doubao_chat/apps/common/iic/software_iic.c

#include "system/init.h"
#include "device/device.h"
#include "device/iic.h"
#include "device/gpio.h"

#include "asm/cpu.h"
#include "asm/gpio.h"

#define IIC_DELAY_COUNT  iic->sw_iic_delay

#define INIT_IIC(iic) \
    do { \
        __gpio_direction_output(iic->dat_pin, 1); \
        __gpio_set_pull_down(iic->dat_pin, 0); \
        __gpio_set_pull_up(iic->dat_pin, 1); \
        __gpio_set_die(iic->dat_pin, 1); \
        __gpio_direction_output(iic->clk_pin, 1); \
        __gpio_set_pull_down(iic->clk_pin, 0); \
        __gpio_set_pull_up(iic->clk_pin, 1); \
        __gpio_set_die(iic->clk_pin, 1); \
    }while(0)

#define SCCB_SID_H(iic)    \
		do { \
            __gpio_set_pull_up(iic->dat_pin, 1); \
            __gpio_direction_output(iic->dat_pin, 1); \
		}while(0)

#define SCCB_SID_L(iic)    \
		do { \
            __gpio_set_pull_up(iic->dat_pin, 1); \
            __gpio_direction_output(iic->dat_pin, 0); \
		}while(0)

#define SCCB_SIC_H(iic)    \
		do { \
            __gpio_set_pull_up(iic->clk_pin, 1); \
            __gpio_direction_output(iic->clk_pin, 1); \
		}while(0)

#define SCCB_SIC_L(iic)    \
		do { \
            __gpio_set_pull_up(iic->clk_pin, 1); \
            __gpio_direction_output(iic->clk_pin, 0); \
		}while(0)

#define SCCB_SID_IN(iic) \
	do { \
        __gpio_direction_input(iic->dat_pin); \
	}while(0)

#define SCCB_SID_OUT(iic) \
	do { \
        __gpio_direction_output(iic->dat_pin, 0); \
	}while(0)

#define SCCB_SID_STATE(iic) \
    __gpio_read(iic->dat_pin)


static void iic_start(const struct software_iic *iic)
{
    INIT_IIC(iic);

    SCCB_SID_H(iic);
    SCCB_SIC_H(iic);
    delay(IIC_DELAY_COUNT * 2);

    SCCB_SID_L(iic);
    delay(IIC_DELAY_COUNT);

    SCCB_SIC_L(iic);
    delay(IIC_DELAY_COUNT);
}

static void iic_stop(const struct software_iic *iic)
{
    SCCB_SIC_L(iic);
    delay(IIC_DELAY_COUNT);

    SCCB_SID_L(iic);
    delay(IIC_DELAY_COUNT);

    SCCB_SIC_H(iic);
    delay(IIC_DELAY_COUNT * 2);

    SCCB_SID_H(iic);
    delay(IIC_DELAY_COUNT);
}

static u8 iic_wait_ack(const struct software_iic *iic)
{
    int ucErrTime = 0;

    SCCB_SID_IN(iic);
    delay(IIC_DELAY_COUNT);

    SCCB_SIC_H(iic);
    delay(IIC_DELAY_COUNT);

    while (SCCB_SID_STATE(iic)) {
        if (++ucErrTime > 250) {
            iic_stop(iic);
            return 1;
        }
    }

    delay(IIC_DELAY_COUNT);

    SCCB_SIC_L(iic);
    delay(IIC_DELAY_COUNT);

    return 0;
}

static void iic_ack(const struct software_iic *iic)
{
    /* SCCB_SIC_L(iic); */
    /* delay(IIC_DELAY_COUNT); */

    SCCB_SID_L(iic);
    delay(IIC_DELAY_COUNT);

    SCCB_SIC_H(iic);
    delay(IIC_DELAY_COUNT * 2);

    SCCB_SIC_L(iic);
    delay(IIC_DELAY_COUNT);
}

static void iic_noack(const struct software_iic *iic)
{
    /* SCCB_SIC_L(iic); */
    /* delay(IIC_DELAY_COUNT); */

    SCCB_SID_H(iic);
    delay(IIC_DELAY_COUNT);

    SCCB_SIC_H(iic);
    delay(IIC_DELAY_COUNT * 2);

    SCCB_SIC_L(iic);
    delay(IIC_DELAY_COUNT);
}

static u8 iic_tx(const struct software_iic *iic, u8 m_iic)
{
    unsigned char j, tem;

    SCCB_SIC_L(iic);

    for (j = 0; j < 8; j++) {
        if ((m_iic << j) & 0x80) {
            SCCB_SID_H(iic);
        } else {
            SCCB_SID_L(iic);
        }
        delay(IIC_DELAY_COUNT);

        SCCB_SIC_H(iic);
        delay(IIC_DELAY_COUNT * 2);

