diff --git a/adafruit_ssd1322.py b/adafruit_ssd1322.py
index 6fbc526..7d01723 100644
--- a/adafruit_ssd1322.py
+++ b/adafruit_ssd1322.py
@@ -73,7 +73,7 @@ class SSD1322(displayio.Display):
         (0, 90, 180, 270)
     """
 
-    def __init__(self, bus, **kwargs):
+    def __init__(self, bus: displayio.FourWire, **kwargs) -> None:
         # Patch the init sequence for 32 pixel high displays.
         init_sequence = bytearray(_INIT_SEQUENCE)
         height = kwargs["height"]
@@ -96,7 +96,7 @@ def __init__(self, bus, **kwargs):
         self._is_awake = True  # Display starts in active state (_INIT_SEQUENCE)
 
     @property
-    def is_awake(self):
+    def is_awake(self) -> bool:
         """
         The power state of the display. (read-only)
         `True` if the display is active, `False` if in sleep mode.
@@ -104,7 +104,7 @@ def is_awake(self):
         """
         return self._is_awake
 
-    def sleep(self):
+    def sleep(self) -> None:
         """
         Put display into sleep mode.
         Display uses < 10uA in sleep mode. Display remembers display data and operation mode
@@ -114,7 +114,7 @@ def sleep(self):
             self.bus.send(0xAE, b"")  # 0xAE = display off, sleep mode
             self._is_awake = False
 
-    def wake(self):
+    def wake(self) -> None:
         """
         Wake display from sleep mode
         """