[mirror_ubuntu-bionic-kernel.git] / drivers / char / vr41xx_rtc.c

/*
 *  Driver for NEC VR4100 series  Real Time Clock unit.
 *
 *  Copyright (C) 2003-2005  Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include <linux/platform_device.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/mc146818rtc.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/poll.h>
#include <linux/rtc.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <linux/wait.h>

#include <asm/div64.h>
#include <asm/io.h>
#include <asm/time.h>
#include <asm/uaccess.h>
#include <asm/vr41xx/vr41xx.h>

MODULE_AUTHOR("Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>");
MODULE_DESCRIPTION("NEC VR4100 series RTC driver");
MODULE_LICENSE("GPL");

#define RTC1_TYPE1_START	0x0b0000c0UL
#define RTC1_TYPE1_END		0x0b0000dfUL
#define RTC2_TYPE1_START	0x0b0001c0UL
#define RTC2_TYPE1_END		0x0b0001dfUL

#define RTC1_TYPE2_START	0x0f000100UL
#define RTC1_TYPE2_END		0x0f00011fUL
#define RTC2_TYPE2_START	0x0f000120UL
#define RTC2_TYPE2_END		0x0f00013fUL

#define RTC1_SIZE		0x20
#define RTC2_SIZE		0x20

/* RTC 1 registers */
#define ETIMELREG		0x00
#define ETIMEMREG		0x02
#define ETIMEHREG		0x04
/* RFU */
#define ECMPLREG		0x08
#define ECMPMREG		0x0a
#define ECMPHREG		0x0c
/* RFU */
#define RTCL1LREG		0x10
#define RTCL1HREG		0x12
#define RTCL1CNTLREG		0x14
#define RTCL1CNTHREG		0x16
#define RTCL2LREG		0x18
#define RTCL2HREG		0x1a
#define RTCL2CNTLREG		0x1c
#define RTCL2CNTHREG		0x1e

/* RTC 2 registers */
#define TCLKLREG		0x00
#define TCLKHREG		0x02
#define TCLKCNTLREG		0x04
#define TCLKCNTHREG		0x06
/* RFU */
#define RTCINTREG		0x1e
 #define TCLOCK_INT		0x08
 #define RTCLONG2_INT		0x04
 #define RTCLONG1_INT		0x02
 #define ELAPSEDTIME_INT	0x01

#define RTC_FREQUENCY		32768
#define MAX_PERIODIC_RATE	6553
#define MAX_USER_PERIODIC_RATE	64

static void __iomem *rtc1_base;
static void __iomem *rtc2_base;

#define rtc1_read(offset)		readw(rtc1_base + (offset))
#define rtc1_write(offset, value)	writew((value), rtc1_base + (offset))

#define rtc2_read(offset)		readw(rtc2_base + (offset))
#define rtc2_write(offset, value)	writew((value), rtc2_base + (offset))

static unsigned long epoch = 1970;	/* Jan 1 1970 00:00:00 */

static spinlock_t rtc_task_lock;
static wait_queue_head_t rtc_wait;
static unsigned long rtc_irq_data;
static struct fasync_struct *rtc_async_queue;
static rtc_task_t *rtc_callback;
static char rtc_name[] = "RTC";
static unsigned long periodic_frequency;
static unsigned long periodic_count;

typedef enum {
	RTC_RELEASE,
	RTC_OPEN,
} rtc_status_t;

static rtc_status_t rtc_status;

typedef enum {
	FUNCTION_RTC_IOCTL,
	FUNCTION_RTC_CONTROL,
} rtc_callfrom_t;

struct resource rtc_resource[2] = {
	{	.name	= rtc_name,
		.flags	= IORESOURCE_MEM,	},
	{	.name	= rtc_name,
		.flags	= IORESOURCE_MEM,	},
};

static inline unsigned long read_elapsed_second(void)
{
	unsigned long first_low, first_mid, first_high;
	unsigned long second_low, second_mid, second_high;

	do {
		first_low = rtc1_read(ETIMELREG);
		first_mid = rtc1_read(ETIMEMREG);
		first_high = rtc1_read(ETIMEHREG);
		second_low = rtc1_read(ETIMELREG);
		second_mid = rtc1_read(ETIMEMREG);
		second_high = rtc1_read(ETIMEHREG);
	} while (first_low != second_low || first_mid != second_mid ||
	         first_high != second_high);

	return (first_high << 17) | (first_mid << 1) | (first_low >> 15);
}

static inline void write_elapsed_second(unsigned long sec)
{
	spin_lock_irq(&rtc_lock);

	rtc1_write(ETIMELREG, (uint16_t)(sec << 15));
	rtc1_write(ETIMEMREG, (uint16_t)(sec >> 1));
	rtc1_write(ETIMEHREG, (uint16_t)(sec >> 17));

	spin_unlock_irq(&rtc_lock);
}

static void set_alarm(struct rtc_time *time)
{
	unsigned long alarm_sec;

	alarm_sec = mktime(time->tm_year + 1900, time->tm_mon + 1, time->tm_mday,
	                   time->tm_hour, time->tm_min, time->tm_sec);

	spin_lock_irq(&rtc_lock);

	rtc1_write(ECMPLREG, (uint16_t)(alarm_sec << 15));
	rtc1_write(ECMPMREG, (uint16_t)(alarm_sec >> 1));
	rtc1_write(ECMPHREG, (uint16_t)(alarm_sec >> 17));

	spin_unlock_irq(&rtc_lock);
}

static void read_alarm(struct rtc_time *time)
{
	unsigned long low, mid, high;

	spin_lock_irq(&rtc_lock);

	low = rtc1_read(ECMPLREG);
	mid = rtc1_read(ECMPMREG);
	high = rtc1_read(ECMPHREG);

