/* * Real Time Clock interface for Samsung S3C2410 MPU * * Based on linux/drivers/char/s3c2400-rtc.c * * Copyright (C) 2003 MIZI Research, Inc. * * Author: Chan Gyun Jeong <cgjeong@mizi.com> * $Id: s3c2410-rtc.c,v 1.1.2.1 2003/01/13 14:52:07 tolkien Exp $ * */#include <linux/config.h>#include <linux/module.h>#include <linux/kernel.h>#include <linux/init.h>#include <linux/miscdevice.h>#include <linux/proc_fs.h>#include <linux/poll.h>#include <linux/rtc.h>#include <asm/hardware.h>#include <asm/uaccess.h>#include <asm/irq.h>#define DRIVER_VERSION		"0.1"#ifndef BCD_TO_BIN#define BCD_TO_BIN(val)		((val)=((val)&15) + ((val)>>4)*10)#endif#ifndef BIN_TO_BCD#define BIN_TO_BCD(val)		((val)=(((val)/10)<<4) + (val)%10)#endif#define RTC_LEAP_YEAR		2000/* Those are the bits from a classic RTC we want to mimic */#ifndef RTC_IRQF#define RTC_IRQF		0x80	/* any of the following 3 is active */#endif#ifndef RTC_PF#define RTC_PF			0x40#endif#ifndef RTC_AF#define RTC_AF			0x20#endif#ifndef RTC_UF#define RTC_UF			0x10#endifstatic unsigned long rtc_status;static unsigned long rtc_irq_data;static struct fasync_struct *rtc_async_queue;static DECLARE_WAIT_QUEUE_HEAD(rtc_wait);extern spinlock_t rtc_lock;static void get_rtc_time(int alm, struct rtc_time *rtc_tm){	spin_lock_irq(&rtc_lock);	if (alm == 1) {		rtc_tm->tm_year = (unsigned char)ALMYEAR & Msk_RTCYEAR;		rtc_tm->tm_mon = (unsigned char)ALMMON & Msk_RTCMON;		rtc_tm->tm_mday = (unsigned char)ALMDAY & Msk_RTCDAY;		rtc_tm->tm_hour = (unsigned char)ALMHOUR & Msk_RTCHOUR;		rtc_tm->tm_min = (unsigned char)ALMMIN & Msk_RTCMIN;		rtc_tm->tm_sec = (unsigned char)ALMSEC & Msk_RTCSEC;	}	else { read_rtc_bcd_time:		rtc_tm->tm_year = (unsigned char)BCDYEAR & Msk_RTCYEAR;		rtc_tm->tm_mon = (unsigned char)BCDMON & Msk_RTCMON;		rtc_tm->tm_mday = (unsigned char)BCDDAY & Msk_RTCDAY;		rtc_tm->tm_hour = (unsigned char)BCDHOUR & Msk_RTCHOUR;		rtc_tm->tm_min = (unsigned char)BCDMIN & Msk_RTCMIN;		rtc_tm->tm_sec = (unsigned char)BCDSEC & Msk_RTCSEC;		if (rtc_tm->tm_sec == 0) {			/* Re-read all BCD registers in case of BCDSEC is 0.			   See RTC section at the manual for more info. */			goto read_rtc_bcd_time;		}	}	spin_unlock_irq(&rtc_lock);	BCD_TO_BIN(rtc_tm->tm_year);	BCD_TO_BIN(rtc_tm->tm_mon);	BCD_TO_BIN(rtc_tm->tm_mday);	BCD_TO_BIN(rtc_tm->tm_hour);	BCD_TO_BIN(rtc_tm->tm_min);	BCD_TO_BIN(rtc_tm->tm_sec);	/* The epoch of tm_year is 1900 */	rtc_tm->tm_year += RTC_LEAP_YEAR - 1900;	/* tm_mon starts at 0, but rtc month starts at 1 */	rtc_tm->tm_mon--;}static int set_rtc_time(int alm, struct rtc_time *rtc_tm){	unsigned char year, mon, day, hour, min, sec;	if (rtc_tm->tm_year < (RTC_LEAP_YEAR - 1900)) {		/* The year must be higher or equal than 2000 */		return -EINVAL;	}	year = (rtc_tm->tm_year + 1900) - RTC_LEAP_YEAR;	mon = rtc_tm->tm_mon + 1; /* tm_mon starts at zero */	day = rtc_tm->tm_mday;	hour = rtc_tm->tm_hour;	min = rtc_tm->tm_min;	sec = rtc_tm->tm_sec;	BIN_TO_BCD(sec);	BIN_TO_BCD(min);	BIN_TO_BCD(hour);	BIN_TO_BCD(day);	BIN_TO_BCD(mon);	BIN_TO_BCD(year);	spin_lock_irq(&rtc_lock); 	