From 68e406ee851e2086f445f073368c4b3b46b6281b Mon Sep 17 00:00:00 2001
From: Nick Hehr <headhipster@hipsterbrown.com>
Date: Tue, 31 Dec 2024 14:09:21 -0500
Subject: [PATCH] fix: initialize hardware during reconfigure, move out of
 get_readings (#10)

---
 src/mcp300x.py | 59 +++++++++++++++++++++++++++++++++++---------------
 1 file changed, 41 insertions(+), 18 deletions(-)

diff --git a/src/mcp300x.py b/src/mcp300x.py
index 85ce64d..fb25cc5 100644
--- a/src/mcp300x.py
+++ b/src/mcp300x.py
@@ -1,4 +1,4 @@
-from typing import ClassVar, Mapping, Any, Dict, Optional, List, cast
+from typing import ClassVar, Mapping, Any, Optional
 from typing_extensions import Self
 
 from viam.module.types import Reconfigurable
@@ -17,6 +17,7 @@
 
 LOGGER = getLogger(__name__)
 
+
 class mcp3xxx(Sensor, Reconfigurable):
     # Defines new model's colon-delimited-triplet
     MODEL: ClassVar[Model] = Model(ModelFamily("viamlabs", "sensor"), "mcp300x")
@@ -26,7 +27,9 @@ class mcp3xxx(Sensor, Reconfigurable):
 
     # Constructor
     @classmethod
-    def new(cls, config: ComponentConfig, dependencies: Mapping[ResourceName, ResourceBase]) -> Self:
+    def new(
+        cls, config: ComponentConfig, dependencies: Mapping[ResourceName, ResourceBase]
+    ) -> Self:
         sensor = cls(config.name)
         sensor.reconfigure(config, dependencies)
         return sensor
@@ -41,45 +44,65 @@ def validate(cls, config: ComponentConfig):
             raise NameError("A sensor_pin must be defined")
 
         if channel_map == "":
-            raise NameError("Channel map must be defined, refers to sensor type and which channel it connects to")
+            raise NameError(
+                "Channel map must be defined, refers to sensor type and which channel it connects to"
+            )
 
         return
 
     # Handles attribute reconfiguration
-    def reconfigure(self, config: ComponentConfig, dependencies: Mapping[ResourceName, ResourceBase]):
+    def reconfigure(
+        self, config: ComponentConfig, dependencies: Mapping[ResourceName, ResourceBase]
+    ):
         # Initializes the resource instance
         self.sensor_pin = int(config.attributes.fields["sensor_pin"].number_value)
         self.channel_map = dict(config.attributes.fields["channel_map"].struct_value)
-        LOGGER.info(f"Channel map is {self.channel_map}")
+        LOGGER.debug(f"Channel map is {self.channel_map}")
+
+        if getattr(self, "spi") is not None:
+            self.spi.deinit()
+
+        if getattr(self, "cs") is not None:
+            self.cs.deinit()
+
+        # Sensor Pin Logic
+        # Creates the SPI bus
+        self.spi = busio.SPI(clock=board.SCK, MISO=board.MISO, MOSI=board.MOSI)
+
+        # Creates the cs (chip select) with a gpio pin variable, we are using 24 GPIO 8 (SPI Chip Select 0), so 8 for the config
+        cs_pin = f"D{self.sensor_pin}"
+        self.cs = digitalio.DigitalInOut(getattr(board, cs_pin))
+
+        # Creates the MCP3008 object, works with MCP3002 and MCP3004 since it is all encompassing
+        self.mcp = MCP.MCP3008(self.spi, self.cs)
         return
 
     """ Implements the methods the Viam RDK defines for the Sensor API (rdk:components:sensor) """
+
     # Implements the Viam Sensor API's get_readings() method
     async def get_readings(
-        self, *, extra: Optional[Mapping[str, Any]] = None, timeout: Optional[float] = None, **kwargs
+        self,
+        *,
+        extra: Optional[Mapping[str, Any]] = None,
+        timeout: Optional[float] = None,
+        **kwargs,
     ) -> Mapping[str, Any]:
         """
         Obtains the measurements/data specific to this sensor.
         Returns:
             Mapping[str, Any]: The measurements. Can be of any type.
         """
-        # Sensor Pin Logic
-        # Creates the SPI bus
-        spi = busio.SPI(clock=board.SCK, MISO=board.MISO, MOSI=board.MOSI)
-
-        # Creates the cs (chip select) with a gpio pin variable, we are using 24 GPIO 8 (SPI Chip Select 0), so 8 for the config
-        my_pin = f"D{self.sensor_pin}"
-        cs = digitalio.DigitalInOut(getattr(board, my_pin))
-
-        # Creates the MCP3008 object, works with MCP3002 and MCP3004 since it is all encompassing
-        mcp = MCP.MCP3008(spi, cs)
 
         readings = {}
         # Iterates over values
         for label, channel in self.channel_map.items():
-            LOGGER.info(f"loop channel is {channel} and loop label is {label}")
+            LOGGER.debug(f"loop channel is {channel} and loop label is {label}")
             # Create an analog input channel
             chan = int(channel)
-            readings[label] = mcp.read(chan)
+            readings[label] = self.mcp.read(chan)
 
         return readings
+
+    async def close(self):
+        self.spi.deinit()
+        self.cs.deinit()