	spin_unlock_irq(&rtc_lock);

	to_tm((high << 17) | (mid << 1) | (low >> 15), time);
	time->tm_year -= 1900;
}

static void read_time(struct rtc_time *time)
{
	unsigned long epoch_sec, elapsed_sec;

	epoch_sec = mktime(epoch, 1, 1, 0, 0, 0);
	elapsed_sec = read_elapsed_second();

	to_tm(epoch_sec + elapsed_sec, time);
	time->tm_year -= 1900;
}

static void set_time(struct rtc_time *time)
{
	unsigned long epoch_sec, current_sec;

	epoch_sec = mktime(epoch, 1, 1, 0, 0, 0);
	current_sec = mktime(time->tm_year + 1900, time->tm_mon + 1, time->tm_mday,
	                     time->tm_hour, time->tm_min, time->tm_sec);

	write_elapsed_second(current_sec - epoch_sec);
}

static ssize_t rtc_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
{
	DECLARE_WAITQUEUE(wait, current);
	unsigned long irq_data;
	int retval = 0;

	if (count != sizeof(unsigned int) && count != sizeof(unsigned long))
		return -EINVAL;

	add_wait_queue(&rtc_wait, &wait);

	do {
		__set_current_state(TASK_INTERRUPTIBLE);

		spin_lock_irq(&rtc_lock);
		irq_data = rtc_irq_data;
		rtc_irq_data = 0;
		spin_unlock_irq(&rtc_lock);

		if (irq_data != 0)
			break;

		if (file->f_flags & O_NONBLOCK) {
			retval = -EAGAIN;
			break;
		}

		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
	} while (1);

	if (retval == 0) {
		if (count == sizeof(unsigned int)) {
			retval = put_user(irq_data, (unsigned int __user *)buf);
			if (retval == 0)
				retval = sizeof(unsigned int);
		} else {
			retval = put_user(irq_data, (unsigned long __user *)buf);
			if (retval == 0)
				retval = sizeof(unsigned long);
		}

	}

	__set_current_state(TASK_RUNNING);
	remove_wait_queue(&rtc_wait, &wait);

	return retval;
}

static unsigned int rtc_poll(struct file *file, struct poll_table_struct *table)
{
	poll_wait(file, &rtc_wait, table);

	if (rtc_irq_data != 0)
		return POLLIN | POLLRDNORM;

	return 0;
}

static int rtc_do_ioctl(unsigned int cmd, unsigned long arg, rtc_callfrom_t from)
{
	struct rtc_time time;
	unsigned long count;

	switch (cmd) {
	case RTC_AIE_ON:
		enable_irq(ELAPSEDTIME_IRQ);
		break;
	case RTC_AIE_OFF:
		disable_irq(ELAPSEDTIME_IRQ);
		break;
	case RTC_PIE_ON:
		enable_irq(RTCLONG1_IRQ);
		break;
	case RTC_PIE_OFF:
		disable_irq(RTCLONG1_IRQ);
		break;
	case RTC_ALM_SET:
		if (copy_from_user(&time, (struct rtc_time __user *)arg,
		                   sizeof(struct rtc_time)))
			return -EFAULT;

		set_alarm(&time);
		break;
	case RTC_ALM_READ:
		memset(&time, 0, sizeof(struct rtc_time));
		read_alarm(&time);
		break;
	case RTC_RD_TIME:
		memset(&time, 0, sizeof(struct rtc_time));
		read_time(&time);
		if (copy_to_user((void __user *)arg, &time, sizeof(struct rtc_time)))
			return -EFAULT;
		break;
	case RTC_SET_TIME:
		if (capable(CAP_SYS_TIME) == 0)
			return -EACCES;

		if (copy_from_user(&time, (struct rtc_time __user *)arg,
		                   sizeof(struct rtc_time)))
			return -EFAULT;

		set_time(&time);
		break;
	case RTC_IRQP_READ:
		return put_user(periodic_frequency, (unsigned long __user *)arg);
		break;
	case RTC_IRQP_SET:
		if (arg > MAX_PERIODIC_RATE)
			return -EINVAL;

		if (from == FUNCTION_RTC_IOCTL && arg > MAX_USER_PERIODIC_RATE &&
		    capable(CAP_SYS_RESOURCE) == 0)
			return -EACCES;

		periodic_frequency = arg;

		count = RTC_FREQUENCY;
		do_div(count, arg);

		periodic_count = count;

		spin_lock_irq(&rtc_lock);

		rtc1_write(RTCL1LREG, count);
		rtc1_write(RTCL1HREG, count >> 16);

		spin_unlock_irq(&rtc_lock);
		break;
	case RTC_EPOCH_READ:
		return put_user(epoch, (unsigned long __user *)arg);
	case RTC_EPOCH_SET:
		/* Doesn't support before 1900 */
		if (arg < 1900)
			return -EINVAL;

		if (capable(CAP_SYS_TIME) == 0)
			return -EACCES;

		epoch = arg;
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
                     unsigned long arg)
{
	return rtc_do_ioctl(cmd, arg, FUNCTION_RTC_IOCTL);
}

static int rtc_open(struct inode *inode, struct file *file)
{
	spin_lock_irq(&rtc_lock);

	if (rtc_status == RTC_OPEN) {
		spin_unlock_irq(&rtc_lock);
		return -EBUSY;
	}

	rtc_status = RTC_OPEN;
	rtc_irq_data = 0;

	spin_unlock_irq(&rtc_lock);

	return 0;
}

static int rtc_release(struct inode *inode, struct file *file)
{
	if (file->f_flags & FASYNC)
		(void)fasync_helper(-1, file, 0, &rtc_async_queue);

	spin_lock_irq(&rtc_lock);

