gpio.cpp

#include "gpio.hpp"

#include "stm32f3xx.h"

#include <type_traits>
template <typename T>
constexpr auto cast_base(T &&enumstruct) {
	using T_noref = std::remove_reference_t<T>;
	return static_cast<std::underlying_type_t<T_noref>>(enumstruct);
}

uint8_t Gpio::instancesNum = 0;

Gpio::Gpio() {
}

Gpio::Gpio(GPIO_TypeDef *gpio, PinName pin, GpioConfig pc)
	: Instance(gpio), pin(pin), config(pc)
{
	if( ++Gpio::instancesNum == 1 ) {
		Gpio::allGpioInit();
	}

	this->configure(gpio, pin, pc);

}

Gpio::Gpio(GPIO_TypeDef *gpio, PinName pin, GpioConfig::PinMode mode)
	: Instance(gpio), pin(pin)
{
	if( ++Gpio::instancesNum == 1 ) {
		Gpio::allGpioInit();
	}
	this->configure(gpio, pin, mode);
}

void Gpio::configure(GPIO_TypeDef *gpio, PinName pin, GpioConfig pc) {
	this->Instance = gpio;
	this->pin = pin;
	this->config = pc;

	this->Instance->MODER &= ~(GPIO_MODER_MODER0 << (2*pin));
	this->Instance->MODER |= (cast_base(pc.mode) << (2*pin));
	this->Instance->OTYPER &= ~(GPIO_OTYPER_OT_0 << pin);
	this->Instance->OTYPER |= (cast_base(pc.outputtype) << pin);
	this->Instance->OSPEEDR &= ~(GPIO_OSPEEDER_OSPEEDR0 << (2*pin));
	this->Instance->OSPEEDR |= (cast_base(pc.speed) << (2*pin));
	this->Instance->PUPDR &= ~(GPIO_PUPDR_PUPDR0 << (2*pin));
	this->Instance->PUPDR |= (cast_base(pc.pull) << (2*pin));

	if( this->config.mode == GpioConfig::PinMode::ALTERNATE ) {
		if( this->pin <= 7 ) {
			this->Instance->AFR[0] &= ~(GPIO_AFRL_AFRL0_Msk << (pin * 4));
			this->Instance->AFR[0] |= (this->config.alternateFunc << (pin * 4));
		}else{
			this->Instance->AFR[1] &= ~(GPIO_AFRH_AFRH0_Msk << ((pin - 8) * 4));
			this->Instance->AFR[1] |= (this->config.alternateFunc << ((pin - 8) * 4));
		}
	}
}
void Gpio::configure(GPIO_TypeDef *gpio, PinName pin, GpioConfig::PinMode mode) {
	this->Instance = gpio;
	this->pin = pin;
	this->config.mode = mode;

	this->Instance->MODER &= ~(GPIO_MODER_MODER0 << (2*pin));
	this->Instance->MODER |= (cast_base(mode) << (2*pin));
}

void Gpio::setMode(GpioConfig::PinMode mode) {
	this->Instance->MODER &= ~(GPIO_MODER_MODER0 << (2*pin));
	this->Instance->MODER |= (cast_base(mode) << (2*pin));
	this->mode = mode;
}

void Gpio::allGpioInit() {
	RCC->AHBENR |= RCC_AHBENR_GPIOAEN;
	RCC->AHBENR |= RCC_AHBENR_GPIOBEN;
	RCC->AHBENR |= RCC_AHBENR_GPIOCEN;
	RCC->AHBENR |= RCC_AHBENR_GPIODEN;
	RCC->AHBENR |= RCC_AHBENR_GPIOEEN;
	RCC->AHBENR |= RCC_AHBENR_GPIOFEN;

	// ** DO NOT SET THE REGISTERS BELOW **
	// If GPIOA->MODER is set to 0, it causes errors on SWD debugging.
//	GPIOA->MODER = 0;
//	GPIOB->MODER = 0;
//	GPIOC->MODER = 0;
//	GPIOD->MODER = 0;
//	GPIOF->MODER = 0;
}

bool Gpio::getValue() {
	if( this->config.mode == GpioConfig::PinMode::INPUT ) {
		return (this->Instance->IDR >> this->pin) & 0x01;
	}
	//else
	return (this->Instance->ODR >> this->pin) & 0x01;
}

uint8_t Gpio::operator =(bool val) {
	if( val == true ) {
		return (this->Instance->ODR |= (1 << this->pin));
	}else{
		return (this->Instance->ODR &= ~(1 << this->pin));
	}
}

uint8_t Gpio::operator ^(bool val) {
	return this->getValue() ^ val;
}

uint8_t Gpio::operator^=(bool val) {
	if( this->config.mode != GpioConfig::PinMode::GPIO_OUTPUT ) {
		return *this = *this ^ val;
	}
	//else
	return 0;
}