fake i2c device scan, allow stimulus

diff --git a/src/adafruit_blinka/microcontroller/fake_mcp2221/i2c.py b/src/adafruit_blinka/microcontroller/fake_mcp2221/i2c.py
index 9b55c683923494f99b8a6fbcdd0e336f307e71d1..5f280513fcb7bf00afe1551e608efdb12ef8e34b 100644 (file)
--- a/src/adafruit_blinka/microcontroller/fake_mcp2221/i2c.py
+++ b/src/adafruit_blinka/microcontroller/fake_mcp2221/i2c.py
@@ -2,6 +2,7 @@
 #
 # SPDX-License-Identifier: MIT
 """I2C Class for MCP2221"""
+import random
 from .fake_mcp2221 import mcp2221
 
 
@@ -10,21 +11,28 @@ class I2C:
 
     def __init__(self, *, frequency=100000):
         self._mcp2221 = mcp2221
-        # self._mcp2221._i2c_configure(frequency)
 
-    def scan(self):
-        """Perform an I2C Device Scan"""
-        # TODO: We need to fake an I2C scan here
-        return self._mcp2221.i2c_scan()
+    def scan(self, address_list = None):
+        """Mocks an I2C scan.
+        If address_list is not provided, this function returns a list of 3 randomly generated I2C addresses from 0x0 to 0x79.
+        For a stimulus-driven test: If address_list is provided, this function returns the provided address_list.
+        """
+        if address_list == None:
+            # Generate a list of 3 randomly generated addresses from 0x0 to 0x79
+            address_list = []
+            for _ in range(3):
+                address_list.append(random.randint(0x0, 0x79))
+            return address_list
+        return address_list
 
     # pylint: disable=unused-argument
     def writeto(self, address, buffer, *, start=0, end=None, stop=True):
         """Write data from the buffer to an address"""
-        #self._mcp2221.i2c_writeto(address, buffer, start=start, end=end)
+        pass
 
     def readfrom_into(self, address, buffer, *, start=0, end=None, stop=True):
         """Read data from an address and into the buffer"""
-        #self._mcp2221.i2c_readfrom_into(address, buffer, start=start, end=end)
+        pass
 
     def writeto_then_readfrom(
         self,
@@ -41,17 +49,6 @@ class I2C:
         """Write data from buffer_out to an address and then
         read data from an address and into buffer_in
         """
-
-        """
-        self._mcp2221.i2c_writeto_then_readfrom(
-            address,
-            buffer_out,
-            buffer_in,
-            out_start=out_start,
-            out_end=out_end,
-            in_start=in_start,
-            in_end=in_end,
-        )
-        """
+        pass
 
     # pylint: enable=unused-argument
\ No newline at end of file