/*
 * Copyright (C) 2017 C-SKY Microsystems Co., Ltd. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/******************************************************************************
 * @file     dw_usart.c
 * @brief    CSI Source File for usart Driver
 * @version  V1.0
 * @date     02. June 2017
 ******************************************************************************/
#include <stdbool.h>
#include "csi_core.h"
#include "drv_usart.h"
#include "dw_usart.h"
#include "soc.h"

#define ERR_USART(errno) (CSI_DRV_ERRNO_USART_BASE | errno)

/*
 * setting config may be accessed when the USART is not
 * busy(USR[0]=0) and the DLAB bit(LCR[7]) is set.
 */

#define WAIT_USART_IDLE(addr)\
    do {                       \
        int32_t timecount = 0;  \
        while ((addr->USR & USR_UART_BUSY) && (timecount < UART_BUSY_TIMEOUT)) {\
            timecount++;\
        }\
        if (timecount >= UART_BUSY_TIMEOUT) {\
            return ERR_USART(EDRV_TIMEOUT);\
        }                                   \
    } while(0)

#define USART_NULL_PARAM_CHK(para)                   \
    do {                                        \
        if (para == NULL) {                     \
            return ERR_USART(EDRV_PARAMETER);   \
        }                                       \
    } while (0)

typedef struct {
    uint32_t base;
} dw_usart_priv_t;

extern int32_t target_usart_init(pin_t tx, pin_t rx, uint32_t *base, uint32_t *irq);
extern int32_t target_usart_flowctrl_init(pin_t tx_flow, pin_t rx_flow, uint32_t flag);

static dw_usart_priv_t usart_instance[CONFIG_USART_NUM];

static const usart_capabilities_t usart_capabilities = {
    .asynchronous = 0,          /* supports USART (Asynchronous) mode */
    .synchronous_master = 0,    /* supports Synchronous Master mode */
    .synchronous_slave = 0,     /* supports Synchronous Slave mode */
    .single_wire = 0,           /* supports USART Single-wire mode */
    .event_tx_complete = 0,     /* Transmit completed event */
    .event_rx_timeout = 0,      /* Signal receive character timeout event */
};

/**
  \brief       set the baut drate of usart.
  \param[in]   addr  usart base to operate.
  \param[in]   baudrate baud rate
  \param[in]   apbfreq the frequency of the apb.
  \return      error code
*/
int32_t csi_usart_config_baudrate(usart_handle_t handle, uint32_t baudrate, uint32_t apbfreq)
{
    USART_NULL_PARAM_CHK(handle);
    dw_usart_priv_t *usart_priv = handle;
    dw_usart_reg_t *addr = (dw_usart_reg_t *)(usart_priv->base);


#ifdef CONFIG_CHIP_HOBBIT1_2
    uint8_t data[16];
    csi_usart_receive_query(handle, data, 16);
#endif

    WAIT_USART_IDLE(addr);

    /* baudrate=(seriak clock freq)/(16*divisor); algorithm :rounding*/
    uint32_t divisor = ((apbfreq  * 10) / baudrate) >> 4;

    if ((divisor % 10) >= 5) {
        divisor = (divisor / 10) + 1;
    } else {
        divisor = divisor / 10;
    }

    addr->LCR |= LCR_SET_DLAB;
    /* DLL and DLH is lower 8-bits and higher 8-bits of divisor.*/
    addr->DLL = divisor & 0xff;
    addr->DLH = (divisor >> 8) & 0xff;
    /*
     * The DLAB must be cleared after the baudrate is setted
     * to access other registers.
     */
    addr->LCR &= (~LCR_SET_DLAB);

    return 0;
}

/**
  \brief       config usart mode.
  \param[in]   handle  usart handle to operate.
  \param[in]   mode    \ref usart_mode_e
  \return      error code
*/
int32_t csi_usart_config_mode(usart_handle_t handle, usart_mode_e mode)
{
    if (mode == USART_MODE_ASYNCHRONOUS) {
        return 0;
    }

    return ERR_USART(EDRV_USART_MODE);
}

/**
  \brief       config usart parity.
  \param[in]   handle  usart handle to operate.
  \param[in]   parity    \ref usart_parity_e
  \return      error code
*/
int32_t csi_usart_config_parity(usart_handle_t handle, usart_parity_e parity)
{
    USART_NULL_PARAM_CHK(handle);
    dw_usart_priv_t *usart_priv = handle;
    dw_usart_reg_t *addr = (dw_usart_reg_t *)(usart_priv->base);

