[deliverable/linux.git] / drivers / rtc / rtc-dev.c

/*
 * RTC subsystem, dev interface
 *
 * Copyright (C) 2005 Tower Technologies
 * Author: Alessandro Zummo <a.zummo@towertech.it>
 *
 * based on arch/arm/common/rtctime.c
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
*/

#include <linux/module.h>
#include <linux/rtc.h>
#include <linux/smp_lock.h>
#include "rtc-core.h"

static dev_t rtc_devt;

#define RTC_DEV_MAX 16 /* 16 RTCs should be enough for everyone... */

static int rtc_dev_open(struct inode *inode, struct file *file)
{
	int err;
	struct rtc_device *rtc = container_of(inode->i_cdev,
					struct rtc_device, char_dev);
	const struct rtc_class_ops *ops = rtc->ops;

	lock_kernel();
	if (test_and_set_bit_lock(RTC_DEV_BUSY, &rtc->flags)) {
		err = -EBUSY;
		goto out;
	}

	file->private_data = rtc;

	err = ops->open ? ops->open(rtc->dev.parent) : 0;
	if (err == 0) {
		spin_lock_irq(&rtc->irq_lock);
		rtc->irq_data = 0;
		spin_unlock_irq(&rtc->irq_lock);

		goto out;
	}

	/* something has gone wrong */
	clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags);
out:
	unlock_kernel();
	return err;
}

#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
/*
 * Routine to poll RTC seconds field for change as often as possible,
 * after first RTC_UIE use timer to reduce polling
 */
static void rtc_uie_task(struct work_struct *work)
{
	struct rtc_device *rtc =
		container_of(work, struct rtc_device, uie_task);
	struct rtc_time tm;
	int num = 0;
	int err;

	err = rtc_read_time(rtc, &tm);

	local_irq_disable();
	spin_lock(&rtc->irq_lock);
	if (rtc->stop_uie_polling || err) {
		rtc->uie_task_active = 0;
	} else if (rtc->oldsecs != tm.tm_sec) {
		num = (tm.tm_sec + 60 - rtc->oldsecs) % 60;
		rtc->oldsecs = tm.tm_sec;
		rtc->uie_timer.expires = jiffies + HZ - (HZ/10);
		rtc->uie_timer_active = 1;
		rtc->uie_task_active = 0;
		add_timer(&rtc->uie_timer);
	} else if (schedule_work(&rtc->uie_task) == 0) {
		rtc->uie_task_active = 0;
	}
	spin_unlock(&rtc->irq_lock);
	if (num)
		rtc_update_irq(rtc, num, RTC_UF | RTC_IRQF);
	local_irq_enable();
}
static void rtc_uie_timer(unsigned long data)
{
	struct rtc_device *rtc = (struct rtc_device *)data;
	unsigned long flags;

	spin_lock_irqsave(&rtc->irq_lock, flags);
	rtc->uie_timer_active = 0;
	rtc->uie_task_active = 1;
	if ((schedule_work(&rtc->uie_task) == 0))
		rtc->uie_task_active = 0;
	spin_unlock_irqrestore(&rtc->irq_lock, flags);
}

static void clear_uie(struct rtc_device *rtc)
{
	spin_lock_irq(&rtc->irq_lock);
	if (rtc->irq_active) {
		rtc->stop_uie_polling = 1;
		if (rtc->uie_timer_active) {
			spin_unlock_irq(&rtc->irq_lock);
			del_timer_sync(&rtc->uie_timer);
			spin_lock_irq(&rtc->irq_lock);
			rtc->uie_timer_active = 0;
		}
		if (rtc->uie_task_active) {
			spin_unlock_irq(&rtc->irq_lock);
			flush_scheduled_work();
			spin_lock_irq(&rtc->irq_lock);
		}
		rtc->irq_active = 0;
	}
	spin_unlock_irq(&rtc->irq_lock);
}

static int set_uie(struct rtc_device *rtc)
{
	struct rtc_time tm;
	int err;

	err = rtc_read_time(rtc, &tm);
	if (err)
		return err;
	spin_lock_irq(&rtc->irq_lock);
	if (!rtc->irq_active) {
		rtc->irq_active = 1;
		rtc->stop_uie_polling = 0;
		rtc->oldsecs = tm.tm_sec;
		rtc->uie_task_active = 1;
		if (schedule_work(&rtc->uie_task) == 0)
			rtc->uie_task_active = 0;
	}
	rtc->irq_data = 0;
	spin_unlock_irq(&rtc->irq_lock);
	return 0;
}
#endif /* CONFIG_RTC_INTF_DEV_UIE_EMUL */

static ssize_t
rtc_dev_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
{
	struct rtc_device *rtc = file->private_data;

