#include "board.h"

//static struct rt_event event_i2c1;
//static uint8_t SlvAddrRWE;
//static uint8_t *PtrBuf;
//static int16_t BufLen;
//static uint32_t PinSCL;
//static uint32_t PinSDA;

#define I2C1_CR_CFG ( \
    (1<<6) |     /* ens, I2C module 0:off; 1:on; */ \
    (1<<0)       /* hlm, 0:advance filter(TM must>9); 1:simple filter; */ \
)

#define I2C1_CR_START   (1u<<5)
#define I2C1_CR_STOP    (1u<<4)

#define I2C1_CR_SI      (1u<<3)
#define I2C1_CR_HOLD    (1u<<3)
#define I2C1_CR_NEXT    (0u<<3)

#define I2C1_CR_ACK     (1u<<2)
#define I2C1_CR_NACK    (0u<<2)

typedef enum i2c_stat_code{
    I2C_TX_START            = 0x08u,
    I2C_TX_RESTART          = 0x10u,
    I2C_TX_WADDR_ACK        = 0x18u,
    I2C_TX_WADDR_NACK       = 0x20u,
    I2C_TX_WDATA_ACK        = 0x28u,
    I2C_TX_WDATA_NACK       = 0x30u,
    I2C_TX_CLOCK_FAIL       = 0x38u,

    I2C_TX_RADDR_ACK        = 0x40u,
    I2C_TX_RADDR_NACK       = 0x48u,
    I2C_RX_RDATA_ACK        = 0x50u,
    I2C_RX_RDATA_NACK       = 0x58u,

    I2C_RX_WADDR_ACK        = 0x60u,
    I2C_RX_WADDR_ACK_M2S    = 0x68u,
    I2C_RX_WDATA_ACK        = 0x80u,
    I2C_RX_WDATA_NACK       = 0x88u,
    I2C_RX_WEND             = 0xA0u,

    I2C_RX_RADDR_ACK        = 0xA8u,
    I2C_RX_RADDR_ACK_M2S    = 0xB0u,
    I2C_TX_RDATA_ACK        = 0xB8u,
    I2C_TX_RDATA_NACK       = 0xC0u,
} i2c_stat_code_t;

// PD10: 1:power on; 0:power off;
// PA15: write protect for EEPROM, 1: write forbid; 0:allow write;
// PF07: I2C1_SDA
// PF06: I2C1_SCL
void eeprom_init(void)    // for EEPROM(M24M01 128KByts) chip
{
//    GpioSetPins(GpioPortD, GpioBitMsk10);  // power on
    GpioClrPins(GpioPortD, GpioBitMsk10);  // power off
    GpioInit(PD10_AF0, GPIO_DIG_OUT_WEAK_PUSH_NONEUP_NONEDOWN);
    
    // keep I2C1_WP same level as PIN_VCC_I2C for saving power
//    GpioSetPins(GpioPortA, GpioBitMsk15);  // write protect on
    GpioClrPins(GpioPortA, GpioBitMsk15);  // write protect off
    GpioInit(PA15_AF0, GPIO_DIG_OUT_WEAK_PUSH_NONEUP_NONEDOWN);

    PeriClk_MutEnable(PeriClk_I2c1);
    MutResetPeri(ResetI2c1);        // not asynchronous reset, must be effective after enable clock

    // Fscl = Fpclk/8/(TM+1)
#if defined(SYSCLK_4M_MODE)
    M0P_I2C1->TM = 0x1;     // Fscl = 250KHz
#elif defined(SYSCLK_8M_MODE)
    M0P_I2C1->TM = 0x1;     // Fscl = 500KHz
#elif defined(SYSCLK_16M_MODE)
    M0P_I2C1->TM = 0x3;     // Fscl = 500KHz
#endif

    M0P_I2C1->TMRUN = 0x1;  // 0:Baud rate off; 1:Baud rate on;
    M0P_I2C1->CR = I2C1_CR_CFG | I2C1_CR_HOLD;

    PeriClk_MutDisable(PeriClk_I2c1);

    // EEPROM
    GpioInit(PF06_I2C1_SCL, GPIO_DIG_OUT_WEAK_OPEN_NONEUP_NONEDOWN);   // set pin to output open
    GpioInit(PF07_I2C1_SDA, GPIO_DIG_OUT_WEAK_OPEN_NONEUP_NONEDOWN);   // set pin to output open

//    // enable interrupt at NVIC side
//    IRQMutEnable(I2C1_IRQn, IRQnPriority3);
}

void i2c1_rescue(void)
{
    int16_t i;

    GpioSetPins(GpioPortF, GpioBitMsk6);  // I2C1_SCL
    GpioSetPins(GpioPortF, GpioBitMsk7);  // I2C1_SDA

    GpioInit(PF06_AF0, GPIO_DIG_OUT_WEAK_OPEN_NONEUP_NONEDOWN);   // set pin to output open
    GpioInit(PF07_AF0, GPIO_DIG_OUT_WEAK_OPEN_NONEUP_NONEDOWN);   // set pin to output open

    i = 10;
    while(i--){
        GpioClrPins(GpioPortF, GpioBitMsk6);  // I2C1_SCL
        GpioSetPins(GpioPortF, GpioBitMsk6);  // I2C1_SCL
    }

