diff options
Diffstat (limited to 'drivers/iio')
-rw-r--r-- | drivers/iio/temperature/Kconfig | 11 | ||||
-rw-r--r-- | drivers/iio/temperature/Makefile | 1 | ||||
-rw-r--r-- | drivers/iio/temperature/ltc2983.c | 1557 |
3 files changed, 1569 insertions, 0 deletions
diff --git a/drivers/iio/temperature/Kconfig b/drivers/iio/temperature/Kconfig index 737faa0901fe..e1ccb4003015 100644 --- a/drivers/iio/temperature/Kconfig +++ b/drivers/iio/temperature/Kconfig @@ -4,6 +4,17 @@ # menu "Temperature sensors" +config LTC2983 + tristate "Analog Devices Multi-Sensor Digital Temperature Measurement System" + depends on SPI + select REGMAP_SPI + help + Say yes here to build support for the LTC2983 Multi-Sensor + high accuracy digital temperature measurement system. + + To compile this driver as a module, choose M here: the module + will be called ltc2983. + config MAXIM_THERMOCOUPLE tristate "Maxim thermocouple sensors" depends on SPI diff --git a/drivers/iio/temperature/Makefile b/drivers/iio/temperature/Makefile index baca4776ca0d..d6b850b0cf63 100644 --- a/drivers/iio/temperature/Makefile +++ b/drivers/iio/temperature/Makefile @@ -3,6 +3,7 @@ # Makefile for industrial I/O temperature drivers # +obj-$(CONFIG_LTC2983) += ltc2983.o obj-$(CONFIG_HID_SENSOR_TEMP) += hid-sensor-temperature.o obj-$(CONFIG_MAXIM_THERMOCOUPLE) += maxim_thermocouple.o obj-$(CONFIG_MAX31856) += max31856.o diff --git a/drivers/iio/temperature/ltc2983.c b/drivers/iio/temperature/ltc2983.c new file mode 100644 index 000000000000..ddf47023364b --- /dev/null +++ b/drivers/iio/temperature/ltc2983.c @@ -0,0 +1,1557 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Analog Devices LTC2983 Multi-Sensor Digital Temperature Measurement System + * driver + * + * Copyright 2019 Analog Devices Inc. + */ +#include <linux/bitfield.h> +#include <linux/completion.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/iio/iio.h> +#include <linux/interrupt.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/of_gpio.h> +#include <linux/regmap.h> +#include <linux/spi/spi.h> + +/* 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 { + of_property_read_u32_index(np, propname, index, + (u32 *)&temp); + } + + 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 |