UTS6710/drivers/wdog/wdog.c

#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/cdev.h>
#include <linux/version.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include "wdog.h"



struct cdev *cdev_siswdog;


void siswdog_stimeout(int devno, int preferred_timeout)
{
	DebugPrint("[WDOG] setting timeout for wdog[%d] \n", devno);
	if((devno < 1) || (devno > 2)){
		DebugPrint("[WDOG] Error -- There's NO WAY to set wdog[%d] timeout !! \n", devno);
		return;
	}
	if(devno == 1){
#if 0
		__u32 temp = readl((__u32 *)WDT1_Ctl_Reg) & 0xe0000000;
		DebugPrint("[WDOG] setting timeout for wdog[%d] : %d us \n", devno, preferred_timeout);
		writel((preferred_timeout & 0x1fffffff), (__u32 *)WDT1_Ctl_Reg);
		writel(temp | (preferred_timeout & 0x1fffffff), (__u32 *)WDT1_Ctl_Reg);
#endif
	} else if(devno == 2){
		__u32 temp = readl((__u32 *)WDT2_Ctl_Reg) & 0xe0000000;
		DebugPrint("[WDOG] setting timeout for wdog[%d] : %d ms \n", devno, preferred_timeout);
		writel((preferred_timeout & 0x1fffffff), (__u32 *)WDT2_Ctl_Reg);
		writel(temp | (preferred_timeout & 0x1fffffff), (__u32 *)WDT2_Ctl_Reg);
	}
}

void siswdog_keepalive(int devno)
{
		if(devno == 0){
			set_bit(WDT0_Refresh_bit, (void *)(WDT0_Ctl_Reg));
		} else if(devno == 1){
			set_bit(WDT1_Refresh_bit, (void *)(WDT0_Ctl_Reg));
		} else if(devno == 2){
			set_bit(WDT2_Refresh_bit, (void *)(WDT0_Ctl_Reg));
		}
}

EXPORT_SYMBOL(siswdog_keepalive);
#if 1
void siswdog_remove(int devno)
{
	// keep-alive the Watch Dog here for the critical case
	siswdog_keepalive(devno);

		if(devno == 0){
			set_bit(WDT0_Disable_bit, (void *)(WDT0_Ctl_Reg));
		} else if(devno == 1){
			clear_bit(WDT1_Eisable_bit, (void *)(WDT1_Ctl_Reg));
		} else if(devno == 2){
			clear_bit(WDT2_Eisable_bit, (void *)(WDT2_Ctl_Reg));
		} else if(devno == 3){
			//writel(0, (__u32 *)0xbe0f030c);	// clear the Watch Dog 3
		}
}

EXPORT_SYMBOL(siswdog_remove);
#endif
void siswdog_add(int devno, int preferred_timeout)
{
	siswdog_stimeout(devno, preferred_timeout);
    // enable the Watch Dog
	if(devno == 0){
		clear_bit(WDT0_Disable_bit, (void *)(WDT0_Ctl_Reg));
	} else if(devno == 1){
		set_bit(WDT1_Eisable_bit, (void *)(WDT1_Ctl_Reg));
	} else if(devno == 2){
		set_bit(WDT2_Eisable_bit, (void *)(WDT2_Ctl_Reg));
	}
#if 0
	else if(devno == 3){
		writel(SISWDOG3_WarmReset, (__u32 *)WDT3_Ctl_Reg);	// set the Watch Dog 3 to "Warm Reset" at once
	} else if(devno == 4){
		writel(SISWDOG3_ColdReset, (__u32 *)WDT3_Ctl_Reg);	// set the Watch Dog 3 to "Cold Reset" at once
	} else if(devno == 5){
		writel(SISWDOG3_RTCReset, (__u32 *)WDT3_Ctl_Reg);	// set the Watch Dog 3 to "RTC Reset" at once
	}
#endif
	// keep-alive the Watch Dog here for the critical case
	siswdog_keepalive(devno);

}

EXPORT_SYMBOL(siswdog_add);

#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,0,8)
long siswdog_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
#else
ssize_t siswdog_ioctl(struct inode *inode,struct file *filp,unsigned int cmd,unsigned long arg)
#endif
{
	siswdog_ioctl_data parameter;
    switch(cmd){
		case SISWDOG_ADD:
			copy_from_user(&parameter, (void *)arg, sizeof(siswdog_ioctl_data));
			siswdog_add(parameter.devno, parameter.preferred_timeout);
            break;
#if 1
		case SISWDOG_REMOVE:
			siswdog_remove(arg);
			break;
#endif
		case SISWDOG_KEEPALIVE:
            siswdog_keepalive(arg);
			break;

        default:
            break;
    }
	return 0;
}



struct file_operations siswdog_fops = {
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,0,8))
	.unlocked_ioctl = siswdog_ioctl,
#else
	.ioctl = siswdog_ioctl,
#endif
	
	.owner = THIS_MODULE,
};

int siswdog_init(void){
    int ret = 0;
	int devno = MKDEV(SISWDOG_DEV_MAJOR, 130);
	cdev_siswdog = cdev_alloc();
	cdev_siswdog->owner = THIS_MODULE;
	cdev_siswdog->ops = &siswdog_fops;
    ret = cdev_add(cdev_siswdog, devno, 1);
    if (ret)
    {
        printk("\n====[%s, %d], init fail!!! err = %d\n",__FUNCTION__,__LINE__, ret);
		return -EIO;
    }
	*(volatile unsigned int *)(WDT1_Ctl_Reg) = (*(volatile unsigned int *)(WDT1_Ctl_Reg) & ~(0x3 << 29)) | SISWDOG_ColdReset;
	*(volatile unsigned int *)(WDT2_Ctl_Reg) = (*(volatile unsigned int *)(WDT2_Ctl_Reg) & ~(0x3 << 29)) | SISWDOG_ColdReset;

	return 0;
}
#if 0
void siswdog_exit(void){
	cdev_del(cdev_siswdog);
}
#endif
#ifndef INIT_BY_KMF
module_init(siswdog_init);
module_exit(siswdog_exit);
#endif



MODULE_LICENSE("Dual BSD/GPL");