/*
* File      : drv_usart.c
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2015, RT-Thread Development Team
*
*  This program is free software; you can redistribute it and/or modify
*  it under the terms of the GNU General Public License as published by
*  the Free Software Foundation; either version 2 of the License, or
*  (at your option) any later version.
*
*  This program 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 this program; if not, write to the Free Software Foundation, Inc.,
*  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Change Logs:
* Date           Author       Notes
* 2009-01-05     Bernard      the first version
* 2015-08-01     xiaonong     the first version for stm32f7xx
* 2016-01-15     ArdaFu       the first version for stm32f4xx with STM32 HAL
*/

#include "drv_usart.h"
#include "board.h"
#include <rtdevice.h>
#include <rthw.h>
#include <rtthread.h>

/* Exported types ------------------------------------------------------------*/
/* Exported constants --------------------------------------------------------*/
/* User can use this section to tailor USARTx/UARTx instance used and associated 
resources */
/* Definition for USARTx clock resources */
#define USARTx                           USART2
#define USARTx_CLK_ENABLE()              __HAL_RCC_USART2_CLK_ENABLE();
#define USARTx_RX_GPIO_CLK_ENABLE()      __HAL_RCC_GPIOA_CLK_ENABLE()
#define USARTx_TX_GPIO_CLK_ENABLE()      __HAL_RCC_GPIOA_CLK_ENABLE() 

#define USARTx_FORCE_RESET()             __HAL_RCC_USART2_FORCE_RESET()
#define USARTx_RELEASE_RESET()           __HAL_RCC_USART2_RELEASE_RESET()

/* Definition for USARTx Pins */
#define USARTx_TX_PIN                    GPIO_PIN_2
#define USARTx_TX_GPIO_PORT              GPIOA  
#define USARTx_TX_AF                     GPIO_AF7_USART2
#define USARTx_RX_PIN                    GPIO_PIN_3
#define USARTx_RX_GPIO_PORT              GPIOA 
#define USARTx_RX_AF                     GPIO_AF7_USART2

/* STM32 uart driver */
struct drv_uart
{
    UART_HandleTypeDef UartHandle;
    IRQn_Type irq;
};

static rt_err_t drv_configure(struct rt_serial_device *serial,
struct serial_configure *cfg)
{
    struct drv_uart *uart;

    RT_ASSERT(serial != RT_NULL);
    RT_ASSERT(cfg != RT_NULL);

    uart = (struct drv_uart *)serial->parent.user_data;

    uart->UartHandle.Init.BaudRate   = cfg->baud_rate;
    uart->UartHandle.Init.HwFlowCtl  = UART_HWCONTROL_NONE;
    uart->UartHandle.Init.Mode       = UART_MODE_TX_RX;
    uart->UartHandle.Init.OverSampling = UART_OVERSAMPLING_16;

    switch (cfg->data_bits)
    {
    case DATA_BITS_8:
        uart->UartHandle.Init.WordLength = UART_WORDLENGTH_8B;
        break;
    case DATA_BITS_9:
        uart->UartHandle.Init.WordLength = UART_WORDLENGTH_9B;
        break;
    default:
        uart->UartHandle.Init.WordLength = UART_WORDLENGTH_8B;
        break;
    }
    switch (cfg->stop_bits)
    {
    case STOP_BITS_1:
        uart->UartHandle.Init.StopBits   = UART_STOPBITS_1;
        break;
    case STOP_BITS_2:
        uart->UartHandle.Init.StopBits   = UART_STOPBITS_2;
        break;
    default:
        uart->UartHandle.Init.StopBits   = UART_STOPBITS_1;
        break;
    }
    switch (cfg->parity)
    {
    case PARITY_NONE:
        uart->UartHandle.Init.Parity     = UART_PARITY_NONE;
        break;
    case PARITY_ODD:
        uart->UartHandle.Init.Parity     = UART_PARITY_ODD;
        break;
    case PARITY_EVEN:
        uart->UartHandle.Init.Parity     = UART_PARITY_EVEN;
        break;
    default:
        uart->UartHandle.Init.Parity     = UART_PARITY_NONE;
        break;
    }

    if (HAL_UART_Init(&uart->UartHandle) != HAL_OK)
    {
        return RT_ERROR;
    }

    return RT_EOK;
}

static rt_err_t drv_control(struct rt_serial_device *serial,
int cmd, void *arg)
{
    struct drv_uart *uart;

    RT_ASSERT(serial != RT_NULL);
    uart = (struct drv_uart *)serial->parent.user_data;

    switch (cmd)
    {
    case RT_DEVICE_CTRL_CLR_INT:
        /* disable rx irq */
        NVIC_DisableIRQ(uart->irq);
        /* disable interrupt */
        __HAL_UART_DISABLE_IT(&uart->UartHandle, UART_IT_RXNE);
        break;
    case RT_DEVICE_CTRL_SET_INT:
        /* enable rx irq */
        NVIC_EnableIRQ(uart->irq);
        /* enable interrupt */
        __HAL_UART_ENABLE_IT(&uart->UartHandle, UART_IT_RXNE);
        break;
    }

    return RT_EOK;
}

static int drv_putc(struct rt_serial_device *serial, char c)
{
    struct drv_uart *uart;

    RT_ASSERT(serial != RT_NULL);
    uart = (struct drv_uart *)serial->parent.user_data;
    