	rtc1_write(ECMPLREG, 0);
	rtc1_write(ECMPMREG, 0);
	rtc1_write(ECMPHREG, 0);
	rtc1_write(RTCL1LREG, 0);
	rtc1_write(RTCL1HREG, 0);

	rtc_status = RTC_RELEASE;

	spin_unlock_irq(&rtc_lock);

	disable_irq(ELAPSEDTIME_IRQ);
	disable_irq(RTCLONG1_IRQ);

	return 0;
}

static int rtc_fasync(int fd, struct file *file, int on)
{
	return fasync_helper(fd, file, on, &rtc_async_queue);
}

static 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 irqreturn_t elapsedtime_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	spin_lock(&rtc_lock);
	rtc2_write(RTCINTREG, ELAPSEDTIME_INT);

	rtc_irq_data += 0x100;
	rtc_irq_data &= ~0xff;
	rtc_irq_data |= RTC_AF;
	spin_unlock(&rtc_lock);

	spin_lock(&rtc_lock);
	if (rtc_callback)
		rtc_callback->func(rtc_callback->private_data);
	spin_unlock(&rtc_lock);

	wake_up_interruptible(&rtc_wait);

	kill_fasync(&rtc_async_queue, SIGIO, POLL_IN);

	return IRQ_HANDLED;
}

static irqreturn_t rtclong1_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	unsigned long count = periodic_count;

	spin_lock(&rtc_lock);
	rtc2_write(RTCINTREG, RTCLONG1_INT);

	rtc1_write(RTCL1LREG, count);
	rtc1_write(RTCL1HREG, count >> 16);

	rtc_irq_data += 0x100;
	rtc_irq_data &= ~0xff;
	rtc_irq_data |= RTC_PF;
	spin_unlock(&rtc_lock);

	spin_lock(&rtc_task_lock);
	if (rtc_callback)
		rtc_callback->func(rtc_callback->private_data);
	spin_unlock(&rtc_task_lock);

	wake_up_interruptible(&rtc_wait);

	kill_fasync(&rtc_async_queue, SIGIO, POLL_IN);

	return IRQ_HANDLED;
}

int rtc_register(rtc_task_t *task)
{
	if (task == NULL || task->func == NULL)
		return -EINVAL;

	spin_lock_irq(&rtc_lock);
	if (rtc_status == RTC_OPEN) {
		spin_unlock_irq(&rtc_lock);
		return -EBUSY;
	}

	spin_lock(&rtc_task_lock);
	if (rtc_callback != NULL) {
		spin_unlock(&rtc_task_lock);
		spin_unlock_irq(&rtc_task_lock);
		return -EBUSY;
	}

	rtc_callback = task;
	spin_unlock(&rtc_task_lock);

	rtc_status = RTC_OPEN;

	spin_unlock_irq(&rtc_lock);

	return 0;
}

EXPORT_SYMBOL_GPL(rtc_register);

int rtc_unregister(rtc_task_t *task)
{
	spin_lock_irq(&rtc_task_lock);
	if (task == NULL || rtc_callback != task) {
		spin_unlock_irq(&rtc_task_lock);
		return -ENXIO;
	}

	spin_lock(&rtc_lock);

	rtc1_write(ECMPLREG, 0);
	rtc1_write(ECMPMREG, 0);
	rtc1_write(ECMPHREG, 0);
	rtc1_write(RTCL1LREG, 0);
	rtc1_write(RTCL1HREG, 0);

	rtc_status = RTC_RELEASE;

	spin_unlock(&rtc_lock);

	rtc_callback = NULL;

	spin_unlock_irq(&rtc_task_lock);

	disable_irq(ELAPSEDTIME_IRQ);
	disable_irq(RTCLONG1_IRQ);

	return 0;
}

EXPORT_SYMBOL_GPL(rtc_unregister);

int rtc_control(rtc_task_t *task, unsigned int cmd, unsigned long arg)
{
	int retval = 0;

	spin_lock_irq(&rtc_task_lock);

	if (rtc_callback != task)
		retval = -ENXIO;
	else
		rtc_do_ioctl(cmd, arg, FUNCTION_RTC_CONTROL);

	spin_unlock_irq(&rtc_task_lock);

	return retval;
}

EXPORT_SYMBOL_GPL(rtc_control);

static struct miscdevice rtc_miscdevice = {
	.minor	= RTC_MINOR,
	.name	= rtc_name,
	.fops	= &rtc_fops,
};

static int __devinit rtc_probe(struct platform_device *pdev)
{
	unsigned int irq;
	int retval;

	if (pdev->num_resources != 2)
		return -EBUSY;

	rtc1_base = ioremap(pdev->resource[0].start, RTC1_SIZE);
	if (rtc1_base == NULL)
		return -EBUSY;

	rtc2_base = ioremap(pdev->resource[1].start, RTC2_SIZE);
	if (rtc2_base == NULL) {
		iounmap(rtc1_base);
		rtc1_base = NULL;
		return -EBUSY;
	}

	retval = misc_register(&rtc_miscdevice);
	if (retval < 0) {
		iounmap(rtc1_base);
		iounmap(rtc2_base);
		rtc1_base = NULL;
		rtc2_base = NULL;
		return retval;
	}

	spin_lock_irq(&rtc_lock);

	rtc1_write(ECMPLREG, 0);
	rtc1_write(ECMPMREG, 0);
	rtc1_write(ECMPHREG, 0);
	rtc1_write(RTCL1LREG, 0);
	rtc1_write(RTCL1HREG, 0);

	rtc_status = RTC_RELEASE;
	rtc_irq_data = 0;

	spin_unlock_irq(&rtc_lock);

	init_waitqueue_head(&rtc_wait);

