驱动移植pcDuino的linux移植五gpio驱动开发

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mb5fcf3d5431d90 2013-05-25 14:42:00

文章标签 linux #include 原理图测试程序 5e 文章分类 代码人生

文章结束给大家来个程序员笑话：[M]

调试完pcDuino的led裸板程序，再调pcDuino基于linux内核的gpio驱动开辟，之前的问题水到渠成。本文是在pcDuino的linux移植四简单驱动开辟的基础上，做GPIO驱动开辟。然后写一个应用测试程序，通过敲命令控制pcduino的TX led亮、灭。同时如果你GPIO4、GPIO5接个LED，也会随着亮、灭。

开辟环境：

系统：ubuntu 10.04.4

单板：pcDuino

编译器：arm-2009q3-67-arm-none-linux-gnueabi-i686-pc-linux-gnu.tar.bz2

目标：敲命令控制pcDuino上的TX_LED亮、灭

一、硬件介绍

仔细看pcDuino上的原理图和pcDuino的手册，发明二者不是完全对应的，还是以原理图为准。根据原理图晓得TX_LED是接到PH15上，可以当作普通IO口用，不需要连跳线

驱动移植pcDuino的linux移植五gpio驱动开发_#include

二、编写GPIO驱动代码

主要包括2部份，驱动代码first_drv.c和应用测试程序firstdrvtest.c以及Makefile。

驱动代码first_drv.c

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <asm/uaccess.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <mach/gpio.h>
#include <mach/hardware.h>
#include <linux/device.h>

static struct class *firstdrv_class;
static struct class_device *firstdrv_class_dev;

volatile unsigned long *gphcfg1;//0x100 ph9 [6:4]001
volatile unsigned long *gphdat; //0x10c
static int first_drv_open(struct inode *inode, struct file *file)
{
  printk("first_drv_open\n");
  /* 配置GPh9为输出引脚 gpio4*/
  *gphcfg1 |= ((0x1<<4)|(0x1<<8)|(0X1<<28));
  return 0;
}

static ssize_t first_drv_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
{
  int val;
  printk("first_drv_write\n");
  copy_from_user(&val, buf, count); //  copy_to_user();

  if (val == 1)
  {
    // 点灯
    *gphdat &= ~((0X1<<9)|(0X1<<10)|(1<<15));
  }
  else
  {
    // 灭灯
    *gphdat |= ((0X1<<9)|(0X1<<10)|(1<<15));
  }

  return 0;
}

static struct file_operations first_drv_fops ={
  .owner = THIS_MODULE,
  .open  = first_drv_open,
  .write = first_drv_write,
};

int major;
static int first_drv_init(void)
{
  major = register_chrdev(0, "first_drv", &first_drv_fops);
  firstdrv_class = class_create(THIS_MODULE, "firstdrv");
  firstdrv_class_dev = device_create(firstdrv_class,NULL,MKDEV(major, 0), NULL, "xyz");
  gphcfg1 = (volatile unsigned long *)ioremap(0x01c20900, 16);
  gphdat = (volatile unsigned long *)ioremap(0x01c2090c, 16);//gphcfg1 + 3;
  return 0;
}

static void first_drv_exit(void)
{
  unregister_chrdev(major,"first_drv");
  device_unregister(firstdrv_class_dev);
  class_destroy(firstdrv_class);
  iounmap(gphcfg1);

iounmap(gphdat);
}

module_init(first_drv_init);
module_exit(first_drv_exit);

MODULE_LICENSE("GPL");

文件Makefile：

KERN_DIR = /home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0

all:
  make -C $(KERN_DIR) M=`pwd` modules

clean:
  make -C $(KERN_DIR) M=`pwd`  modules clean
  rm -rf modules.order

obj-m += first_drv.o

应用测试程序firstdrvtest.c：

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>

/* firstdrvtest on
  * firstdrvtest off
  */
int main(int argc, char **argv)
{
  int fd;
  int val = 1;
  fd = open("/dev/xyz", O_RDWR);
  if (fd < 0)
  {
    printf("can't open!\n");
  }
  if (argc != 2)
  {
    printf("Usage :\n");
    printf("%s <on|off>\n", argv[0]);
    return 0;
  }

  if (strcmp(argv[1], "on") == 0)
  {
    val  = 1;
  }
  else
  {
    val = 0;
  }

  write(fd, &val, 4);
  return 0;
}

三、编译测试

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change@change:~/Si/A10/2_led$ cd ../pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/

change@change:~/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv$ ls

first_drv.c first_drv.mod.c first_drv.o firstdrvtest.c modules.order

first_drv.ko first_drv.mod.o firstdrvtest Makefile Module.symvers

change@change:~/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv$ make clean

make -C /home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0 M=`pwd` modules clean

make[1]: Entering directory `/home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0'

LD /home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/built-in.o

CC [M] /home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/first_drv.o

/home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/first_drv.c: In function 'first_drv_write':

/home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/first_drv.c:30: warning: ignoring return value of 'copy_from_user', declared with attribute warn_unused_result

/home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/first_drv.c: In function 'first_drv_init':

/home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/first_drv.c:57: warning: assignment from incompatible pointer type

/home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/first_drv.c: In function 'first_drv_exit':

/home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/first_drv.c:66: warning: passing argument 1 of 'device_unregister' from incompatible pointer type

include/linux/device.h:692: note: expected 'struct device *' but argument is of type 'struct class_device *'

Building modules, stage 2.

MODPOST 1 modules

CC /home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/first_drv.mod.o

LD [M] /home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/first_drv.ko

CLEAN /home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/.tmp_versions

CLEAN /home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv/Module.symvers

make[1]: Leaving directory `/home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0'

rm -rf modules.order

change@change:~/Si/A10/pcduino/linux-sunxi-sunxi-3.0/drivers/mydrv/led_drv$ make

make -C /home/change/Si/A10/pcduino/linux-sunxi-sunxi-3.0 M=`pwd` modules