text: /*
   * This file is part of the MicroPython project, http://micropython.org/
   *
   * The MIT License (MIT)
   *
   * Copyright (c) 2021 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
   * 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.
   */
  
  #include "shared-bindings/microcontroller/Pin.h"
  
  #include "peripherals/broadcom/gpio.h"
  
  STATIC bool pin_in_use[BCM_PIN_COUNT];
  STATIC bool never_reset_pin[BCM_PIN_COUNT];
  
  void reset_all_pins(void) {
      for (size_t i = 0; i < BCM_PIN_COUNT; i++) {
          if (never_reset_pin[i]) {
              continue;
          }
          reset_pin_number(i);
      }
  }
  
  void never_reset_pin_number(uint8_t pin_number) {
      never_reset_pin[pin_number] = true;
  }
  
  void reset_pin_number(uint8_t pin_number) {
      gpio_set_function(pin_number, GPIO_FUNCTION_INPUT);
      pin_in_use[pin_number] = false;
      never_reset_pin[pin_number] = false;
      // Set the pull to match the datasheet.
      BP_PULL_Enum pull = BP_PULL_NONE;
      if (pin_number < 9 ||
          (33 < pin_number && pin_number < 37) ||
          pin_number > 45) {
          pull = BP_PULL_UP;
      } else if (pin_number != 28 &&
                 pin_number != 29 &&
                 pin_number != 44 &&
                 pin_number != 45) {
          // Most pins are pulled low so we only exclude the four pins that aren't
          // pulled at all.
          pull = BP_PULL_DOWN;
      }
      gpio_set_pull(pin_number, pull);
  }
  
  void common_hal_never_reset_pin(const mcu_pin_obj_t *pin) {
      never_reset_pin_number(pin->number);
  }
  
  void common_hal_reset_pin(const mcu_pin_obj_t *pin) {
      reset_pin_number(pin->number);
  }
  
  void claim_pin(const mcu_pin_obj_t *pin) {
      pin_in_use[pin->number] = true;
  }
  
  bool pin_number_is_free(uint8_t pin_number) {
      return !pin_in_use[pin_number];
  }
  
  bool common_hal_mcu_pin_is_free(const mcu_pin_obj_t *pin) {
      return pin_number_is_free(pin->number);
  }
  
  uint8_t common_hal_mcu_pin_number(const mcu_pin_obj_t *pin) {
      return pin->number;
  }
  
  void common_hal_mcu_pin_claim(const mcu_pin_obj_t *pin) {
      return claim_pin(pin);
  }
  
  void common_hal_mcu_pin_reset_number(uint8_t pin_no) {
      reset_pin_number(pin_no);
  }
  