Cleanup display rework for PR.

Fixes #1465. Fixes #1337. Fixes #1168

ports/atmel-samd/boards/feather_m4_express/board.c

@@ -3,7 +3,7 @@
  *
  * The MIT License (MIT)
  *
- * Copyright (c) 2018 Scott Shawcroft for Adafruit Industries
+ * Copyright (c) 2017 Scott Shawcroft 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
@@ -26,13 +26,6 @@
 
 #include "boards/board.h"
 #include "mpconfigboard.h"
-#include "hal/include/hal_gpio.h"
-
-#include "shared-bindings/displayio/Display.h"
-#include "shared-bindings/displayio/FourWire.h"
-#include "shared-module/displayio/mipi_constants.h"
-
-#include "tick.h"
 
 void board_init(void) {
 }

ports/atmel-samd/boards/feather_m4_express/pins.c

@@ -1,6 +1,5 @@
 #include "shared-bindings/board/__init__.h"
 
-#include "boards/board.h"
 #include "supervisor/shared/board_busses.h"
 
 STATIC const mp_rom_map_elem_t board_global_dict_table[] = {

shared-module/displayio/__init__.c

@@ -37,13 +37,9 @@ void displayio_refresh_displays(void) {
                     uint16_t* pixel = &(((uint16_t*)buffer)[index]);
                     *pixel = 0;
 
-                    //if (index == 0) {
-                        if (display->current_group != NULL) {
-                            displayio_group_get_pixel(display->current_group, x, y, pixel);
-                        }
-                    // } else {
-                    //     *pixel = (((uint16_t*)buffer)[0]);
-                    // }
+                    if (display->current_group != NULL) {
+                        displayio_group_get_pixel(display->current_group, x, y, pixel);
+                    }
 
                     index += 1;
                     // The buffer is full, send it.
@@ -189,5 +185,4 @@ void common_hal_displayio_release_displays(void) {
     for (uint8_t i = 0; i < CIRCUITPY_DISPLAY_LIMIT; i++) {
         displays[i].display.base.type = &mp_type_NoneType;
     }
-    // TODO(tannewt): Clear the display datastructures and release everything used.
 }