second round code review changes

Author: Bob Abeles

adafruit_hid/__init__.py

@@ -20,7 +20,11 @@
 # imports
 from __future__ import annotations
 import time
-import supervisor
+
+try:
+    import supervisor
+except ImportError:
+    supervisor = None
 
 try:
     from typing import Sequence
@@ -33,10 +37,18 @@
 
 
 def find_device(
-    devices: Sequence[usb_hid.Device], *, usage_page: int, usage: int, timeout: int
+    devices: Sequence[usb_hid.Device],
+    *,
+    usage_page: int,
+    usage: int,
+    timeout: int = None,
 ) -> usb_hid.Device:
     """Search through the provided sequence of devices to find the one with the matching
-    usage_page and usage. Wait up to timeout seconds for USB to become ready."""
+    usage_page and usage.
+
+    :param timeout: Time in seconds to wait for USB to become ready before timing out.
+    Defaults to None to wait indefinitely."""
+
     if hasattr(devices, "send_report"):
         devices = [devices]  # type: ignore
     device = None
@@ -51,8 +63,20 @@ def find_device(
     if device is None:
         raise ValueError("Could not find matching HID device.")
 
-    for _ in range(timeout):
-        if supervisor.runtime.usb_connected:
-            return device
+    if supervisor is None:
+        # Blinka doesn't have supervisor (see issue Adafruit_Blinka#711), so wait
+        # one second for USB to become ready
         time.sleep(1.0)
-    raise OSError("Failed to initialize HID device. Is USB connected?")
+    elif timeout is None:
+        # default behavior: wait indefinitely for USB to become ready
+        while not supervisor.runtime.usb_connected:
+            time.sleep(1.0)
+    else:
+        # wait up to timeout seconds for USB to become ready
+        for _ in range(timeout):
+            if supervisor.runtime.usb_connected:
+                return device
+            time.sleep(1.0)
+        raise OSError("Failed to initialize HID device. Is USB connected?")
+
+    return device

adafruit_hid/consumer_control.py

@@ -30,10 +30,11 @@
 class ConsumerControl:
     """Send ConsumerControl code reports, used by multimedia keyboards, remote controls, etc."""
 
-    def __init__(self, devices: Sequence[usb_hid.Device], timeout: int = 45) -> None:
+    def __init__(self, devices: Sequence[usb_hid.Device], timeout: int = None) -> None:
         """Create a ConsumerControl object that will send Consumer Control Device HID reports.
 
         :param timeout: Time in seconds to wait for USB to become ready before timing out.
+        Defaults to None to wait indefinitely.
 
         Devices can be a sequence of devices that includes a Consumer Control device or a CC device
         itself. A device is any object that implements ``send_report()``, ``usage_page`` and

adafruit_hid/keyboard.py

@@ -38,10 +38,11 @@ class Keyboard:
 
     # No more than _MAX_KEYPRESSES regular keys may be pressed at once.
 
-    def __init__(self, devices: Sequence[usb_hid.Device], timeout: int = 45) -> None:
+    def __init__(self, devices: Sequence[usb_hid.Device], timeout: int = None) -> None:
         """Create a Keyboard object that will send keyboard HID reports.
 
         :param timeout: Time in seconds to wait for USB to become ready before timing out.
+        Defaults to None to wait indefinitely.
 
         Devices can be a sequence of devices that includes a keyboard device or a keyboard device
         itself. A device is any object that implements ``send_report()``, ``usage_page`` and

adafruit_hid/mouse.py

@@ -27,10 +27,11 @@ class Mouse:
     MIDDLE_BUTTON = 4
     """Middle mouse button."""
 
-    def __init__(self, devices: Sequence[usb_hid.Device], timeout: int = 45) -> None:
+    def __init__(self, devices: Sequence[usb_hid.Device], timeout: int = None) -> None:
         """Create a Mouse object that will send USB mouse HID reports.
 
         :param timeout: Time in seconds to wait for USB to become ready before timing out.
+        Defaults to None to wait indefinitely.
 
         Devices can be a sequence of devices that includes a keyboard device or a keyboard device
         itself. A device is any object that implements ``send_report()``, ``usage_page`` and