	irq = ELAPSEDTIME_IRQ;
	retval = request_irq(irq, elapsedtime_interrupt, SA_INTERRUPT,
	                     "elapsed_time", NULL);
	if (retval == 0) {
		irq = RTCLONG1_IRQ;
		retval = request_irq(irq, rtclong1_interrupt, SA_INTERRUPT,
		                     "rtclong1", NULL);
	}

	if (retval < 0) {
		printk(KERN_ERR "rtc: IRQ%d is busy\n", irq);
		if (irq == RTCLONG1_IRQ)
			free_irq(ELAPSEDTIME_IRQ, NULL);
		iounmap(rtc1_base);
		iounmap(rtc2_base);
		rtc1_base = NULL;
		rtc2_base = NULL;
		return retval;
	}

	disable_irq(ELAPSEDTIME_IRQ);
	disable_irq(RTCLONG1_IRQ);

	spin_lock_init(&rtc_task_lock);

	printk(KERN_INFO "rtc: Real Time Clock of NEC VR4100 series\n");

	return 0;
}

static int __devexit rtc_remove(struct platform_device *dev)
{
	int retval;

	retval = misc_deregister(&rtc_miscdevice);
	if (retval < 0)
		return retval;

	free_irq(ELAPSEDTIME_IRQ, NULL);
	free_irq(RTCLONG1_IRQ, NULL);
	if (rtc1_base != NULL)
		iounmap(rtc1_base);
	if (rtc2_base != NULL)
		iounmap(rtc2_base);

	return 0;
}

static struct platform_device *rtc_platform_device;

static struct platform_driver rtc_device_driver = {
	.probe		= rtc_probe,
	.remove		= __devexit_p(rtc_remove),
	.driver		= {
		.name	= rtc_name,
		.owner	= THIS_MODULE,
	},
};

static int __init vr41xx_rtc_init(void)
{
	int retval;

	switch (current_cpu_data.cputype) {
	case CPU_VR4111:
	case CPU_VR4121:
		rtc_resource[0].start = RTC1_TYPE1_START;
		rtc_resource[0].end = RTC1_TYPE1_END;
		rtc_resource[1].start = RTC2_TYPE1_START;
		rtc_resource[1].end = RTC2_TYPE1_END;
		break;
	case CPU_VR4122:
	case CPU_VR4131:
	case CPU_VR4133:
		rtc_resource[0].start = RTC1_TYPE2_START;
		rtc_resource[0].end = RTC1_TYPE2_END;
		rtc_resource[1].start = RTC2_TYPE2_START;
		rtc_resource[1].end = RTC2_TYPE2_END;
		break;
	default:
		return -ENODEV;
		break;
	}

	rtc_platform_device = platform_device_alloc("RTC", -1);
	if (!rtc_platform_device)
		return -ENOMEM;

	retval = platform_device_add_resources(rtc_platform_device,
				rtc_resource, ARRAY_SIZE(rtc_resource));

	if (retval == 0)
		retval = platform_device_add(rtc_platform_device);

	if (retval < 0) {
		platform_device_put(rtc_platform_device);
		return retval;
	}

	retval = platform_driver_register(&rtc_device_driver);
	if (retval < 0)
		platform_device_unregister(rtc_platform_device);

	return retval;
}

static void __exit vr41xx_rtc_exit(void)
{
	platform_driver_unregister(&rtc_device_driver);
	platform_device_unregister(rtc_platform_device);
}

