rt-thread-official/libcpu/arm/s3c24x0/serial.c

292 lines
7.3 KiB
C

/*
* Copyright (c) 2006-2018, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2006-03-13 Bernard first version
* 2009-04-20 yi.qiu modified according bernard's stm32 version
*/
#include <rtthread.h>
#include "serial.h"
/**
* @addtogroup S3C24X0
*/
/*@{*/
/* RT-Thread Device Interface */
/**
* This function initializes serial
*/
static rt_err_t rt_serial_init(rt_device_t dev)
{
struct serial_device* uart = (struct serial_device*) dev->user_data;
if (!(dev->flag & RT_DEVICE_FLAG_ACTIVATED))
{
if (dev->flag & RT_DEVICE_FLAG_INT_RX)
{
rt_memset(uart->int_rx->rx_buffer, 0,
sizeof(uart->int_rx->rx_buffer));
uart->int_rx->read_index = uart->int_rx->save_index = 0;
}
if (dev->flag & RT_DEVICE_FLAG_INT_TX)
{
rt_memset(uart->int_tx->tx_buffer, 0,
sizeof(uart->int_tx->tx_buffer));
uart->int_tx->write_index = uart->int_tx->save_index = 0;
}
dev->flag |= RT_DEVICE_FLAG_ACTIVATED;
}
return RT_EOK;
}
/* save a char to serial buffer */
static void rt_serial_savechar(struct serial_device* uart, char ch)
{
rt_base_t level;
/* disable interrupt */
level = rt_hw_interrupt_disable();
uart->int_rx->rx_buffer[uart->int_rx->save_index] = ch;
uart->int_rx->save_index ++;
if (uart->int_rx->save_index >= UART_RX_BUFFER_SIZE)
uart->int_rx->save_index = 0;
/* if the next position is read index, discard this 'read char' */
if (uart->int_rx->save_index == uart->int_rx->read_index)
{
uart->int_rx->read_index ++;
if (uart->int_rx->read_index >= UART_RX_BUFFER_SIZE)
uart->int_rx->read_index = 0;
}
/* enable interrupt */
rt_hw_interrupt_enable(level);
}
static rt_err_t rt_serial_open(rt_device_t dev, rt_uint16_t oflag)
{
RT_ASSERT(dev != RT_NULL);
return RT_EOK;
}
static rt_err_t rt_serial_close(rt_device_t dev)
{
RT_ASSERT(dev != RT_NULL);
return RT_EOK;
}
static rt_size_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
{
rt_uint8_t* ptr;
rt_err_t err_code;
struct serial_device* uart;
ptr = buffer;
err_code = RT_EOK;
uart = (struct serial_device*)dev->user_data;
if (ptr == RT_NULL)
{
err_code = -RT_ENOMEM;
rt_set_errno(err_code);
return -RT_ENOMEM;
}
if (dev->flag & RT_DEVICE_FLAG_INT_RX)
{
rt_base_t level;
/* interrupt mode Rx */
while (size)
{
if (uart->int_rx->read_index != uart->int_rx->save_index)
{
*ptr++ = uart->int_rx->rx_buffer[uart->int_rx->read_index];
size --;
/* disable interrupt */
level = rt_hw_interrupt_disable();
uart->int_rx->read_index ++;
if (uart->int_rx->read_index >= UART_RX_BUFFER_SIZE)
uart->int_rx->read_index = 0;
/* enable interrupt */
rt_hw_interrupt_enable(level);
}
else
{
/* set error code */
err_code = -RT_EEMPTY;
break;
}
}
}
else
{
/* polling mode */
while ((rt_uint32_t)ptr - (rt_uint32_t)buffer < size)
{
while (uart->uart_device->ustat & USTAT_RCV_READY)
{
*ptr = uart->uart_device->urxh & 0xff;
ptr ++;
}
}
}
/* set error code */
rt_set_errno(err_code);
return (rt_uint32_t)ptr - (rt_uint32_t)buffer;
}
static rt_size_t rt_serial_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
{
rt_uint8_t* ptr;
rt_err_t err_code;
struct serial_device* uart;
err_code = RT_EOK;
ptr = (rt_uint8_t*)buffer;
uart = (struct serial_device*)dev->user_data;
if (ptr == RT_NULL)
{
err_code = -RT_ENOMEM;
rt_set_errno(err_code);
return -RT_ENOMEM;
}
if (dev->flag & RT_DEVICE_FLAG_INT_TX)
{
/* interrupt mode Tx */
while (uart->int_tx->save_index != uart->int_tx->write_index)
{
/* save on tx buffer */
uart->int_tx->tx_buffer[uart->int_tx->save_index] = *ptr++;
-- size;
/* move to next position */
uart->int_tx->save_index ++;
/* wrap save index */
if (uart->int_tx->save_index >= UART_TX_BUFFER_SIZE)
uart->int_tx->save_index = 0;
}
/* set error code */
if (size > 0)
err_code = -RT_EFULL;
}
else
{
/* polling mode */
while (size)
{
/*
* to be polite with serial console add a line feed
* to the carriage return character
*/
if (*ptr == '\n' && (dev->flag & RT_DEVICE_FLAG_STREAM))
{
while (!(uart->uart_device->ustat & USTAT_TXB_EMPTY));
uart->uart_device->utxh = '\r';
}
while (!(uart->uart_device->ustat & USTAT_TXB_EMPTY));
uart->uart_device->utxh = (*ptr & 0xFF);
++ptr;
--size;
}
}
/* set error code */
rt_set_errno(err_code);
return (rt_uint32_t)ptr - (rt_uint32_t)buffer;
}
static rt_err_t rt_serial_control(rt_device_t dev, int cmd, void *args)
{
RT_ASSERT(dev != RT_NULL);
switch (cmd)
{
case RT_DEVICE_CTRL_SUSPEND:
/* suspend device */
dev->flag |= RT_DEVICE_FLAG_SUSPENDED;
break;
case RT_DEVICE_CTRL_RESUME:
/* resume device */
dev->flag &= ~RT_DEVICE_FLAG_SUSPENDED;
break;
}
return RT_EOK;
}
/*
* serial register
*/
rt_err_t rt_hw_serial_register(rt_device_t device, const char* name, rt_uint32_t flag, struct serial_device *serial)
{
RT_ASSERT(device != RT_NULL);
device->type = RT_Device_Class_Char;
device->rx_indicate = RT_NULL;
device->tx_complete = RT_NULL;
device->init = rt_serial_init;
device->open = rt_serial_open;
device->close = rt_serial_close;
device->read = rt_serial_read;
device->write = rt_serial_write;
device->control = rt_serial_control;
device->user_data = serial;
/* register a character device */
return rt_device_register(device, name, RT_DEVICE_FLAG_RDWR | flag);
}
/* ISR for serial interrupt */
void rt_hw_serial_isr(rt_device_t device)
{
struct serial_device* uart = (struct serial_device*) device->user_data;
/* interrupt mode receive */
RT_ASSERT(device->flag & RT_DEVICE_FLAG_INT_RX);
/* save on rx buffer */
while (uart->uart_device->ustat & USTAT_RCV_READY)
{
rt_serial_savechar(uart, uart->uart_device->urxh & 0xff);
}
/* invoke callback */
if (device->rx_indicate != RT_NULL)
{
rt_size_t rx_length;
/* get rx length */
rx_length = uart->int_rx->read_index > uart->int_rx->save_index ?
UART_RX_BUFFER_SIZE - uart->int_rx->read_index + uart->int_rx->save_index :
uart->int_rx->save_index - uart->int_rx->read_index;
device->rx_indicate(device, rx_length);
}
}
/*@}*/