tq2440 pwm 驱动

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基于tq2440开发板，内核2.6.30

功能

神奇了，加了几条打印语句后蜂鸣器就叫了。

估计是tcon 的写入速度比较慢吧，需要点延时。

真心伤不起啊

还有就是不知道为什么tcon  寄存器值的输出好像不对劲

这个pwm 设置其实和其他的单片机也差不多，

只不过多了个死区的概念，就是防止电器驱动时候的开关同时开启

当tcnt 和tcnp 的相等时候电平反转。

tcnt 为递减计数器

为什么出现奇怪数据的原因 是寄存器没有清零，

虽然它默认是0 但是当你错误操作，板子没有重启，

可能那寄存器的值就改变了。

没有测过时间，闲麻烦，而且蜂鸣器的接口好像没有外接。算了 。将就了。

没有写成定时器中断的原因是中断函数找不到啊，咋写。。。。

2012年7月10日22:16:37

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#include <linux/miscdevice.h>

#include <linux/delay.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/init.h>

#include <linux/mm.h>

#include <linux/fs.h>

#include <linux/types.h>

#include <linux/delay.h>

#include <linux/moduleparam.h>

#include <linux/slab.h>

#include <linux/errno.h>

#include <linux/ioctl.h>

#include <linux/cdev.h>

#include <linux/string.h>

#include <linux/list.h>

#include <linux/pci.h>

#include <linux/poll.h>

#include <linux/interrupt.h>

#include <linux/platform_device.h>

#include <linux/irq.h>

#include <linux/interrupt.h>

#include <linux/clk.h>

#include <mach/regs-gpio.h>

#include <mach/hardware.h>

#include <asm/irq.h>

#include <asm/uaccess.h>

#include <asm/atomic.h>

#include <asm/unistd.h>

#include <plat/regs-timer.h>

#define DEVICE_NAME "driver_pwm"

//gpb0 tout0

//

volatile unsigned long *gpbcon = NULL;

volatile unsigned long *gpbdat = NULL;

volatile unsigned long *tcfg0 = NULL; //用来设置预分频

volatile unsigned long *tcfg1 = NULL; //用来设置分频

volatile unsigned long *tcon  = NULL; //定时器控制器

volatile unsigned long *tcntb0 = NULL; //计数缓冲寄存器

volatile unsigned long *tcmpb0 = NULL; //比较缓冲寄存器

volatile unsigned long *tcnto0 = NULL; //计数观察寄存器

//*gpbdat &= ~((1<<5) );

// ------------------- OPEN ------------------------

ssize_t drive_open (struct inode * inode ,struct file * file)

{

*gpbcon &=~(3<<0*2);

*gpbcon |= (2<<0*2);//设置b0 为 tout0

//*gpbcon &= ~( (3<<0*2)|(3<<5*2) );

//*gpbcon |= (1<<0*2)|(1<<5*2);

printk("-----------------drive open ok----------------\n");

return 0;

}

// ------------------- RELEASE/CLOSE ---------------

ssize_t drive_release (struct inode  * inode ,struct file * file)

{

printk("-----------------drive close ok----------------\n");

return 0;

}

// ------------------- READ ------------------------

ssize_t drive_read (struct file * file ,char * buf, size_t count, loff_t * f_ops)

{

printk("-----------------drive read ok----------------\n");

//copy_to_user( buf,(const void *)press_cnt,sizeof(press_cnt) );

return 0;

}

// ------------------- WRITE -----------------------

ssize_t drive_write (struct file * file ,const char * buf, size_t count, loff_t * f_ops)

{

printk("-----------------drive write ok----------------\n");

return 0;

}

// ------------------- IOCTL -----------------------

ssize_t drive_ioctl (struct inode * inode ,struct file * file, unsigned int cmd, unsigned long arg)

{

struct clk *clk_p;

       unsigned long pclk;

unsigned long tcnt;

printk("-----------------drive ioctl ok----------------\n");

//if(cmd==0)

// return 0;

