* [RESEND PATCH v2 1/2] iio: temperature: Add support for LTC2983
@ 2019-09-30 10:42 Nuno Sá
2019-09-30 10:42 ` [RESEND PATCH v2 2/2] dt-bindings: iio: Add ltc2983 documentation Nuno Sá
2019-10-01 9:03 ` [RESEND PATCH v2 1/2] iio: temperature: Add support for LTC2983 Jonathan Cameron
0 siblings, 2 replies; 6+ messages in thread
From: Nuno Sá @ 2019-09-30 10:42 UTC (permalink / raw)
To: linux-iio, devicetree
Cc: jic23, knaack.h, lars, pmeerw, robh+dt, mark.rutland
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@analog.com>
---
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@analog.com>
+W: http://ez.analog.com/community/linux-device-drivers
+L: linux-iio@vger.kernel.org
+S: Supported
+F: drivers/iio/temperature/ltc2983.c
+
LTC4261 HARDWARE MONITOR DRIVER
M: Guenter Roeck <linux@roeck-us.net>
L: linux-hwmon@vger.kernel.org
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);
+ 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@analog.com>");
+MODULE_DESCRIPTION("Analog Devices LTC2983 SPI Temperature sensors");
+MODULE_LICENSE("GPL");
--
2.23.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [RESEND PATCH v2 2/2] dt-bindings: iio: Add ltc2983 documentation
2019-09-30 10:42 [RESEND PATCH v2 1/2] iio: temperature: Add support for LTC2983 Nuno Sá
@ 2019-09-30 10:42 ` Nuno Sá
2019-10-01 9:16 ` Jonathan Cameron
2019-10-01 9:03 ` [RESEND PATCH v2 1/2] iio: temperature: Add support for LTC2983 Jonathan Cameron
1 sibling, 1 reply; 6+ messages in thread
From: Nuno Sá @ 2019-09-30 10:42 UTC (permalink / raw)
To: linux-iio, devicetree
Cc: jic23, knaack.h, lars, pmeerw, robh+dt, mark.rutland
Document the LTC2983 temperature sensor devicetree bindings.
Signed-off-by: Nuno Sá <nuno.sa@analog.com>
---
Changes in v2:
* Drop maxItems in non-array elements;
* Set adi,mux-delay-config-us instead of adi,mux-delay-config;
* Wrapped lines at 80 char;
* Added comas to enum elements;
* Use real units in adi,excitation-current;
* Moved some enums to minimum and maximum;
* Grouped patternProperties and moved reg property as a generic property.
.../bindings/iio/temperature/adi,ltc2983.yaml | 406 ++++++++++++++++++
MAINTAINERS | 1 +
2 files changed, 407 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
diff --git a/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml b/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
new file mode 100644
index 000000000000..df68b8233e5e
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
@@ -0,0 +1,406 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/temperature/adi,ltc2983.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices LTC2983 Multi-sensor Temperature system
+
+maintainers:
+ - Nuno Sá <nuno.sa@analog.com>
+
+description: |
+ Analog Devices LTC2983 Multi-Sensor Digital Temperature Measurement System
+ https://www.analog.com/media/en/technical-documentation/data-sheets/2983fc.pdf
+
+properties:
+ compatible:
+ enum:
+ - adi,ltc2983
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ adi,temperature-celcius:
+ description:
+ If this property is present, the temperature is reported in Celsius.
+ type: boolean
+
+ adi,mux-delay-config-us:
+ description:
+ The LTC2983 performs 2 or 3 internal conversion cycles per temperature
+ result. Each conversion cycle is performed with different excitation and
+ input multiplexer configurations. Prior to each conversion, these
+ excitation circuits and input switch configurations are changed and an
+ internal 1ms delay ensures settling prior to the conversion cycle in most
+ cases. An extra delay can be configured using this property. The value is
+ rounded to nearest 100us.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - maximum: 255
+
+ adi,filter-notch-freq:
+ description:
+ Set's the default setting of the digital filter. The default is
+ simultaneous 50/60Hz rejection.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - minimum: 0
+ - maximum: 2
+
+ '#address-cells':
+ const: 1
+
+ '#size-cells':
+ const: 0
+
+patternProperties:
+ ".*@([1-9]|1[0-9]|20)$":
+ type: object
+
+ properties:
+ reg:
+ description: |
+ The channel number. It can be connected to one of the 20 channels of
+ the device.
+ minimum: 1
+ maximum: 20
+
+ required:
+ - reg
+
+ patternProperties:
+ "^thermocouple@.*":
+ type: object
+ description: |
+ Represents a thermocouple sensor which is connected to one of the device
+ channels.
+
+ properties:
+ adi,sensor-type:
+ description: |
+ Identifies the type of thermocouple connected to the device.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - minimum: 1
+ - maximum: 8
+
+ adi,sensor-config:
+ description: |
+ Raw value which set's the sensor configuration. Look at table 14
+ of the datasheet for how to set this value for thermocouples.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - minimum: 1
+ - maximun: 15
+
+ adi,cold-junction-handle:
+ description: |
+ Phandle which points to a sensor object responsible for measuring
+ the thermocouple cold junction temperature.
+ $ref: "/schemas/types.yaml#/definitions/phandle"
+
+ adi,custom-sensor:
+ description: |
+ This is a table, where each entry should be a pair of
+ voltage(mv)-temperature(K). The entries must be given in nv and uK
+ so that, the original values must be multiplied by 1000000. For
+ more details look at table 69 and 70.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/int64-array
+ - minItems: 6
+ - maxItems: 128
+
+ required:
+ - adi,sensor-type
+
+ "^diode@.*":
+ type: object
+ description: |
+ Represents a diode sensor which is connected to one of the device
+ channels.
+
+ properties:
+ adi,sensor-type:
+ description: Identifies the sensor as a diode.
+ const: 28
+
+ adi,sensor-config:
+ description: |
+ Raw value which set's the sensor configuration. Look at table 17
+ of the datasheet for how to set this value for diodes.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - minimum: 0
+ - maximum: 7
+
+ adi,excitation-current-microamp:
+ description: |
+ This property controls the magnitude of the excitation current
+ applied to the diode. Depending on the number of conversions
+ cycles, this property will assume different predefined values on
+ each cycle. Just set the value of the first cycle (1l).