/* Enable RTC control */	RTCCON |= RTCCON_EN; 	if (alm) {		ALMSEC = sec & Msk_RTCSEC;		ALMMIN = min & Msk_RTCMIN;		ALMHOUR = hour & Msk_RTCHOUR;		ALMDAY = day & Msk_RTCDAY;		ALMMON = mon & Msk_RTCMON;		ALMYEAR = year & Msk_RTCYEAR;	} 	else {		BCDSEC = sec & Msk_RTCSEC;		BCDMIN = min & Msk_RTCMIN;		BCDHOUR = hour & Msk_RTCHOUR;		BCDDAY = day & Msk_RTCDAY;		BCDMON = mon & Msk_RTCMON;		BCDYEAR = year & Msk_RTCYEAR;	}	/* Disable RTC control */	RTCCON &= ~RTCCON_EN;	spin_unlock_irq(&rtc_lock);	return 0;}static void rtc_alm_interrupt(int irq, void *dev_id, struct pt_regs *regs){	spin_lock (&rtc_lock);	/* Update IRQ data & counter */	rtc_irq_data += 0x100;	rtc_irq_data |= (RTC_AF|RTC_IRQF);	spin_unlock (&rtc_lock);	/* Now do the rest of the actions */	wake_up_interruptible(&rtc_wait);		kill_fasync (&rtc_async_queue, SIGIO, POLL_IN);}static int rtc_open(struct inode *inode, struct file *file){	MOD_INC_USE_COUNT;	spin_lock_irq(&rtc_lock);	if (rtc_status) {		spin_unlock_irq(&rtc_lock);		MOD_DEC_USE_COUNT;		return -EBUSY;	}	rtc_status = 1;	rtc_irq_data = 0;	spin_unlock_irq(&rtc_lock);	return 0;}static int rtc_release(struct inode *inode, struct file *file){	/*	 * Turn off all interrupts once the device is no longer	 * in use, and clear the data.	 */	spin_lock_irq(&rtc_lock);#ifndef CONFIG_MIZI	/* Disable alarm interrupt */	RTCCON |= RTCCON_EN;	RTCALM = RTCALM_DIS;	RTCCON &= ~RTCCON_EN;#endif	rtc_status = 0;	rtc_irq_data = 0;	spin_unlock_irq(&rtc_lock);	MOD_DEC_USE_COUNT;	return 0;}static int rtc_fasync (int fd, struct file *filp, int on){	return fasync_helper (fd, filp, on, &rtc_async_queue);}static unsigned int rtc_poll(struct file *file, poll_table *wait){	unsigned long l;	poll_wait (file, &rtc_wait, wait);	spin_lock_irq (&rtc_lock);	l = rtc_irq_data;	spin_unlock_irq (&rtc_lock);	if (l != 0) { 		return POLLIN | POLLRDNORM;	}	return 0;}ssize_t rtc_read(struct file *file, char *buf, size_t count, loff_t *ppos){	DECLARE_WAITQUEUE(wait, current);	unsigned long data;	ssize_t retval;	if (count < sizeof(unsigned long))		return -EINVAL;	add_wait_queue(&rtc_wait, &wait);	set_current_state(TASK_INTERRUPTIBLE);	while (1) {		spin_lock_irq (&rtc_lock);		data = rtc_irq_data;		rtc_irq_data = 0;		spin_unlock_irq (&rtc_lock);		if (data != 0) {			break;		}				if (file->f_flags & O_NONBLOCK) {			retval = -EAGAIN;			goto out;		}		if (signal_pending(current)) {			retval = -ERESTARTSYS;			goto out;		}		schedule();	}	retval = put_user(data, (unsigned long *)buf);	if (!retval)		retval = sizeof(unsigned long);out:	set_current_state(TASK_RUNNING);	remove_wait_queue(&rtc_wait, &wait);	return retval;}static int rtc_ioctl(struct inode *inode, struct file *file,		     unsigned int cmd, unsigned long arg){	struct rtc_time tm;	switch (cmd) {		/* Alarm interrupt on/off */	case RTC_AIE_ON:		spin_lock_irq (&rtc_lock);		RTCCON |= RTCCON_EN; 		RTCALM = RTCALM_EN; 		RTCCON &= ~RTCCON_EN;		spin_unlock_irq (&rtc_lock);		return 0;	case RTC_AIE_OFF:		spin_lock_irq (&rtc_lock);		RTCCON |= RTCCON_EN;		RTCALM = RTCALM_DIS;		RTCCON &= ~RTCCON_EN;		spin_unlock_irq (&rtc_lock);		return 0;		/* Update interrupt on/off */	case RTC_UIE_ON:	case RTC_UIE_OFF:		/* Periodic interrupt on/off */	case RTC_PIE_ON:	case RTC_PIE_OFF:				case RTC_WIE_ON:	case RTC_WIE_OFF:		/* Periodic interrupt freq get/set */	case RTC_IRQP_READ:	case RTC_IRQP_SET:		/* Epoch get/set */	case RTC_EPOCH_READ:	case RTC_EPOCH_SET:	case RTC_WKALM_SET:	case RTC_WKALM_RD:		/* Not supported */		return -EINVAL;		/* Alarm get/set */	case RTC_ALM_READ:		get_rtc_time(1, &tm);		return copy_to_user((void *)arg, &tm, sizeof(tm)) ? 			-EFAULT : 0;	case RTC_ALM_SET:		if (copy_from_user(&tm, (struct rtc_time*) arg, sizeof(tm))) {			return -EFAULT;		}		return set_rtc_time(1, &tm);		/* Time get/set */	case RTC_RD_TIME:		get_rtc_time(0, &tm);		return copy_to_user((void *)arg, &tm, sizeof(tm)) ? 			-EFAULT : 0;	case RTC_SET_TIME:		if (copy_from_user(&tm, (struct rtc_time*) arg, sizeof(tm))) {			return -EFAULT;		}		return set_rtc_time(0, &tm);	default:		return -EINVAL;	}}#ifdef CONFIG_PROC_FSstatic int rtc_read_proc(char *page, char **start, off_t off,                         int count, int *eof, void *data){	char *p = page;	int len;	struct rtc_time tm;	get_rtc_time(0, &tm);	p += sprintf(p, "rtc_time\t: %02d:%02d:%02d\n"		     "rtc_date\t: %04d-%02d-%02d\n"		     "rtc_epoch\t: %04d\n",		     tm.tm_hour, tm.tm_min, tm.tm_sec,		     tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 		     RTC_LEAP_YEAR);	get_rtc_time(1, &tm);	p += sprintf(p, "alarm_time\t: %02d:%02d:%02d\n"		     "alarm_date\t: %04d-%02d-%02d\n",		     tm.tm_hour, tm.tm_min, tm.tm_sec,		     tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);	p += sprintf(p, "alarm_IRQ\t: %s\n", 		     (RTCALM & RTCALM_EN) ? "yes" : "no" );	len = (p - page) - off;	if (len < 0)		len = 0;	*eof = (len <= count) ? 1 : 0;	*start = page + off;	return len;}#endifstatic struct file_operations rtc_fops = {	owner:		THIS_MODULE,	llseek:		no_llseek,	read:		rtc_read,	poll:		rtc_poll,	ioctl:		rtc_ioctl,	open:		rtc_open,	release:	rtc_release,	fasync:		rtc_fasync,};static struct miscdevice rtc_dev={	RTC_MINOR,	"rtc",	&rtc_fops};static int __init rtc_init(void){	int ret;	misc_register(&rtc_dev);#ifdef CONFIG_PROC_FS	create_proc_read_entry("driver/rtc", 0, 0, rtc_read_proc, NULL);#endif	ret = request_irq(IRQ_RTC, rtc_alm_interrupt, SA_INTERRUPT, 			  "RTC Alarm", NULL);	if (ret) {		printk("s3c2410-rtc: failed to register IRQ_RTC(%d)\n", 		       IRQ_RTC);		goto IRQ_RTC_failed;	}	printk("S3C2410 Real Time Clock Driver v" DRIVER_VERSION "\n");	return 0;IRQ_RTC_failed:#ifdef CONFIG_PROC_FS	remove_proc_entry("driver/rtc", NULL);#endif	misc_deregister(&rtc_dev);	return ret;}static void __exit rtc_exit(void){	free_irq(IRQ_RTC, NULL);#ifdef CONFIG_PROC_FS	remove_proc_entry("driver/rtc", NULL);#endif	misc_deregister(&rtc_dev);}module_init(rtc_init);module_exit(rtc_exit);MODULE_AUTHOR("Chan Gyun Jeong <cgjeong@mizi.com>");MODULE_LICENSE("GPL");MODULE_DESCRIPTION("Real Time Clock interface for Samsung S3C2410 MPU");EXPORT_NO_SYMBOLS;