[net-next-2.6.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>

static struct class *rtc_dev_class;
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;

	/* We keep the lock as long as the device is in use
	 * and return immediately if busy
	 */
	if (!(mutex_trylock(&rtc->char_lock)))
		return -EBUSY;

	file->private_data = &rtc->class_dev;

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

		return 0;
	}

	/* something has gone wrong, release the lock */
	mutex_unlock(&rtc->char_lock);
	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->class_dev, &tm);
	spin_lock_irq(&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_irq(&rtc->irq_lock);
	if (num)
		rtc_update_irq(&rtc->class_dev, num, RTC_UF | RTC_IRQF);
}

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->class_dev, &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 = to_rtc_device(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->class_dev.dev,
						       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 = to_rtc_device(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 class_device *class_dev = file->private_data;
	struct rtc_device *rtc = to_rtc_device(class_dev);
	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 calles 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 (!capable(CAP_SYS_RESOURCE))
			return -EACCES;
		break;
	}

	/* avoid conflicting IRQ users */
	if (cmd == RTC_PIE_ON || cmd == RTC_PIE_OFF || cmd == RTC_IRQP_SET) {
		spin_lock(&rtc->irq_task_lock);
		if (rtc->irq_task)
			err = -EBUSY;
		spin_unlock(&rtc->irq_task_lock);

		if (err < 0)
			return err;
	}

	/* try the driver's ioctl interface */
	if (ops->ioctl) {
		err = ops->ioctl(class_dev->dev, 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.
	 */

	switch (cmd) {
	case RTC_ALM_READ:
		err = rtc_read_alarm(class_dev, &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_mday = -1;
		alarm.time.tm_mon = -1;
		alarm.time.tm_year = -1;
		alarm.time.tm_wday = -1;
		alarm.time.tm_yday = -1;
		alarm.time.tm_isdst = -1;
		err = rtc_set_alarm(class_dev, &alarm);
		break;

	case RTC_RD_TIME:
		err = rtc_read_time(class_dev, &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(class_dev, &tm);
		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(class_dev, &alarm);
		break;

	case RTC_WKALM_RD:
		err = rtc_read_alarm(class_dev, &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 = to_rtc_device(file->private_data);

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

	mutex_unlock(&rtc->char_lock);
	return 0;
}

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

static 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 */

static int rtc_dev_add_device(struct class_device *class_dev,
				struct class_interface *class_intf)
{
	int err = 0;
	struct rtc_device *rtc = to_rtc_device(class_dev);

	if (rtc->id >= RTC_DEV_MAX) {
		dev_err(class_dev->dev, "too many RTCs\n");
		return -EINVAL;
	}

	mutex_init(&rtc->char_lock);
	spin_lock_init(&rtc->irq_lock);
	init_waitqueue_head(&rtc->irq_queue);
#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;

	if (cdev_add(&rtc->char_dev, MKDEV(MAJOR(rtc_devt), rtc->id), 1)) {
		dev_err(class_dev->dev,
			"failed to add char device %d:%d\n",
			MAJOR(rtc_devt), rtc->id);
		return -ENODEV;
	}

	rtc->rtc_dev = class_device_create(rtc_dev_class, NULL,
						MKDEV(MAJOR(rtc_devt), rtc->id),
						class_dev->dev, "rtc%d", rtc->id);
	if (IS_ERR(rtc->rtc_dev)) {
		dev_err(class_dev->dev, "cannot create rtc_dev device\n");
		err = PTR_ERR(rtc->rtc_dev);
		goto err_cdev_del;
	}

	dev_info(class_dev->dev, "rtc intf: dev (%d:%d)\n",
		MAJOR(rtc->rtc_dev->devt),
		MINOR(rtc->rtc_dev->devt));

	return 0;

err_cdev_del:

	cdev_del(&rtc->char_dev);
	return err;
}

static void rtc_dev_remove_device(struct class_device *class_dev,
					struct class_interface *class_intf)
{
	struct rtc_device *rtc = to_rtc_device(class_dev);

