On Mon, 30 Sep 2019 12:42:46 +0200 Nuno Sá <nuno.sa@xxxxxxxxxx> wrote: > The LTC2983 is a Multi-Sensor High Accuracy Digital Temperature > Measurement System. It measures a wide variety of temperature sensors and > digitally outputs the result, in °C or °F, with 0.1°C accuracy and > 0.001°C resolution. It can measure the temperature of all standard > thermocouples (type B,E,J,K,N,S,R,T), standard 2-,3-,4-wire RTDs, > thermistors and diodes. > > Signed-off-by: Nuno Sá <nuno.sa@xxxxxxxxxx> One minor comment inline. I don't see a reason to use a threaded irq to simply set a completion. Just do it with a traditional irq. I suspect the overhead of doing that is probably similar to spinning up the irq thread. Otherwise, I'm happy with this subject to binding review. Thanks, Jonathan > --- > Changes in v2: > * Added some needed blank lines (for readability); > * Allocate iio_chan in the setup() function; > * Rename reset to sleep; > * Remove unneeded dev_dbg calls; > * Remove unneeded line wrapping; > * Remove unneeded comments; > * Remove extend_names. Use the standard ABI; > * Adapt the scales to report in millivolt and milli degrees; > * Adapt the of_property readings to the renaming of the properties; > * For custom thermistors, excitation-current cannot be set to Auto range. > > MAINTAINERS | 7 + > drivers/iio/temperature/Kconfig | 10 + > drivers/iio/temperature/Makefile | 1 + > drivers/iio/temperature/ltc2983.c | 1436 +++++++++++++++++++++++++++++ > 4 files changed, 1454 insertions(+) > create mode 100644 drivers/iio/temperature/ltc2983.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index f0c03740b9fb..14a256e785ca 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -9491,6 +9491,13 @@ S: Maintained > F: Documentation/devicetree/bindings/iio/dac/ltc1660.txt > F: drivers/iio/dac/ltc1660.c > > +LTC2983 IIO TEMPERATURE DRIVER > +M: Nuno Sá <nuno.sa@xxxxxxxxxx> > +W: http://ez.analog.com/community/linux-device-drivers > +L: linux-iio@xxxxxxxxxxxxxxx > +S: Supported > +F: drivers/iio/temperature/ltc2983.c > + > LTC4261 HARDWARE MONITOR DRIVER > M: Guenter Roeck <linux@xxxxxxxxxxxx> > L: linux-hwmon@xxxxxxxxxxxxxxx > diff --git a/drivers/iio/temperature/Kconfig b/drivers/iio/temperature/Kconfig > index 737faa0901fe..04b5a67b593c 100644 > --- a/drivers/iio/temperature/Kconfig > +++ b/drivers/iio/temperature/Kconfig > @@ -4,6 +4,16 @@ > # > menu "Temperature sensors" > > +config LTC2983 > + tristate "Analog Devices Multi-Sensor Digital Temperature Measurement System" > + depends on 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..7c159da9f183 > --- /dev/null > +++ b/drivers/iio/temperature/ltc2983.c > @@ -0,0 +1,1436 @@ > +// 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_THERMISTOR_DIFF_MASK BIT(2) > +#define LTC2983_DIODE_DIFF_MASK BIT(2) > +#define LTC2983_RTD_4_WIRE_MASK BIT(3) > +#define LTC2983_RTD_ROTATION_MASK BIT(1) > +#define LTC2983_RTD_KELVIN_R_SENSE_MASK GENMASK(3, 2) > + > +#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; > + bool temp_farenheit; > + bool sleep; > +}; > + > +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 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; > + > + n_entries = of_property_count_elems_of_size(np, "adi,custom-sensor", > + sizeof(u64)); > + /* 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; > + > + of_property_read_u64_index(np, "adi,custom-sensor", index, > + &temp); > + /* > + * 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) { > + 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); > + } > + > + 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; > + > + thermo = devm_kzalloc(&st->spi->dev, sizeof(*thermo), GFP_KERNEL); > + if (!thermo) > + return ERR_PTR(-ENOMEM); > + > + of_property_read_u32(child, "adi,sensor-config", > + &thermo->sensor_config); > + /* 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) { > + thermo->custom = __ltc2983_custom_sensor_new(st, child, 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; > + > + 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; > + } > + > + of_property_read_u32(child, "adi,sensor-config", &rtd->sensor_config); > + /* > + * 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, 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; > + } > + > + of_property_read_u32(child, "adi,sensor-config", > + &thermistor->sensor_config); > + /* 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) { > + thermistor->custom = __ltc2983_custom_sensor_new(st, child, > + sensor->type == LTC2983_SENSOR_THERMISTOR_STEINHART ? > + true : false, 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); > + > + of_property_read_u32(child, "adi,sensor-config", &diode->sensor_config); > + /* 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; > + u64 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); > + } > + /* get raw value */ > + ret = of_property_read_u64(child, "adi,rsense-val-micro-ohms", &temp); > + if (ret) { > + dev_err(&st->spi->dev, "Property adi,rsense-val-micro-ohms missing\n"); > + return ERR_PTR(-EINVAL); > + } > + > + /* 2^10 resolution */ > + rsense->r_sense_val = __convert_to_raw(temp, 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; > + __be32 temp; > + > + /* > + * Do not allow channel readings if device is in sleep state. > + * A read/write on the spi bus would bring the device prematurely > + * out of sleep. > + */ > + if (st->sleep) > + return -EPERM; > + > + 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), > + &temp, sizeof(temp)); > + if (ret) > + return ret; > + > + *val = __be32_to_cpu(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); > + > + /* check comment in ltc2983_chan_read() */ > + if (st->sleep) > + return -EPERM; > + > + 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); This is a rare case where I'm not sure a threaded irq actually makes sense. We may be better off just doing this in a traditional top half, rather than spinning up a thread just to set 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; > + > + if (!of_property_read_bool(dev->of_node, "adi,temperature-celcius")) > + st->temp_farenheit = true; > + > + 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; > + u32 global_cfg = 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; > + > + global_cfg = LTC2983_NOTCH_FREQ(st->filter_notch_freq); > + global_cfg |= LTC2983_TEMP_UNITS(st->temp_farenheit); > + regmap_write(st->regmap, LTC2983_GLOBAL_CONFIG_REG, global_cfg); > + regmap_write(st->regmap, LTC2983_MUX_CONFIG_REG, st->mux_delay_config); > + > + 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_threaded_irq(&spi->dev, spi->irq, NULL, > + ltc2983_irq_handler, IRQF_ONESHOT | > + 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 ret; > + > + mutex_lock(&st->lock); > + /* dummy read to bring the device out of sleep */ > + regmap_read(st->regmap, LTC2983_STATUS_REG, &ret); > + /* we need to re-assign the channels */ > + ret = ltc2983_setup(st, false); > + st->sleep = false; > + mutex_unlock(&st->lock); > + > + return ret; > +} > + > +static int __maybe_unused ltc2983_suspend(struct device *dev) > +{ > + struct ltc2983_data *st = spi_get_drvdata(to_spi_device(dev)); > + int ret; > + > + mutex_lock(&st->lock); > + ret = regmap_write(st->regmap, LTC2983_STATUS_REG, LTC2983_SLEEP); > + st->sleep = true; > + mutex_unlock(&st->lock); > + > + return ret; > +} > + > +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_id_table); > + > +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 <nuno.sa@xxxxxxxxxx>"); > +MODULE_DESCRIPTION("Analog Devices LTC2983 SPI Temperature sensors"); > +MODULE_LICENSE("GPL");