module_init(vr41xx_rtc_init);
module_exit(vr41xx_rtc_exit);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Driver for NEC VR4100 series Real Time Clock unit.
	3	*
29ce2c76	4	* Copyright (C) 2003-2005 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
1da177e4 LT	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	*/
d052d1be	20	#include <linux/platform_device.h>
1da177e4 LT	21	#include <linux/fs.h>
	22	#include <linux/init.h>
	23	#include <linux/ioport.h>
	24	#include <linux/irq.h>
	25	#include <linux/mc146818rtc.h>
	26	#include <linux/miscdevice.h>
	27	#include <linux/module.h>
	28	#include <linux/poll.h>
	29	#include <linux/rtc.h>
	30	#include <linux/spinlock.h>
	31	#include <linux/types.h>
	32	#include <linux/wait.h>
	33
	34	#include <asm/div64.h>
	35	#include <asm/io.h>
	36	#include <asm/time.h>
	37	#include <asm/uaccess.h>
	38	#include <asm/vr41xx/vr41xx.h>
	39
29ce2c76	40	MODULE_AUTHOR("Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>");
1da177e4 LT	41	MODULE_DESCRIPTION("NEC VR4100 series RTC driver");
	42	MODULE_LICENSE("GPL");
	43
	44	#define RTC1_TYPE1_START 0x0b0000c0UL
	45	#define RTC1_TYPE1_END 0x0b0000dfUL
	46	#define RTC2_TYPE1_START 0x0b0001c0UL
	47	#define RTC2_TYPE1_END 0x0b0001dfUL
	48
	49	#define RTC1_TYPE2_START 0x0f000100UL
	50	#define RTC1_TYPE2_END 0x0f00011fUL
	51	#define RTC2_TYPE2_START 0x0f000120UL
	52	#define RTC2_TYPE2_END 0x0f00013fUL
	53
	54	#define RTC1_SIZE 0x20
	55	#define RTC2_SIZE 0x20
	56
	57	/* RTC 1 registers */
	58	#define ETIMELREG 0x00
	59	#define ETIMEMREG 0x02
	60	#define ETIMEHREG 0x04
	61	/* RFU */
	62	#define ECMPLREG 0x08
	63	#define ECMPMREG 0x0a
	64	#define ECMPHREG 0x0c
	65	/* RFU */
	66	#define RTCL1LREG 0x10
	67	#define RTCL1HREG 0x12
	68	#define RTCL1CNTLREG 0x14
	69	#define RTCL1CNTHREG 0x16
	70	#define RTCL2LREG 0x18
	71	#define RTCL2HREG 0x1a
	72	#define RTCL2CNTLREG 0x1c
	73	#define RTCL2CNTHREG 0x1e
	74
	75	/* RTC 2 registers */
	76	#define TCLKLREG 0x00
	77	#define TCLKHREG 0x02
	78	#define TCLKCNTLREG 0x04
	79	#define TCLKCNTHREG 0x06
	80	/* RFU */
	81	#define RTCINTREG 0x1e
	82	#define TCLOCK_INT 0x08
	83	#define RTCLONG2_INT 0x04
	84	#define RTCLONG1_INT 0x02
	85	#define ELAPSEDTIME_INT 0x01
	86
	87	#define RTC_FREQUENCY 32768
	88	#define MAX_PERIODIC_RATE 6553
	89	#define MAX_USER_PERIODIC_RATE 64
	90
	91	static void __iomem *rtc1_base;
	92	static void __iomem *rtc2_base;
	93
	94	#define rtc1_read(offset) readw(rtc1_base + (offset))
	95	#define rtc1_write(offset, value) writew((value), rtc1_base + (offset))
	96
	97	#define rtc2_read(offset) readw(rtc2_base + (offset))
	98	#define rtc2_write(offset, value) writew((value), rtc2_base + (offset))
	99
	100	static unsigned long epoch = 1970; /* Jan 1 1970 00:00:00 */
	101
	102	static spinlock_t rtc_task_lock;
	103	static wait_queue_head_t rtc_wait;
	104	static unsigned long rtc_irq_data;
105	static struct fasync_struct *rtc_async_queue;
106	static rtc_task_t *rtc_callback;
107	static char rtc_name[] = "RTC";
108	static unsigned long periodic_frequency;
109	static unsigned long periodic_count;
110
111	typedef enum {
112	RTC_RELEASE,
113	RTC_OPEN,
114	} rtc_status_t;
115
116	static rtc_status_t rtc_status;
117
118	typedef enum {
119	FUNCTION_RTC_IOCTL,
120	FUNCTION_RTC_CONTROL,
121	} rtc_callfrom_t;
122
123	struct resource rtc_resource[2] = {
124	{ .name = rtc_name,
125	.flags = IORESOURCE_MEM, },
126	{ .name = rtc_name,
127	.flags = IORESOURCE_MEM, },
128	};
129
1da177e4 LT	130	static inline unsigned long read_elapsed_second(void)
	131	{
	132	unsigned long first_low, first_mid, first_high;
	133	unsigned long second_low, second_mid, second_high;
	134
	135	do {
	136	first_low = rtc1_read(ETIMELREG);
	137	first_mid = rtc1_read(ETIMEMREG);
	138	first_high = rtc1_read(ETIMEHREG);
	139	second_low = rtc1_read(ETIMELREG);
	140	second_mid = rtc1_read(ETIMEMREG);
	141	second_high = rtc1_read(ETIMEHREG);
	142	} while (first_low != second_low \|\| first_mid != second_mid \|\|
	143	first_high != second_high);
	144
	145	return (first_high << 17) \| (first_mid << 1) \| (first_low >> 15);
	146	}
	147
	148	static inline void write_elapsed_second(unsigned long sec)
	149	{
	150	spin_lock_irq(&rtc_lock);
	151
	152	rtc1_write(ETIMELREG, (uint16_t)(sec << 15));
	153	rtc1_write(ETIMEMREG, (uint16_t)(sec >> 1));
	154	rtc1_write(ETIMEHREG, (uint16_t)(sec >> 17));
	155
	156	spin_unlock_irq(&rtc_lock);
	157	}
	158
	159	static void set_alarm(struct rtc_time *time)
	160	{