	DECLARE_WAITQUEUE(wait, current);
	unsigned long data;
	ssize_t ret;

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

	add_wait_queue(&rtc->irq_queue, &wait);
	do {
		__set_current_state(TASK_INTERRUPTIBLE);

		spin_lock_irq(&rtc->irq_lock);
		data = rtc->irq_data;
		rtc->irq_data = 0;
		spin_unlock_irq(&rtc->irq_lock);

		if (data != 0) {
			ret = 0;
			break;
		}
		if (file->f_flags & O_NONBLOCK) {
			ret = -EAGAIN;
			break;
		}
		if (signal_pending(current)) {
			ret = -ERESTARTSYS;
			break;
		}
		schedule();
	} while (1);
	set_current_state(TASK_RUNNING);
	remove_wait_queue(&rtc->irq_queue, &wait);

	if (ret == 0) {
		/* Check for any data updates */
		if (rtc->ops->read_callback)
			data = rtc->ops->read_callback(rtc->dev.parent,
						       data);

		if (sizeof(int) != sizeof(long) &&
		    count == sizeof(unsigned int))
			ret = put_user(data, (unsigned int __user *)buf) ?:
				sizeof(unsigned int);
		else
			ret = put_user(data, (unsigned long __user *)buf) ?:
				sizeof(unsigned long);
	}
	return ret;
}

static unsigned int rtc_dev_poll(struct file *file, poll_table *wait)
{
	struct rtc_device *rtc = file->private_data;
	unsigned long data;

	poll_wait(file, &rtc->irq_queue, wait);

	data = rtc->irq_data;

	return (data != 0) ? (POLLIN | POLLRDNORM) : 0;
}

static int rtc_dev_ioctl(struct inode *inode, struct file *file,
		unsigned int cmd, unsigned long arg)
{
	int err = 0;
	struct rtc_device *rtc = file->private_data;
	const struct rtc_class_ops *ops = rtc->ops;
	struct rtc_time tm;
	struct rtc_wkalrm alarm;
	void __user *uarg = (void __user *) arg;

	/* check that the calling task has appropriate permissions
	 * for certain ioctls. doing this check here is useful
	 * to avoid duplicate code in each driver.
	 */
	switch (cmd) {
	case RTC_EPOCH_SET:
	case RTC_SET_TIME:
		if (!capable(CAP_SYS_TIME))
			return -EACCES;
		break;

	case RTC_IRQP_SET:
		if (arg > rtc->max_user_freq && !capable(CAP_SYS_RESOURCE))
			return -EACCES;
		break;

	case RTC_PIE_ON:
		if (rtc->irq_freq > rtc->max_user_freq &&
				!capable(CAP_SYS_RESOURCE))
			return -EACCES;
		break;
	}

	/* try the driver's ioctl interface */
	if (ops->ioctl) {
		err = ops->ioctl(rtc->dev.parent, cmd, arg);
		if (err != -ENOIOCTLCMD)
			return err;
	}

	/* if the driver does not provide the ioctl interface
	 * or if that particular ioctl was not implemented
	 * (-ENOIOCTLCMD), we will try to emulate here.
	 *
	 * Drivers *SHOULD NOT* provide ioctl implementations
	 * for these requests.  Instead, provide methods to
	 * support the following code, so that the RTC's main
	 * features are accessible without using ioctls.
	 *
	 * RTC and alarm times will be in UTC, by preference,
	 * but dual-booting with MS-Windows implies RTCs must
	 * use the local wall clock time.
	 */

	switch (cmd) {
	case RTC_ALM_READ:
		err = rtc_read_alarm(rtc, &alarm);
		if (err < 0)
			return err;

		if (copy_to_user(uarg, &alarm.time, sizeof(tm)))
			return -EFAULT;
		break;

	case RTC_ALM_SET:
		if (copy_from_user(&alarm.time, uarg, sizeof(tm)))
			return -EFAULT;

		alarm.enabled = 0;
		alarm.pending = 0;
		alarm.time.tm_wday = -1;
		alarm.time.tm_yday = -1;
		alarm.time.tm_isdst = -1;