        SCCB_SIC_L(iic);
        delay(IIC_DELAY_COUNT);
    }

    tem = iic_wait_ack(iic);

    SCCB_SID_OUT(iic);

    return tem;
}

static u8 iic_rx(const struct software_iic *iic)
{
    u8 read = 0, j;

    SCCB_SID_IN(iic);

    for (j = 8; j > 0; j--) {
        delay(IIC_DELAY_COUNT);

        SCCB_SIC_H(iic);
        delay(IIC_DELAY_COUNT);

        read = read << 1;
        if (SCCB_SID_STATE(iic)) {
            read = read + 1;
        }
        delay(IIC_DELAY_COUNT);

        SCCB_SIC_L(iic);
        delay(IIC_DELAY_COUNT);
    }

    return read;
}

static int iic_read(struct iic_device *iic, void *buf, int len)
{
    return 0;
}

static int iic_write(struct iic_device *iic, void *buf, int len)
{
    int i;
    u8 *p = (u8 *)buf;

    iic_start(iic->hw);

    for (i = 0; i < len; i++) {
        iic_tx(iic->hw, p[i]);

        if (iic->nrate > 1 && ((i + 1) % iic->nrate) == 0) {
            iic_stop(iic->hw);
            if (i + 1 == len) {
                return len;
            }
            delay(100);
            iic_start(iic->hw);
        }
    }

    iic_stop(iic->hw);
    return len;
}

static int iic_ioctl(struct iic_device *iic, int cmd, int arg)
{
    int ret = 0;
    struct software_iic *hw = (struct software_iic *)iic->hw;
    u8 tmp = 0;

    switch (cmd) {
    case IOCTL_SET_SPEED:
        break;
    case IIC_IOCTL_TX_START_BIT:
        iic_start(iic->hw);
        break;
    case IIC_IOCTL_TX_STOP_BIT:
        iic_stop(iic->hw);
        break;
    case IIC_IOCTL_TX_WITH_START_BIT:
        iic_start(iic->hw);
        ret = iic_tx(iic->hw, arg);
        break;
    case IIC_IOCTL_TX:
        ret = iic_tx(iic->hw, arg);
        break;
    case IIC_IOCTL_TX_WITH_STOP_BIT:
        ret = iic_tx(iic->hw, arg);
        iic_stop(iic->hw);
        break;
    case IIC_IOCTL_RX:
        tmp = iic_rx(iic->hw);
        if (arg) {
            *((u8 *)arg) = tmp;
        }
        iic_ack(iic->hw);
        break;
    case IIC_IOCTL_RX_WITH_STOP_BIT:
        tmp = iic_rx(iic->hw);
        if (arg) {
            *((u8 *)arg) = tmp;
        }
        iic_noack(iic->hw);
        iic_stop(iic->hw);
        break;
    case IIC_IOCTL_RX_WITH_NOACK:
        tmp = iic_rx(iic->hw);
        if (arg) {
            *((u8 *)arg) = tmp;
        }
        iic_noack(iic->hw);
        break;
    case IIC_IOCTL_RX_WITH_ACK:
        tmp = iic_rx(iic->hw);
        if (arg) {
            *((u8 *)arg) = tmp;
        }
        iic_ack(iic->hw);
        break;
    case IIC_IOCTL_SET_NORMAT_RATE:
        iic->nrate = arg + 1;
        break;
    case IIC_IOCTL_START:
        gpio_port_lock(GPIO2PORT(hw->dat_pin));
        if (GPIO2PORT(hw->dat_pin) != GPIO2PORT(hw->clk_pin)) {
            gpio_port_lock(GPIO2PORT(hw->clk_pin));
        }
        break;
    case IIC_IOCTL_STOP:
        gpio_port_unlock(GPIO2PORT(hw->dat_pin));
        if (GPIO2PORT(hw->dat_pin) != GPIO2PORT(hw->clk_pin)) {
            gpio_port_unlock(GPIO2PORT(hw->clk_pin));
        }
        break;
    default:
        return -EINVAL;
    }

    if (ret) {
        iic_stop(iic->hw);
    }
    return ret;
}

static int iic_close(struct iic_device *iic)
{
    struct software_iic *hw = (struct software_iic *)iic->hw;

    gpio_direction_input(hw->clk_pin);
    gpio_set_pull_down(hw->clk_pin, 0);
    gpio_set_pull_up(hw->clk_pin, 0);
    gpio_set_die(hw->clk_pin, 0);

    gpio_direction_input(hw->dat_pin);
    gpio_set_pull_down(hw->dat_pin, 0);
    gpio_set_pull_up(hw->dat_pin, 0);
    gpio_set_die(hw->dat_pin, 0);

    return 0;
}

REGISTER_IIC_DEVICE(sw_iic_ops) = {
    .type   = IIC_TYPE_SW,
    .read   = iic_read,
    .write  = iic_write,
    .ioctl  = iic_ioctl,
    .close  = iic_close,
};