drivers: sensors: Add driver for LM95234 temperature sensor

drivers/sensor/ti/CMakeLists.txt

@@ -8,6 +8,7 @@ add_subdirectory_ifdef(CONFIG_INA219 ina219)
 add_subdirectory_ifdef(CONFIG_INA226 ina226)
 add_subdirectory_ifdef(CONFIG_INA23X ina23x)
 add_subdirectory_ifdef(CONFIG_INA3221 ina3221)
+add_subdirectory_ifdef(CONFIG_LM95234 lm95234)
 add_subdirectory_ifdef(CONFIG_OPT3001 opt3001)
 add_subdirectory_ifdef(CONFIG_TI_HDC ti_hdc)
 add_subdirectory_ifdef(CONFIG_TI_HDC20XX ti_hdc20xx)

drivers/sensor/ti/Kconfig

@@ -8,6 +8,7 @@ source "drivers/sensor/ti/ina219/Kconfig"
 source "drivers/sensor/ti/ina226/Kconfig"
 source "drivers/sensor/ti/ina23x/Kconfig"
 source "drivers/sensor/ti/ina3221/Kconfig"
+source "drivers/sensor/ti/lm95234/Kconfig"
 source "drivers/sensor/ti/opt3001/Kconfig"
 source "drivers/sensor/ti/ti_hdc/Kconfig"
 source "drivers/sensor/ti/ti_hdc20xx/Kconfig"

drivers/sensor/ti/lm95234/CMakeLists.txt

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: Apache-2.0
+
+zephyr_library()
+
+zephyr_library_sources(lm95234.c)

drivers/sensor/ti/lm95234/Kconfig

@@ -0,0 +1,13 @@
+# LM95234 temperature sensor config
+
+# Copyright (c) 2024 Calian Advanced Technologies
+# SPDX-License-Identifier: Apache-2.0
+
+config LM95234
+	bool "LM95234 Temperature Sensor"
+	default y
+	depends on DT_HAS_NATIONAL_LM95234_ENABLED
+	select I2C
+	help
+	  Enable the driver for the LM95234 Quad Remote Diode and Local
+	  Temperature Sensor with SMBus Interface.