		/* RTC_ALM_SET alarms may be up to 24 hours in the future.
		 * Rather than expecting every RTC to implement "don't care"
		 * for day/month/year fields, just force the alarm to have
		 * the right values for those fields.
		 *
		 * RTC_WKALM_SET should be used instead.  Not only does it
		 * eliminate the need for a separate RTC_AIE_ON call, it
		 * doesn't have the "alarm 23:59:59 in the future" race.
		 *
		 * NOTE:  some legacy code may have used invalid fields as
		 * wildcards, exposing hardware "periodic alarm" capabilities.
		 * Not supported here.
		 */
		{
			unsigned long now, then;

			err = rtc_read_time(rtc, &tm);
			if (err < 0)
				return err;
			rtc_tm_to_time(&tm, &now);

			alarm.time.tm_mday = tm.tm_mday;
			alarm.time.tm_mon = tm.tm_mon;
			alarm.time.tm_year = tm.tm_year;
			err  = rtc_valid_tm(&alarm.time);
			if (err < 0)
				return err;
			rtc_tm_to_time(&alarm.time, &then);

			/* alarm may need to wrap into tomorrow */
			if (then < now) {
				rtc_time_to_tm(now + 24 * 60 * 60, &tm);
				alarm.time.tm_mday = tm.tm_mday;
				alarm.time.tm_mon = tm.tm_mon;
				alarm.time.tm_year = tm.tm_year;
			}
		}

		err = rtc_set_alarm(rtc, &alarm);
		break;

	case RTC_RD_TIME:
		err = rtc_read_time(rtc, &tm);
		if (err < 0)
			return err;

		if (copy_to_user(uarg, &tm, sizeof(tm)))
			return -EFAULT;
		break;

	case RTC_SET_TIME:
		if (copy_from_user(&tm, uarg, sizeof(tm)))
			return -EFAULT;

		err = rtc_set_time(rtc, &tm);
		break;

	case RTC_PIE_ON:
		err = rtc_irq_set_state(rtc, NULL, 1);
		break;

	case RTC_PIE_OFF:
		err = rtc_irq_set_state(rtc, NULL, 0);
		break;

	case RTC_IRQP_SET:
		err = rtc_irq_set_freq(rtc, NULL, arg);
		break;

	case RTC_IRQP_READ:
		err = put_user(rtc->irq_freq, (unsigned long __user *)uarg);
		break;

#if 0
	case RTC_EPOCH_SET:
#ifndef rtc_epoch
		/*
		 * There were no RTC clocks before 1900.
		 */
		if (arg < 1900) {
			err = -EINVAL;
			break;
		}
		rtc_epoch = arg;
		err = 0;
#endif
		break;

	case RTC_EPOCH_READ:
		err = put_user(rtc_epoch, (unsigned long __user *)uarg);
		break;
#endif
	case RTC_WKALM_SET:
		if (copy_from_user(&alarm, uarg, sizeof(alarm)))
			return -EFAULT;

		err = rtc_set_alarm(rtc, &alarm);
		break;

	case RTC_WKALM_RD:
		err = rtc_read_alarm(rtc, &alarm);
		if (err < 0)
			return err;

		if (copy_to_user(uarg, &alarm, sizeof(alarm)))
			return -EFAULT;
		break;

#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
	case RTC_UIE_OFF:
		clear_uie(rtc);
		return 0;

	case RTC_UIE_ON:
		return set_uie(rtc);
#endif
	default:
		err = -ENOTTY;
		break;
	}

	return err;
}

static int rtc_dev_release(struct inode *inode, struct file *file)
{
	struct rtc_device *rtc = file->private_data;

#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
	clear_uie(rtc);
#endif
	if (rtc->ops->release)
		rtc->ops->release(rtc->dev.parent);

	clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags);
	return 0;
}

static int rtc_dev_fasync(int fd, struct file *file, int on)
{
	struct rtc_device *rtc = file->private_data;
	return fasync_helper(fd, file, on, &rtc->async_queue);
}

static const struct file_operations rtc_dev_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.read		= rtc_dev_read,
	.poll		= rtc_dev_poll,
	.ioctl		= rtc_dev_ioctl,
	.open		= rtc_dev_open,
	.release	= rtc_dev_release,
	.fasync		= rtc_dev_fasync,
};

