Move Raspberry Pi detection out of board.py

.pylintrc

@@ -223,9 +223,7 @@ indent-string='    '
 max-line-length=100
 
 # Maximum number of lines in a module
-#
-# XXX: Reduce this number once Issue 296 is resolved.
-max-module-lines=1050
+max-module-lines=1000
 
 # List of optional constructs for which whitespace checking is disabled. `dict-
 # separator` is used to allow tabulation in dicts, etc.: {1  : 1,\n222: 2}.

adafruit_platformdetect/board.py

@@ -21,15 +21,14 @@
 """
 
 import os
-import re
 
 try:
     from typing import Optional
 except ImportError:
     pass
 
 from adafruit_platformdetect.constants import boards, chips
-
+from adafruit_platformdetect.boards import raspberrypi
 
 __version__ = "0.0.0+auto.0"
 __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_PlatformDetect.git"
@@ -64,7 +63,9 @@ def id(self) -> Optional[str]:
         if chip_id == chips.H3:
             board_id = self._armbian_id() or self._allwinner_variants_id()
         elif chip_id == chips.BCM2XXX:
-            board_id = self._pi_id()
+            from adafruit_platformdetect.boards.raspberrypi import determine_board_id
+
+            board_id = determine_board_id(self.detector)
         elif chip_id == chips.AM625X:
             board_id = self._beaglebone_id()
         elif chip_id == chips.AM33XX:
@@ -198,67 +199,9 @@ def id(self) -> Optional[str]:
 
     # pylint: enable=invalid-name
 
-    def _pi_id(self) -> Optional[str]:
-        """Try to detect id of a Raspberry Pi."""
-        # Check for Pi boards:
-        pi_rev_code = self._pi_rev_code()
-        if pi_rev_code:
-            from adafruit_platformdetect.revcodes import PiDecoder
-
-            try:
-                decoder = PiDecoder(pi_rev_code)
-                model = boards._PI_MODELS[decoder.type_raw]
-                if isinstance(model, dict):
-                    model = model[decoder.revision]
-                return model
-            except ValueError:
-                pass
-        # We may be on a non-Raspbian OS, so try to lazily determine
-        # the version based on `get_device_model`
-        else:
-            pi_model = self.detector.get_device_model()
-            if pi_model:
-                pi_model = pi_model.upper().replace(" ", "_")
-                if "PLUS" in pi_model:
-                    re_model = re.search(r"(RASPBERRY_PI_\d).*([AB]_*)(PLUS)", pi_model)
-                elif "CM" in pi_model:  # untested for Compute Module
-                    re_model = re.search(r"(RASPBERRY_PI_CM)(\d)", pi_model)
-                else:  # untested for non-plus models
-                    re_model = re.search(r"(RASPBERRY_PI_\d).*([AB])", pi_model)
-
-                if re_model:
-                    pi_model = "".join(re_model.groups())
-                    available_models = boards._PI_REV_CODES.keys()
-                    for model in available_models:
-                        if model == pi_model:
-                            return model
-
-        return None
-
     def _pi_rev_code(self) -> Optional[str]:
         """Attempt to find a Raspberry Pi revision code for this board."""
-        # 2708 is Pi 1
-        # 2709 is Pi 2
-        # 2835 is Pi 3 (or greater) on 4.9.x kernel
-        # Anything else is not a Pi.
-        if self.detector.chip.id != chips.BCM2XXX:
-            # Something else, not a Pi.
-            return None
-        rev = self.detector.get_cpuinfo_field("Revision")
-
-        if rev is not None:
-            return rev
-
-        try:
-            with open("/proc/device-tree/system/linux,revision", "rb") as revision:
-                rev_bytes = revision.read()
-
-                if rev_bytes[:1] == b"\x00":
-                    rev_bytes = rev_bytes[1:]
-
-                return rev_bytes.hex()
-        except FileNotFoundError:
-            return None
+        return raspberrypi.determine_rev_code(self.detector)
 
     # pylint: disable=no-self-use
     def _beaglebone_id(self) -> Optional[str]:

adafruit_platformdetect/boards/raspberrypi/__init__.py

@@ -0,0 +1,85 @@
+# SPDX-FileCopyrightText: 2021-2023 Melissa LeBlanc-Williams for Adafruit Industries
+#
+# SPDX-License-Identifier: MIT
+
+"""Identify specific models and revisions of Raspberry Pi boards."""
+import re
+
+import adafruit_platformdetect.constants.boards as board_ids
+import adafruit_platformdetect.constants.chips as chips_ids
+
+try:
+    from typing import Optional, TYPE_CHECKING
+
+    if TYPE_CHECKING:
+        from adafruit_platformdetect import Detector
+except ImportError:
+    pass
+
+
+# pylint: disable=protected-access
+def determine_board_id(detector: "Detector") -> Optional[str]:
+    """Try to detect id of a Raspberry Pi."""
+    # Check for Pi boards:
+    pi_rev_code = determine_rev_code(detector)
+    if pi_rev_code:
+        from adafruit_platformdetect.revcodes import PiDecoder
+
+        try:
+            decoder = PiDecoder(pi_rev_code)
+            model = board_ids._PI_MODELS[decoder.type_raw]
+            if isinstance(model, dict):
+                model = model[decoder.revision]
+            return model
+        except ValueError:
+            pass
+    # We may be on a non-Raspbian OS, so try to lazily determine
+    # the version based on `get_device_model`
+    else:
+        pi_model = detector.get_device_model()
+        if pi_model:
+            pi_model = pi_model.upper().replace(" ", "_")
+            if "PLUS" in pi_model:
+                re_model = re.search(r"(RASPBERRY_PI_\d).*([AB]_*)(PLUS)", pi_model)
+            elif "CM" in pi_model:  # untested for Compute Module
+                re_model = re.search(r"(RASPBERRY_PI_CM)(\d)", pi_model)
+            else:  # untested for non-plus models
+                re_model = re.search(r"(RASPBERRY_PI_\d).*([AB])", pi_model)
+
+            if re_model:
+                pi_model = "".join(re_model.groups())
+                available_models = board_ids._PI_REV_CODES.keys()
+                for model in available_models:
+                    if model == pi_model:
+                        return model
+
+    return None
+
+
+# pylint: enable=protected-access
+
+
+def determine_rev_code(detector: "Detector") -> Optional[str]:
+    """Attempt to find a Raspberry Pi revision code for this board."""
+    # 2708 is Pi 1
+    # 2709 is Pi 2
+    # 2835 is Pi 3 (or greater) on 4.9.x kernel
+    # Anything else is not a Pi.
+    if detector.chip.id != chips_ids.BCM2XXX:
+        # Something else, not a Pi.
+        return None
+    rev = detector.get_cpuinfo_field("Revision")
+
+    if rev is not None:
+        return rev
+
+    try:
+        with open("/proc/device-tree/system/linux,revision", "rb") as revision:
+            rev_bytes = revision.read()
+
+            if rev_bytes[:1] == b"\x00":
+                rev_bytes = rev_bytes[1:]
+
+            return rev_bytes.hex()
+    except FileNotFoundError:
+        return None