    WAIT_USART_IDLE(addr);

    switch (parity) {
        case USART_PARITY_NONE:
            /*CLear the PEN bit(LCR[3]) to disable parity.*/
            addr->LCR &= (~LCR_PARITY_ENABLE);
            break;

        case USART_PARITY_ODD:
            /* Set PEN and clear EPS(LCR[4]) to set the ODD parity. */
            addr->LCR |= LCR_PARITY_ENABLE;
            addr->LCR &= LCR_PARITY_ODD;
            break;

        case USART_PARITY_EVEN:
            /* Set PEN and EPS(LCR[4]) to set the EVEN parity.*/
            addr->LCR |= LCR_PARITY_ENABLE;
            addr->LCR |= LCR_PARITY_EVEN;
            break;

        default:
            return ERR_USART(EDRV_USART_PARITY);
    }

    return 0;
}

/**
  \brief       config usart stop bit number.
  \param[in]   handle  usart handle to operate.
  \param[in]   stopbits  \ref usart_stop_bits_e
  \return      error code
*/
int32_t dw_usart_config_stopbits(usart_handle_t handle, usart_stop_bits_e stopbit)
{
    USART_NULL_PARAM_CHK(handle);
    dw_usart_priv_t *usart_priv = handle;
    dw_usart_reg_t *addr = (dw_usart_reg_t *)(usart_priv->base);

    WAIT_USART_IDLE(addr);

    switch (stopbit) {
        case USART_STOP_BITS_1:
            /* Clear the STOP bit to set 1 stop bit*/
            addr->LCR &= LCR_STOP_BIT1;
            break;

        case USART_STOP_BITS_2:
            /*
            * If the STOP bit is set "1",we'd gotten 1.5 stop
            * bits when DLS(LCR[1:0]) is zero, else 2 stop bits.
            */
            addr->LCR |= LCR_STOP_BIT2;
            break;

        default:
            return ERR_USART(EDRV_USART_STOP_BITS);
    }

    return 0;
}

/**
  \brief       config usart data length.
  \param[in]   handle  usart handle to operate.
  \param[in]   databits      \ref usart_data_bits_e
  \return      error code
*/
int32_t csi_usart_config_databits(usart_handle_t handle, usart_data_bits_e databits)
{
    USART_NULL_PARAM_CHK(handle);
    dw_usart_priv_t *usart_priv = handle;
    dw_usart_reg_t *addr = (dw_usart_reg_t *)(usart_priv->base);

#ifdef CONFIG_CHIP_HOBBIT1_2
    uint8_t data[16];
    csi_usart_receive_query(handle, data, 16);
#endif

    WAIT_USART_IDLE(addr);
    /* The word size decides by the DLS bits(LCR[1:0]), and the
     * corresponding relationship between them is:
     *   DLS   word size
     *       00 -- 5 bits
     *       01 -- 6 bits
     *       10 -- 7 bits
     *       11 -- 8 bits
     */

    switch (databits) {
        case USART_DATA_BITS_5:
            addr->LCR &= LCR_WORD_SIZE_5;
            break;

        case USART_DATA_BITS_6:
            addr->LCR &= 0xfd;
            addr->LCR |= LCR_WORD_SIZE_6;
            break;

        case USART_DATA_BITS_7:
            addr->LCR &= 0xfe;
            addr->LCR |= LCR_WORD_SIZE_7;
            break;

        case USART_DATA_BITS_8:
            addr->LCR |= LCR_WORD_SIZE_8;
            break;

        default:
            return ERR_USART(EDRV_USART_DATA_BITS);
    }

    return 0;
}

/**
  \brief       get character in query mode.
  \param[in]   handle  usart handle to operate.
  \param[in]   the pointer to the received character if return 0.
  \return      error code
*/
int32_t csi_usart_getchar(usart_handle_t handle, uint8_t *ch)
{
    dw_usart_priv_t *usart_priv = handle;
    dw_usart_reg_t *addr = (dw_usart_reg_t *)(usart_priv->base);

    while (!(addr->LSR & LSR_DATA_READY));

    *ch = addr->RBR;

    return 0;
}

/**
  \brief       transmit character in query mode.
  \param[in]   handle  usart handle to operate.
  \param[in]   ch  the input character
  \return      error code
*/
int32_t csi_usart_putchar(usart_handle_t handle, uint8_t ch)
{
    dw_usart_priv_t *usart_priv = handle;
    dw_usart_reg_t *addr = (dw_usart_reg_t *)(usart_priv->base);

    while ((!(addr->LSR & DW_LSR_TRANS_EMPTY)));

    addr->THR = ch;

    return 0;
}

/**
  \brief       the interrupt service function.
  \param[in]   index of usart instance.
*/
void dw_usart_irqhandler(int32_t idx)
{
    (void)idx;
}