/* insertion/removal hooks */

void rtc_dev_prepare(struct rtc_device *rtc)
{
	if (!rtc_devt)
		return;

	if (rtc->id >= RTC_DEV_MAX) {
		pr_debug("%s: too many RTC devices\n", rtc->name);
		return;
	}

	rtc->dev.devt = MKDEV(MAJOR(rtc_devt), rtc->id);

#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
	INIT_WORK(&rtc->uie_task, rtc_uie_task);
	setup_timer(&rtc->uie_timer, rtc_uie_timer, (unsigned long)rtc);
#endif

	cdev_init(&rtc->char_dev, &rtc_dev_fops);
	rtc->char_dev.owner = rtc->owner;
}

void rtc_dev_add_device(struct rtc_device *rtc)
{
	if (cdev_add(&rtc->char_dev, rtc->dev.devt, 1))
		printk(KERN_WARNING "%s: failed to add char device %d:%d\n",
			rtc->name, MAJOR(rtc_devt), rtc->id);
	else
		pr_debug("%s: dev (%d:%d)\n", rtc->name,
			MAJOR(rtc_devt), rtc->id);
}

void rtc_dev_del_device(struct rtc_device *rtc)
{
	if (rtc->dev.devt)
		cdev_del(&rtc->char_dev);
}

void __init rtc_dev_init(void)
{
	int err;

	err = alloc_chrdev_region(&rtc_devt, 0, RTC_DEV_MAX, "rtc");
	if (err < 0)
		printk(KERN_ERR "%s: failed to allocate char dev region\n",
			__FILE__);
}

