtd->sensor_config = LTC2983_RTD_N_WIRES(1); break; case 4: rtd->sensor_config = LTC2983_RTD_N_WIRES(2); break; case 5: /* 4 wires, Kelvin Rsense */ rtd->sensor_config = LTC2983_RTD_N_WIRES(3); break; default: dev_err(dev, "Invalid number of wires:%u\n", n_wires); ret = -EINVAL; goto fail; } } if (of_property_read_bool(child, "adi,rsense-share")) { /* Current rotation is only available with rsense sharing */ if (of_property_read_bool(child, "adi,current-rotate")) { if (n_wires == 2 || n_wires == 3) { dev_err(dev, "Rotation not allowed for 2/3 Wire RTDs"); ret = -EINVAL; goto fail; } rtd->sensor_config |= LTC2983_RTD_C_ROTATE(1); } else { rtd->sensor_config |= LTC2983_RTD_R_SHARE(1); } } /* * rtd channel indexes are a bit more complicated to validate. * For 4wire RTD with rotation, the channel selection cannot be * >=19 since the chann + 1 is used in this configuration. * For 4wire RTDs with kelvin rsense, the rsense channel cannot be * <=1 since chanel - 1 and channel - 2 are used. */ if (rtd->sensor_config & LTC2983_RTD_4_WIRE_MASK) { /* 4-wire */ u8 min = LTC2983_DIFFERENTIAL_CHAN_MIN, max = LTC2983_MAX_CHANNELS_NR; if (rtd->sensor_config & LTC2983_RTD_ROTATION_MASK) max = LTC2983_MAX_CHANNELS_NR - 1; if (((rtd->sensor_config & LTC2983_RTD_KELVIN_R_SENSE_MASK) == LTC2983_RTD_KELVIN_R_SENSE_MASK) && (rtd->r_sense_chan <= min)) { /* kelvin rsense*/ dev_err(dev, "Invalid rsense chann:%d to use in kelvin rsense", rtd->r_sense_chan); ret = -EINVAL; goto fail; } if (sensor->chan < min || sensor->chan > max) { dev_err(dev, "Invalid chann:%d for the rtd config", sensor->chan); ret = -EINVAL; goto fail; } } else { /* same as differential case */ if (sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) { dev_err(&st->spi->dev, "Invalid chann:%d for RTD", sensor->chan); ret = -EINVAL; goto fail; } } /* check custom sensor */ if (sensor->type == LTC2983_SENSOR_RTD_CUSTOM) { rtd->custom = __ltc2983_custom_sensor_new(st, child, "adi,custom-rtd", false, 2048, false); if (IS_ERR(rtd->custom)) { of_node_put(phandle); return ERR_CAST(rtd->custom); } } /* set common parameters */ rtd->sensor.fault_handler = ltc2983_common_fault_handler; rtd->sensor.assign_chan = ltc2983_rtd_assign_chan; ret = of_property_read_u32(child, "adi,excitation-current-microamp", &excitation_current); if (ret) { /* default to 5uA */ rtd->excitation_current = 1; } else { switch (excitation_current) { case 5: rtd->excitation_current = 0x01; break; case 10: rtd->excitation_current = 0x02; break; case 25: rtd->excitation_current = 0x03; break; case 50: rtd->excitation_current = 0x04; break; case 100: rtd->excitation_current = 0x05; break; case 250: rtd->excitation_current = 0x06; break; case 500: rtd->excitation_current = 0x07; break; case 1000: rtd->excitation_current = 0x08; break; default: dev_err(&st->spi->dev, "Invalid value for excitation current(%u)", excitation_current); ret = -EINVAL; goto fail; } } of_property_read_u32(child, "adi,rtd-curve", &rtd->rtd_curve); of_node_put(phandle); return &rtd->sensor; fail: of_node_put(phandle); return ERR_PTR(ret); } static struct ltc2983_sensor *ltc2983_thermistor_new( const struct device_node *child, struct ltc2983_data *st, const struct ltc2983_sensor *sensor) { struct ltc2983_thermistor *thermistor; struct device *dev = &st->spi->dev; struct device_node *phandle; u32 excitation_current = 0; int ret = 0; thermistor = devm_kzalloc(dev, sizeof(*thermistor), GFP_KERNEL); if (!thermistor) return ERR_PTR(-ENOMEM); phandle = of_parse_phandle(child, "adi,rsense-handle", 0); if (!phandle) { dev_err(dev, "Property adi,rsense-handle missing or invalid"); return ERR_PTR(-EINVAL); } ret = of_property_read_u32(phandle, "reg", &thermistor->r_sense_chan); if (ret) { dev_err(dev, "rsense channel must be configured...