drivers/sensor/ti/lm95234/lm95234.c

@@ -0,0 +1,322 @@
+/*
+ * Copyright (c) 2024 Calian Advanced Technologies
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT national_lm95234
+
+#include <zephyr/device.h>
+#include <zephyr/devicetree.h>
+#include <zephyr/drivers/i2c.h>
+#include <zephyr/drivers/sensor.h>
+#include <zephyr/drivers/sensor/lm95234.h>
+#include <zephyr/pm/device.h>
+#include <zephyr/pm/device_runtime.h>
+#include <zephyr/logging/log.h>
+
+LOG_MODULE_REGISTER(LM95234, CONFIG_SENSOR_LOG_LEVEL);
+
+#define LM95234_REG_LOCAL_TEMP_SIGNED_MSB				0x10
+#define LM95234_REG_LOCAL_TEMP_SIGNED_LSB				0x20
+#define LM95234_REG_REMOTE_TEMP_1_SIGNED_MSB				0x11
+#define LM95234_REG_REMOTE_TEMP_1_SIGNED_LSB				0x21
+#define LM95234_REG_REMOTE_TEMP_2_SIGNED_MSB				0x12
+#define LM95234_REG_REMOTE_TEMP_2_SIGNED_LSB				0x22
+#define LM95234_REG_REMOTE_TEMP_3_SIGNED_MSB				0x13
+#define LM95234_REG_REMOTE_TEMP_3_SIGNED_LSB				0x23
+#define LM95234_REG_REMOTE_TEMP_4_SIGNED_MSB				0x14
+#define LM95234_REG_REMOTE_TEMP_4_SIGNED_LSB				0x24
+#define LM95234_REG_REMOTE_TEMP_1_UNSIGNED_MSB				0x19
+#define LM95234_REG_REMOTE_TEMP_1_UNSIGNED_LSB				0x29
+#define LM95234_REG_REMOTE_TEMP_2_UNSIGNED_MSB				0x1a
+#define LM95234_REG_REMOTE_TEMP_2_UNSIGNED_LSB				0x2a
+#define LM95234_REG_REMOTE_TEMP_3_UNSIGNED_MSB				0x1b
+#define LM95234_REG_REMOTE_TEMP_3_UNSIGNED_LSB				0x2b
+#define LM95234_REG_REMOTE_TEMP_4_UNSIGNED_MSB				0x1c
+#define LM95234_REG_REMOTE_TEMP_4_UNSIGNED_LSB				0x2c
+#define LM95234_REG_DIODE_MODEL_SELECT					0x30
+#define LM95234_REG_REMOTE_1_OFFSET					0x31
+#define LM95234_REG_REMOTE_2_OFFSET					0x32
+#define LM95234_REG_REMOTE_3_OFFSET					0x33
+#define LM95234_REG_REMOTE_4_OFFSET					0x34
+#define LM95234_REG_CONFIG						0x03
+#define LM95234_REG_CONV_RATE						0x04
+#define LM95234_REG_CHANNEL_CONV_ENABLE					0x05
+#define LM95234_REG_FILTER_SETTING					0x06
+#define LM95234_REG_ONESHOT						0x0f
+#define LM95234_REG_COMMON_STATUS					0x02
+#define LM95234_REG_STATUS_1						0x07
+#define LM95234_REG_STATUS_2						0x08
+#define LM95234_REG_STATUS_3						0x09
+#define LM95234_REG_STATUS_4						0x0a
+#define LM95234_REG_DIODE_MODEL_STATUS					0x38
+#define LM95234_REG_TCRIT1_MASK						0x0c
+#define LM95234_REG_TCRIT2_MASK						0x0d
+#define LM95234_REG_TCRIT3_MASK						0x0e
+#define LM95234_REG_LOCAL_TCRIT_LIMIT					0x40
+#define LM95234_REG_REMOTE1_TCRIT1_LIMIT				0x41
+#define LM95234_REG_REMOTE2_TCRIT1_LIMIT				0x42
+#define LM95234_REG_REMOTE3_TCRIT_LIMIT					0x43
+#define LM95234_REG_REMOTE4_TCRIT_LIMIT					0x44
+#define LM95234_REG_REMOTE1_TCRIT23_LIMIT				0x49
+#define LM95234_REG_REMOTE2_TCRIT23_LIMIT				0x4a
+#define LM95234_REG_COMMON_TCRIT_HYSTERESIS				0x5a
+#define LM95234_REG_MANUF_ID						0xfe
+#define LM95234_REG_REV_ID						0xff
+
+#define LM95234_MAN_ID							0x01
+#define LM95234_CHIP_ID							0x79
+
+#define LM95234_CONFIG_STANDBY						BIT(6)
+
+struct lm95234_data {
+	/** Temperatures in raw format read from sensor */
+	int32_t local;
+	int32_t remote[4];
+};
+
+struct lm95234_config {
+	struct i2c_dt_spec i2c;
+};
+
+static inline int lm95234_fetch_temp(const struct lm95234_config *cfg, struct lm95234_data *data,
+				     enum sensor_channel chan, int32_t *output)
+{
+	int ret;
+	uint8_t val;
+	int32_t result = 0;
+
+	if (chan != SENSOR_CHAN_AMBIENT_TEMP) {
+		uint16_t temp;
+		int offset = (chan - SENSOR_CHAN_LM95234_REMOTE_TEMP_1);
+
+		ret = i2c_reg_read_byte_dt(&cfg->i2c,
+					   LM95234_REG_REMOTE_TEMP_1_UNSIGNED_MSB + offset, &val);
+		if (ret) {
+			return ret;
+		}
+		temp = val << 8;
+		ret = i2c_reg_read_byte_dt(&cfg->i2c,
+					  LM95234_REG_REMOTE_TEMP_1_UNSIGNED_LSB + offset, &val);
+		if (ret) {
+			return ret;
+		}
+		temp |= val;
+		result = temp;
+	}
+
+	/* Read signed temperature if unsigned temperature is 0, or for local sensor */
+	if (chan == SENSOR_CHAN_AMBIENT_TEMP || result == 0) {
+		int offset = chan == SENSOR_CHAN_AMBIENT_TEMP ? 0 :
+			(chan - SENSOR_CHAN_LM95234_REMOTE_TEMP_1 + 1);
+		int16_t temp;
+
+		ret = i2c_reg_read_byte_dt(&cfg->i2c,
+					  LM95234_REG_LOCAL_TEMP_SIGNED_MSB + offset, &val);
+		if (ret) {
+			return ret;
+		}
+		temp = val << 8;
+		ret = i2c_reg_read_byte_dt(&cfg->i2c,
+					   LM95234_REG_LOCAL_TEMP_SIGNED_LSB + offset, &val);
+		if (ret) {
+			return ret;
+		}
+		temp |= val;
+		result = temp;
+	}
+	*output = result;
+	return 0;
+}
+
+static int lm95234_sample_fetch(const struct device *dev,
+			     enum sensor_channel chan)
+{
+	struct lm95234_data *data = dev->data;
+	const struct lm95234_config *cfg = dev->config;
+	enum pm_device_state pm_state;
+	int ret;
+
+	(void)pm_device_state_get(dev, &pm_state);
+	if (pm_state != PM_DEVICE_STATE_ACTIVE) {
+		ret = -EIO;
+		return ret;
+	}
+
+	switch ((uint32_t)chan) {
+	case SENSOR_CHAN_ALL:
+		ret = lm95234_fetch_temp(cfg, data, SENSOR_CHAN_AMBIENT_TEMP, &data->local);