void __exit rtc_dev_exit(void)
{
	if (rtc_devt)
		unregister_chrdev_region(rtc_devt, RTC_DEV_MAX);
}
Commit	Line	Data
e824290e AZ	1	/*
	2	* RTC subsystem, dev interface
	3	*
	4	* Copyright (C) 2005 Tower Technologies
	5	* Author: Alessandro Zummo <a.zummo@towertech.it>
	6	*
	7	* based on arch/arm/common/rtctime.c
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License version 2 as
	11	* published by the Free Software Foundation.
	12	*/
	13
	14	#include <linux/module.h>
	15	#include <linux/rtc.h>
51a776fa	16	#include <linux/smp_lock.h>
5726fb20	17	#include "rtc-core.h"
e824290e	18
e824290e AZ	19	static dev_t rtc_devt;
	20
	21	#define RTC_DEV_MAX 16 /* 16 RTCs should be enough for everyone... */
	22
	23	static int rtc_dev_open(struct inode inode, struct file file)
	24	{
	25	int err;
	26	struct rtc_device *rtc = container_of(inode->i_cdev,
	27	struct rtc_device, char_dev);
ff8371ac	28	const struct rtc_class_ops *ops = rtc->ops;
e824290e	29
51a776fa JC	30	lock_kernel();
	31	if (test_and_set_bit_lock(RTC_DEV_BUSY, &rtc->flags)) {
	32	err = -EBUSY;
	33	goto out;
	34	}
e824290e	35
ab6a2d70	36	file->private_data = rtc;
e824290e	37
cd966209	38	err = ops->open ? ops->open(rtc->dev.parent) : 0;
e824290e AZ	39	if (err == 0) {
	40	spin_lock_irq(&rtc->irq_lock);
	41	rtc->irq_data = 0;
	42	spin_unlock_irq(&rtc->irq_lock);
	43
51a776fa	44	goto out;
e824290e AZ	45	}
e824290e AZ	46
8853c202	47	/* something has gone wrong */
372a302e	48	clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags);
51a776fa JC	49	out:
51a776fa JC	50	unlock_kernel();
e824290e AZ	51	return err;
	52	}
	53
655066c3 AN	54	#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
	55	/*
	56	* Routine to poll RTC seconds field for change as often as possible,
	57	* after first RTC_UIE use timer to reduce polling
	58	*/
c4028958	59	static void rtc_uie_task(struct work_struct *work)
655066c3	60	{
c4028958 DH	61	struct rtc_device *rtc =
c4028958 DH	62	container_of(work, struct rtc_device, uie_task);
655066c3 AN	63	struct rtc_time tm;
	64	int num = 0;
	65	int err;
	66
ab6a2d70	67	err = rtc_read_time(rtc, &tm);
d728b1e6 DB	68
	69	local_irq_disable();
	70	spin_lock(&rtc->irq_lock);
655066c3 AN	71	if (rtc->stop_uie_polling \|\| err) {
	72	rtc->uie_task_active = 0;
	73	} else if (rtc->oldsecs != tm.tm_sec) {
	74	num = (tm.tm_sec + 60 - rtc->oldsecs) % 60;
	75	rtc->oldsecs = tm.tm_sec;
	76	rtc->uie_timer.expires = jiffies + HZ - (HZ/10);
	77	rtc->uie_timer_active = 1;
	78	rtc->uie_task_active = 0;
	79	add_timer(&rtc->uie_timer);
	80	} else if (schedule_work(&rtc->uie_task) == 0) {
	81	rtc->uie_task_active = 0;
	82	}
d728b1e6	83	spin_unlock(&rtc->irq_lock);
655066c3	84	if (num)
ab6a2d70	85	rtc_update_irq(rtc, num, RTC_UF \| RTC_IRQF);
d728b1e6	86	local_irq_enable();
655066c3	87	}
655066c3 AN	88	static void rtc_uie_timer(unsigned long data)
	89	{
	90	struct rtc_device rtc = (struct rtc_device )data;
	91	unsigned long flags;
	92
	93	spin_lock_irqsave(&rtc->irq_lock, flags);
	94	rtc->uie_timer_active = 0;
	95	rtc->uie_task_active = 1;
	96	if ((schedule_work(&rtc->uie_task) == 0))
	97	rtc->uie_task_active = 0;
	98	spin_unlock_irqrestore(&rtc->irq_lock, flags);
	99	}
	100
	101	static void clear_uie(struct rtc_device *rtc)
	102	{
	103	spin_lock_irq(&rtc->irq_lock);
	104	if (rtc->irq_active) {
	105	rtc->stop_uie_polling = 1;
	106	if (rtc->uie_timer_active) {
	107	spin_unlock_irq(&rtc->irq_lock);
	108	del_timer_sync(&rtc->uie_timer);
	109	spin_lock_irq(&rtc->irq_lock);
	110	rtc->uie_timer_active = 0;
	111	}
	112	if (rtc->uie_task_active) {
	113	spin_unlock_irq(&rtc->irq_lock);
	114	flush_scheduled_work();
