Untangle code and remove pylint disables

[Adafruit_Blinka-hackapet.git] / src / adafruit_blinka / microcontroller / mcp2221 / mcp2221.py

diff --git a/src/adafruit_blinka/microcontroller/mcp2221/mcp2221.py b/src/adafruit_blinka/microcontroller/mcp2221/mcp2221.py
index 7b62c3f5c4931a4c9e0eb47bd0714fa966f0f16f..2dcc5394718eb79efd25a5c0706b79187e015b97 100644 (file)
--- a/src/adafruit_blinka/microcontroller/mcp2221/mcp2221.py
+++ b/src/adafruit_blinka/microcontroller/mcp2221/mcp2221.py
@@ -5,6 +5,8 @@
 
 import os
 import time
+import atexit
+
 import hid
 
 # Here if you need it
@@ -54,6 +56,8 @@ class MCP2221:
     def __init__(self):
         self._hid = hid.device()
         self._hid.open(MCP2221.VID, MCP2221.PID)
+        # make sure the device gets closed before exit
+        atexit.register(self.close)
         if MCP2221_RESET_DELAY >= 0:
             self._reset()
         self._gp_config = [0x07] * 4  # "don't care" initial value
@@ -61,6 +65,14 @@ class MCP2221:
             self.gp_set_mode(pin, self.GP_GPIO)  # set to GPIO mode
             self.gpio_set_direction(pin, 1)  # set to INPUT
 
+    def close(self):
+        """Close the hid device. Does nothing if the device is not open."""
+        self._hid.close()
+
+    def __del__(self):
+        # try to close the device before destroying the instance
+        self.close()
+
     def _hid_xfer(self, report, response=True):
         """Perform HID Transfer"""
         # first byte is report ID, which =0 for MCP2221
@@ -121,6 +133,7 @@ class MCP2221:
 
     def _reset(self):
         self._hid_xfer(b"\x70\xAB\xCD\xEF", response=False)
+        self._hid.close()
         time.sleep(MCP2221_RESET_DELAY)
         start = time.monotonic()
         while time.monotonic() - start < 5:
@@ -235,7 +248,7 @@ class MCP2221:
         for _ in range(MCP2221_RETRY_MAX):
             status = self._i2c_status()
             if status[20] & MASK_ADDR_NACK:
-                raise RuntimeError("I2C slave address was NACK'd")
+                raise OSError("I2C slave address was NACK'd")
             usb_cmd_status = status[8]
             if usb_cmd_status == 0:
                 break
@@ -347,7 +360,8 @@ class MCP2221:
             # try a write
             try:
                 self.i2c_writeto(addr, b"\x00")
-            except RuntimeError:  # no reply!
+            except OSError:  # no reply!
+                # We got a NACK, which could be correct
                 continue
             # store if success
             found.append(addr)