/**
  \brief       Get driver capabilities.
  \param[in]   handle  usart handle to operate.
  \return      \ref usart_capabilities_t
*/
usart_capabilities_t csi_usart_get_capabilities(usart_handle_t handle)
{
    return usart_capabilities;
}

/**
  \brief       Initialize USART Interface. 1. Initializes the resources needed for the USART interface 2.registers event callback function
  \param[in]   usart pin of tx
  \param[in]   usart pin of rx
  \param[in]   cb_event  Pointer to \ref usart_event_cb_t
  \return      return usart handle if success
*/
usart_handle_t csi_usart_initialize(pin_t tx, pin_t rx, usart_event_cb_t cb_event, void *cb_arg)
{
    uint32_t base = 0u;
    uint32_t irq = 0u;
    int32_t idx = target_usart_init(tx, rx, &base, &irq);

    if (idx < 0 || idx >= CONFIG_USART_NUM) {
        return NULL;
    }

    dw_usart_priv_t *usart_priv = &usart_instance[idx];
    usart_priv->base = base;

    dw_usart_reg_t *addr = (dw_usart_reg_t *)(usart_priv->base);
    /* FIFO enable */
    addr->FCR = DW_FCR_FIFOE | DW_FCR_RT_FIFO_HALF;

    return usart_priv;
}

/**
  \brief       De-initialize UART Interface. stops operation and releases the software resources used by the interface
  \param[in]   handle  usart handle to operate.
  \return      error code
*/
int32_t csi_usart_uninitialize(usart_handle_t handle)
{
    USART_NULL_PARAM_CHK(handle);
    return 0;
}

/**
  \brief       config usart mode.
  \param[in]   handle  usart handle to operate.
  \param[in]   sysclk    configured system clock.
  \param[in]   baud      baud rate
  \param[in]   mode      \ref usart_mode_e
  \param[in]   parity    \ref usart_parity_e
  \param[in]   stopbits  \ref usart_stop_bits_e
  \param[in]   bits      \ref usart_data_bits_e
  \return      error code
*/
int32_t csi_usart_config(usart_handle_t handle,
                         uint32_t sysclk,
                         uint32_t baud,
                         usart_mode_e mode,
                         usart_parity_e parity,
                         usart_stop_bits_e stopbits,
                         usart_data_bits_e bits)
{
    int32_t ret;

    /* control the data_bit of the usart*/
    ret = csi_usart_config_baudrate(handle, baud, sysclk);

    if (ret < 0) {
        return ret;
    }

    /* control mode of the usart*/
    ret = csi_usart_config_mode(handle, mode);

    if (ret < 0) {
        return ret;
    }

    /* control the parity of the usart*/
    ret = csi_usart_config_parity(handle, parity);

    if (ret < 0) {
        return ret;
    }

    /* control the stopbit of the usart*/
    ret = dw_usart_config_stopbits(handle, stopbits);

    if (ret < 0) {
        return ret;
    }

    ret = csi_usart_config_databits(handle, bits);

    if (ret < 0) {
        return ret;
    }

    return 0;
}

/**
  \brief       config usart default tx value. used in syn mode
  \param[in]   handle  usart handle to operate.
  \param[in]   value  default tx value
  \return      error code
*/
int32_t csi_usart_set_default_tx_value(usart_handle_t handle, uint32_t value)
{
    USART_NULL_PARAM_CHK(handle);
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       Start sending data to UART transmitter,(received data is ignored).
               The function is non-blocking,UART_EVENT_TRANSFER_COMPLETE is signaled when transfer completes.
               csi_usart_get_status can indicates if transmission is still in progress or pending
  \param[in]   handle  usart handle to operate.
  \param[in]   data  Pointer to buffer with data to send to UART transmitter. data_type is : uint8_t for 1..8 data bits, uint16_t for 9..16 data bits,uint32_t for 17..32 data bits,
  \param[in]   num   Number of data items to send
  \return      error code
*/
int32_t csi_usart_send(usart_handle_t handle, const void *data, uint32_t num)
{
    USART_NULL_PARAM_CHK(handle);
    USART_NULL_PARAM_CHK(data);

    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       Abort Send data to UART transmitter
  \param[in]   handle  usart handle to operate.
  \return      error code
*/
int32_t csi_usart_abort_send(usart_handle_t handle)
{
    USART_NULL_PARAM_CHK(handle);
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       Start receiving data from UART receiver.transmits the default value as specified by csi_usart_set_default_tx_value
  \param[in]   handle  usart handle to operate.
  \param[out]  data  Pointer to buffer for data to receive from UART receiver
  \param[in]   num   Number of data items to receive
  \return      error code
*/
int32_t csi_usart_receive(usart_handle_t handle, void *data, uint32_t num)
{
    return ERR_USART(EDRV_UNSUPPORTED);