+		if (ret)
+			return ret;
+		for (int i = 0; i < ARRAY_SIZE(data->remote); i++) {
+			ret = lm95234_fetch_temp(cfg, data,
+						 SENSOR_CHAN_LM95234_REMOTE_TEMP_1 + i,
+						 &data->remote[i]);
+			if (ret)
+				return ret;
+		}
+		break;
+	case SENSOR_CHAN_AMBIENT_TEMP:
+		ret = lm95234_fetch_temp(cfg, data, chan, &data->local);
+		break;
+	case SENSOR_CHAN_LM95234_REMOTE_TEMP_1:
+	case SENSOR_CHAN_LM95234_REMOTE_TEMP_2:
+	case SENSOR_CHAN_LM95234_REMOTE_TEMP_3:
+	case SENSOR_CHAN_LM95234_REMOTE_TEMP_4:
+		ret = lm95234_fetch_temp(cfg, data, chan,
+					 &data->remote[chan - SENSOR_CHAN_LM95234_REMOTE_TEMP_1]);
+		break;
+	default:
+		ret = -ENOTSUP;
+		break;
+	}
+
+	return ret;
+}
+
+static int lm95234_channel_get(const struct device *dev,
+			    enum sensor_channel chan,
+			    struct sensor_value *val)
+{
+	struct lm95234_data *data = dev->data;
+	int32_t raw_temp;
+
+	switch ((uint32_t)chan) {
+	case SENSOR_CHAN_AMBIENT_TEMP:
+		raw_temp = data->local;
+		break;
+	case SENSOR_CHAN_LM95234_REMOTE_TEMP_1:
+	case SENSOR_CHAN_LM95234_REMOTE_TEMP_2:
+	case SENSOR_CHAN_LM95234_REMOTE_TEMP_3:
+	case SENSOR_CHAN_LM95234_REMOTE_TEMP_4:
+		raw_temp = data->remote[chan - SENSOR_CHAN_LM95234_REMOTE_TEMP_1];
+		break;
+	default:
+		return -ENOTSUP;
+	}
+
+	/* Raw data format is 8 bits integer, 5 bits fractional, 3 bits zero */
+	val->val1 = raw_temp / 256;
+	val->val2 = (raw_temp % 256) * 1000000 / 256;
+	return 0;
+}
+
+static const struct sensor_driver_api lm95234_driver_api = {
+	.sample_fetch = lm95234_sample_fetch,
+	.channel_get = lm95234_channel_get,
+};
+
+static int lm95234_init(const struct device *dev)
+{
+	const struct lm95234_config *cfg = dev->config;
+	int ret = 0;
+	uint8_t value, model_select, model_status;
+
+	if (!i2c_is_ready_dt(&cfg->i2c)) {
+		LOG_ERR("I2C dev not ready");
+		return -ENODEV;
+	}
+
+	ret = i2c_reg_read_byte_dt(&cfg->i2c, LM95234_REG_MANUF_ID, &value);
+	if (ret) {
+		LOG_ERR("Could not read manufacturer ID: %d", ret);
+		return ret;
+	}
+	if (value != LM95234_MAN_ID) {
+		LOG_ERR("Invalid manufacturer ID: %02x", value);
+		return -ENODEV;
+	}
+	ret = i2c_reg_read_byte_dt(&cfg->i2c, LM95234_REG_REV_ID, &value);
+	if (ret) {
+		LOG_ERR("Could not read revision ID: %d", ret);
+		return ret;
+	}
+	if (value != LM95234_CHIP_ID) {
+		LOG_ERR("Invalid chip ID: %02x", value);
+		return -ENODEV;
+	}
+	ret = i2c_reg_read_byte_dt(&cfg->i2c, LM95234_REG_CONFIG, &value);
+	if (ret) {
+		LOG_ERR("Could not read config: %d", ret);
+		return ret;
+	}
+	if (value & LM95234_CONFIG_STANDBY) {
+		value &= ~LM95234_CONFIG_STANDBY;
+		ret = i2c_reg_write_byte_dt(&cfg->i2c, LM95234_REG_CONFIG, value);
+		if (ret) {
+			LOG_ERR("Could not write config: %d", ret);
+			return ret;
+		}
+	}
+	ret = i2c_reg_read_byte_dt(&cfg->i2c, LM95234_REG_DIODE_MODEL_SELECT, &model_select);
+	if (ret) {
+		LOG_ERR("Could not read diode model select: %d", ret);
+		return ret;
+	}
+	ret = i2c_reg_read_byte_dt(&cfg->i2c, LM95234_REG_DIODE_MODEL_STATUS, &model_status);
+	if (ret) {
+		LOG_ERR("Could not read diode model status: %d", ret);
+		return ret;
+	}
+	/**
+	 * Check if any remote inputs have a 3904 transistor detected but are not configured
+	 * as such. If so, configure them as 3904 transistors.
+	 */
+	if (model_select & model_status) {
+		model_select &= ~model_status;
+		ret = i2c_reg_write_byte_dt(&cfg->i2c, LM95234_REG_DIODE_MODEL_SELECT,
+					    model_select);
+		if (ret) {
+			LOG_ERR("Could not write diode model select: %d", ret);
+			return ret;
+		}
+	}
+
+#ifdef CONFIG_PM_DEVICE_RUNTIME
+	pm_device_init_suspended(dev);
+
+	ret = pm_device_runtime_enable(dev);
+	if (ret < 0 && ret != -ENOTSUP) {
+		LOG_ERR("Failed to enable runtime power management");
+		return ret;
+	}
+#endif
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_DEVICE
+
+static int lm95234_pm_action(const struct device *dev, enum pm_device_action action)
+{
+	switch (action) {
+	case PM_DEVICE_ACTION_TURN_ON:
+	case PM_DEVICE_ACTION_RESUME:
+	case PM_DEVICE_ACTION_TURN_OFF:
+	case PM_DEVICE_ACTION_SUSPEND:
+		break;
+	default:
+		return -ENOTSUP;
+	}
+
+	return 0;
+}
+
+#endif
+
+#define LM95234_INST(inst)                                     \
+static struct lm95234_data lm95234_data_##inst;                \
+static const struct lm95234_config lm95234_config_##inst = {   \
+	.i2c = I2C_DT_SPEC_INST_GET(inst),                     \
+};                                                             \
+PM_DEVICE_DT_INST_DEFINE(inst, lm95234_pm_action);	       \
+SENSOR_DEVICE_DT_INST_DEFINE(inst, lm95234_init,               \
+			     PM_DEVICE_DT_INST_GET(inst),      \
+			     &lm95234_data_##inst,	       \
+			     &lm95234_config_##inst,           \
+			     POST_KERNEL,                      \
+			     CONFIG_SENSOR_INIT_PRIORITY,      \
+			     &lm95234_driver_api);
+
+DT_INST_FOREACH_STATUS_OKAY(LM95234_INST)