    GpioInit(PF06_I2C1_SCL, GPIO_DIG_OUT_WEAK_OPEN_NONEUP_NONEDOWN);   // set pin to output open
    GpioInit(PF07_I2C1_SDA, GPIO_DIG_OUT_WEAK_OPEN_NONEUP_NONEDOWN);   // set pin to output open
}

// Len is for data only, address byte is not included
uint8_t I2C1_RdWrPacket(uint8_t AddrRWE, uint8_t *Buf, uint16_t Len)
{
    uint8_t i2c_next;
    uint8_t i2c_error;

    PeriClk_MutEnable(PeriClk_I2c1);

    M0P_I2C1->CR = I2C1_CR_CFG | I2C1_CR_START | I2C1_CR_NEXT;
    i2c_next = 0x1u;

    while(i2c_next){
        while((~M0P_I2C1->CR) & I2C1_CR_SI){
            // wait until SI=1
        }

        switch(M0P_I2C1->STAT){
            case(I2C_TX_START):
            case(I2C_TX_RESTART):
                M0P_I2C1->DATA = AddrRWE;
                M0P_I2C1->CR = I2C1_CR_CFG | I2C1_CR_NEXT;
                break;

            case(I2C_TX_WADDR_ACK):
            case(I2C_TX_WDATA_ACK):
                if (Len<=0){
                    M0P_I2C1->CR = I2C1_CR_CFG | I2C1_CR_STOP | I2C1_CR_NEXT;
                    i2c_error = 0x0u;
                    i2c_next = 0x0u;
                } else {
                    Len--;
                    M0P_I2C1->DATA = *(Buf++);
                    M0P_I2C1->CR = I2C1_CR_CFG | I2C1_CR_NEXT;
                }
                break;

            case(I2C_RX_RDATA_ACK):
            case(I2C_RX_RDATA_NACK):
                *(Buf++) = M0P_I2C1->DATA;
            case(I2C_TX_RADDR_ACK):
                if (Len<=0){
                    M0P_I2C1->CR = I2C1_CR_CFG | I2C1_CR_STOP | I2C1_CR_NEXT;
                    i2c_error = 0x0u;
                    i2c_next = 0x0u;
                } else {
                    if (Len==1){
                        M0P_I2C1->CR = I2C1_CR_CFG | I2C1_CR_NACK | I2C1_CR_NEXT;
                    } else {
                        M0P_I2C1->CR = I2C1_CR_CFG | I2C1_CR_ACK  | I2C1_CR_NEXT;
                    }
                    Len--;
                }
                break;

            default:
                M0P_I2C1->CR = I2C1_CR_CFG | I2C1_CR_STOP | I2C1_CR_NEXT;
                i2c_error = 0x1u;
                i2c_next = 0x0u;
        }
    }

    PeriClk_MutDisable(PeriClk_I2c1);
    if (i2c_error){
        return(0x1u);   // fail
    } else {
        return(0x0u);   // ok
    }
}

// NOTE: Page size is 256Bytes, so any write must not cross page boundary
// size of Buf >= DLen+3 (Must)
// Buf[0] is address A16
// Buf[1] is address A15-A8
// Buf[2] is address A7-A0
// Buf[3]~Buf[DLen+2] is WR data
// DLen>=1, at least 1 WR data(be sure (A[7:0] + DLen) <=256)
uint8_t EEPROM_WrPacket(uint8_t *Buf, uint16_t DLen)
{
    uint8_t ret;
    uint8_t AddrRWE;

    GpioSetPins(GpioPortA, GpioBitMsk15);  // write protect on
    GpioSetPins(GpioPortD, GpioBitMsk10);  // power on
    AddrRWE = ((Buf[0]&0x01u)<<1) | 0xA0u;

    GpioClrPins(GpioPortA, GpioBitMsk15);  // write protect off
    ret = I2C1_RdWrPacket(AddrRWE, Buf+1, DLen+2);
    GpioSetPins(GpioPortA, GpioBitMsk15);  // write protect on

    //us_delay(5000); // tW = 5ms
		rt_thread_mdelay(5);
    // keep I2C1_WP same level as PIN_VCC_I2C for saving power
    GpioClrPins(GpioPortD, GpioBitMsk10);  // power off
    GpioClrPins(GpioPortA, GpioBitMsk15);  // write protect off
    return(ret);
}

// size of Buf >= DLen+3 (Must)
// Buf[0] is address A16
// Buf[1] is address A15-A8
// Buf[2] is address A7-A0
// Buf[3]~Buf[DLen+2] is RD data
// DLen>=1, at least 1 WR data
uint8_t EEPROM_RdPacket(uint8_t *Buf, uint16_t DLen)
{
    uint8_t ret;
    uint8_t AddrRWE;

    GpioSetPins(GpioPortA, GpioBitMsk15);  // write protect on
    GpioSetPins(GpioPortD, GpioBitMsk10);  // power on
    AddrRWE = ((Buf[0]&0x01u)<<1) | 0xA0u;
    ret = I2C1_RdWrPacket(AddrRWE, Buf+1, 2);

    if (ret){
        return(ret);
    }

    AddrRWE |= 0x01u;
    ret = I2C1_RdWrPacket(AddrRWE,  Buf+3, DLen);

    // keep I2C1_WP same level as PIN_VCC_I2C for saving power
    GpioClrPins(GpioPortD, GpioBitMsk10);  // power off
    GpioClrPins(GpioPortA, GpioBitMsk15);  // write protect off
    return(ret);
}