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - enum: [10, 20, 40, 80]
+
+ adi,ideal-factor-value:
+ description: |
+ This property sets the diode ideality factor. The real value must
+ be multiplied by 1000000 to remove the fractional part. For more
+ information look at table 20 of the datasheet.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+
+ required:
+ - adi,sensor-type
+
+ "^rtd@.*":
+ type: object
+ description: |
+ Represents a rtd sensor which is connected to one of the device channels.
+
+ properties:
+ reg:
+ minimum: 2
+
+ adi,sensor-type:
+ description: Identifies the type of RTD connected to the device.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - minimum: 10
+ - maximum: 17
+
+ adi,rsense-handle:
+ description: |
+ Phandle pointing to a rsense object associated with this RTD.
+ $ref: "/schemas/types.yaml#/definitions/phandle"
+
+ adi,sensor-config:
+ description: |
+ Raw value which set's the sensor configuration. Look at table 28
+ of the datasheet for how to set this value for RTD's.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - enum: [0, 1, 4, 5, 8, 9, 10, 12, 13, 14]
+
+ adi,excitation-current-microamp:
+ description: |
+ This property controls the magnitude of the excitation current
+ applied to the RTD.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - enum: [5, 10, 25, 50, 100, 250, 500, 1000]
+
+ adi,rtd-curve:
+ description: |
+ This property set the RTD curve used and the corresponding
+ Callendar-VanDusen constants. Look at table 30 of the datasheet.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - minimum: 0
+ - maximum: 3
+
+ adi,custom-sensor:
+ description: |
+ This is a table, where each entry should be a pair of
+ resistance(ohm)-temperature(K). The entries added here are in uohm
+ and uK. For more details values look at table 74 and 75.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint64-array
+ - minItems: 6
+ - maxItems: 128
+
+ required:
+ - adi,sensor-type
+ - adi,rsense-handle
+
+ "^thermistor@.*":
+ type: object
+ description: |
+ Represents a thermistor sensor which is connected to one of the device
+ channels.
+
+ properties:
+ adi,sensor-type:
+ description: |
+ Identifies the type of thermistor connected to the
+ device.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - minimum: 19
+ - maximum: 25
+
+ adi,rsense-handle:
+ description: |
+ Phandle pointing to a rsense object associated with this
+ thermistor.
+ $ref: "/schemas/types.yaml#/definitions/phandle"
+
+ adi,sensor-config:
+ description: |
+ Raw value which set's the sensor configuration. Look at table 52
+ of the datasheet for how to set this value for thermistors.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - minimum: 0
+ - maximum: 4
+
+ adi,excitation-current-nanoamp:
+ description: |
+ This property controls the magnitude of the excitation current
+ applied to the thermistor. Value 0 set's the sensor in auto-range
+ mode.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - enum: [0, 250, 500, 1000, 5000, 10000, 25000, 50000, 100000,
+ 250000, 500000, 1000000]
+
+ adi,custom-sensor:
+ description: |
+ This is a table, where each entry should be a pair of
+ resistance(ohm)-temperature(K). The entries added here are in uohm
+ and uK only for custom thermistors. For more details look at table
+ 78 and 79. Steinhart-Hart coefficients are also supported and can
+ be programmed into the device memory using this property. For
+ Steinhart sensors, this table has a constant size of 6 entries
+ (defining the coefficients) and the values are given in the raw
+ format. Look at table 82 for more information.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint64-array
+ - minItems: 6
+ - maxItems: 128
+
+ required:
+ - adi,sensor-type
+ - adi,rsense-handle
+
+ "^adc@.*":
+ type: object
+ description: Represents a channel which is being used as a direct adc.
+
+ properties:
+ adi,sensor-type:
+ description: Identifies the sensor as a direct adc.
+ const: 30
+
+ adi,single-ended:
+ description: Boolean property which set's the adc as single-ended.
+ type: boolean
+
+ required:
+ - adi,sensor-type
+
+ "^rsense@.*":
+ type: object
+ description: |
+ Represents a rsense which is connected to one of the device channels.
+ Rsense are used by thermistors and RTD's.
+
+ properties:
+ reg:
+ minimum: 2
+
+ adi,sensor-type:
+ description: Identifies the sensor as a rsense.