	115	spin_lock_irq(&rtc->irq_lock);
	116	}
	117	rtc->irq_active = 0;
	118	}
	119	spin_unlock_irq(&rtc->irq_lock);
	120	}
	121
	122	static int set_uie(struct rtc_device *rtc)
	123	{
	124	struct rtc_time tm;
	125	int err;
	126
ab6a2d70	127	err = rtc_read_time(rtc, &tm);
655066c3 AN	128	if (err)
	129	return err;
	130	spin_lock_irq(&rtc->irq_lock);
	131	if (!rtc->irq_active) {
	132	rtc->irq_active = 1;
	133	rtc->stop_uie_polling = 0;
	134	rtc->oldsecs = tm.tm_sec;
	135	rtc->uie_task_active = 1;
	136	if (schedule_work(&rtc->uie_task) == 0)
	137	rtc->uie_task_active = 0;
	138	}
	139	rtc->irq_data = 0;
	140	spin_unlock_irq(&rtc->irq_lock);
	141	return 0;
	142	}
	143	#endif /* CONFIG_RTC_INTF_DEV_UIE_EMUL */
e824290e AZ	144
	145	static ssize_t
	146	rtc_dev_read(struct file file, char __user buf, size_t count, loff_t *ppos)
	147	{
88efe137	148	struct rtc_device *rtc = file->private_data;
e824290e AZ	149
	150	DECLARE_WAITQUEUE(wait, current);
	151	unsigned long data;
	152	ssize_t ret;
	153
3418ff76	154	if (count != sizeof(unsigned int) && count < sizeof(unsigned long))
e824290e AZ	155	return -EINVAL;
	156
	157	add_wait_queue(&rtc->irq_queue, &wait);
	158	do {
	159	__set_current_state(TASK_INTERRUPTIBLE);
	160
	161	spin_lock_irq(&rtc->irq_lock);
	162	data = rtc->irq_data;
	163	rtc->irq_data = 0;
	164	spin_unlock_irq(&rtc->irq_lock);
	165
	166	if (data != 0) {
	167	ret = 0;
	168	break;
	169	}
	170	if (file->f_flags & O_NONBLOCK) {
	171	ret = -EAGAIN;
	172	break;
	173	}
	174	if (signal_pending(current)) {
	175	ret = -ERESTARTSYS;
	176	break;
	177	}
	178	schedule();
	179	} while (1);
	180	set_current_state(TASK_RUNNING);
	181	remove_wait_queue(&rtc->irq_queue, &wait);
	182
	183	if (ret == 0) {
	184	/* Check for any data updates */
	185	if (rtc->ops->read_callback)
cd966209	186	data = rtc->ops->read_callback(rtc->dev.parent,
3418ff76 AN	187	data);
	188
	189	if (sizeof(int) != sizeof(long) &&
	190	count == sizeof(unsigned int))
	191	ret = put_user(data, (unsigned int __user *)buf) ?:
	192	sizeof(unsigned int);
	193	else
	194	ret = put_user(data, (unsigned long __user *)buf) ?:
	195	sizeof(unsigned long);
e824290e AZ	196	}
	197	return ret;
	198	}
	199
	200	static unsigned int rtc_dev_poll(struct file file, poll_table wait)
	201	{
88efe137	202	struct rtc_device *rtc = file->private_data;
e824290e AZ	203	unsigned long data;
	204
	205	poll_wait(file, &rtc->irq_queue, wait);
	206
	207	data = rtc->irq_data;
	208
	209	return (data != 0) ? (POLLIN \| POLLRDNORM) : 0;
	210	}
	211
	212	static int rtc_dev_ioctl(struct inode inode, struct file file,
	213	unsigned int cmd, unsigned long arg)
	214	{
	215	int err = 0;
ab6a2d70	216	struct rtc_device *rtc = file->private_data;
ff8371ac	217	const struct rtc_class_ops *ops = rtc->ops;
e824290e AZ	218	struct rtc_time tm;
	219	struct rtc_wkalrm alarm;
	220	void __user uarg = (void __user ) arg;
	221
2601a464	222	/* check that the calling task has appropriate permissions
110d693d AZ	223	* for certain ioctls. doing this check here is useful
	224	* to avoid duplicate code in each driver.
	225	*/
	226	switch (cmd) {
	227	case RTC_EPOCH_SET:
	228	case RTC_SET_TIME:
	229	if (!capable(CAP_SYS_TIME))
	230	return -EACCES;
	231	break;
	232
	233	case RTC_IRQP_SET:
	234	if (arg > rtc->max_user_freq && !capable(CAP_SYS_RESOURCE))
	235	return -EACCES;
	236	break;
	237
	238	case RTC_PIE_ON:
9d013d3b BK	239	if (rtc->irq_freq > rtc->max_user_freq &&
9d013d3b BK	240	!capable(CAP_SYS_RESOURCE))
110d693d AZ	241	return -EACCES;
	242	break;
	243	}
	244
e824290e AZ	245	/* try the driver's ioctl interface */
e824290e AZ	246	if (ops->ioctl) {