}

/**
  \brief       query data from UART receiver FIFO.
  \param[in]   handle  usart handle to operate.
  \param[out]  data  Pointer to buffer for data to receive from UART receiver
  \param[in]   num   Number of data items to receive
  \return      receive fifo data num
*/
int32_t csi_usart_receive_query(usart_handle_t handle, void *data, uint32_t num)
{
    return ERR_USART(EDRV_UNSUPPORTED);

}

/**
  \brief       Abort Receive data from UART receiver
  \param[in]   handle  usart handle to operate.
  \return      error code
*/
int32_t csi_usart_abort_receive(usart_handle_t handle)
{
    USART_NULL_PARAM_CHK(handle);
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       Start sending/receiving data to/from UART transmitter/receiver.
  \param[in]   handle  usart handle to operate.
  \param[in]   data_out  Pointer to buffer with data to send to USART transmitter
  \param[out]  data_in   Pointer to buffer for data to receive from USART receiver
  \param[in]   num       Number of data items to transfer
  \return      error code
*/
int32_t csi_usart_transfer(usart_handle_t handle, const void *data_out, void *data_in, uint32_t num)
{
    USART_NULL_PARAM_CHK(handle);
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       abort sending/receiving data to/from USART transmitter/receiver.
  \param[in]   handle  usart handle to operate.
  \return      error code
*/
int32_t csi_usart_abort_transfer(usart_handle_t handle)
{
    USART_NULL_PARAM_CHK(handle);
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       Get USART status.
  \param[in]   handle  usart handle to operate.
  \return      USART status \ref usart_status_t
*/
usart_status_t csi_usart_get_status(usart_handle_t handle)
{
    usart_status_t status = {0};
    return status;
}

/**
  \brief       control the transmit.
  \param[in]   handle  usart handle to operate.
  \param[in]   1 - enable the transmitter. 0 - disable the transmitter
  \return      error code
*/
int32_t csi_usart_control_tx(usart_handle_t handle, uint32_t enable)
{
    USART_NULL_PARAM_CHK(handle);
    return 0;
}

/**
  \brief       control the receive.
  \param[in]   handle  usart handle to operate.
  \param[in]   1 - enable the receiver. 0 - disable the receiver
  \return      error code
*/
int32_t csi_usart_control_rx(usart_handle_t handle, uint32_t enable)
{
    USART_NULL_PARAM_CHK(handle);
    return 0;
}

/**
  \brief       control the break.
  \param[in]   handle  usart handle to operate.
  \param[in]   1- Enable continuous Break transmission,0 - disable continuous Break transmission
  \return      error code
*/
int32_t csi_usart_control_break(usart_handle_t handle, uint32_t enable)
{
    USART_NULL_PARAM_CHK(handle);
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       flush receive/send data.
  \param[in]   handle usart handle to operate.
  \param[in]   type \ref usart_flush_type_e.
  \return      error code
*/
int32_t csi_usart_flush(usart_handle_t handle, usart_flush_type_e type)
{
    USART_NULL_PARAM_CHK(handle);

    dw_usart_priv_t *usart_priv = handle;
    dw_usart_reg_t *addr = (dw_usart_reg_t *)(usart_priv->base);

    if (type == USART_FLUSH_WRITE) {
        addr->FCR |= DW_FCR_XFIFOR;

        while (addr->FCR & DW_FCR_XFIFOR);
    } else if (type == USART_FLUSH_READ) {
        addr->FCR |= DW_FCR_RFIFOR;

        while (addr->FCR & DW_FCR_RFIFOR);
    } else {
        return ERR_USART(EDRV_PARAMETER);
    }