+ const: 29
+
+ adi,rsense-val-micro-ohms:
+ description: |
+ Sets the value of the sense resistor. Look at table 20 of the
+ datasheet for information.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint64
+
+ required:
+ - adi,sensor-type
+ - adi, rsense-val
+
+required:
+ - compatible
+ - reg
+ - interrupts
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+ spi0 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ sensor_ltc2983: ltc2983@0 {
+ compatible = "adi,ltc2983";
+ reg = <0>;
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ adi,temperature-celcius;
+ interrupts = <20 IRQ_TYPE_EDGE_RISING>;
+ interrupt-parent = <&gpio>;
+
+ thermocouple@18 {
+ reg = <18>;
+ adi,sensor-type = <8>; //Type B
+ adi,sensor-config = <1>; //Differential, open-circuit current
+ adi,cold-junction-handle = <&diode5>;
+ };
+
+ diode5: diode@5 {
+ reg = <5>;
+ adi,sensor-type = <28>;
+ };
+
+ rsense2: rsense@2 {
+ reg = <2>;
+ adi,sensor-type = <29>;
+ adi,rsense-val-micro-ohms = /bits/ 64 <1200000000>; //1.2Kohms
+ };
+
+ rtd@14 {
+ reg = <14>;
+ adi,sensor-type = <15>; //PT1000
+ /*2-wire, internal gnd, no current rotation*/
+ adi,sensor-config = <1>;
+ adi,excitation-current = <7>; //500uA
+ adi,rsense-handle = <&rsense2>;
+ };
+
+ adc@10 {
+ reg = <10>;
+ adi,sensor-type = <30>;
+ adi,single-ended;
+ };
+
+ thermistor@12 {
+ reg = <12>;
+ adi,sensor-type = <26>; //Steinhart
+ adi,rsense-handle = <&rsense2>;
+ adi,custom-sensor = /bits/ 64 <0x00F371EC 0x12345678
+ 0x2C0F8733 0x10018C66 0xA0FEACCD
+ 0x90021D99>; //6 entries
+ };
+
+ thermocouple@20 {
+ reg = <20>;
+ adi,sensor-type = <9>; //custom thermocouple
+ adi,sensor-config = <8>; //single-ended
+ adi,custom-sensor = /bits/ 64
+ <(-50220000) 0
+ (-30200000) 99100000
+ (-5300000) 135400000
+ 0 273150000
+ 40200000 361200000
+ 55300000 522100000
+ 88300000 720300000
+ 132200000 811200000
+ 188700000 922500000
+ 460400000 1000000000>; //10 pairs
+ };
+
+ };
+ };
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index 14a256e785ca..f747a9dc27f5 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9497,6 +9497,7 @@ W: http://ez.analog.com/community/linux-device-drivers
L: linux-iio@vger.kernel.org
S: Supported
F: drivers/iio/temperature/ltc2983.c
+F: Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
LTC4261 HARDWARE MONITOR DRIVER
M: Guenter Roeck <linux@roeck-us.net>
--
2.23.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [RESEND PATCH v2 1/2] iio: temperature: Add support for LTC2983
2019-09-30 10:42 [RESEND PATCH v2 1/2] iio: temperature: Add support for LTC2983 Nuno Sá
2019-09-30 10:42 ` [RESEND PATCH v2 2/2] dt-bindings: iio: Add ltc2983 documentation Nuno Sá
@ 2019-10-01 9:03 ` Jonathan Cameron
2019-10-02 12:07 ` Sa, Nuno
1 sibling, 1 reply; 6+ messages in thread
From: Jonathan Cameron @ 2019-10-01 9:03 UTC (permalink / raw)
To: Nuno Sá
Cc: linux-iio, devicetree, knaack.h, lars, pmeerw, robh+dt, mark.rutland
On Mon, 30 Sep 2019 12:42:46 +0200
Nuno Sá <nuno.sa@analog.com> 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@analog.com>
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@analog.com>
> +W: http://ez.analog.com/community/linux-device-drivers
> +L: linux-iio@vger.kernel.org
> +S: Supported
> +F: drivers/iio/temperature/ltc2983.c
> +
> LTC4261 HARDWARE MONITOR DRIVER
> M: Guenter Roeck <linux@roeck-us.net>
> L: linux-hwmon@vger.kernel.org
> 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@analog.com>");
> +MODULE_DESCRIPTION("Analog Devices LTC2983 SPI Temperature sensors");
> +MODULE_LICENSE("GPL");
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [RESEND PATCH v2 2/2] dt-bindings: iio: Add ltc2983 documentation
2019-09-30 10:42 ` [RESEND PATCH v2 2/2] dt-bindings: iio: Add ltc2983 documentation Nuno Sá
@ 2019-10-01 9:16 ` Jonathan Cameron
2019-10-02 12:53 ` Sa, Nuno
0 siblings, 1 reply; 6+ messages in thread
From: Jonathan Cameron @ 2019-10-01 9:16 UTC (permalink / raw)
To: Nuno Sá
Cc: linux-iio, devicetree, knaack.h, lars, pmeerw, robh+dt, mark.rutland
On Mon, 30 Sep 2019 12:42:47 +0200
Nuno Sá <nuno.sa@analog.com> wrote:
> Document the LTC2983 temperature sensor devicetree bindings.
>
> Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Hi Nuno,
A few comments inline. This is a complex one so I'll definitely be
looking for a review from Rob or Mark,
Thanks,
Jonathan
> ---
> Changes in v2:
> * Drop maxItems in non-array elements;
> * Set adi,mux-delay-config-us instead of adi,mux-delay-config;
> * Wrapped lines at 80 char;
> * Added comas to enum elements;
> * Use real units in adi,excitation-current;
> * Moved some enums to minimum and maximum;
> * Grouped patternProperties and moved reg property as a generic property.
>
> .../bindings/iio/temperature/adi,ltc2983.yaml | 406 ++++++++++++++++++
> MAINTAINERS | 1 +
> 2 files changed, 407 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
>
> diff --git a/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml b/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
> new file mode 100644
> index 000000000000..df68b8233e5e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
> @@ -0,0 +1,406 @@
> +# SPDX-License-Identifier: GPL-2.0
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/temperature/adi,ltc2983.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Analog Devices LTC2983 Multi-sensor Temperature system
> +
> +maintainers:
> + - Nuno Sá <nuno.sa@analog.com>
> +
> +description: |
> + Analog Devices LTC2983 Multi-Sensor Digital Temperature Measurement System
> + https://www.analog.com/media/en/technical-documentation/data-sheets/2983fc.pdf
> +
> +properties:
> + compatible:
> + enum:
> + - adi,ltc2983
> +
> + reg:
> + maxItems: 1
> +
> + interrupts:
> + maxItems: 1
> +
> + adi,temperature-celcius:
> + description:
> + If this property is present, the temperature is reported in Celsius.
> + type: boolean
> +
> + adi,mux-delay-config-us:
> + description:
> + The LTC2983 performs 2 or 3 internal conversion cycles per temperature
> + result. Each conversion cycle is performed with different excitation and
> + input multiplexer configurations. Prior to each conversion, these
> + excitation circuits and input switch configurations are changed and an
> + internal 1ms delay ensures settling prior to the conversion cycle in most
> + cases. An extra delay can be configured using this property. The value is
> + rounded to nearest 100us.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - maximum: 255
> +
> + adi,filter-notch-freq:
> + description:
> + Set's the default setting of the digital filter. The default is
> + simultaneous 50/60Hz rejection.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - minimum: 0
> + - maximum: 2
This one is an oddity and you should define what the 3 values mean.
