/**************************************************************************//**
 * @file     main.c
 * @version  V3.00
 * @brief    M2A23 I2C Driver Sample Code
 *           This is a I2C slave mode demo and need to be tested with a master device.
 *
 * @copyright (C) 2024 Nuvoton Technology Corp. All rights reserved.
 *
 ******************************************************************************/
#include <stdio.h>
#include "NuMicro.h"

/*---------------------------------------------------------------------------------------------------------*/
/* Global variables                                                                                        */
/*---------------------------------------------------------------------------------------------------------*/
static uint32_t slave_buff_addr;
static uint8_t g_au8SlvData[256];
static uint8_t g_au8SlvRxData[3];
static volatile uint8_t g_u8SlvTRxAbortFlag = 0;
static volatile uint8_t g_u8TimeoutFlag = 0;

static volatile uint8_t g_u8DeviceAddr;
static uint8_t g_u8SlvDataLen;

typedef void (*I2C_FUNC)(uint32_t u32Status);

static I2C_FUNC s_I2C0HandlerFn = NULL;


void I2C0_IRQHandler(void)
{
    uint32_t u32Status;

    u32Status = I2C_GET_STATUS(I2C0);

    if (I2C_GET_TIMEOUT_FLAG(I2C0))
    {
        /* Clear I2C0 Timeout Flag */
        I2C_ClearTimeoutFlag(I2C0);
        g_u8TimeoutFlag = 1;
    }
    else
    {
        if (s_I2C0HandlerFn != NULL)
            s_I2C0HandlerFn(u32Status);
    }
}

/*---------------------------------------------------------------------------------------------------------*/
/*  I2C TRx Callback Function                                                                              */
/*---------------------------------------------------------------------------------------------------------*/
void I2C_SlaveTRx(uint32_t u32Status)
{
    uint8_t u8data;
    if (u32Status == 0x60)                      /* Own SLA+W has been receive; ACK has been return */
    {
        g_u8SlvDataLen = 0;
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI | I2C_CTL_AA);
    }
    else if (u32Status == 0x80)                 /* Previously address with own SLA address
                                                   Data has been received; ACK has been returned*/
    {
        u8data = (unsigned char) I2C_GET_DATA(I2C0);
        if(g_u8SlvDataLen < 2)
        {
            g_au8SlvRxData[g_u8SlvDataLen++] = u8data;
            slave_buff_addr = (g_au8SlvRxData[0] << 8) + g_au8SlvRxData[1];
        }
        else
        {
            g_au8SlvData[slave_buff_addr++] = u8data;
            if(slave_buff_addr == 256)
            {
                slave_buff_addr = 0;
            }
        }
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI | I2C_CTL_AA);
    }
    else if(u32Status == 0xA8)                  /* Own SLA+R has been receive; ACK has been return */
    {

        I2C_SET_DATA(I2C0, g_au8SlvData[slave_buff_addr]);
        slave_buff_addr++;
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI | I2C_CTL_AA);
    }
    else if(u32Status == 0xB8)                  /* Data byte in I2CDAT has been transmitted ACK has been received */
    {
        I2C_SET_DATA(I2C0, g_au8SlvData[slave_buff_addr]);
        slave_buff_addr++;
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI_AA);
    }
    else if (u32Status == 0xC0)                 /* Data byte or last data in I2CDAT has been transmitted
                                                   Not ACK has been received */
    {
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI | I2C_CTL_AA);
    }
    else if (u32Status == 0x88)                 /* Previously addressed with own SLA address; NOT ACK has
                                                   been returned */
    {
        g_u8SlvDataLen = 0;
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI | I2C_CTL_AA);
    }
    else if (u32Status == 0xA0)                 /* A STOP or repeated START has been received while still
                                                   addressed as Slave/Receiver*/
    {
        g_u8SlvDataLen = 0;
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI | I2C_CTL_AA);
    }
    else
    {
        printf("[SlaveTRx] Status [0x%x] Unexpected abort!!\n", u32Status);
        if(u32Status == 0x68)               /* Slave receive arbitration lost, clear SI */
        {
            I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI_AA);
        }
        else if(u32Status == 0xB0)          /* Address transmit arbitration lost, clear SI  */
        {
            I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI_AA);
        }
        else                                /* Slave bus error, stop I2C and clear SI */
        {
            I2C_SET_CONTROL_REG(I2C0, I2C_CTL_STO_SI);
            I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI);
        }
        g_u8SlvTRxAbortFlag = 1;
    }
    I2C_WAIT_SI_CLEAR(I2C0);
}

void SYS_Init(void)
{
    /*---------------------------------------------------------------------------------------------------------*/
    /* Init System Clock                                                                                       */
    /*---------------------------------------------------------------------------------------------------------*/

    /* Set core clock to 72MHz */
    CLK_SetCoreClock(72000000);

    /* Enable all GPIO clock */
    CLK->AHBCLK |= CLK_AHBCLK_GPIOACKEN_Msk | CLK_AHBCLK_GPIOBCKEN_Msk | CLK_AHBCLK_GPIOCCKEN_Msk |
                   CLK_AHBCLK_GPIODCKEN_Msk | CLK_AHBCLK_GPIOFCKEN_Msk ;