\n"); goto fail; } if (of_property_read_bool(child, "adi,single-ended")) { thermistor->sensor_config = LTC2983_THERMISTOR_SGL(1); } else if (of_property_read_bool(child, "adi,rsense-share")) { /* rotation is only possible if sharing rsense */ if (of_property_read_bool(child, "adi,current-rotate")) thermistor->sensor_config = LTC2983_THERMISTOR_C_ROTATE(1); else thermistor->sensor_config = LTC2983_THERMISTOR_R_SHARE(1); } /* validate channel index */ if (!(thermistor->sensor_config & LTC2983_THERMISTOR_DIFF_MASK) && sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) { dev_err(&st->spi->dev, "Invalid chann:%d for differential thermistor", sensor->chan); ret = -EINVAL; goto fail; } /* check custom sensor */ if (sensor->type >= LTC2983_SENSOR_THERMISTOR_STEINHART) { bool steinhart = false; const char *propname; if (sensor->type == LTC2983_SENSOR_THERMISTOR_STEINHART) { steinhart = true; propname = "adi,custom-steinhart"; } else { propname = "adi,custom-thermistor"; } thermistor->custom = __ltc2983_custom_sensor_new(st, child, propname, steinhart, 64, false); if (IS_ERR(thermistor->custom)) { of_node_put(phandle); return ERR_CAST(thermistor->custom); } } /* set common parameters */ thermistor->sensor.fault_handler = ltc2983_common_fault_handler; thermistor->sensor.assign_chan = ltc2983_thermistor_assign_chan; ret = of_property_read_u32(child, "adi,excitation-current-nanoamp", &excitation_current); if (ret) { /* Auto range is not allowed for custom sensors */ if (sensor->type >= LTC2983_SENSOR_THERMISTOR_STEINHART) /* default to 1uA */ thermistor->excitation_current = 0x03; else /* default to auto-range */ thermistor->excitation_current = 0x0c; } else { switch (excitation_current) { case 0: /* auto range */ if (sensor->type >= LTC2983_SENSOR_THERMISTOR_STEINHART) { dev_err(&st->spi->dev, "Auto Range not allowed for custom sensors\n"); ret = -EINVAL; goto fail; } thermistor->excitation_current = 0x0c; break; case 250: thermistor->excitation_current = 0x01; break; case 500: thermistor->excitation_current = 0x02; break; case 1000: thermistor->excitation_current = 0x03; break; case 5000: thermistor->excitation_current = 0x04; break; case 10000: thermistor->excitation_current = 0x05; break; case 25000: thermistor->excitation_current = 0x06; break; case 50000: thermistor->excitation_current = 0x07; break; case 100000: thermistor->excitation_current = 0x08; break; case 250000: thermistor->excitation_current = 0x09; break; case 500000: thermistor->excitation_current = 0x0a; break; case 1000000: thermistor->excitation_current = 0x0b; break; default: dev_err(&st->spi->dev, "Invalid value for excitation current(%u)", excitation_current); ret = -EINVAL; goto fail; } } of_node_put(phandle); return &thermistor->sensor; fail: of_node_put(phandle); return ERR_PTR(ret); } static struct ltc2983_sensor *ltc2983_diode_new( const struct device_node *child, const struct ltc2983_data *st, const struct ltc2983_sensor *sensor) { struct ltc2983_diode *diode; u32 temp = 0, excitation_current = 0; int ret; diode = devm_kzalloc(&st->spi->dev, sizeof(*diode), GFP_KERNEL); if (!diode) return ERR_PTR(-ENOMEM); if (of_property_read_bool(child, "adi,single-ended")) diode->sensor_config = LTC2983_DIODE_SGL(1); if (of_property_read_bool(child, "adi,three-conversion-cycles")) diode->sensor_config |= LTC2983_DIODE_3_CONV_CYCLE(1); if (of_property_read_bool(child, "adi,average-on")) diode->sensor_config |= LTC2983_DIODE_AVERAGE_ON(1); /* validate channel index */ if (!