rt-thread/bsp/hifive1/drivers/drv_usart.c

126 lines
3.1 KiB
C
Raw Normal View History

2018-05-30 22:17:25 +08:00
/*
* File : drv_usart.c
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2006 - 2012, RT-Thread Development Team
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Change Logs:
* Date Author Notes
*/
#include <rtdevice.h>
#include <encoding.h>
#include <platform.h>
#include <interrupt.h>
static void usart_handler(int vector, void *param)
{
rt_hw_serial_isr((struct rt_serial_device *)param, RT_SERIAL_EVENT_RX_IND);
}
static rt_err_t usart_configure(struct rt_serial_device *serial,
struct serial_configure *cfg)
{
RT_ASSERT(serial != RT_NULL);
RT_ASSERT(cfg != RT_NULL);
GPIO_REG(GPIO_IOF_SEL) &= ~IOF0_UART0_MASK;
GPIO_REG(GPIO_IOF_EN) |= IOF0_UART0_MASK;
UART0_REG(UART_REG_DIV) = get_cpu_freq() / cfg->baud_rate - 1;
UART0_REG(UART_REG_TXCTRL) |= UART_TXEN;
UART0_REG(UART_REG_RXCTRL) |= UART_RXEN;
UART0_REG(UART_REG_IE) = UART_IP_RXWM;
return RT_EOK;
}
static rt_err_t usart_control(struct rt_serial_device *serial,
int cmd, void *arg)
{
RT_ASSERT(serial != RT_NULL);
switch (cmd)
{
case RT_DEVICE_CTRL_CLR_INT:
break;
case RT_DEVICE_CTRL_SET_INT:
break;
}
return RT_EOK;
}
static int usart_putc(struct rt_serial_device *serial, char c)
{
while (UART0_REG(UART_REG_TXFIFO) & 0x80000000) ;
UART0_REG(UART_REG_TXFIFO) = c;
return 0;
}
static int usart_getc(struct rt_serial_device *serial)
{
rt_int32_t val = UART0_REG(UART_REG_RXFIFO);
if (val > 0)
return (rt_uint8_t)val;
else
return -1;
}
static struct rt_uart_ops ops =
{
usart_configure,
usart_control,
usart_putc,
usart_getc,
};
static struct rt_serial_device serial =
{
.ops = &ops,
.config.baud_rate = BAUD_RATE_115200,
.config.bit_order = BIT_ORDER_LSB,
.config.data_bits = DATA_BITS_8,
.config.parity = PARITY_NONE,
.config.stop_bits = STOP_BITS_1,
.config.invert = NRZ_NORMAL,
.config.bufsz = RT_SERIAL_RB_BUFSZ,
};
int rt_hw_uart_init(void)
{
rt_hw_serial_register(
&serial,
"dusart",
RT_DEVICE_FLAG_STREAM
| RT_DEVICE_FLAG_RDWR
| RT_DEVICE_FLAG_INT_RX, RT_NULL);
rt_hw_interrupt_install(
INT_UART0_BASE,
usart_handler,
(void *) & (serial.parent),
"uart interrupt");
rt_hw_interrupt_unmask(INT_UART0_BASE);
return 0;
}
INIT_BOARD_EXPORT(rt_hw_uart_init);