linux 模拟spi驱动

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/gpio.h>
#include <linux/spi/spidev.h>

#define MOSI_PIN 10
#define MISO_PIN 11
#define SCK_PIN 12
#define SS_PIN 13

static int spi_transfer(struct spi_device *spi, struct spi_message *msg)
{
    // 模拟SPI传输的代码
    return 0;
}

static struct spi_master *master;

static int __init spi_init(void)
{
    master = spi_alloc_master(&pdev->dev, sizeof(struct spi_master));
    if (!master)
        return -ENOMEM;

    master->transfer = spi_transfer;
    master->num_chipselect = 1;
    master->bus_num = 0;

    gpio_request(MOSI_PIN, "spi_mosi");
    gpio_request(MISO_PIN, "spi_miso");
    gpio_request(SCK_PIN, "spi_sck");
    gpio_request(SS_PIN, "spi_ss");

    gpio_direction_output(MOSI_PIN, 0);
    gpio_direction_input(MISO_PIN);
    gpio_direction_output(SCK_PIN, 0);
    gpio_direction_output(SS_PIN, 1);

    spi_register_master(master);
    return 0;
}

static void __exit spi_exit(void)
{
    spi_unregister_master(master);
    gpio_free(MOSI_PIN);
    gpio_free(MISO_PIN);
    gpio_free(SCK_PIN);
    gpio_free(SS_PIN);
}

module_init(spi_init);
module_exit(spi_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Linux SPI Simulation Driver");