(diode->sensor_config & LTC2983_DIODE_DIFF_MASK) && sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) { dev_err(&st->spi->dev, "Invalid chann:%d for differential thermistor", sensor->chan); return ERR_PTR(-EINVAL); } /* set common parameters */ diode->sensor.fault_handler = ltc2983_common_fault_handler; diode->sensor.assign_chan = ltc2983_diode_assign_chan; ret = of_property_read_u32(child, "adi,excitation-current-microamp", &excitation_current); if (!ret) { switch (excitation_current) { case 10: diode->excitation_current = 0x00; break; case 20: diode->excitation_current = 0x01; break; case 40: diode->excitation_current = 0x02; break; case 80: diode->excitation_current = 0x03; break; default: dev_err(&st->spi->dev, "Invalid value for excitation current(%u)", excitation_current); return ERR_PTR(-EINVAL); } } of_property_read_u32(child, "adi,ideal-factor-value", &temp); /* 2^20 resolution */ diode->ideal_factor_value = __convert_to_raw(temp, 1048576); return &diode->sensor; } static struct ltc2983_sensor *ltc2983_r_sense_new(struct device_node *child, struct ltc2983_data *st, const struct ltc2983_sensor *sensor) { struct ltc2983_rsense *rsense; int ret; u32 temp; rsense = devm_kzalloc(&st->spi->dev, sizeof(*rsense), GFP_KERNEL); if (!rsense) return ERR_PTR(-ENOMEM); /* validate channel index */ if (sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) { dev_err(&st->spi->dev, "Invalid chann:%d for r_sense", sensor->chan); return ERR_PTR(-EINVAL); } ret = of_property_read_u32(child, "adi,rsense-val-milli-ohms", &temp); if (ret) { dev_err(&st->spi->dev, "Property adi,rsense-val-milli-ohms missing\n"); return ERR_PTR(-EINVAL); } /* * Times 1000 because we have milli-ohms and __convert_to_raw * expects scales of 1000000 which are used for all other * properties. * 2^10 resolution */ rsense->r_sense_val = __convert_to_raw((u64)temp * 1000, 1024); /* set common parameters */ rsense->sensor.assign_chan = ltc2983_r_sense_assign_chan; return &rsense->sensor; } static struct ltc2983_sensor *ltc2983_adc_new(struct device_node *child, struct ltc2983_data *st, const struct ltc2983_sensor *sensor) { struct ltc2983_adc *adc; adc = devm_kzalloc(&st->spi->dev, sizeof(*adc), GFP_KERNEL); if (!adc) return ERR_PTR(-ENOMEM); if (of_property_read_bool(child, "adi,single-ended")) adc->single_ended = true; if (!adc->single_ended && sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) { dev_err(&st->spi->dev, "Invalid chan:%d for differential adc\n", sensor->chan); return ERR_PTR(-EINVAL); } /* set common parameters */ adc->sensor.assign_chan = ltc2983_adc_assign_chan; adc->sensor.fault_handler = ltc2983_common_fault_handler; return &adc->sensor; } static int ltc2983_chan_read(struct ltc2983_data *st, const struct ltc2983_sensor *sensor, int *val) { u32 start_conversion = 0; int ret; unsigned long time; start_conversion = LTC2983_STATUS_START(true); start_conversion |= LTC2983_STATUS_CHAN_SEL(sensor->chan); dev_dbg(&st->spi->dev, "Start