#include <linux/module.h>#include <rtl_fifo.h>#include <asm/rt_irq.h>#include <linux/rt_time.h>#include <linux/mc146818rtc.h>#include <linux/cons.h>static int filter(int x){	static int oldx;	int ret;	if (x & 0x80) {		x = 382 - x;	}	ret = x > oldx;	oldx = x;	return ret;	}void intr_handler(void) {	char data;	char temp; 	(void) CMOS_READ(RTC_REG_C);        /* clear IRQ */ 	if (rtf_get(0, &data, 1) > 0) {		data = filter(data);/* 		if (data) conpr("1"); else conpr("0"); */		temp = inb(0x61);            		temp &= 0xfc;		if (data) {			temp |= 3;		}		outb(temp,0x61);	}}char save_cmos_A;char save_cmos_B;int init_module(void){	char ctemp;	if (!I8253_channel2_free()) {		conpr("RTLinux sound: can't use channel 2; bailing out\n");		return -1;	}	rtf_create(0, 4000);	/* this is just to ensure that the output of the counter is 1 */	outb_p(0xb0, 0x43);	/* binary, mode 0, LSB/MSB, ch 2 */	outb_p(0x1, 0x42);	outb_p(0x0, 0x42);	request_RTirq(8, intr_handler);	/* program the RTC to interrupt at 8192 Hz */	save_cmos_A = CMOS_READ(RTC_REG_A);	save_cmos_B = CMOS_READ(RTC_REG_B);	CMOS_WRITE(0x23, RTC_REG_A);  	/* 32kHz Time Base, 8192 Hz interrupt frequency */	ctemp = CMOS_READ(RTC_REG_B);	ctemp &= 0x8f;                	/* Clear */	ctemp |= 0x40;                	/* Periodic interrupt enable */	CMOS_WRITE(ctemp, RTC_REG_B); 	(void) CMOS_READ(RTC_REG_C);	return 0;} void cleanup_module(void){	rtf_destroy(0);	outb_p(0xb6, 0x43);	/* restore the original mode */	CMOS_WRITE(save_cmos_A, RTC_REG_A);	CMOS_WRITE(save_cmos_B, RTC_REG_B);	free_RTirq(8);}