//定时器时钟频率=pclk /( 预分频器的值+1) / 分频器

//62.5k

*tcfg0 &= ~0xff;//定时器0预分配清零

*tcfg0 |=(50-1);//预分频 50

*tcfg1 &= ~0xf;//定时器0 mux 输入分频清零

*tcfg1 |=3; //mux 分频 16

 clk_p = clk_get(NULL, "pclk"); 

        pclk = clk_get_rate(clk_p);

tcnt = (pclk/50/16)/10;  

printk("pclk =  %d\n",pclk);

printk("tcnt =  %d\n",tcnt);

*tcntb0 &=0x0000;//16位寄存器

*tcmpb0 &=0x0000;

*tcntb0 |= 1000;

*tcmpb0|=500;

//*tcon &=0x0;

// printk("tcon=%d\n",*tcon);

printk("tcntb0=%d\n",*tcntb0);

 printk("tcmpb0=%d\n",*tcmpb0);

 

*tcon &= ~0x1f;//清零

// printk("tcon=%d\n",*tcon);

msleep(10);

//第一次必须手动更新

       *tcon |= 0xb;  //关闭死区、自动重载、关反相器、手动更新TCNTB0&TCMPB0、启动定时器0

//1011

//printk("tcon=%d\n",*tcon);

msleep(10);

 *tcon &= ~2;  //清除定时器0的手动更新位

 

//printk("tcon=%d\n",*tcon);

 printk("tcfg0=%d\n",*tcfg0);

 printk("tcfg1=%d\n",*tcfg1);

 printk("tcntb0=%d\n",*tcntb0);

 printk("tcmpb0=%d\n",*tcmpb0);

 printk("tcon=%d\n",*tcon);

 

//-----------------------------------------------------

/*

pclk =  50000000

tcnt =  6250

tcon=5242889

tcfg0=561

tcfg1=3

tcntb0=7295

tcmpb0=7295

tcon=5242889

pclk =  50000000

tcnt =  6250

tcntb0=8191

tcmpb0=7679

tcfg0=561

tcfg1=3

tcntb0=8191

tcmpb0=7679

tcon=5242889

*gpbdat |= 1<<0;

*gpbdat |= 1<<5;

msleep(500);

*gpbdat &= ~(1<<0);

*gpbdat &= ~(1<<5);

*/

//-----------------------------------------------------

//msleep(500);

return 0;

}

// -------------------------------------------------

static struct file_operations drive_ops ={

.owner  = THIS_MODULE,

.open   = drive_open,

.read    = drive_read,

.write   = drive_write,

.ioctl    = drive_ioctl,

.release = drive_release,

};

static struct miscdevice misc = {

.minor = MISC_DYNAMIC_MINOR,

.name = DEVICE_NAME,

.fops = &drive_ops,

};

static int __init init_drive(void)  

{

int ret;

ret = misc_register(&misc);

gpbcon = (volatile unsigned long *)ioremap(0x56000010,32);

gpbdat = (volatile unsigned long *)ioremap(0x56000014, 32);

tcfg0    = (volatile unsigned long *)ioremap(0x51000000, 4);

tcfg1    = (volatile unsigned long *)ioremap(0x51000004, 4);

tcon     = (volatile unsigned long *)ioremap(0x51000008, 4);

tcntb0  = (volatile unsigned long *)ioremap(0x5100000c, 4);

tcmpb0 = (volatile unsigned long *)ioremap(0x51000010, 4);

tcnto0  = (volatile unsigned long *)ioremap(0x51000014, 4);

printk("-----------------drive button init ok----------------\n");

return 0;

}

static void __exit exit_drive(void)

{

*tcon &=~1;

misc_deregister(&misc);

printk("-----------------drive button exit ok----------------\n");

}

module_init(init_drive);

module_exit(exit_drive);

MODULE_LICENSE("GPL");

//--------------------------------------应用测试程序----------------------------------------------------

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include <fcntl.h>      // open() close()

#include <unistd.h>     // read() write()

#define DEVICE_NAME "/dev/driver_pwm"

//------------------------------------- main ---------------------------------------------

int main(int argc, char **argv)

{

int fd,ret;

       fd = open(DEVICE_NAME, O_RDWR);

 

if (fd == -1)

{

printf("can't open device mknod %s c zhu ci \n",DEVICE_NAME);

return 0;

}

ioctl(fd, 1);

while(1)

{

;

}

        // close 

ret = close(fd);

        return 0;

}// end main