conversion on chan:%d, status:%02X\n", sensor->chan, start_conversion); /* start conversion */ ret = regmap_write(st->regmap, LTC2983_STATUS_REG, start_conversion); if (ret) return ret; reinit_completion(&st->completion); /* * wait for conversion to complete. * 300 ms should be more than enough to complete the conversion. * Depending on the sensor configuration, there are 2/3 conversions * cycles of 82ms. */ time = wait_for_completion_timeout(&st->completion, msecs_to_jiffies(300)); if (!time) { dev_warn(&st->spi->dev, "Conversion timed out\n"); return -ETIMEDOUT; } /* read the converted data */ ret = regmap_bulk_read(st->regmap, LTC2983_CHAN_RES_ADDR(sensor->chan), &st->temp, sizeof(st->temp)); if (ret) return ret; *val = __be32_to_cpu(st->temp); if (!(LTC2983_RES_VALID_MASK & *val)) { dev_err(&st->spi->dev, "Invalid conversion detected\n"); return -EIO; } ret = sensor->fault_handler(st, *val); if (ret) return ret; *val = sign_extend32((*val) & LTC2983_DATA_MASK, LTC2983_DATA_SIGN_BIT); return 0; } static int ltc2983_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { struct ltc2983_data *st = iio_priv(indio_dev); int ret; /* sanity check */ if (chan->address >= st->num_channels) { dev_err(&st->spi->dev, "Invalid chan address:%ld", chan->address); return -EINVAL; } switch (mask) { case IIO_CHAN_INFO_RAW: mutex_lock(&st->lock); ret = ltc2983_chan_read(st, st->sensors[chan->address], val); mutex_unlock(&st->lock); return ret ?: IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: switch (chan->type) { case IIO_TEMP: /* value in milli degrees */ *val = 1000; /* 2^10 */ *val2 = 1024; return IIO_VAL_FRACTIONAL; case IIO_VOLTAGE: /* value in millivolt */ *val = 1000; /* 2^21 */ *val2 = 2097152; return IIO_VAL_FRACTIONAL; default: return -EINVAL; } } return -EINVAL; } static int ltc2983_reg_access(struct iio_dev *indio_dev, unsigned int reg, unsigned int writeval, unsigned int *readval) { struct ltc2983_data *st = iio_priv(indio_dev); if (readval) return regmap_read(st->regmap, reg, readval); else return regmap_write(st->regmap, reg, writeval); } static irqreturn_t ltc2983_irq_handler(int irq, void *data) { struct ltc2983_data *st = data; complete(&st->completion); return IRQ_HANDLED; } #define LTC2983_CHAN(__type, index, __address) ({ \ struct iio_chan_spec __chan = { \ .type = __type, \ .indexed = 1, \ .channel = index, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ .address = __address, \ }; \ __chan; \ }) static int ltc2983_parse_dt(struct ltc2983_data *st) { struct device_node *child; struct device *dev = &st->spi->dev; int ret = 0, chan = 0, channel_avail_mask = 0; of_property_read_u32(dev->of_node, "adi,mux-delay-config-us", &st->mux_delay_config); of_property_read_u32(dev->of_node, "adi,filter-notch-freq", &st->filter_notch_freq); st->num_channels = of_get_available_child_count(dev->of_node); st->sensors = devm_kcalloc(dev, st->num_channels, sizeof(*st->sensors), GFP_KERNEL); if (!st->sensors) return -ENOMEM; st->iio_channels = st->num_channels; for_each_available_child_of_node(dev->of_node, child) { struct ltc2983_sensor sensor; ret = of_property_read_u32(child, "reg", &sensor.chan); if (ret) { dev_err(dev, "reg property must given for child nodes\n"); return ret; } /* check if we have a valid channel */ if (sensor.chan < LTC2983_MIN_CHANNELS_NR || sensor.chan > LTC2983_MAX_CHANNELS_NR) { dev_err(dev, "chan:%d must be from 1 