If the sensor had supported no notch rejection at all rather than just
50, 60, 50/60 I would have suggested two bools but as it stands I guess
this will just need to be an enum.
> +
> + '#address-cells':
> + const: 1
> +
> + '#size-cells':
> + const: 0
> +
> +patternProperties:
> + ".*@([1-9]|1[0-9]|20)$":
> + type: object
> +
> + properties:
> + reg:
> + description: |
> + The channel number. It can be connected to one of the 20 channels of
> + the device.
> + minimum: 1
> + maximum: 20
> +
> + required:
> + - reg
> +
> + patternProperties:
> + "^thermocouple@.*":
> + type: object
> + description: |
> + Represents a thermocouple sensor which is connected to one of the device
> + channels.
> +
> + properties:
> + adi,sensor-type:
> + description: |
> + Identifies the type of thermocouple connected to the device.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - minimum: 1
> + - maximum: 8
Meaning of values should be defined...
> +
> + adi,sensor-config:
> + description: |
> + Raw value which set's the sensor configuration. Look at table 14
> + of the datasheet for how to set this value for thermocouples.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - minimum: 1
> + - maximun: 15
Hmm. Whilst there are quite a few things in here, it would be nice to break it up
into human readable elements. It's only 3 things and there are a bunch of don't
care states it seems.
> +
> + adi,cold-junction-handle:
> + description: |
> + Phandle which points to a sensor object responsible for measuring
> + the thermocouple cold junction temperature.
> + $ref: "/schemas/types.yaml#/definitions/phandle"
> +
> + adi,custom-sensor:
> + description: |
> + This is a table, where each entry should be a pair of
> + voltage(mv)-temperature(K). The entries must be given in nv and uK
> + so that, the original values must be multiplied by 1000000. For
> + more details look at table 69 and 70.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/int64-array
> + - minItems: 6
> + - maxItems: 128
> +
> + required:
> + - adi,sensor-type
> +
> + "^diode@.*":
> + type: object
> + description: |
> + Represents a diode sensor which is connected to one of the device
> + channels.
> +
> + properties:
> + adi,sensor-type:
> + description: Identifies the sensor as a diode.
> + const: 28
> +
> + adi,sensor-config:
> + description: |
> + Raw value which set's the sensor configuration. Look at table 17
> + of the datasheet for how to set this value for diodes.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - minimum: 0
> + - maximum: 7
Another one I'd like to see broken up.
> +
> + adi,excitation-current-microamp:
> + description: |
> + This property controls the magnitude of the excitation current
> + applied to the diode. Depending on the number of conversions
> + cycles, this property will assume different predefined values on
> + each cycle. Just set the value of the first cycle (1l).
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - enum: [10, 20, 40, 80]
> +
> + adi,ideal-factor-value:
> + description: |
> + This property sets the diode ideality factor. The real value must
> + be multiplied by 1000000 to remove the fractional part. For more
> + information look at table 20 of the datasheet.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> +
> + required:
> + - adi,sensor-type
> +
> + "^rtd@.*":
> + type: object
> + description: |
> + Represents a rtd sensor which is connected to one of the device channels.
> +
> + properties:
> + reg:
> + minimum: 2
> +
> + adi,sensor-type:
> + description: Identifies the type of RTD connected to the device.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - minimum: 10
> + - maximum: 17
> +
> + adi,rsense-handle:
> + description: |
> + Phandle pointing to a rsense object associated with this RTD.
> + $ref: "/schemas/types.yaml#/definitions/phandle"
> +
> + adi,sensor-config:
> + description: |
> + Raw value which set's the sensor configuration. Look at table 28
> + of the datasheet for how to set this value for RTD's.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - enum: [0, 1, 4, 5, 8, 9, 10, 12, 13, 14]
Another one to break up into it's parts, which would also get rid of the
enum with gaps element.
> +
> + adi,excitation-current-microamp:
> + description: |
> + This property controls the magnitude of the excitation current
> + applied to the RTD.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - enum: [5, 10, 25, 50, 100, 250, 500, 1000]
> +
> + adi,rtd-curve:
> + description: |
> + This property set the RTD curve used and the corresponding
> + Callendar-VanDusen constants. Look at table 30 of the datasheet.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - minimum: 0
> + - maximum: 3
> +
> + adi,custom-sensor:
> + description: |
> + This is a table, where each entry should be a pair of
> + resistance(ohm)-temperature(K). The entries added here are in uohm
> + and uK. For more details values look at table 74 and 75.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint64-array
> + - minItems: 6
> + - maxItems: 128
> +
> + required:
> + - adi,sensor-type
> + - adi,rsense-handle
> +
> + "^thermistor@.*":
> + type: object
> + description: |
> + Represents a thermistor sensor which is connected to one of the device
> + channels.
> +
> + properties:
> + adi,sensor-type:
> + description: |
> + Identifies the type of thermistor connected to the
> + device.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - minimum: 19
> + - maximum: 25
> +
> + adi,rsense-handle:
> + description: |
> + Phandle pointing to a rsense object associated with this
> + thermistor.
> + $ref: "/schemas/types.yaml#/definitions/phandle"
> +
> + adi,sensor-config:
> + description: |
> + Raw value which set's the sensor configuration. Look at table 52
> + of the datasheet for how to set this value for thermistors.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - minimum: 0
> + - maximum: 4
Nasty as value 3 is reserved. So break this one up into it's parts as well.
> +
> + adi,excitation-current-nanoamp:
> + description: |
> + This property controls the magnitude of the excitation current
> + applied to the thermistor. Value 0 set's the sensor in auto-range
> + mode.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + - enum: [0, 250, 500, 1000, 5000, 10000, 25000, 50000, 100000,
> + 250000, 500000, 1000000]
> +
> + adi,custom-sensor:
> + description: |
> + This is a table, where each entry should be a pair of
> + resistance(ohm)-temperature(K). The entries added here are in uohm
> + and uK only for custom thermistors. For more details look at table
> + 78 and 79. Steinhart-Hart coefficients are also supported and can
> + be programmed into the device memory using this property. For
> + Steinhart sensors, this table has a constant size of 6 entries
> + (defining the coefficients) and the values are given in the raw
> + format. Look at table 82 for more information.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint64-array
> + - minItems: 6
> + - maxItems: 128
> +
> + required:
> + - adi,sensor-type
> + - adi,rsense-handle
> +
> + "^adc@.*":
> + type: object
> + description: Represents a channel which is being used as a direct adc.
