Add support of TCA6408 IO Expander

api_drivers/common_api_drivers/io_expander/tca6408.py

@@ -0,0 +1,85 @@
+# Copyright (c) 2024 - 2025 Kevin G. Schlosser
+
+from micropython import const  # NOQA
+import io_expander_framework
+
+
+EXIO1 = 0x01
+EXIO2 = 0x02
+EXIO3 = 0x03
+EXIO4 = 0x04
+EXIO5 = 0x05
+EXIO6 = 0x06
+EXIO7 = 0x07
+EXIO8 = 0x08
+
+
+_INPUT_PORT_REG = const(0x00)
+_OUTPUT_PORT_REG = const(0x01)
+_POLARITY_INVERSION_REG = const(0x02)
+_CONFIGURATION_REG = const(0x03)
+
+I2C_ADDR = 0x20
+BITS = 8
+
+# 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26 or 0x27
+I2C_TCA6408_ADDR = 0x20
+
+
+class Pin(io_expander_framework.Pin):
+    _config_settings = 0x00
+    _output_states = 0x00
+    _reg_int_pins = []
+
+    @property
+    def __bit(self):
+        return 1 << (self._id - 1)
+
+    def __read_reg(self, reg):
+        self._buf[0] = 0
+        self._buf[1] = 0
+        self._device.read_mem(reg, buf=self._mv)
+        return self._buf[0] << 8 | self._buf[1]
+
+    def __write_reg(self, reg, value):
+        self._buf[0] = value >> 8 & 0xFF
+        self._buf[1] = value & 0xFF
+        self._device.write_mem(reg, buf=self._mv)
+
+    def _set_dir(self, direction):
+        if direction == self.OUT:
+            Pin._config_settings &= ~self.__bit
+        elif direction == self.IN:
+            Pin._config_settings |= self.__bit
+        else:
+            raise ValueError('OPEN_DRAIN is not supported')
+
+        self.__write_reg(_CONFIGURATION_REG, Pin._config_settings)
+
+    def _set_level(self, level):
+        if self._mode == self.OUT:
+            if level:
+                states = Pin._output_states | self.__bit
+            else:
+                states = Pin._output_states & ~self.__bit
+
+            # 0nly set if there is an actual change
+            if states != Pin._output_states:
+                self.__write_reg(_OUTPUT_PORT_REG, Pin._output_states)
+                Pin._output_states = states
+
+    def _get_level(self):
+        if self._mode == self.IN:
+            states = self.__read_reg(_INPUT_PORT_REG)
+        elif self._mode == self.OUT:
+            states = Pin._output_states
+        else:
+            raise ValueError('Unsupported pin mode')
+
+        return int(bool(states & self.__bit))
+
+    def _set_irq(self, handler, trigger):
+        pass
+
+    def _set_pull(self, pull):
+        pass