run pre-commit

[hackapet/Adafruit_Blinka_Displayio.git] / displayio / fourwire.py

diff --git a/displayio/fourwire.py b/displayio/fourwire.py
index 5d8a433c5de7d564bedd7904cbb58626e3bd4de4..47299e03056f2fb3632899ac3ef56ea743aafde5 100644 (file)
--- a/displayio/fourwire.py
+++ b/displayio/fourwire.py
@@ -1,24 +1,6 @@
-# The MIT License (MIT)
+# SPDX-FileCopyrightText: 2020 Melissa LeBlanc-Williams for Adafruit Industries
 #
-# Copyright (c) 2020 Melissa LeBlanc-Williams for Adafruit Industries
-#
-# Permission is hereby granted, free of charge, to any person obtaining a copy
-# of this software and associated documentation files (the "Software"), to deal
-# in the Software without restriction, including without limitation the rights
-# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-# copies of the Software, and to permit persons to whom the Software is
-# furnished to do so, subject to the following conditions:
-#
-# The above copyright notice and this permission notice shall be included in
-# all copies or substantial portions of the Software.
-#
-# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-# THE SOFTWARE.
+# SPDX-License-Identifier: MIT
 
 """
 `displayio.fourwire`
@@ -68,9 +50,12 @@ class FourWire:
         first code.py run.
         """
         self._dc = digitalio.DigitalInOut(command)
-        self._dc.switch_to_output()
+        self._dc.switch_to_output(value=False)
         self._chip_select = digitalio.DigitalInOut(chip_select)
         self._chip_select.switch_to_output(value=True)
+        self._frequency = baudrate
+        self._polarity = polarity
+        self._phase = phase
 
         if reset is not None:
             self._reset = digitalio.DigitalInOut(reset)
@@ -78,10 +63,6 @@ class FourWire:
         else:
             self._reset = None
         self._spi = spi_bus
-        while self._spi.try_lock():
-            pass
-        self._spi.configure(baudrate=baudrate, polarity=polarity, phase=phase)
-        self._spi.unlock()
 
     def _release(self):
         self.reset()
@@ -100,16 +81,12 @@ class FourWire:
             time.sleep(0.001)
             self._reset.value = True
             time.sleep(0.001)
-        else:
-            raise RuntimeError("No reset pin defined")
 
     def send(self, is_command, data, *, toggle_every_byte=False):
         """Sends the given command value followed by the full set of data. Display state,
         such as vertical scroll, set via ``send`` may or may not be reset once the code is
         done.
         """
-        while self._spi.try_lock():
-            pass
         self._dc.value = not is_command
         if toggle_every_byte:
             for byte in data:
@@ -119,4 +96,17 @@ class FourWire:
                 self._chip_select.value = False
         else:
             self._spi.write(data)
+
+    def begin_transaction(self):
+        """Begin the SPI transaction by locking, configuring, and setting Chip Select"""
+        while not self._spi.try_lock():
+            pass
+        self._spi.configure(
+            baudrate=self._frequency, polarity=self._polarity, phase=self._phase
+        )
+        self._chip_select.value = False
+
+    def end_transaction(self):
+        """End the SPI transaction by unlocking and setting Chip Select"""
+        self._chip_select.value = True
         self._spi.unlock()