前段时间布置的任务是弄w5500的驱动，w5500本身硬件就具有tcp/ip协议，这样就省去了再把tcp协议栈移植到Uclinux的麻烦，而且我的存储空间一直是不够用的，所以选择w5500作为一个网卡来使用是再合适不过。

仔细看了一遍w5500的说明pdf，要使它能正常在Uclinux的环境下运行是要正确设置它的相关寄存器，而要设置它的寄存器，是要用spi接口与spi传输协议来设置，所以第一步的工作是要先添加Uclinux的spi驱动，庆幸的是spi驱动也已经由这个内核的开发小组所编写出来了，我们只要在内核设置里面勾选相关选项即可。

Device Drivers and enable SPI Support. Then from SPI Support enable STM32 SPI Controller and User mode spi device driver support

system Type->stm32 IO interfaces

>Enable STM32 spi1 port

<div>

这里写图片描述

设置完成后，运行内核，出现如下图的提示，证明spidev驱动已经成功添加进内核了。

在Documentation/spi/spidev_test.c中有spi驱动的测试代码如下：

/** SPI testing utility (using spidev driver)** Copyright (c) 2007  MontaVista Software, Inc.* Copyright (c) 2007  Anton Vorontsov <avorontsov@ru.mvista.com>** 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.** Cross-compile with cross-gcc -I/path/to/cross-kernel/include*/#include <stdint.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <getopt.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/types.h>
#include <linux/spi/spidev.h>#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))static void pabort(const char *s)
{perror(s);abort();
}static const char *device = "/dev/spidev0.0";
static uint8_t mode;
static uint8_t bits = 8;
static uint32_t speed = 500000;
static uint16_t delay;static void transfer(int fd)
{int ret;uint8_t tx[] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,0x40, 0x00, 0x00, 0x00, 0x00, 0x95,0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,0xDE, 0xAD, 0xBE, 0xEF, 0xBA, 0xAD,0xF0, 0x0D,};uint8_t rx[ARRAY_SIZE(tx)] = {0, };struct spi_ioc_transfer tr = {.tx_buf = (unsigned long)tx,.rx_buf = (unsigned long)rx,.len = ARRAY_SIZE(tx),.delay_usecs = delay,.speed_hz = speed,.bits_per_word = bits,};ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);if (ret == 1)pabort("can't send spi message");for (ret = 0; ret < ARRAY_SIZE(tx); ret++) {if (!(ret % 6))puts("");printf("%.2X ", rx[ret]);}puts("");
}static void print_usage(const char *prog)
{printf("Usage: %s [-DsbdlHOLC3]\n", prog);puts("  -D --device   device to use (default /dev/spidev1.1)\n""  -s --speed    max speed (Hz)\n""  -d --delay    delay (usec)\n""  -b --bpw      bits per word \n""  -l --loop     loopback\n""  -H --cpha     clock phase\n""  -O --cpol     clock polarity\n""  -L --lsb      least significant bit first\n""  -C --cs-high  chip select active high\n""  -3 --3wire    SI/SO signals shared\n");exit(1);
}static void parse_opts(int argc, char *argv[])
{while (1) {static const struct option lopts[] = {{ "device",  1, 0, 'D' },{ "speed",   1, 0, 's' },{ "delay",   1, 0, 'd' },{ "bpw",     1, 0, 'b' },{ "loop",    0, 0, 'l' },{ "cpha",    0, 0, 'H' },{ "cpol",    0, 0, 'O' },{ "lsb",     0, 0, 'L' },{ "cs-high", 0, 0, 'C' },{ "3wire",   0, 0, '3' },{ "no-cs",   0, 0, 'N' },{ "ready",   0, 0, 'R' },{ NULL, 0, 0, 0 },};int c;c = getopt_long(argc, argv, "D:s:d:b:lHOLC3NR", lopts, NULL);if (c == -1)break;switch (c) {case 'D':device = optarg;break;case 's':speed = atoi(optarg);break;case 'd':delay = atoi(optarg);break;case 'b':bits = atoi(optarg);break;case 'l':mode |= SPI_LOOP;break;case 'H':mode |= SPI_CPHA;break;case 'O':mode |= SPI_CPOL;break;case 'L':mode |= SPI_LSB_FIRST;break;case 'C':mode |= SPI_CS_HIGH;break;case '3':mode |= SPI_3WIRE;break;case 'N':mode |= SPI_NO_CS;break;case 'R':mode |= SPI_READY;break;default:print_usage(argv[0]);break;}}
}int main(int argc, char *argv[])
{int ret = 0;int fd;parse_opts(argc, argv);fd = open(device, O_RDWR);if (fd < 0)pabort("can't open device");/** spi mode*/ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);if (ret == -1)pabort("can't set spi mode");ret = ioctl(fd, SPI_IOC_RD_MODE, &mode);if (ret == -1)pabort("can't get spi mode");/** bits per word*/ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);if (ret == -1)pabort("can't set bits per word");ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);if (ret == -1)pabort("can't get bits per word");/** max speed hz*/ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);if (ret == -1)pabort("can't set max speed hz");ret = ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed);if (ret == -1)pabort("can't get max speed hz");printf("spi mode: %d\n", mode);printf("bits per word: %d\n", bits);printf("max speed: %d Hz (%d KHz)\n", speed, speed/1000);transfer(fd);close(fd);return ret;
}