    /* Enable UART0 module clock */
    CLK_EnableModuleClock(UART0_MODULE);

    /* Select UART0 module clock source as HIRC and UART0 module clock divider as 1 */
    CLK_SetModuleClock(UART0_MODULE, CLK_CLKSEL2_UART0SEL_HIRC, CLK_CLKDIV0_UART0(1));

    /* Enable I2C0 clock */
    CLK_EnableModuleClock(I2C0_MODULE);

    /*---------------------------------------------------------------------------------------------------------*/
    /* Init I/O Multi-function                                                                                 */
    /*---------------------------------------------------------------------------------------------------------*/

    /* Set multi-function pins for UART0 RXD and TXD */
    SET_UART0_RXD_PB12();
    SET_UART0_TXD_PB13();

    /* Set I2C0 multi-function pins */
    SET_I2C0_SDA_PA4();
    SET_I2C0_SCL_PA5();

    /* I2C pin enable schmitt trigger */
    PA->SMTEN |= GPIO_SMTEN_SMTEN4_Msk | GPIO_SMTEN_SMTEN5_Msk;
}

void I2C0_Init(void)
{
    /* Open I2C0 and set clock to 100k */
    I2C_Open(I2C0, 100000);

    /* Get I2C0 Bus Clock */
    printf("I2C clock %d Hz\n", I2C_GetBusClockFreq(I2C0));

    /* Set I2C0 4 Slave Addresses */
    I2C_SetSlaveAddr(I2C0, 0, 0x15, I2C_GCMODE_DISABLE);   /* Slave Address : 0x15 */
    I2C_SetSlaveAddr(I2C0, 1, 0x35, I2C_GCMODE_DISABLE);   /* Slave Address : 0x35 */
    I2C_SetSlaveAddr(I2C0, 2, 0x55, I2C_GCMODE_DISABLE);   /* Slave Address : 0x55 */
    I2C_SetSlaveAddr(I2C0, 3, 0x75, I2C_GCMODE_DISABLE);   /* Slave Address : 0x75 */

    I2C_SetSlaveAddrMask(I2C0, 0, 0x01);
    I2C_SetSlaveAddrMask(I2C0, 1, 0x04);
    I2C_SetSlaveAddrMask(I2C0, 2, 0x01);
    I2C_SetSlaveAddrMask(I2C0, 3, 0x04);

    I2C_EnableInt(I2C0);
    NVIC_EnableIRQ(I2C0_IRQn);
}


int32_t main (void)
{
    uint32_t i, u32TimeOutCnt;

    /* Unlock protected registers */
    SYS_UnlockReg();

    /* Init System, IP clock and multi-function I/O */
    SYS_Init();

    /* Init UART to 115200-8n1 for print message */
    UART_Open(UART0, 115200);

    /*
        This sample code sets I2C bus clock to 100kHz. Then, Master accesses Slave with Byte Write
        and Byte Read operations, and check if the read data is equal to the programmed data.
    */

    printf("+----------------------------------------------------+\n");
    printf("| I2C Driver Sample Code(Slave) for access Slave     |\n");
    printf("| Needs to work with I2C_Master sample code          |\n");
    printf("| I2C Master (I2C0) <---> I2C Slave(I2C0)            |\n");
    printf("| !! This sample code requires two boards to test !! |\n");
    printf("+----------------------------------------------------+\n");

    printf("Configure I2C0 as a slave.\n");
    printf("The I/O connection for I2C0:\n");
    printf("I2C0_SDA(PA.4), I2C0_SCL(PA.5)\n");

    /* Init I2C0 */
    I2C0_Init();

    /* I2C enter no address SLV mode */
    I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI | I2C_CTL_AA);

    for (i = 0; i < 0x100; i++)
    {
        g_au8SlvData[i] = 0;
    }

    /* I2C function to Slave receive/transmit data */
    s_I2C0HandlerFn=I2C_SlaveTRx;

    printf("\n");
    printf("I2C Slave Mode is Running.\n");

    g_u8TimeoutFlag = 0;

    while(1)
    {
        /* Handle Slave timeout condition */
        if(g_u8TimeoutFlag)
        {
            printf(" SlaveTRx time out, any to reset IP\n");
            getchar();
            SYS->IPRST1 |= SYS_IPRST1_I2C0RST_Msk;
            SYS->IPRST1 = 0;
            I2C0_Init();
            g_u8TimeoutFlag = 0;
            g_u8SlvTRxAbortFlag = 1;
        }
        /* When I2C abort, clear SI to enter non-addressed SLV mode*/
        if(g_u8SlvTRxAbortFlag)
        {
            g_u8SlvTRxAbortFlag = 0;

            u32TimeOutCnt = I2C_TIMEOUT;
            while(I2C0->CTL0 & I2C_CTL0_SI_Msk)
                if(--u32TimeOutCnt == 0) break;

            printf("I2C Slave re-start. status[0x%x]\n", I2C0->STATUS0);
            I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI_AA);
        }
    }
}