	161	unsigned long alarm_sec;
	162
	163	alarm_sec = mktime(time->tm_year + 1900, time->tm_mon + 1, time->tm_mday,
	164	time->tm_hour, time->tm_min, time->tm_sec);
	165
	166	spin_lock_irq(&rtc_lock);
	167
	168	rtc1_write(ECMPLREG, (uint16_t)(alarm_sec << 15));
	169	rtc1_write(ECMPMREG, (uint16_t)(alarm_sec >> 1));
	170	rtc1_write(ECMPHREG, (uint16_t)(alarm_sec >> 17));
	171
	172	spin_unlock_irq(&rtc_lock);
	173	}
	174
	175	static void read_alarm(struct rtc_time *time)
	176	{
	177	unsigned long low, mid, high;
	178
	179	spin_lock_irq(&rtc_lock);
	180
	181	low = rtc1_read(ECMPLREG);
	182	mid = rtc1_read(ECMPMREG);
	183	high = rtc1_read(ECMPHREG);
	184
	185	spin_unlock_irq(&rtc_lock);
	186
	187	to_tm((high << 17) \| (mid << 1) \| (low >> 15), time);
	188	time->tm_year -= 1900;
	189	}
	190
	191	static void read_time(struct rtc_time *time)
	192	{
	193	unsigned long epoch_sec, elapsed_sec;
194
195	epoch_sec = mktime(epoch, 1, 1, 0, 0, 0);
196	elapsed_sec = read_elapsed_second();
197
198	to_tm(epoch_sec + elapsed_sec, time);
199	time->tm_year -= 1900;
200	}
201
202	static void set_time(struct rtc_time *time)
203	{
204	unsigned long epoch_sec, current_sec;
205
206	epoch_sec = mktime(epoch, 1, 1, 0, 0, 0);
207	current_sec = mktime(time->tm_year + 1900, time->tm_mon + 1, time->tm_mday,
208	time->tm_hour, time->tm_min, time->tm_sec);
209
210	write_elapsed_second(current_sec - epoch_sec);
211	}
212
213	static ssize_t rtc_read(struct file file, char __user buf, size_t count, loff_t *ppos)
214	{
215	DECLARE_WAITQUEUE(wait, current);
216	unsigned long irq_data;
217	int retval = 0;
218
219	if (count != sizeof(unsigned int) && count != sizeof(unsigned long))
220	return -EINVAL;
221
222	add_wait_queue(&rtc_wait, &wait);
223
224	do {
225	__set_current_state(TASK_INTERRUPTIBLE);
226
227	spin_lock_irq(&rtc_lock);
228	irq_data = rtc_irq_data;
229	rtc_irq_data = 0;
230	spin_unlock_irq(&rtc_lock);
231
232	if (irq_data != 0)
233	break;
234
235	if (file->f_flags & O_NONBLOCK) {
236	retval = -EAGAIN;
237	break;
238	}
239
240	if (signal_pending(current)) {
241	retval = -ERESTARTSYS;
242	break;
243	}
244	} while (1);
245
246	if (retval == 0) {
247	if (count == sizeof(unsigned int)) {
248	retval = put_user(irq_data, (unsigned int __user *)buf);
249	if (retval == 0)
250	retval = sizeof(unsigned int);
251	} else {
252	retval = put_user(irq_data, (unsigned long __user *)buf);
253	if (retval == 0)
254	retval = sizeof(unsigned long);
255	}
256
257	}
258
259	__set_current_state(TASK_RUNNING);
260	remove_wait_queue(&rtc_wait, &wait);
261
262	return retval;
263	}
264
265	static unsigned int rtc_poll(struct file file, struct poll_table_struct table)
266	{
267	poll_wait(file, &rtc_wait, table);
268
269	if (rtc_irq_data != 0)
270	return POLLIN \| POLLRDNORM;
271
272	return 0;
273	}
274
275	static int rtc_do_ioctl(unsigned int cmd, unsigned long arg, rtc_callfrom_t from)
276	{
277	struct rtc_time time;
278	unsigned long count;
279
280	switch (cmd) {
281	case RTC_AIE_ON:
282	enable_irq(ELAPSEDTIME_IRQ);
283	break;
284	case RTC_AIE_OFF:
285	disable_irq(ELAPSEDTIME_IRQ);
286	break;
287	case RTC_PIE_ON:
288	enable_irq(RTCLONG1_IRQ);
289	break;
290	case RTC_PIE_OFF:
291	disable_irq(RTCLONG1_IRQ);
292	break;
293	case RTC_ALM_SET:
294	if (copy_from_user(&time, (struct rtc_time __user *)arg,
295	sizeof(struct rtc_time)))
296	return -EFAULT;
297
298	set_alarm(&time);
299	break;
300	case RTC_ALM_READ:
301	memset(&time, 0, sizeof(struct rtc_time));
302	read_alarm(&time);
303	break;
304	case RTC_RD_TIME:
305	memset(&time, 0, sizeof(struct rtc_time));
306	read_time(&time);
307	if (copy_to_user((void __user *)arg, &time, sizeof(struct rtc_time)))
308	return -EFAULT;
309	break;
310	case RTC_SET_TIME:
311	if (capable(CAP_SYS_TIME) == 0)
312	return -EACCES;
313
314	if (copy_from_user(&time, (struct rtc_time __user *)arg,
315	sizeof(struct rtc_time)))
316	return -EFAULT;
317
318	set_time(&time);
319	break;
320	case RTC_IRQP_READ:
321	return put_user(periodic_frequency, (unsigned long __user *)arg);
322	break;
323	case RTC_IRQP_SET:
324	if (arg > MAX_PERIODIC_RATE)
325	return -EINVAL;
326
327	if (from == FUNCTION_RTC_IOCTL && arg > MAX_USER_PERIODIC_RATE &&
328	capable(CAP_SYS_RESOURCE) == 0)
329	return -EACCES;
330
331	periodic_frequency = arg;
332
333	count = RTC_FREQUENCY;
334	do_div(count, arg);
335
336	periodic_count = count;
337
338	spin_lock_irq(&rtc_lock);
339
340	rtc1_write(RTCL1LREG, count);
341	rtc1_write(RTCL1HREG, count >> 16);
