Linux2.6.32下SPI驅動的移植如下圖所示:
下面需要修改部分內核代碼,具體操作如下:
1.? 修改arch/arm/mach-s3c2440/mach-mini2440.c文件
在include頭文件代碼行之后增加如下代碼
spi設備驅動。//spi??add?by?shiguang
#include?
#include?
static?struct?spi_board_info?s3c2410_spi0_board[]?=?{
[0]?=?{
uart驅動,.modalias?=?"spidev",
.bus_num????????=?0,
.chip_select????????=?0,
.irq?=?IRQ_EINT9,
.max_speed_hz?????????=?500*1000,
SPI驅動,},
};
static?struct?s3c2410_spi_info?s3c2410_spi0_platdata?=?{
.pin_cs?=?S3C2410_GPG(2),
.num_cs?=?1,
freebsd centos?.bus_num?=?0,
};
//end?add?spi
然后在函數__initmini2440_machine_init的開頭增加下列代碼
//spi add by shiguang
spi程序?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數組的最后中添加
&s3c_device_spi0,// add by shiguang
vim encoding?2.修改drivers/spi/spi_s3c24xx.c文件
在文件開頭增加下列代碼
//add by shiguang
#include
在s3c24xx_spi_initialsetup函數結尾增加下列代碼
docker dpdk、// 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);
jdbc.driver,// end add
3. 最后重新編譯內核
重啟mini2440,查看/dev下的設備文件
[root@ShiGuang /]# ls /dev/spidev0.0 -l
crw-rw---- ? ?1 root ? ? root ? ? 153, ? 0 Jan ?1 08:00 /dev/spidev0.0
vim 上一頁下一頁、[root@ShiGuang /]#
4. 應用程序測試
測設程序取至Linux源碼包下的/home/youshan/linux-2.6.32.2/Documentation/spi/spidev_test.c ,這里我再把它貼一遍。
點擊(此處)折疊或打開
/*
linux spi驅動實例,* SPI testing utility (using spidev driver)
*
* Copyright (c) 2007 MontaVista Software, Inc.
* Copyright (c) 2007 Anton Vorontsov
*
設備引腳 linux 設備結構。* 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
spi_config_clock?*/
#include
#include
#include
#include
Linux spi從模式寫法,#include
#include
#include
#include
#include
linux設備驅動開發步驟。#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;
}
只需將mini2440的SPI rx和tx短接就可以收到數據。結果如下圖所示:
測試完畢!OVER!
轉載自:http://blog.csdn.net/stephen_yu/article/details/7205671
版权声明:本站所有资料均为网友推荐收集整理而来,仅供学习和研究交流使用。
工作时间:8:00-18:00
客服电话
电子邮件
admin@qq.com
扫码二维码
获取最新动态