Merge pull request #122 from dhalbert/ble-device-no-wait

Do not wait for USB for non-USB HID devices

adafruit_hid/__init__.py

@@ -28,26 +28,32 @@
 
 try:
  from typing import Sequence
- import usb_hid
 except ImportError:
  pass
 
+# usb_hid may not exist on some boards that still provide BLE or other HID devices.
+try:
+ from usb_hid import Device
+except ImportError:
+ Device = None
+
 __version__ = "0.0.0+auto.0"
 __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_HID.git"
 
 
 def find_device(
- devices: Sequence[usb_hid.Device],
+ devices: Sequence[object],
  *,
  usage_page: int,
  usage: int,
  timeout: int = None,
-) -> usb_hid.Device:
+) -> object:
  """Search through the provided sequence of devices to find the one with the matching
  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."""
+ Defaults to None to wait indefinitely.
+ Ignored if device is not a `usb_hid.Device`; it might be BLE, for instance."""
 
  if hasattr(devices, "send_report"):
  devices = [devices] # type: ignore
@@ -63,20 +69,22 @@ def find_device(
  if device is None:
  raise ValueError("Could not find matching HID 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)
- 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
+ # Wait for USB to be connected only if this is a usb_hid.Device.
+ if Device and isinstance(device, 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