    return 0;
}

/**
  \brief       control interrupt on/off.
  \param[in]   handle usart handle to operate.
  \param[in]   type \ref usart_intr_type_e.
  \param[in]   flag 0-OFF, 1-ON.
  \return      error code
*/
int32_t csi_usart_interrupt_on_off(usart_handle_t handle, usart_intr_type_e type, int flag)
{
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       Get usart send data count.
  \param[in]   handle  usart handle to operate.
  \return      number of data bytes transferred
*/
uint32_t csi_usart_get_tx_count(usart_handle_t handle)
{
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       Get usart receive data count.
  \param[in]   handle  usart handle to operate.
  \return      number of data bytes transferred
*/
uint32_t csi_usart_get_rx_count(usart_handle_t handle)
{
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       control usart power.
  \param[in]   handle  usart handle to operate.
  \param[in]   state   power state.\ref csi_power_stat_e.
  \return      error code
*/
int32_t csi_usart_power_control(usart_handle_t handle, csi_power_stat_e state)
{
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       config usart flow control type.
  \param[in]   handle  usart handle to operate.
  \param[in]   flowctrl_type   flow control type.\ref usart_flowctrl_type_e.
  \param[in]   tx_flow  The TX flow pin name
  \param[in]   rx_flow  The RX flow pin name
  \return      error code
*/
int32_t csi_usart_config_flowctrl(usart_handle_t handle,
                                  usart_flowctrl_type_e flowctrl_type,
                                  pin_t tx_flow, pin_t rx_flow)
{
    USART_NULL_PARAM_CHK(handle);
    dw_usart_priv_t *usart_priv = handle;
    dw_usart_reg_t *addr = (dw_usart_reg_t *)(usart_priv->base);
    int32_t ret;

    switch (flowctrl_type) {
        case USART_FLOWCTRL_CTS:
            return ERR_USART(EDRV_UNSUPPORTED);

        case USART_FLOWCTRL_RTS:
            return ERR_USART(EDRV_UNSUPPORTED);

        case USART_FLOWCTRL_CTS_RTS:
            ret = target_usart_flowctrl_init(tx_flow, rx_flow, 1);

            if (ret < 0) {
                return ERR_USART(EDRV_PARAMETER);
            }

            WAIT_USART_IDLE(addr);
            addr->MCR |= DW_MCR_AFCE | DW_MCR_RTS;
            break;

        case USART_FLOWCTRL_NONE:
            ret = target_usart_flowctrl_init(tx_flow, rx_flow, 0);

            if (ret < 0) {
                return ERR_USART(EDRV_PARAMETER);
            }

            WAIT_USART_IDLE(addr);
            addr->MCR = 0;
            break;

        default:
            return ERR_USART(EDRV_UNSUPPORTED);
    }

    return 0;
}

/**
  \brief       usart modem control.
  \param[in]   handle  usart handle to operate.
  \param[in]   modem_ctrl   modem control action.\ref usart_modem_ctrl_e.
  \return      error code
*/
int32_t csi_usart_modem_ctrl(usart_handle_t handle, usart_modem_ctrl_e modem_ctrl)
{
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       get usart modem status.
  \param[in]   handle  usart handle to operate.
  \param[in]   modem_ctrl   modem control action.\ref usart_modem_ctrl_e.
  \return      modem status.\ref usart_modem_stat_t.
*/
usart_modem_stat_t csi_usart_get_modem_stat(usart_handle_t handle)
{
    usart_modem_stat_t modem_stat = {0};
    return modem_stat;
}

/**
  \brief       config usart clock Polarity and Phase.
  \param[in]   handle  usart handle to operate.
  \param[in]   cpol    Clock Polarity.\ref usart_cpol_e.
  \param[in]   cpha    Clock Phase.\ref usart_cpha_e.
  \return      error code
*/
int32_t csi_usart_config_clock(usart_handle_t handle, usart_cpol_e cpol, usart_cpha_e cpha)
{
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       config usart guard time.
  \param[in]   handle  usart handle to operate.
  \param[in]   num_of_bits   guard time in number of bit periods.
  \return      error code
*/
int32_t csi_usart_config_guard_time(usart_handle_t handle, uint32_t num_of_bits)
{
    return ERR_USART(EDRV_UNSUPPORTED);
}

/**
  \brief       check if usart is readable(data received).
  \param[in]   handle  usart handle to operate.
  \return      1 - a character can be read, 0 if nothing to read ,negative for error code
*/
int32_t csi_usart_readable(usart_handle_t handle)
{
    USART_NULL_PARAM_CHK(handle);
    dw_usart_priv_t *usart_priv = handle;
    dw_usart_reg_t *addr = (dw_usart_reg_t *)(usart_priv->base);

    if (addr->LSR & LSR_DATA_READY) {
        return 1;
    } else {
        return 0;
    }
}

/**
  \brief       check if usart is writable(free for data sending).
  \param[in]   handle  usart handle to operate.
  \return      1 - a character can be written, 0 -  cannot be written ,negative for error code
*/
int32_t csi_usart_writable(usart_handle_t handle)
{
    USART_NULL_PARAM_CHK(handle);
    dw_usart_priv_t *usart_priv = handle;
    dw_usart_reg_t *addr = (dw_usart_reg_t *)(usart_priv->base);

    if (addr->LSR & DW_LSR_TRANS_EMPTY) {
        return 1;
    } else {
        return 0;
    }
}