to 20\n", sensor.chan); return -EINVAL; } else if (channel_avail_mask & BIT(sensor.chan)) { dev_err(dev, "chan:%d already in use\n", sensor.chan); return -EINVAL; } ret = of_property_read_u32(child, "adi,sensor-type", &sensor.type); if (ret) { dev_err(dev, "adi,sensor-type property must given for child nodes\n"); return ret; } dev_dbg(dev, "Create new sensor, type %u, chann %u", sensor.type, sensor.chan); if (sensor.type >= LTC2983_SENSOR_THERMOCOUPLE && sensor.type <= LTC2983_SENSOR_THERMOCOUPLE_CUSTOM) { st->sensors[chan] = ltc2983_thermocouple_new(child, st, &sensor); } else if (sensor.type >= LTC2983_SENSOR_RTD && sensor.type <= LTC2983_SENSOR_RTD_CUSTOM) { st->sensors[chan] = ltc2983_rtd_new(child, st, &sensor); } else if (sensor.type >= LTC2983_SENSOR_THERMISTOR && sensor.type <= LTC2983_SENSOR_THERMISTOR_CUSTOM) { st->sensors[chan] = ltc2983_thermistor_new(child, st, &sensor); } else if (sensor.type == LTC2983_SENSOR_DIODE) { st->sensors[chan] = ltc2983_diode_new(child, st, &sensor); } else if (sensor.type == LTC2983_SENSOR_SENSE_RESISTOR) { st->sensors[chan] = ltc2983_r_sense_new(child, st, &sensor); /* don't add rsense to iio */ st->iio_channels--; } else if (sensor.type == LTC2983_SENSOR_DIRECT_ADC) { st->sensors[chan] = ltc2983_adc_new(child, st, &sensor); } else { dev_err(dev, "Unknown sensor type %d\n", sensor.type); return -EINVAL; } if (IS_ERR(st->sensors[chan])) { dev_err(dev, "Failed to create sensor %ld", PTR_ERR(st->sensors[chan])); return PTR_ERR(st->sensors[chan]); } /* set generic sensor parameters */ st->sensors[chan]->chan = sensor.chan; st->sensors[chan]->type = sensor.type; channel_avail_mask |= BIT(sensor.chan); chan++; } return 0; } static int ltc2983_setup(struct ltc2983_data *st, bool assign_iio) { u32 iio_chan_t = 0, iio_chan_v = 0, chan, iio_idx = 0; int ret; unsigned long time; /* make sure the device is up */ time = wait_for_completion_timeout(&st->completion, msecs_to_jiffies(250)); if (!time) { dev_err(&st->spi->dev, "Device startup timed out\n"); return -ETIMEDOUT; } st->iio_chan = devm_kzalloc(&st->spi->dev, st->iio_channels * sizeof(*st->iio_chan), GFP_KERNEL); if (!st->iio_chan) return -ENOMEM; ret = regmap_update_bits(st->regmap, LTC2983_GLOBAL_CONFIG_REG, LTC2983_NOTCH_FREQ_MASK, LTC2983_NOTCH_FREQ(st->filter_notch_freq)); if (ret) return ret; ret = regmap_write(st->regmap, LTC2983_MUX_CONFIG_REG, st->mux_delay_config); if (ret) return ret; for (chan = 0; chan < st->num_channels; chan++) { u32 chan_type = 0, *iio_chan; ret = st->sensors[chan]->assign_chan(st, st->sensors[chan]); if (ret) return ret; /* * The assign_iio flag is necessary for when the device is * coming out of sleep. In that case, we just need to * re-configure the device channels. * We also don't assign iio channels for rsense. */ if (st->sensors[chan]->type == LTC2983_SENSOR_SENSE_RESISTOR || !assign_iio) continue; /* assign iio channel */ if (st->sensors[chan]->type != LTC2983_SENSOR_DIRECT_ADC) { chan_type = IIO_TEMP; iio_chan = &iio_chan_t; } else { chan_type = IIO_VOLTAGE; iio_chan = &iio_chan_v; } /* * add chan as the iio .address so that, we can directly * reference the sensor given the iio_chan_spec */ st->iio_chan[iio_idx++] = LTC2983_CHAN(chan_type, (*iio_chan)++, chan); } return 0; } static const struct regmap_range