/*
 * File      : usart.c
 * This file is part of RT-Thread RTOS
 * COPYRIGHT (C) 2009, RT-Thread Development Team
 *
 * The license and distribution terms for this file may be
 * found in the file LICENSE in this distribution or at
 * http://www.rt-thread.org/license/LICENSE
 *
 * Change Logs:
 * Date           Author       Notes
 * 2009-01-05     Bernard      the first version
 * 2010-03-29     Bernard      remove interrupt Tx and DMA Rx mode
 */

#include "usart.h"
#include <serial.h>
#include <stm32f2xx.h>
#include <stm32f2xx_dma.h>

/*
 * Use UART1 as console output and finsh input
 * interrupt Rx and poll Tx (stream mode)
 *
 * Use UART2 with interrupt Rx and poll Tx
 * Use UART3 with DMA Tx and interrupt Rx -- DMA channel 2
 *
 * USART DMA setting on STM32
 * USART1 Tx --> DMA Channel 4
 * USART1 Rx --> DMA Channel 5
 * USART2 Tx --> DMA Channel 7
 * USART2 Rx --> DMA Channel 6
 * USART3 Tx --> DMA Channel 2
 * USART3 Rx --> DMA Channel 3
 */

#ifdef RT_USING_UART1
struct stm32_serial_int_rx uart1_int_rx;
struct stm32_serial_device uart1 =
{
	USART1,
	&uart1_int_rx,
	RT_NULL
};
struct rt_device uart1_device;
#endif

#ifdef RT_USING_UART2
struct stm32_serial_int_rx uart2_int_rx;
struct stm32_serial_device uart2 =
{
	USART2,
	&uart2_int_rx,
	RT_NULL
};
struct rt_device uart2_device;
#endif

#ifdef RT_USING_UART3
struct stm32_serial_int_rx uart3_int_rx;
struct stm32_serial_dma_tx uart3_dma_tx;
struct stm32_serial_device uart3 =
{
	USART3,
	&uart3_int_rx,
	&uart3_dma_tx
};
struct rt_device uart3_device;
#endif

#define USART1_DR_Base  0x40013804
#define USART2_DR_Base  0x40004404
#define USART3_DR_Base  0x40004804

/* USART1_REMAP = 0 */
#define UART1_GPIO_TX		GPIO_Pin_9
#define UART1_GPIO_RX		GPIO_Pin_10
#define UART1_GPIO			GPIOA
#define RCC_APBPeriph_UART1	RCC_APB2Periph_USART1
#define UART1_TX_DMA		DMA1_Channel4
#define UART1_RX_DMA		DMA1_Channel5

#if defined(STM32F10X_LD) || defined(STM32F10X_MD) || defined(STM32F10X_CL)
#define UART2_GPIO_TX	    GPIO_Pin_5
#define UART2_GPIO_RX	    GPIO_Pin_6
#define UART2_GPIO	    	GPIOD
#define RCC_APBPeriph_UART2	RCC_APB1Periph_USART2
#else /* for STM32F10X_HD */
/* USART2_REMAP = 0 */
#define UART2_GPIO_TX		GPIO_Pin_2
#define UART2_GPIO_RX		GPIO_Pin_3
#define UART2_GPIO			GPIOA
#define RCC_APBPeriph_UART2	RCC_APB1Periph_USART2
#define UART2_TX_DMA		DMA1_Channel7
#define UART2_RX_DMA		DMA1_Channel6
#endif

/* USART3_REMAP[1:0] = 00 */
#define UART3_GPIO_RX		GPIO_Pin_11
#define UART3_GPIO_TX		GPIO_Pin_10
#define UART3_GPIO			GPIOB
#define RCC_APBPeriph_UART3	RCC_APB1Periph_USART3
#define UART3_TX_DMA		DMA1_Channel2
#define UART3_RX_DMA		DMA1_Channel3

static void RCC_Configuration(void)
{
#ifdef RT_USING_UART1
	/* Enable USART1 and GPIOA clocks */
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
#endif
}

static void GPIO_Configuration(void)
{
	GPIO_InitTypeDef GPIO_InitStruct;

#ifdef RT_USING_UART1
	GPIO_InitStruct.GPIO_Mode=GPIO_Mode_AF;
	GPIO_InitStruct.GPIO_Speed=GPIO_Speed_50MHz;
	GPIO_InitStruct.GPIO_OType=GPIO_OType_PP;
	GPIO_InitStruct.GPIO_PuPd=GPIO_PuPd_UP;  

	GPIO_InitStruct.GPIO_Pin=GPIO_Pin_9|GPIO_Pin_10;
	GPIO_Init(GPIOA,&GPIO_InitStruct);

	GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_USART1);  
	GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_USART1);	
#endif
}

static void NVIC_Configuration(void)
{
	NVIC_InitTypeDef NVIC_InitStructure;

#ifdef RT_USING_UART1
	/* Enable the USART1 Interrupt */
	NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
	NVIC_Init(&NVIC_InitStructure);
#endif
}

/*
 * Init all related hardware in here
 * rt_hw_serial_init() will register all supported USART device
 */
void rt_hw_usart_init()
{
	USART_InitTypeDef USART_InitStructure;

	RCC_Configuration();

	GPIO_Configuration();

	NVIC_Configuration();

	/* uart init */
#ifdef RT_USING_UART1
	USART_DeInit(USART1);				
	USART_InitStructure.USART_BaudRate            = 115200;
	USART_InitStructure.USART_WordLength          = USART_WordLength_8b;
	USART_InitStructure.USART_StopBits            = USART_StopBits_1;
	USART_InitStructure.USART_Parity              = USART_Parity_No ;
	USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
	USART_InitStructure.USART_Mode                = USART_Mode_Rx | USART_Mode_Tx;

	USART_Init(USART1, &USART_InitStructure);

	/* register uart1 */
	rt_hw_serial_register(&uart1_device, "uart1",
		RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_INT_RX | RT_DEVICE_FLAG_STREAM,
		&uart1);

	/* enable interrupt */
	USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
	/* Enable USART1 */
	USART_Cmd(USART1, ENABLE);
	USART_ClearFlag(USART1,USART_FLAG_TXE);
#endif
}

void USART1_IRQHandler()
{
    /* enter interrupt */
    rt_interrupt_enter();

    rt_hw_serial_isr(&uart1_device);

    /* leave interrupt */
    rt_interrupt_leave();
}