    __HAL_UART_CLEAR_FLAG(&(uart->UartHandle), UART_FLAG_TC);
    uart->UartHandle.Instance->DR = c;
    while (__HAL_UART_GET_FLAG(&(uart->UartHandle), UART_FLAG_TC) == RESET);
    return 1;
}

static int drv_getc(struct rt_serial_device *serial)
{
    int ch;
    struct drv_uart *uart;

    RT_ASSERT(serial != RT_NULL);
    uart = (struct drv_uart *)serial->parent.user_data;

    ch = -1;
    if (__HAL_UART_GET_FLAG(&uart->UartHandle, UART_FLAG_RXNE) != RESET) 
        ch = uart->UartHandle.Instance->DR & 0xff;
    return ch;
}

static const struct rt_uart_ops drv_uart_ops =
{
    drv_configure,
    drv_control,
    drv_putc,
    drv_getc,
};

#if defined(RT_USING_UART2)
/* UART1 device driver structure */

static struct drv_uart uart2;
struct rt_serial_device serial2;

void USART2_IRQHandler(void)
{
    struct drv_uart *uart;

    uart = &uart2;
    /* enter interrupt */
    rt_interrupt_enter();

    /* UART in mode Receiver -------------------------------------------------*/
    if ((__HAL_UART_GET_FLAG(&uart->UartHandle, UART_FLAG_RXNE) != RESET) &&
            (__HAL_UART_GET_IT_SOURCE(&uart->UartHandle, UART_IT_RXNE) != RESET))
    {
        rt_hw_serial_isr(&serial2, RT_SERIAL_EVENT_RX_IND);
        /* Clear RXNE interrupt flag */
        __HAL_UART_CLEAR_FLAG(&uart->UartHandle, UART_FLAG_RXNE);
    }
    /* leave interrupt */
    rt_interrupt_leave();
}

#endif /* RT_USING_UART1 */

/**
* @brief UART MSP Initialization
*        This function configures the hardware resources used in this example:
*           - Peripheral's clock enable
*           - Peripheral's GPIO Configuration
*           - NVIC configuration for UART interrupt request enable
* @param huart: UART handle pointer
* @retval None
*/
void HAL_UART_MspInit(UART_HandleTypeDef *huart)
{
    GPIO_InitTypeDef  GPIO_InitStruct;
    if (huart->Instance == USART2)
    {
        /*##-1- Enable peripherals and GPIO Clocks #################################*/
        /* Enable GPIO TX/RX clock */
        USARTx_TX_GPIO_CLK_ENABLE();
        USARTx_RX_GPIO_CLK_ENABLE();

        /* Enable USARTx clock */
        USARTx_CLK_ENABLE(); 

        /*##-2- Configure peripheral GPIO ##########################################*/  
        /* UART TX GPIO pin configuration  */
        GPIO_InitStruct.Pin       = USARTx_TX_PIN;
        GPIO_InitStruct.Mode      = GPIO_MODE_AF_PP;
        GPIO_InitStruct.Pull      = GPIO_PULLUP;
        GPIO_InitStruct.Speed     = GPIO_SPEED_FAST;
        GPIO_InitStruct.Alternate = USARTx_TX_AF;

        HAL_GPIO_Init(USARTx_TX_GPIO_PORT, &GPIO_InitStruct);
        
        /* UART RX GPIO pin configuration  */
        GPIO_InitStruct.Pin = USARTx_RX_PIN;
        GPIO_InitStruct.Alternate = USARTx_RX_AF;
        
        HAL_GPIO_Init(USARTx_RX_GPIO_PORT, &GPIO_InitStruct);
        
        HAL_NVIC_SetPriority(USART2_IRQn, 0, 1);
        HAL_NVIC_EnableIRQ(USART2_IRQn);
    }
}

/**
* @brief UART MSP De-Initialization
*        This function frees the hardware resources used in this example:
*          - Disable the Peripheral's clock
*          - Revert GPIO and NVIC configuration to their default state
* @param huart: UART handle pointer
* @retval None
*/
void HAL_UART_MspDeInit(UART_HandleTypeDef *huart)
{
    if (huart->Instance == USART2)
    {
        /*##-1- Reset peripherals ##################################################*/
        USARTx_FORCE_RESET();
        USARTx_RELEASE_RESET();

        /*##-2- Disable peripherals and GPIO Clocks #################################*/
        /* Configure UART Tx as alternate function  */
        HAL_GPIO_DeInit(USARTx_TX_GPIO_PORT, USARTx_TX_PIN);
        /* Configure UART Rx as alternate function  */
        HAL_GPIO_DeInit(USARTx_RX_GPIO_PORT, USARTx_RX_PIN);

        HAL_NVIC_DisableIRQ(USART2_IRQn);
    }
}

int hw_usart_init(void)
{
    struct drv_uart *uart;
    struct serial_configure config = RT_SERIAL_CONFIG_DEFAULT;

#ifdef RT_USING_UART2
    uart = &uart2;
    uart->UartHandle.Instance = USART2;

    serial2.ops    = &drv_uart_ops;
    serial2.config = config;

    /* register UART1 device */
    rt_hw_serial_register(&serial2, "uart2",
    RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_INT_RX,
    uart);
#endif /* RT_USING_UART1 */

    return 0;
}
INIT_BOARD_EXPORT(hw_usart_init);