dts/bindings/sensor/national,lm95234.yaml

@@ -0,0 +1,8 @@
+# Copyright (c) 2024 Calian Advanced Technologies
+# SPDX-License-Identifier: Apache-2.0
+
+description: LM95234 Quad Remote Diode and Local Temperature Sensor with SMBus Interface
+
+compatible: "national,lm95234"
+
+include: [sensor-device.yaml, i2c-device.yaml]

include/zephyr/drivers/sensor/lm95234.h

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2024, Calian Advanced Technologies
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef ZEPHYR_INCLUDE_DRIVERS_SENSOR_LM95234_H_
+#define ZEPHYR_INCLUDE_DRIVERS_SENSOR_LM95234_H_
+
+#include <zephyr/drivers/sensor.h>
+
+enum sensor_channel_lm95234 {
+	/* External temperature inputs */
+	SENSOR_CHAN_LM95234_REMOTE_TEMP_1 = SENSOR_CHAN_PRIV_START,
+	SENSOR_CHAN_LM95234_REMOTE_TEMP_2,
+	SENSOR_CHAN_LM95234_REMOTE_TEMP_3,
+	SENSOR_CHAN_LM95234_REMOTE_TEMP_4
+};
+
+#endif /* ZEPHYR_INCLUDE_DRIVERS_SENSOR_LM95234_H_ */

tests/drivers/build_all/sensor/i2c.dtsi

@@ -1055,3 +1055,9 @@ test_i2c_shtc1: shtc1@8e {
 	measure-mode = "low-power";
 	clock-stretching;
 };
+
+test_i2c_lm95234: lm95234@8f {
+	compatible = "national,lm95234";
+	reg = <0x8f>;
+	status = "okay";
+};