Linux2.6.32下SPI驱动的移植如下图所示：

下面需要修改部分内核代码，具体操作如下：

1.  修改arch/arm/mach-s3c2440/mach-mini2440.c文件

在include头文件代码行之后增加如下代码

//spi  add by shiguang

#include

#include

static struct spi_board_info s3c2410_spi0_board[] = {

[0] = {

.modalias = "spidev",

.bus_num        = 0,

.chip_select        = 0,

.irq = IRQ_EINT9,

.max_speed_hz         = 500*1000,

},

};

static struct s3c2410_spi_info s3c2410_spi0_platdata = {

.pin_cs = S3C2410_GPG(2),

.num_cs = 1,

.bus_num = 0,

};

//end add spi

然后在函数__initmini2440_machine_init的开头增加下列代码

//spi add by shiguang

s3c_device_spi0.dev.platform_data=&s3c2410_spi0_platdata;

spi_register_board_info(s3c2410_spi0_board,ARRAY_SIZE(s3c2410_spi0_board));

//end spi

在mini2440_devices数组的最后中添加

&s3c_device_spi0,// add by shiguang

2.修改drivers/spi/spi_s3c24xx.c文件

在文件开头增加下列代码

//add by shiguang

#include

在s3c24xx_spi_initialsetup函数结尾增加下列代码

// add by shiguang

s3c2410_gpio_cfgpin(hw->pdata->pin_cs,S3C2410_GPIO_OUTPUT);

s3c2410_gpio_cfgpin(0x8B, S3C2410_GPIO_SFN2);

s3c2410_gpio_cfgpin(0x8C, S3C2410_GPIO_SFN2);

s3c2410_gpio_cfgpin(0x8D, S3C2410_GPIO_SFN2);

// end add

3. 最后重新编译内核

重启mini2440，查看/dev下的设备文件

[root@ShiGuang /]# ls /dev/spidev0.0 -l

crw-rw----    1 root     root     153,   0 Jan  1 08:00 /dev/spidev0.0

[root@ShiGuang /]#

4. 应用程序测试

测设程序取至Linux源码包下的/home/youshan/linux-2.6.32.2/Documentation/spi/spidev_test.c ，这里我再把它贴一遍。

点击(此处)折叠或打开

/*

* SPI testing utility (using spidev driver)

*

* Copyright (c) 2007 MontaVista Software, Inc.

* Copyright (c) 2007 Anton Vorontsov

*

* 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

#include

#include

#include

#include

#include

#include

#include

#include

#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))

static void pabort(const char *s)

{

perror(s);

abort();

}

static const char *device = "/dev/spidev1.1";

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;

}

只需将mini2440的SPI rx和tx短接就可以收到数据。结果如下图所示：

测试完毕！OVER！

转载自：http://blog.csdn.net/stephen_yu/article/details/7205671