/* Reflow Oven Controller
 *
 * Copyright (C) 2020  Mario Hüttel <mario.huettel@gmx.net>
 *
 * This file is part of the Reflow Oven Controller Project.
 *
 * The reflow oven controller is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * The Reflow Oven Control Firmware is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with the reflow oven controller project.
 * If not, see <http://www.gnu.org/licenses/>.
 */

#include <stm-periph/uart.h>
#include <stm32/stm32f4xx.h>
#include <stm-periph/rcc-manager.h>
#include <stm-periph/stm32-gpio-macros.h>
#include <stm-periph/dma-ring-buffer.h>
#include <string.h>

int uart_init(struct stm_uart *uart)
{
	int ret_val = 0;
	uint32_t cr3 = 0;
	uint32_t cr1 = 0;

	if (!uart)
		return -1000;

	rcc_manager_enable_clock(uart->rcc_reg, uart->rcc_bit_no);

	/* Reset all config regs */
	uart->uart_dev->CR1 = uart->uart_dev->CR2 = uart->uart_dev->CR3 = 0UL;

	/* Set baud rate */
	uart->uart_dev->BRR = uart->brr_val;

	/* If DMA buffers are present, configure for DMA use */
	if (uart->dma_rx_buff && uart->rx) {
		cr3 |= USART_CR3_DMAR;

		ret_val = dma_ring_buffer_periph_to_mem_initialize(&uart->rx_ring_buff,
								uart->base_dma_num,
								uart->dma_rx_stream,
								uart->rx_buff_count,
								1U,
								uart->dma_rx_buff,
								(char *)&uart->uart_dev->DR,
								uart->dma_rx_trigger_channel);
		if (ret_val)
			return ret_val;
	}

	if (uart->dma_tx_buff && uart->tx) {
		ret_val = dma_ring_buffer_mem_to_periph_initialize(&uart->tx_ring_buff,
							 uart->base_dma_num,
							 uart->dma_tx_stream,
							 uart->tx_buff_count,
							 1U,
							 uart->dma_tx_buff,
							 uart->dma_tx_trigger_channel,
							 (void *)&uart->uart_dev->DR);
		if (ret_val)
			return ret_val;

		cr3 |= USART_CR3_DMAT;
	}
	uart->uart_dev->CR3 = cr3;

	if (uart->tx)
		cr1 |= USART_CR1_TE;
	if (uart->rx)
		cr1 |= USART_CR1_RE;

	/* Enable uart */
	cr1 |= USART_CR1_UE;
	uart->uart_dev->CR1 = cr1;

	return 0;
}

void uart_change_brr(struct stm_uart *uart, uint32_t brr)
{
	if (!uart || !uart->uart_dev)
		return;

	uart->brr_val = brr;
	uart->uart_dev->BRR = brr;
}

void uart_disable(struct stm_uart *uart)
{
	if (!uart)
		return;

	uart->uart_dev->CR1 = 0;
	uart->uart_dev->CR2 = 0;
	uart->uart_dev->CR3 = 0;

	if (uart->rx && uart->dma_rx_buff)
		dma_ring_buffer_periph_to_mem_stop(&uart->rx_ring_buff);

	if (uart->dma_tx_buff && uart->tx)
		dma_ring_buffer_mem_to_periph_stop(&uart->tx_ring_buff);

	rcc_manager_disable_clock(uart->rcc_reg, uart->rcc_bit_no);
}

void uart_send_char(struct stm_uart *uart, char c)
{
	if (!uart || !uart->uart_dev)
		return;

	while(!(uart->uart_dev->SR & USART_SR_TXE));
	uart->uart_dev->DR = c;
}

void uart_send_array(struct stm_uart *uart, const char *data, uint32_t len)
{
	uint32_t i;

	for (i = 0; i < len; i++)
		uart_send_char(uart, data[i]);
}

void uart_send_string(struct stm_uart *uart, const char *string)
{
	int i;

	for (i = 0; string[i] != '\0'; i++)
		uart_send_char(uart, string[i]);
}

void uart_send_array_with_dma(struct stm_uart *uart, const char *data, uint32_t len)
{
	if (!uart || !uart->dma_tx_buff)
		return;

	dma_ring_buffer_mem_to_periph_insert_data(&uart->tx_ring_buff, data, len);
}

void uart_send_string_with_dma(struct stm_uart *uart, const char *string)
{
	size_t len;

	len = strlen(string);
	uart_send_array_with_dma(uart, string, (uint32_t)len);
}

int uart_receive_data_with_dma(struct stm_uart *uart, const char **data, size_t *len)
{
	if (!uart)
		return -1000;

	return dma_ring_buffer_periph_to_mem_get_data(&uart->rx_ring_buff, (const volatile void **)data, len);
}

char uart_get_char(struct stm_uart *uart)
{
	if (!uart)
		return 0;
	/* Wait for data to be available */
	while (!(uart->uart_dev->SR & USART_SR_RXNE));

	return (char)uart->uart_dev->DR;
}

int uart_check_rx_avail(struct stm_uart *uart)
{
	if (!uart)
		return 0;

	if (uart->uart_dev->SR & USART_SR_RXNE)
		return 1;
	else
		return 0;
}

void uart_tx_dma_complete_int_callback(struct stm_uart *uart)
{
	if (!uart)
		return;

	dma_ring_buffer_mem_to_periph_int_callback(&uart->tx_ring_buff);
}

size_t uart_dma_tx_queue_avail(struct stm_uart *uart)
{
	size_t fill_level = 0UL;

	if (!uart)
		return 0UL;

	(void)dma_ring_buffer_mem_to_periph_fill_level(&uart->tx_ring_buff, &fill_level);

	return fill_level;
}

size_t uart_dma_rx_queue_avail(struct stm_uart *uart)
{
	size_t fill_level = 0UL;

	if (!uart)
		return 0UL;

	(void)dma_ring_buffer_periph_to_mem_fill_level(&uart->rx_ring_buff, &fill_level);

	return fill_level;
}