ltc2983_reg_ranges[] = { regmap_reg_range(LTC2983_STATUS_REG, LTC2983_STATUS_REG), regmap_reg_range(LTC2983_TEMP_RES_START_REG, LTC2983_TEMP_RES_END_REG), regmap_reg_range(LTC2983_GLOBAL_CONFIG_REG, LTC2983_GLOBAL_CONFIG_REG), regmap_reg_range(LTC2983_MULT_CHANNEL_START_REG, LTC2983_MULT_CHANNEL_END_REG), regmap_reg_range(LTC2983_MUX_CONFIG_REG, LTC2983_MUX_CONFIG_REG), regmap_reg_range(LTC2983_CHAN_ASSIGN_START_REG, LTC2983_CHAN_ASSIGN_END_REG), regmap_reg_range(LTC2983_CUST_SENS_TBL_START_REG, LTC2983_CUST_SENS_TBL_END_REG), }; static const struct regmap_access_table ltc2983_reg_table = { .yes_ranges = ltc2983_reg_ranges, .n_yes_ranges = ARRAY_SIZE(ltc2983_reg_ranges), }; /* * The reg_bits are actually 12 but the device needs the first *complete* * byte for the command (R/W). */ static const struct regmap_config ltc2983_regmap_config = { .reg_bits = 24, .val_bits = 8, .wr_table = <c2983_reg_table, .rd_table = <c2983_reg_table, .read_flag_mask = GENMASK(1, 0), .write_flag_mask = BIT(1), }; static const struct iio_info ltc2983_iio_info = { .read_raw = ltc2983_read_raw, .debugfs_reg_access = ltc2983_reg_access, }; static int ltc2983_probe(struct spi_device *spi) { struct ltc2983_data *st; struct iio_dev *indio_dev; const char *name = spi_get_device_id(spi)->name; int ret; indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); if (!indio_dev) return -ENOMEM; st = iio_priv(indio_dev); st->regmap = devm_regmap_init_spi(spi, <c2983_regmap_config); if (IS_ERR(st->regmap)) { dev_err(&spi->dev, "Failed to initialize regmap\n"); return PTR_ERR(st->regmap); } mutex_init(&st->lock); init_completion(&st->completion); st->spi = spi; spi_set_drvdata(spi, st); ret = ltc2983_parse_dt(st); if (ret) return ret; /* * let's request the irq now so it is used to sync the device * startup in ltc2983_setup() */ ret = devm_request_irq(&spi->dev, spi->irq, ltc2983_irq_handler, IRQF_TRIGGER_RISING, name, st); if (ret) { dev_err(&spi->dev, "failed to request an irq, %d", ret); return ret; } ret = ltc2983_setup(st, true); if (ret) return ret; indio_dev->dev.parent = &spi->dev; indio_dev->name = name; indio_dev->num_channels = st->iio_channels; indio_dev->channels = st->iio_chan; indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->info = <c2983_iio_info; return devm_iio_device_register(&spi->dev, indio_dev); } static int __maybe_unused ltc2983_resume(struct device *dev) { struct ltc2983_data *st = spi_get_drvdata(to_spi_device(dev)); int dummy; /* dummy read to bring the device out of sleep */ regmap_read(st->regmap, LTC2983_STATUS_REG, &dummy); /* we need to re-assign the channels */ return ltc2983_setup(st, false); } static int __maybe_unused ltc2983_suspend(struct device *dev) { struct ltc2983_data *st = spi_get_drvdata(to_spi_device(dev)); return regmap_write(st->regmap, LTC2983_STATUS_REG, LTC2983_SLEEP); } static SIMPLE_DEV_PM_OPS(ltc2983_pm_ops, ltc2983_suspend, ltc2983_resume); static const struct spi_device_id ltc2983_id_table[] = { { "ltc2983" }, {}, }; MODULE_DEVICE_TABLE(spi, ltc2983_id_table); static const struct of_device_id ltc2983_of_match[] = { { .compatible = "adi,ltc2983" }, {}, }; MODULE_DEVICE_TABLE(of, ltc2983_of_match); static struct spi_driver ltc2983_driver = { .driver = { .name = "ltc2983", .of_match_table = ltc2983_of_match, .pm = <c2983_pm_ops, }, .probe = ltc2983_probe, .id_table = ltc2983_id_table, }; module_spi_driver(ltc2983_driver); MODULE_AUTHOR("Nuno Sa "); MODULE_DESCRIPTION("Analog Devices LTC2983 SPI Temperature sensors"); MODULE_LICENSE("GPL");