> +
> + properties:
> + adi,sensor-type:
> + description: Identifies the sensor as a direct adc.
> + const: 30
> +
> + adi,single-ended:
> + description: Boolean property which set's the adc as single-ended.
> + type: boolean
> +
> + required:
> + - adi,sensor-type
> +
> + "^rsense@.*":
> + type: object
> + description: |
> + Represents a rsense which is connected to one of the device channels.
> + Rsense are used by thermistors and RTD's.
> +
> + properties:
> + reg:
> + minimum: 2
> +
> + adi,sensor-type:
> + description: Identifies the sensor as a rsense.
> + const: 29
> +
> + adi,rsense-val-micro-ohms:
> + description: |
> + Sets the value of the sense resistor. Look at table 20 of the
> + datasheet for information.
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint64
> +
> + required:
> + - adi,sensor-type
> + - adi, rsense-val
> +
> +required:
> + - compatible
> + - reg
> + - interrupts
> +
> +examples:
> + - |
> + #include <dt-bindings/interrupt-controller/irq.h>
> + spi0 {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + sensor_ltc2983: ltc2983@0 {
> + compatible = "adi,ltc2983";
> + reg = <0>;
> +
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + adi,temperature-celcius;
> + interrupts = <20 IRQ_TYPE_EDGE_RISING>;
> + interrupt-parent = <&gpio>;
> +
> + thermocouple@18 {
> + reg = <18>;
> + adi,sensor-type = <8>; //Type B
> + adi,sensor-config = <1>; //Differential, open-circuit current
> + adi,cold-junction-handle = <&diode5>;
> + };
> +
> + diode5: diode@5 {
> + reg = <5>;
> + adi,sensor-type = <28>;
> + };
> +
> + rsense2: rsense@2 {
> + reg = <2>;
> + adi,sensor-type = <29>;
> + adi,rsense-val-micro-ohms = /bits/ 64 <1200000000>; //1.2Kohms
> + };
> +
> + rtd@14 {
> + reg = <14>;
> + adi,sensor-type = <15>; //PT1000
> + /*2-wire, internal gnd, no current rotation*/
> + adi,sensor-config = <1>;
> + adi,excitation-current = <7>; //500uA
> + adi,rsense-handle = <&rsense2>;
> + };
> +
> + adc@10 {
> + reg = <10>;
> + adi,sensor-type = <30>;
> + adi,single-ended;
> + };
> +
> + thermistor@12 {
> + reg = <12>;
> + adi,sensor-type = <26>; //Steinhart
> + adi,rsense-handle = <&rsense2>;
> + adi,custom-sensor = /bits/ 64 <0x00F371EC 0x12345678
> + 0x2C0F8733 0x10018C66 0xA0FEACCD
> + 0x90021D99>; //6 entries
> + };
> +
> + thermocouple@20 {
> + reg = <20>;
> + adi,sensor-type = <9>; //custom thermocouple
> + adi,sensor-config = <8>; //single-ended
> + adi,custom-sensor = /bits/ 64
> + <(-50220000) 0
> + (-30200000) 99100000
> + (-5300000) 135400000
> + 0 273150000
> + 40200000 361200000
> + 55300000 522100000
> + 88300000 720300000
> + 132200000 811200000
> + 188700000 922500000
> + 460400000 1000000000>; //10 pairs
> + };
> +
> + };
> + };
> +...
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 14a256e785ca..f747a9dc27f5 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -9497,6 +9497,7 @@ W: http://ez.analog.com/community/linux-device-drivers
> L: linux-iio@vger.kernel.org
> S: Supported
> F: drivers/iio/temperature/ltc2983.c
> +F: Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
>
> LTC4261 HARDWARE MONITOR DRIVER
> M: Guenter Roeck <linux@roeck-us.net>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [RESEND PATCH v2 1/2] iio: temperature: Add support for LTC2983
2019-10-01 9:03 ` [RESEND PATCH v2 1/2] iio: temperature: Add support for LTC2983 Jonathan Cameron
@ 2019-10-02 12:07 ` Sa, Nuno
0 siblings, 0 replies; 6+ messages in thread
From: Sa, Nuno @ 2019-10-02 12:07 UTC (permalink / raw)
To: jic23
Cc: robh+dt, mark.rutland, devicetree, knaack.h, linux-iio, pmeerw, lars
On Tue, 2019-10-01 at 10:03 +0100, Jonathan Cameron wrote:
>
> On Mon, 30 Sep 2019 12:42:46 +0200
> Nuno Sá <nuno.sa@analog.com> 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@analog.com>
>
> 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.
ack.