342
343	spin_unlock_irq(&rtc_lock);
344	break;
345	case RTC_EPOCH_READ:
346	return put_user(epoch, (unsigned long __user *)arg);
347	case RTC_EPOCH_SET:
348	/* Doesn't support before 1900 */
349	if (arg < 1900)
350	return -EINVAL;
351
352	if (capable(CAP_SYS_TIME) == 0)
353	return -EACCES;
354
355	epoch = arg;
356	break;
357	default:
358	return -EINVAL;
359	}
360
361	return 0;
362	}
363
364	static int rtc_ioctl(struct inode inode, struct file file, unsigned int cmd,
365	unsigned long arg)
366	{
367	return rtc_do_ioctl(cmd, arg, FUNCTION_RTC_IOCTL);
368	}
369
370	static int rtc_open(struct inode inode, struct file file)
371	{
372	spin_lock_irq(&rtc_lock);
373
374	if (rtc_status == RTC_OPEN) {
375	spin_unlock_irq(&rtc_lock);
376	return -EBUSY;
377	}
378
379	rtc_status = RTC_OPEN;
380	rtc_irq_data = 0;
381
382	spin_unlock_irq(&rtc_lock);
383
384	return 0;
385	}
386
387	static int rtc_release(struct inode inode, struct file file)
388	{
389	if (file->f_flags & FASYNC)
390	(void)fasync_helper(-1, file, 0, &rtc_async_queue);
391
392	spin_lock_irq(&rtc_lock);
393
394	rtc1_write(ECMPLREG, 0);
395	rtc1_write(ECMPMREG, 0);
396	rtc1_write(ECMPHREG, 0);
397	rtc1_write(RTCL1LREG, 0);
398	rtc1_write(RTCL1HREG, 0);
399
400	rtc_status = RTC_RELEASE;
401
402	spin_unlock_irq(&rtc_lock);
403
404	disable_irq(ELAPSEDTIME_IRQ);
405	disable_irq(RTCLONG1_IRQ);
406
407	return 0;
408	}
409
410	static int rtc_fasync(int fd, struct file *file, int on)
411	{
412	return fasync_helper(fd, file, on, &rtc_async_queue);
413	}
414
415	static struct file_operations rtc_fops = {
416	.owner = THIS_MODULE,
417	.llseek = no_llseek,
418	.read = rtc_read,
419	.poll = rtc_poll,
420	.ioctl = rtc_ioctl,
421	.open = rtc_open,
422	.release = rtc_release,
423	.fasync = rtc_fasync,
424	};
425
426	static irqreturn_t elapsedtime_interrupt(int irq, void dev_id, struct pt_regs regs)
427	{
428	spin_lock(&rtc_lock);
429	rtc2_write(RTCINTREG, ELAPSEDTIME_INT);
430
431	rtc_irq_data += 0x100;
432	rtc_irq_data &= ~0xff;
433	rtc_irq_data \|= RTC_AF;
434	spin_unlock(&rtc_lock);
435
436	spin_lock(&rtc_lock);
437	if (rtc_callback)
438	rtc_callback->func(rtc_callback->private_data);
439	spin_unlock(&rtc_lock);
440
441	wake_up_interruptible(&rtc_wait);
442
443	kill_fasync(&rtc_async_queue, SIGIO, POLL_IN);
444
445	return IRQ_HANDLED;
446	}
447
448	static irqreturn_t rtclong1_interrupt(int irq, void dev_id, struct pt_regs regs)
449	{
450	unsigned long count = periodic_count;
451
452	spin_lock(&rtc_lock);
453	rtc2_write(RTCINTREG, RTCLONG1_INT);
454
455	rtc1_write(RTCL1LREG, count);
456	rtc1_write(RTCL1HREG, count >> 16);
457
458	rtc_irq_data += 0x100;
459	rtc_irq_data &= ~0xff;
460	rtc_irq_data \|= RTC_PF;
461	spin_unlock(&rtc_lock);
462
463	spin_lock(&rtc_task_lock);
464	if (rtc_callback)
465	rtc_callback->func(rtc_callback->private_data);
466	spin_unlock(&rtc_task_lock);
467
468	wake_up_interruptible(&rtc_wait);
469
470	kill_fasync(&rtc_async_queue, SIGIO, POLL_IN);
471
472	return IRQ_HANDLED;
473	}
474
475	int rtc_register(rtc_task_t *task)
476	{
477	if (task == NULL \|\| task->func == NULL)
478	return -EINVAL;
479
480	spin_lock_irq(&rtc_lock);
481	if (rtc_status == RTC_OPEN) {
482	spin_unlock_irq(&rtc_lock);
483	return -EBUSY;
484	}
485
486	spin_lock(&rtc_task_lock);
487	if (rtc_callback != NULL) {
488	spin_unlock(&rtc_task_lock);
489	spin_unlock_irq(&rtc_task_lock);
490	return -EBUSY;
491	}
492
493	rtc_callback = task;
494	spin_unlock(&rtc_task_lock);
495
496	rtc_status = RTC_OPEN;
497
498	spin_unlock_irq(&rtc_lock);
499
500	return 0;
501	}
502
503	EXPORT_SYMBOL_GPL(rtc_register);
504
505	int rtc_unregister(rtc_task_t *task)
506	{
507	spin_lock_irq(&rtc_task_lock);
508	if (task == NULL \|\| rtc_callback != task) {
509	spin_unlock_irq(&rtc_task_lock);
510	return -ENXIO;
511	}
512
513	spin_lock(&rtc_lock);
514
515	rtc1_write(ECMPLREG, 0);
516	rtc1_write(ECMPMREG, 0);
517	rtc1_write(ECMPHREG, 0);
518	rtc1_write(RTCL1LREG, 0);
519	rtc1_write(RTCL1HREG, 0);
520
521	rtc_status = RTC_RELEASE;
522
523	spin_unlock(&rtc_lock);
524
525	rtc_callback = NULL;
526
527	spin_unlock_irq(&rtc_task_lock);
528
529	disable_irq(ELAPSEDTIME_IRQ);
530	disable_irq(RTCLONG1_IRQ);
531
532	return 0;
533	}
534
535	EXPORT_SYMBOL_GPL(rtc_unregister);
536
537	int rtc_control(rtc_task_t *task, unsigned int cmd, unsigned long arg)
538	{
539	int retval = 0;
540
541	spin_lock_irq(&rtc_task_lock);
542
543	if (rtc_callback != task)
544	retval = -ENXIO;
545	else
