drivers/sensors: add Microchip TC74 temperature sensor driver

Documentation/components/drivers/special/sensors.rst

@@ -37,6 +37,7 @@ tool for monitoring sensor activity at runtime.
     sensors/nau7802.rst
     sensors/qmi8658.rst
     sensors/sht4x.rst
+    sensors/tc74.rst
     sensors/tmp112.rst
     sensors/lsm6dso32.rst
     sensors/lsm6ds3trc.rst

Documentation/components/drivers/special/sensors/sensors_uorb.rst

@@ -557,6 +557,7 @@ Implemented Drivers
 - :doc:`nau7802`
 - :doc:`qmi8658`
 - :doc:`sht4x`
+- :doc:`tc74`
 - :doc:`tmp112`
 - :doc:`lsm6dso32`
 - :doc:`lsm6ds3trc`

Documentation/components/drivers/special/sensors/tc74.rst

@@ -0,0 +1,46 @@
+====
+TC74
+====
+
+The TC74 is a Microchip serial digital thermal sensor, specified from
+-40°C to +125°C, with an eight-bit reading of 1°C a count. Factory-programmed
+I2C addresses range from 0x48 through 0x4f (suffixes A0 through A7), allowing
+up to eight parts on the same bus.
+
+This driver uses the :doc:`uorb
+</components/drivers/special/sensors/sensors_uorb>` interface, so the reading
+appears as a topic the common sensor tools can read.
+
+Application Programming Interface
+=================================
+
+The header file for the TC74 driver interface can be included using:
+
+.. code-block:: c
+
+   #include <nuttx/sensors/tc74.h>
+
+Registering the driver creates one topic, ``sensor_temp<n>``, where ``n`` is
+the ``devno`` passed in:
+
+.. code-block:: c
+
+   int tc74_register(int devno, FAR struct i2c_master_s *i2c, uint8_t addr);
+
+For example, a part with address 0x4d (TC74A5) on I2C bus 0, published as
+``sensor_temp0``:
+
+.. code-block:: c
+
+   FAR struct i2c_master_s *i2c = board_i2cbus_initialize(0);
+
+   tc74_register(0, i2c, TC74_ADDR_A5);
+
+Reading
+=======
+
+The driver polls on the low priority work queue at whatever interval a
+consumer asks for. When activated (for example when an application subscribes
+to the sensor topic), the driver wakes the part up from standby mode. When
+deactivated (when all subscribers close the topic), it places the part back
+into low-power standby mode to save energy.

drivers/sensors/CMakeLists.txt

@@ -360,6 +360,10 @@ if(CONFIG_SENSORS)
       endif()
     endif()
 
+    if(CONFIG_SENSORS_TC74)
+      list(APPEND SRCS tc74.c)
+    endif()
+
     # QMI8658 6-axis IMU
 
     if(CONFIG_SENSORS_QMI8658)

drivers/sensors/Kconfig

@@ -2354,6 +2354,24 @@ config SENSORS_TMP112_UORB
 
 endif #SENSORS_TMP112
 
+config SENSORS_TC74
+	bool "Microchip TC74 Temperature Sensor support"
+	default n
+	select I2C
+	---help---
+		Enable driver support for the Microchip TC74 digital temperature sensor.
+
+if SENSORS_TC74
+
+config TC74_I2C_FREQUENCY
+	int "TC74 I2C frequency"
+	default 100000
+	range 1 100000
+	---help---
+		I2C clock frequency for the TC74 sensor. Default is 100 kHz.
+
+endif # SENSORS_TC74
+
 config SENSORS_QMI8658
 	bool "QST QMI8658 6-Axis IMU Sensor support"
 	default n

drivers/sensors/Make.defs

@@ -354,6 +354,10 @@ else
 endif
 endif
 
+ifeq ($(CONFIG_SENSORS_TC74),y)
+  CSRCS += tc74.c
+endif
+
 endif # CONFIG_I2C
 
 # These drivers depend on SPI support