> 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@analog.com>
> > +W: http://ez.analog.com/community/linux-device-drivers
> > +L: linux-iio@vger.kernel.org
> > +S: Supported
> > +F: drivers/iio/temperature/ltc2983.c
> > +
> > LTC4261 HARDWARE MONITOR DRIVER
> > M: Guenter Roeck <linux@roeck-us.net>
> > L: linux-hwmon@vger.kernel.org
> > 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_NOTC
> > H_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_CUST
> > OM_LEN_MASK, x)
> > +
> > +#define LTC2983_CUSTOM_ADDR_MASK GENMASK(11, 6)
> > +#define LTC2983_CUSTOM_ADDR(x) FIELD_PREP(LTC2983_CUST
> > OM_ADDR_MASK, x)
> > +
> > +#define LTC2983_THERMOCOUPLE_CFG_MASK GENMASK(21, 18)
> > +#define LTC2983_THERMOCOUPLE_CFG(x) \
> > + FIELD_PREP(LTC2983_THERMOCOUPLE_CFG_MAS
> > K, 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_DIOD
> > E_CFG_MASK, x)
> > +#define LTC2983_DIODE_EXC_CURRENT_MASK GENMASK(23, 22)
> > +#define LTC2983_DIODE_EXC_CURRENT(x) \
> > + FIELD_PREP(LTC2983_DIODE_EXC_CURRENT_MA
> > SK, x)
> > +#define LTC2983_DIODE_IDEAL_FACTOR_MASK GENMASK(21, 0)
> > +#define LTC2983_DIODE_IDEAL_FACTOR(x) \
> > + FIELD_PREP(LTC2983_DIODE_IDEAL_FACTOR_M
> > ASK, x)
> > +
> > +#define LTC2983_R_SENSE_VAL_MASK GENMASK(26, 0)
> > +#define LTC2983_R_SENSE_VAL(x) FIELD_PREP(LTC2983_R_SE
> > NSE_VAL_MASK, x)
> > +
> > +#define LTC2983_ADC_SINGLE_ENDED_MASK BIT(26)
> > +#define LTC2983_ADC_SINGLE_ENDED(x) \
> > + FIELD_PREP(LTC2983_ADC_SINGLE_ENDED_MAS
> > K, 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_va
> > l);
> > + __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_curr
> > ent);
> > + 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_curr
> > ent);
> > + 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_curr
> > ent);
> > + 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,
> > + &s
> > ensor);
> > + } 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,
> > + &sen
> > sor);
> > + } 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@analog.com>");
> > +MODULE_DESCRIPTION("Analog Devices LTC2983 SPI Temperature
> > sensors");
> > +MODULE_LICENSE("GPL");
--
Analog Devices GmbH Otl-Aicher Strasse 60-64 80807 München
Sitz der Gesellschaft München, Registergericht München HRB 40368,
Geschäftsführer: Stefan Steyerl, Thomas Edward Cribben, Michael Paul
Sondel
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [RESEND PATCH v2 2/2] dt-bindings: iio: Add ltc2983 documentation
2019-10-01 9:16 ` Jonathan Cameron
@ 2019-10-02 12:53 ` Sa, Nuno
0 siblings, 0 replies; 6+ messages in thread
From: Sa, Nuno @ 2019-10-02 12:53 UTC (permalink / raw)
To: jic23
Cc: robh+dt, mark.rutland, devicetree, knaack.h, linux-iio, pmeerw, lars
On Tue, 2019-10-01 at 10:16 +0100, Jonathan Cameron wrote:
>
> On Mon, 30 Sep 2019 12:42:47 +0200
> Nuno Sá <nuno.sa@analog.com> wrote:
>
> > Document the LTC2983 temperature sensor devicetree bindings.
> >
> > Signed-off-by: Nuno Sá <nuno.sa@analog.com>
>
> Hi Nuno,
>
> A few comments inline. This is a complex one so I'll definitely be
> looking for a review from Rob or Mark,
>
> Thanks,
>
> Jonathan
>
> > ---
> > Changes in v2:
> > * Drop maxItems in non-array elements;
> > * Set adi,mux-delay-config-us instead of adi,mux-delay-config;
> > * Wrapped lines at 80 char;
> > * Added comas to enum elements;
> > * Use real units in adi,excitation-current;
> > * Moved some enums to minimum and maximum;
> > * Grouped patternProperties and moved reg property as a generic
> > property.
> >
> > .../bindings/iio/temperature/adi,ltc2983.yaml | 406
> > ++++++++++++++++++
> > MAINTAINERS | 1 +
> > 2 files changed, 407 insertions(+)
> > create mode 100644
> > Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
> >
> > diff --git
> > a/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yam
> > l
> > b/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yam
> > l
> > new file mode 100644
> > index 000000000000..df68b8233e5e
> > --- /dev/null
> > +++
> > b/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yam
> > l
> > @@ -0,0 +1,406 @@
> > +# SPDX-License-Identifier: GPL-2.0
> > +%YAML 1.2
> > +---
> > +$id:
> > http://devicetree.org/schemas/iio/temperature/adi,ltc2983.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Analog Devices LTC2983 Multi-sensor Temperature system
> > +
> > +maintainers:
> > + - Nuno Sá <nuno.sa@analog.com>
> > +
> > +description: |
> > + Analog Devices LTC2983 Multi-Sensor Digital Temperature
> > Measurement System
> > +
> > https://www.analog.com/media/en/technical-documentation/data-sheets/2983fc.pdf
> > +
> > +properties:
> > + compatible:
> > + enum:
> > + - adi,ltc2983
> > +
> > + reg:
> > + maxItems: 1
> > +
> > + interrupts:
> > + maxItems: 1
> > +
> > + adi,temperature-celcius:
> > + description:
> > + If this property is present, the temperature is reported in
> > Celsius.
> > + type: boolean
> > +
> > + adi,mux-delay-config-us:
> > + description:
> > + The LTC2983 performs 2 or 3 internal conversion cycles per
> > temperature
> > + result. Each conversion cycle is performed with different
> > excitation and
> > + input multiplexer configurations. Prior to each conversion,
> > these
> > + excitation circuits and input switch configurations are
> > changed and an
> > + internal 1ms delay ensures settling prior to the conversion
> > cycle in most
> > + cases. An extra delay can be configured using this property.
> > The value is
> > + rounded to nearest 100us.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - maximum: 255
> > +
> > + adi,filter-notch-freq:
> > + description:
> > + Set's the default setting of the digital filter. The default
> > is
> > + simultaneous 50/60Hz rejection.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - minimum: 0
> > + - maximum: 2
>
> This one is an oddity and you should define what the 3 values mean.
> If the sensor had supported no notch rejection at all rather than
> just
> 50, 60, 50/60 I would have suggested two bools but as it stands I
> guess
> this will just need to be an enum.
Yes, I guess we need the enum or like it is right know. I will add
meaning to the values.
> > +
> > + '#address-cells':
> > + const: 1
> > +
> > + '#size-cells':
> > + const: 0
> > +
> > +patternProperties:
> > + ".*@([1-9]|1[0-9]|20)$":
> > + type: object
> > +
> > + properties:
> > + reg:
> > + description: |
> > + The channel number. It can be connected to one of the 20
> > channels of
> > + the device.