cd966209	247	err = ops->ioctl(rtc->dev.parent, cmd, arg);
b3969e58	248	if (err != -ENOIOCTLCMD)
e824290e AZ	249	return err;
	250	}
	251
	252	/* if the driver does not provide the ioctl interface
	253	* or if that particular ioctl was not implemented
b3969e58	254	* (-ENOIOCTLCMD), we will try to emulate here.
8a0bdfd7 DB	255	*
	256	* Drivers SHOULD NOT provide ioctl implementations
	257	* for these requests. Instead, provide methods to
	258	* support the following code, so that the RTC's main
	259	* features are accessible without using ioctls.
	260	*
	261	* RTC and alarm times will be in UTC, by preference,
	262	* but dual-booting with MS-Windows implies RTCs must
	263	* use the local wall clock time.
e824290e AZ	264	*/
	265
	266	switch (cmd) {
	267	case RTC_ALM_READ:
ab6a2d70	268	err = rtc_read_alarm(rtc, &alarm);
e824290e AZ	269	if (err < 0)
	270	return err;
	271
	272	if (copy_to_user(uarg, &alarm.time, sizeof(tm)))
	273	return -EFAULT;
	274	break;
	275
	276	case RTC_ALM_SET:
	277	if (copy_from_user(&alarm.time, uarg, sizeof(tm)))
	278	return -EFAULT;
	279
	280	alarm.enabled = 0;
	281	alarm.pending = 0;
e824290e AZ	282	alarm.time.tm_wday = -1;
	283	alarm.time.tm_yday = -1;
	284	alarm.time.tm_isdst = -1;
f8245c26 DB	285
	286	/* RTC_ALM_SET alarms may be up to 24 hours in the future.
	287	* Rather than expecting every RTC to implement "don't care"
	288	* for day/month/year fields, just force the alarm to have
	289	* the right values for those fields.
	290	*
	291	* RTC_WKALM_SET should be used instead. Not only does it
	292	* eliminate the need for a separate RTC_AIE_ON call, it
	293	* doesn't have the "alarm 23:59:59 in the future" race.
	294	*
	295	* NOTE: some legacy code may have used invalid fields as
	296	* wildcards, exposing hardware "periodic alarm" capabilities.
	297	* Not supported here.
	298	*/
	299	{
	300	unsigned long now, then;
	301
	302	err = rtc_read_time(rtc, &tm);
	303	if (err < 0)
	304	return err;
	305	rtc_tm_to_time(&tm, &now);
	306
	307	alarm.time.tm_mday = tm.tm_mday;
	308	alarm.time.tm_mon = tm.tm_mon;
	309	alarm.time.tm_year = tm.tm_year;
	310	err = rtc_valid_tm(&alarm.time);
	311	if (err < 0)
	312	return err;
	313	rtc_tm_to_time(&alarm.time, &then);
	314
	315	/* alarm may need to wrap into tomorrow */
	316	if (then < now) {
	317	rtc_time_to_tm(now + 24 * 60 * 60, &tm);
	318	alarm.time.tm_mday = tm.tm_mday;
	319	alarm.time.tm_mon = tm.tm_mon;
	320	alarm.time.tm_year = tm.tm_year;
	321	}
	322	}
	323
ab6a2d70	324	err = rtc_set_alarm(rtc, &alarm);
e824290e AZ	325	break;
	326
	327	case RTC_RD_TIME:
ab6a2d70	328	err = rtc_read_time(rtc, &tm);
e824290e AZ	329	if (err < 0)
	330	return err;
	331
	332	if (copy_to_user(uarg, &tm, sizeof(tm)))
	333	return -EFAULT;
	334	break;
	335
	336	case RTC_SET_TIME:
e824290e AZ	337	if (copy_from_user(&tm, uarg, sizeof(tm)))
	338	return -EFAULT;
	339
ab6a2d70	340	err = rtc_set_time(rtc, &tm);
e824290e	341	break;
2601a464	342
d691eb90 AZ	343	case RTC_PIE_ON:
	344	err = rtc_irq_set_state(rtc, NULL, 1);
	345	break;
	346
	347	case RTC_PIE_OFF:
	348	err = rtc_irq_set_state(rtc, NULL, 0);
2601a464 DB	349	break;
	350
	351	case RTC_IRQP_SET:
d691eb90 AZ	352	err = rtc_irq_set_freq(rtc, NULL, arg);
	353	break;
	354
	355	case RTC_IRQP_READ:
	356	err = put_user(rtc->irq_freq, (unsigned long __user *)uarg);
2601a464 DB	357	break;
2601a464 DB	358
e824290e AZ	359	#if 0
	360	case RTC_EPOCH_SET:
	361	#ifndef rtc_epoch
	362	/*
	363	* There were no RTC clocks before 1900.
	364	*/
	365	if (arg < 1900) {
	366	err = -EINVAL;
	367	break;
	368	}
e824290e AZ	369	rtc_epoch = arg;
	370	err = 0;
	371	#endif
	372	break;
	373
	374	case RTC_EPOCH_READ:
	375	err = put_user(rtc_epoch, (unsigned long __user *)uarg);
	376	break;
	377	#endif
	378	case RTC_WKALM_SET:
	379	if (copy_from_user(&alarm, uarg, sizeof(alarm)))
	380	return -EFAULT;
	381
ab6a2d70	382	err = rtc_set_alarm(rtc, &alarm);
e824290e AZ	383	break;
	384
	385	case RTC_WKALM_RD:
ab6a2d70	386	err = rtc_read_alarm(rtc, &alarm);
e824290e AZ	387	if (err < 0)
	388	return err;
	389
	390	if (copy_to_user(uarg, &alarm, sizeof(alarm)))
	391	return -EFAULT;
	392	break;
	393
655066c3 AN	394	#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
	395	case RTC_UIE_OFF:
	396	clear_uie(rtc);
	397	return 0;
	398
	399	case RTC_UIE_ON:
	400	return set_uie(rtc);
	401	#endif
e824290e	402	default:
b3969e58	403	err = -ENOTTY;
e824290e AZ	404	break;
	405	}
	406
	407	return err;
	408	}
	409
	410	static int rtc_dev_release(struct inode inode, struct file file)
	411	{
88efe137	412	struct rtc_device *rtc = file->private_data;
e824290e	413
655066c3 AN	414	#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
	415	clear_uie(rtc);
	416	#endif
e824290e	417	if (rtc->ops->release)
cd966209	418	rtc->ops->release(rtc->dev.parent);
e824290e	419
372a302e	420	clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags);
e824290e AZ	421	return 0;
	422	}
	423
	424	static int rtc_dev_fasync(int fd, struct file *file, int on)
	425	{
88efe137	426	struct rtc_device *rtc = file->private_data;
e824290e AZ	427	return fasync_helper(fd, file, on, &rtc->async_queue);
	428	}
	429
d54b1fdb	430	static const struct file_operations rtc_dev_fops = {
e824290e AZ	431	.owner = THIS_MODULE,
	432	.llseek = no_llseek,
	433	.read = rtc_dev_read,
	434	.poll = rtc_dev_poll,
	435	.ioctl = rtc_dev_ioctl,
	436	.open = rtc_dev_open,
	437	.release = rtc_dev_release,
	438	.fasync = rtc_dev_fasync,
	439	};
	440
	441	/* insertion/removal hooks */
	442
cb3a58d2	443	void rtc_dev_prepare(struct rtc_device *rtc)
e824290e	444	{
5726fb20 DB	445	if (!rtc_devt)
5726fb20 DB	446	return;
e824290e AZ	447
e824290e AZ	448	if (rtc->id >= RTC_DEV_MAX) {
5726fb20 DB	449	pr_debug("%s: too many RTC devices\n", rtc->name);
5726fb20 DB	450	return;
e824290e AZ	451	}
e824290e AZ	452
cd966209	453	rtc->dev.devt = MKDEV(MAJOR(rtc_devt), rtc->id);
5726fb20	454
655066c3	455	#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
c4028958	456	INIT_WORK(&rtc->uie_task, rtc_uie_task);
655066c3 AN	457	setup_timer(&rtc->uie_timer, rtc_uie_timer, (unsigned long)rtc);
655066c3 AN	458	#endif
e824290e AZ	459
	460	cdev_init(&rtc->char_dev, &rtc_dev_fops);
	461	rtc->char_dev.owner = rtc->owner;
cb3a58d2	462	}
e824290e	463
cb3a58d2 DB	464	void rtc_dev_add_device(struct rtc_device *rtc)
cb3a58d2 DB	465	{
cd966209	466	if (cdev_add(&rtc->char_dev, rtc->dev.devt, 1))
5726fb20 DB	467	printk(KERN_WARNING "%s: failed to add char device %d:%d\n",
	468	rtc->name, MAJOR(rtc_devt), rtc->id);
	469	else
	470	pr_debug("%s: dev (%d:%d)\n", rtc->name,
e824290e	471	MAJOR(rtc_devt), rtc->id);
e824290e AZ	472	}
e824290e AZ	473
5726fb20	474	void rtc_dev_del_device(struct rtc_device *rtc)
e824290e	475	{
cd966209	476	if (rtc->dev.devt)
e824290e	477	cdev_del(&rtc->char_dev);
e824290e AZ	478	}
e824290e AZ	479
5726fb20	480	void __init rtc_dev_init(void)
e824290e AZ	481	{
	482	int err;
	483
e824290e	484	err = alloc_chrdev_region(&rtc_devt, 0, RTC_DEV_MAX, "rtc");
5726fb20	485	if (err < 0)
e824290e AZ	486	printk(KERN_ERR "%s: failed to allocate char dev region\n",
e824290e AZ	487	__FILE__);
e824290e AZ	488	}
e824290e AZ	489
5726fb20	490	void __exit rtc_dev_exit(void)
e824290e	491	{
5726fb20 DB	492	if (rtc_devt)
5726fb20 DB	493	unregister_chrdev_region(rtc_devt, RTC_DEV_MAX);
e824290e	494	}