从内核访问USART以发送和接收

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/serial_core.h>
#include <linux/serial_reg.h>
#include <linux/serial.h>

static struct uart_port uart_port;

static int __init uart_init(void) {
    struct uart_driver *uart_drv = &uart_driver;
    struct uart_state *state;

    uart_drv->owner = THIS_MODULE;
    uart_drv->driver_name = "uart";
    uart_drv->dev_name = "ttyS0";
    uart_drv->major = 204;
    uart_drv->minor = 64;
    uart_drv->nr = 1;

    state = uart_get_state(uart_drv, 0);
    if (!state) {
        printk(KERN_ERR "Failed to get UART state\n");
        return -ENODEV;
    }

    uart_port.port = state->port[0];
    uart_port.iobase = 0x3F8; // COM1 base address on x86
    uart_port.irq = 4; // COM1 IRQ on x86
    uart_port.uartclk = 1843200; // 1.8432 MHz

    if (uart_add_one_port(uart_drv, &uart_port) < 0) {
        printk(KERN_ERR "Failed to add UART port\n");
        return -ENODEV;
    }

    printk(KERN_INFO "UART driver loaded\n");
    return 0;
}

static void __exit uart_exit(void) {
    struct uart_driver *uart_drv = &uart_driver;

    uart_remove_one_port(uart_drv, &uart_port);
    uart_drv->unregister(uart_drv);
    printk(KERN_INFO "UART driver unloaded\n");
}

module_init(uart_init);
module_exit(uart_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Your Name");
MODULE_DESCRIPTION("Simple UART driver");