> > + minimum: 1
> > + maximum: 20
> > +
> > + required:
> > + - reg
> > +
> > + patternProperties:
> > + "^thermocouple@.*":
> > + type: object
> > + description: |
> > + Represents a thermocouple sensor which is connected to
> > one of the device
> > + channels.
> > +
> > + properties:
> > + adi,sensor-type:
> > + description: |
> > + Identifies the type of thermocouple connected to the
> > device.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - minimum: 1
> > + - maximum: 8
>
> Meaning of values should be defined...
ack.
> > +
> > + adi,sensor-config:
> > + description: |
> > + Raw value which set's the sensor configuration. Look
> > at table 14
> > + of the datasheet for how to set this value for
> > thermocouples.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - minimum: 1
> > + - maximun: 15
> Hmm. Whilst there are quite a few things in here, it would be nice
> to break it up
> into human readable elements. It's only 3 things and there are a
> bunch of don't
> care states it seems.
Yes, now that I gave it more thought, I see I was lazy here. I will
replace this property with 2 other properties. A boolean for single-
Ended and another uint32 prop for open-circuit-current. With those 2
properties I can set the sensor-config bits.
> > +
> > + adi,cold-junction-handle:
> > + description: |
> > + Phandle which points to a sensor object responsible
> > for measuring
> > + the thermocouple cold junction temperature.
> > + $ref: "/schemas/types.yaml#/definitions/phandle"
> > +
> > + adi,custom-sensor:
> > + description: |
> > + This is a table, where each entry should be a pair
> > of
> > + voltage(mv)-temperature(K). The entries must be
> > given in nv and uK
> > + so that, the original values must be multiplied by
> > 1000000. For
> > + more details look at table 69 and 70.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/int64-array
> > + - minItems: 6
> > + - maxItems: 128
> > +
> > + required:
> > + - adi,sensor-type
> > +
> > + "^diode@.*":
> > + type: object
> > + description: |
> > + Represents a diode sensor which is connected to one of
> > the device
> > + channels.
> > +
> > + properties:
> > + adi,sensor-type:
> > + description: Identifies the sensor as a diode.
> > + const: 28
> > +
> > + adi,sensor-config:
> > + description: |
> > + Raw value which set's the sensor configuration. Look
> > at table 17
> > + of the datasheet for how to set this value for
> > diodes.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - minimum: 0
> > + - maximum: 7
> Another one I'd like to see broken up.
ack. I can use 3 booleans here.
> > +
> > + adi,excitation-current-microamp:
> > + description: |
> > + This property controls the magnitude of the
> > excitation current
> > + applied to the diode. Depending on the number of
> > conversions
> > + cycles, this property will assume different
> > predefined values on
> > + each cycle. Just set the value of the first cycle
> > (1l).
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - enum: [10, 20, 40, 80]
> > +
> > + adi,ideal-factor-value:
> > + description: |
> > + This property sets the diode ideality factor. The
> > real value must
> > + be multiplied by 1000000 to remove the fractional
> > part. For more
> > + information look at table 20 of the datasheet.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > +
> > + required:
> > + - adi,sensor-type
> > +
> > + "^rtd@.*":
> > + type: object
> > + description: |
> > + Represents a rtd sensor which is connected to one of the
> > device channels.
> > +
> > + properties:
> > + reg:
> > + minimum: 2
> > +
> > + adi,sensor-type:
> > + description: Identifies the type of RTD connected to
> > the device.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - minimum: 10
> > + - maximum: 17
> > +
> > + adi,rsense-handle:
> > + description: |
> > + Phandle pointing to a rsense object associated with
> > this RTD.
> > + $ref: "/schemas/types.yaml#/definitions/phandle"
> > +
> > + adi,sensor-config:
> > + description: |
> > + Raw value which set's the sensor configuration. Look
> > at table 28
> > + of the datasheet for how to set this value for
> > RTD's.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - enum: [0, 1, 4, 5, 8, 9, 10, 12, 13, 14]
>
> Another one to break up into it's parts, which would also get rid of
> the
> enum with gaps element.
Will do that.
>
> > +
> > + adi,excitation-current-microamp:
> > + description: |
> > + This property controls the magnitude of the
> > excitation current
> > + applied to the RTD.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - enum: [5, 10, 25, 50, 100, 250, 500, 1000]
> > +
> > + adi,rtd-curve:
> > + description: |
> > + This property set the RTD curve used and the
> > corresponding
> > + Callendar-VanDusen constants. Look at table 30 of
> > the datasheet.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - minimum: 0
> > + - maximum: 3
> > +
> > + adi,custom-sensor:
> > + description: |
> > + This is a table, where each entry should be a pair
> > of
> > + resistance(ohm)-temperature(K). The entries added
> > here are in uohm
> > + and uK. For more details values look at table 74 and
> > 75.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint64-
> > array
> > + - minItems: 6
> > + - maxItems: 128
> > +
> > + required:
> > + - adi,sensor-type
> > + - adi,rsense-handle
> > +
> > + "^thermistor@.*":
> > + type: object
> > + description: |
> > + Represents a thermistor sensor which is connected to one
> > of the device
> > + channels.
> > +
> > + properties:
> > + adi,sensor-type:
> > + description: |
> > + Identifies the type of thermistor connected to the
> > + device.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - minimum: 19
> > + - maximum: 25
> > +
> > + adi,rsense-handle:
> > + description: |
> > + Phandle pointing to a rsense object associated with
> > this
> > + thermistor.
> > + $ref: "/schemas/types.yaml#/definitions/phandle"
> > +
> > + adi,sensor-config:
> > + description: |
> > + Raw value which set's the sensor configuration. Look
> > at table 52
> > + of the datasheet for how to set this value for
> > thermistors.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - minimum: 0
> > + - maximum: 4
> Nasty as value 3 is reserved. So break this one up into it's parts
> as well.
Arghh, that is obviously a problem. Will do that.