546	rtc_do_ioctl(cmd, arg, FUNCTION_RTC_CONTROL);
547
548	spin_unlock_irq(&rtc_task_lock);
549
550	return retval;
551	}
552
553	EXPORT_SYMBOL_GPL(rtc_control);
554
555	static struct miscdevice rtc_miscdevice = {
556	.minor = RTC_MINOR,
557	.name = rtc_name,
558	.fops = &rtc_fops,
559	};
560
d39b6cfe	561	static int __devinit rtc_probe(struct platform_device *pdev)
1da177e4	562	{
1da177e4 LT	563	unsigned int irq;
	564	int retval;
	565
1da177e4 LT	566	if (pdev->num_resources != 2)
	567	return -EBUSY;
	568
	569	rtc1_base = ioremap(pdev->resource[0].start, RTC1_SIZE);
	570	if (rtc1_base == NULL)
	571	return -EBUSY;
	572
	573	rtc2_base = ioremap(pdev->resource[1].start, RTC2_SIZE);
	574	if (rtc2_base == NULL) {
	575	iounmap(rtc1_base);
	576	rtc1_base = NULL;
	577	return -EBUSY;
	578	}
	579
	580	retval = misc_register(&rtc_miscdevice);
	581	if (retval < 0) {
	582	iounmap(rtc1_base);
	583	iounmap(rtc2_base);
	584	rtc1_base = NULL;
	585	rtc2_base = NULL;
	586	return retval;
	587	}
	588
	589	spin_lock_irq(&rtc_lock);
	590
	591	rtc1_write(ECMPLREG, 0);
	592	rtc1_write(ECMPMREG, 0);
	593	rtc1_write(ECMPHREG, 0);
	594	rtc1_write(RTCL1LREG, 0);
	595	rtc1_write(RTCL1HREG, 0);
	596
	597	rtc_status = RTC_RELEASE;
	598	rtc_irq_data = 0;
	599
	600	spin_unlock_irq(&rtc_lock);
	601
	602	init_waitqueue_head(&rtc_wait);
	603
	604	irq = ELAPSEDTIME_IRQ;
	605	retval = request_irq(irq, elapsedtime_interrupt, SA_INTERRUPT,
	606	"elapsed_time", NULL);
	607	if (retval == 0) {
	608	irq = RTCLONG1_IRQ;
	609	retval = request_irq(irq, rtclong1_interrupt, SA_INTERRUPT,
	610	"rtclong1", NULL);
	611	}
	612
	613	if (retval < 0) {
	614	printk(KERN_ERR "rtc: IRQ%d is busy\n", irq);
	615	if (irq == RTCLONG1_IRQ)
	616	free_irq(ELAPSEDTIME_IRQ, NULL);
	617	iounmap(rtc1_base);
	618	iounmap(rtc2_base);
	619	rtc1_base = NULL;
	620	rtc2_base = NULL;
	621	return retval;
	622	}
	623
	624	disable_irq(ELAPSEDTIME_IRQ);
	625	disable_irq(RTCLONG1_IRQ);
	626
	627	spin_lock_init(&rtc_task_lock);
	628
	629	printk(KERN_INFO "rtc: Real Time Clock of NEC VR4100 series\n");
630
631	return 0;
632	}
633
d39b6cfe	634	static int __devexit rtc_remove(struct platform_device *dev)
1da177e4 LT	635	{
	636	int retval;
	637
	638	retval = misc_deregister(&rtc_miscdevice);
	639	if (retval < 0)
	640	return retval;
	641
	642	free_irq(ELAPSEDTIME_IRQ, NULL);
	643	free_irq(RTCLONG1_IRQ, NULL);
	644	if (rtc1_base != NULL)
	645	iounmap(rtc1_base);
	646	if (rtc2_base != NULL)
	647	iounmap(rtc2_base);
	648
	649	return 0;
	650	}
	651
	652	static struct platform_device *rtc_platform_device;
	653
3ae5eaec	654	static struct platform_driver rtc_device_driver = {
1da177e4	655	.probe = rtc_probe,
d39b6cfe	656	.remove = __devexit_p(rtc_remove),
3ae5eaec RK	657	.driver = {
3ae5eaec RK	658	.name = rtc_name,
d39b6cfe	659	.owner = THIS_MODULE,
3ae5eaec	660	},
1da177e4 LT	661	};
1da177e4 LT	662
d39b6cfe	663	static int __init vr41xx_rtc_init(void)
1da177e4 LT	664	{
	665	int retval;
	666
	667	switch (current_cpu_data.cputype) {
	668	case CPU_VR4111:
	669	case CPU_VR4121:
	670	rtc_resource[0].start = RTC1_TYPE1_START;
	671	rtc_resource[0].end = RTC1_TYPE1_END;
	672	rtc_resource[1].start = RTC2_TYPE1_START;
	673	rtc_resource[1].end = RTC2_TYPE1_END;
	674	break;
	675	case CPU_VR4122:
	676	case CPU_VR4131:
	677	case CPU_VR4133:
	678	rtc_resource[0].start = RTC1_TYPE2_START;
	679	rtc_resource[0].end = RTC1_TYPE2_END;
	680	rtc_resource[1].start = RTC2_TYPE2_START;
	681	rtc_resource[1].end = RTC2_TYPE2_END;
	682	break;
	683	default:
	684	return -ENODEV;
	685	break;
	686	}
	687
d39b6cfe DT	688	rtc_platform_device = platform_device_alloc("RTC", -1);
	689	if (!rtc_platform_device)
	690	return -ENOMEM;
	691
	692	retval = platform_device_add_resources(rtc_platform_device,
	693	rtc_resource, ARRAY_SIZE(rtc_resource));
	694
	695	if (retval == 0)
	696	retval = platform_device_add(rtc_platform_device);
	697
	698	if (retval < 0) {
	699	platform_device_put(rtc_platform_device);
	700	return retval;
	701	}
1da177e4	702
3ae5eaec	703	retval = platform_driver_register(&rtc_device_driver);
1da177e4 LT	704	if (retval < 0)
	705	platform_device_unregister(rtc_platform_device);
	706
	707	return retval;
	708	}
	709
d39b6cfe	710	static void __exit vr41xx_rtc_exit(void)
1da177e4	711	{
3ae5eaec	712	platform_driver_unregister(&rtc_device_driver);
1da177e4 LT	713	platform_device_unregister(rtc_platform_device);
	714	}
	715
	716	module_init(vr41xx_rtc_init);
	717	module_exit(vr41xx_rtc_exit);