> > +
> > + adi,excitation-current-nanoamp:
> > + description: |
> > + This property controls the magnitude of the
> > excitation current
> > + applied to the thermistor. Value 0 set's the sensor
> > in auto-range
> > + mode.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint32
> > + - enum: [0, 250, 500, 1000, 5000, 10000, 25000,
> > 50000, 100000,
> > + 250000, 500000, 1000000]
> > +
> > + adi,custom-sensor:
> > + description: |
> > + This is a table, where each entry should be a pair
> > of
> > + resistance(ohm)-temperature(K). The entries added
> > here are in uohm
> > + and uK only for custom thermistors. For more details
> > look at table
> > + 78 and 79. Steinhart-Hart coefficients are also
> > supported and can
> > + be programmed into the device memory using this
> > property. For
> > + Steinhart sensors, this table has a constant size of
> > 6 entries
> > + (defining the coefficients) and the values are given
> > in the raw
> > + format. Look at table 82 for more information.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint64-
> > array
> > + - minItems: 6
> > + - maxItems: 128
> > +
> > + required:
> > + - adi,sensor-type
> > + - adi,rsense-handle
> > +
> > + "^adc@.*":
> > + type: object
> > + description: Represents a channel which is being used as a
> > direct adc.
> > +
> > + properties:
> > + adi,sensor-type:
> > + description: Identifies the sensor as a direct adc.
> > + const: 30
> > +
> > + adi,single-ended:
> > + description: Boolean property which set's the adc as
> > single-ended.
> > + type: boolean
> > +
> > + required:
> > + - adi,sensor-type
> > +
> > + "^rsense@.*":
> > + type: object
> > + description: |
> > + Represents a rsense which is connected to one of the
> > device channels.
> > + Rsense are used by thermistors and RTD's.
> > +
> > + properties:
> > + reg:
> > + minimum: 2
> > +
> > + adi,sensor-type:
> > + description: Identifies the sensor as a rsense.
> > + const: 29
> > +
> > + adi,rsense-val-micro-ohms:
> > + description: |
> > + Sets the value of the sense resistor. Look at table
> > 20 of the
> > + datasheet for information.
> > + allOf:
> > + - $ref: /schemas/types.yaml#/definitions/uint64
> > +
> > + required:
> > + - adi,sensor-type
> > + - adi, rsense-val
> > +
> > +required:
> > + - compatible
> > + - reg
> > + - interrupts
> > +
> > +examples:
> > + - |
> > + #include <dt-bindings/interrupt-controller/irq.h>
> > + spi0 {
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > +
> > + sensor_ltc2983: ltc2983@0 {
> > + compatible = "adi,ltc2983";
> > + reg = <0>;
> > +
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > +
> > + adi,temperature-celcius;
> > + interrupts = <20 IRQ_TYPE_EDGE_RISING>;
> > + interrupt-parent = <&gpio>;
> > +
> > + thermocouple@18 {
> > + reg = <18>;
> > + adi,sensor-type = <8>; //Type B
> > + adi,sensor-config = <1>; //Differential,
> > open-circuit current
> > + adi,cold-junction-handle = <&diode5>;
> > + };
> > +
> > + diode5: diode@5 {
> > + reg = <5>;
> > + adi,sensor-type = <28>;
> > + };
> > +
> > + rsense2: rsense@2 {
> > + reg = <2>;
> > + adi,sensor-type = <29>;
> > + adi,rsense-val-micro-ohms = /bits/ 64
> > <1200000000>; //1.2Kohms
> > + };
> > +
> > + rtd@14 {
> > + reg = <14>;
> > + adi,sensor-type = <15>; //PT1000
> > + /*2-wire, internal gnd, no current
> > rotation*/
> > + adi,sensor-config = <1>;
> > + adi,excitation-current = <7>; //500uA
> > + adi,rsense-handle = <&rsense2>;
> > + };
> > +
> > + adc@10 {
> > + reg = <10>;
> > + adi,sensor-type = <30>;
> > + adi,single-ended;
> > + };
> > +
> > + thermistor@12 {
> > + reg = <12>;
> > + adi,sensor-type = <26>; //Steinhart
> > + adi,rsense-handle = <&rsense2>;
> > + adi,custom-sensor = /bits/ 64 <0x00F371EC
> > 0x12345678
> > + 0x2C0F8733 0x10018C66
> > 0xA0FEACCD
> > + 0x90021D99>; //6 entries
> > + };
> > +
> > + thermocouple@20 {
> > + reg = <20>;
> > + adi,sensor-type = <9>; //custom
> > thermocouple
> > + adi,sensor-config = <8>; //single-ended
> > + adi,custom-sensor = /bits/ 64
> > + <(-50220000) 0
> > + (-30200000) 99100000
> > + (-5300000) 135400000
> > + 0 273150000
> > + 40200000 361200000
> > + 55300000 522100000
> > + 88300000 720300000
> > + 132200000 811200000
> > + 188700000 922500000
> > + 460400000 1000000000>; //10
> > pairs
> > + };
> > +
> > + };
> > + };
> > +...
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 14a256e785ca..f747a9dc27f5 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -9497,6 +9497,7 @@ W:
> > http://ez.analog.com/community/linux-device-drivers
> > L: linux-iio@vger.kernel.org
> > S: Supported
> > F: drivers/iio/temperature/ltc2983.c
> > +F: Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.y
> > aml
> >
> > LTC4261 HARDWARE MONITOR DRIVER
> > M: Guenter Roeck <linux@roeck-us.net>
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2019-10-02 12:54 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-09-30 10:42 [RESEND PATCH v2 1/2] iio: temperature: Add support for LTC2983 Nuno Sá
2019-09-30 10:42 ` [RESEND PATCH v2 2/2] dt-bindings: iio: Add ltc2983 documentation Nuno Sá
2019-10-01 9:16 ` Jonathan Cameron
2019-10-02 12:53 ` Sa, Nuno
2019-10-01 9:03 ` [RESEND PATCH v2 1/2] iio: temperature: Add support for LTC2983 Jonathan Cameron
2019-10-02 12:07 ` Sa, Nuno
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.