	if (rtc->rtc_dev) {
		dev_dbg(class_dev->dev, "removing char %d:%d\n",
			MAJOR(rtc->rtc_dev->devt),
			MINOR(rtc->rtc_dev->devt));

		class_device_unregister(rtc->rtc_dev);
		cdev_del(&rtc->char_dev);
	}
}

/* interface registration */

static struct class_interface rtc_dev_interface = {
	.add = &rtc_dev_add_device,
	.remove = &rtc_dev_remove_device,
};

static int __init rtc_dev_init(void)
{
	int err;

	rtc_dev_class = class_create(THIS_MODULE, "rtc-dev");
	if (IS_ERR(rtc_dev_class))
		return PTR_ERR(rtc_dev_class);

	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__);
		goto err_destroy_class;
	}

	err = rtc_interface_register(&rtc_dev_interface);
	if (err < 0) {
		printk(KERN_ERR "%s: failed to register the interface\n",
			__FILE__);
		goto err_unregister_chrdev;
	}

	return 0;

err_unregister_chrdev:
	unregister_chrdev_region(rtc_devt, RTC_DEV_MAX);

err_destroy_class:
	class_destroy(rtc_dev_class);

	return err;
}

static void __exit rtc_dev_exit(void)
{
	class_interface_unregister(&rtc_dev_interface);
	class_destroy(rtc_dev_class);
	unregister_chrdev_region(rtc_devt, RTC_DEV_MAX);
}

subsys_initcall(rtc_dev_init);
module_exit(rtc_dev_exit);

MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
MODULE_DESCRIPTION("RTC class dev interface");
MODULE_LICENSE("GPL");
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>
	16
	17	static struct class *rtc_dev_class;
	18	static dev_t rtc_devt;
	19
	20	#define RTC_DEV_MAX 16 /* 16 RTCs should be enough for everyone... */
	21
	22	static int rtc_dev_open(struct inode inode, struct file file)
	23	{
	24	int err;
	25	struct rtc_device *rtc = container_of(inode->i_cdev,
	26	struct rtc_device, char_dev);
ff8371ac	27	const struct rtc_class_ops *ops = rtc->ops;
e824290e AZ	28
	29	/* We keep the lock as long as the device is in use
	30	* and return immediately if busy
	31	*/
	32	if (!(mutex_trylock(&rtc->char_lock)))
	33	return -EBUSY;
	34
	35	file->private_data = &rtc->class_dev;
	36
	37	err = ops->open ? ops->open(rtc->class_dev.dev) : 0;
	38	if (err == 0) {
	39	spin_lock_irq(&rtc->irq_lock);
	40	rtc->irq_data = 0;
	41	spin_unlock_irq(&rtc->irq_lock);
	42
	43	return 0;
	44	}
	45
	46	/* something has gone wrong, release the lock */
	47	mutex_unlock(&rtc->char_lock);
	48	return err;
	49	}
	50
655066c3 AN	51	#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
	52	/*
	53	* Routine to poll RTC seconds field for change as often as possible,
	54	* after first RTC_UIE use timer to reduce polling
	55	*/
c4028958	56	static void rtc_uie_task(struct work_struct *work)
655066c3	57	{
c4028958 DH	58	struct rtc_device *rtc =
c4028958 DH	59	container_of(work, struct rtc_device, uie_task);
655066c3 AN	60	struct rtc_time tm;
	61	int num = 0;
	62	int err;
	63
	64	err = rtc_read_time(&rtc->class_dev, &tm);
	65	spin_lock_irq(&rtc->irq_lock);
	66	if (rtc->stop_uie_polling \|\| err) {
	67	rtc->uie_task_active = 0;
	68	} else if (rtc->oldsecs != tm.tm_sec) {
	69	num = (tm.tm_sec + 60 - rtc->oldsecs) % 60;
	70	rtc->oldsecs = tm.tm_sec;
	71	rtc->uie_timer.expires = jiffies + HZ - (HZ/10);
	72	rtc->uie_timer_active = 1;
	73	rtc->uie_task_active = 0;
	74	add_timer(&rtc->uie_timer);
	75	} else if (schedule_work(&rtc->uie_task) == 0) {
	76	rtc->uie_task_active = 0;
	77	}
	78	spin_unlock_irq(&rtc->irq_lock);
	79	if (num)
	80	rtc_update_irq(&rtc->class_dev, num, RTC_UF \| RTC_IRQF);
	81	}
	82
	83	static void rtc_uie_timer(unsigned long data)
	84	{
	85	struct rtc_device rtc = (struct rtc_device )data;
	86	unsigned long flags;
	87
	88	spin_lock_irqsave(&rtc->irq_lock, flags);
	89	rtc->uie_timer_active = 0;
	90	rtc->uie_task_active = 1;
	91	if ((schedule_work(&rtc->uie_task) == 0))
	92	rtc->uie_task_active = 0;
	93	spin_unlock_irqrestore(&rtc->irq_lock, flags);
	94	}
	95
	96	static void clear_uie(struct rtc_device *rtc)
	97	{
	98	spin_lock_irq(&rtc->irq_lock);
	99	if (rtc->irq_active) {
	100	rtc->stop_uie_polling = 1;
	101	if (rtc->uie_timer_active) {
	102	spin_unlock_irq(&rtc->irq_lock);
	103	del_timer_sync(&rtc->uie_timer);
	104	spin_lock_irq(&rtc->irq_lock);
	105	rtc->uie_timer_active = 0;
	106	}
	107	if (rtc->uie_task_active) {
	108	spin_unlock_irq(&rtc->irq_lock);
	109	flush_scheduled_work();
	110	spin_lock_irq(&rtc->irq_lock);
	111	}
	112	rtc->irq_active = 0;
	113	}
	114	spin_unlock_irq(&rtc->irq_lock);
	115	}
	116
	117	static int set_uie(struct rtc_device *rtc)
	118	{
	119	struct rtc_time tm;
	120	int err;
	121
	122	err = rtc_read_time(&rtc->class_dev, &tm);
	123	if (err)
124	return err;
125	spin_lock_irq(&rtc->irq_lock);
126	if (!rtc->irq_active) {
127	rtc->irq_active = 1;
128	rtc->stop_uie_polling = 0;
129	rtc->oldsecs = tm.tm_sec;
130	rtc->uie_task_active = 1;
131	if (schedule_work(&rtc->uie_task) == 0)
132	rtc->uie_task_active = 0;
133	}
134	rtc->irq_data = 0;
135	spin_unlock_irq(&rtc->irq_lock);
136	return 0;
137	}
138	#endif /* CONFIG_RTC_INTF_DEV_UIE_EMUL */
e824290e AZ	139
	140	static ssize_t
	141	rtc_dev_read(struct file file, char __user buf, size_t count, loff_t *ppos)
	142	{
	143	struct rtc_device *rtc = to_rtc_device(file->private_data);
	144
	145	DECLARE_WAITQUEUE(wait, current);
	146	unsigned long data;
	147	ssize_t ret;
	148
3418ff76	149	if (count != sizeof(unsigned int) && count < sizeof(unsigned long))
e824290e AZ	150	return -EINVAL;
	151
	152	add_wait_queue(&rtc->irq_queue, &wait);
	153	do {
	154	__set_current_state(TASK_INTERRUPTIBLE);
	155
	156	spin_lock_irq(&rtc->irq_lock);
	157	data = rtc->irq_data;
	158	rtc->irq_data = 0;
	159	spin_unlock_irq(&rtc->irq_lock);
	160
	161	if (data != 0) {
	162	ret = 0;
	163	break;
	164	}
	165	if (file->f_flags & O_NONBLOCK) {
	166	ret = -EAGAIN;
	167	break;
	168	}
	169	if (signal_pending(current)) {
	170	ret = -ERESTARTSYS;
	171	break;
	172	}
	173	schedule();
	174	} while (1);
	175	set_current_state(TASK_RUNNING);
	176	remove_wait_queue(&rtc->irq_queue, &wait);
	177
	178	if (ret == 0) {
	179	/* Check for any data updates */
	180	if (rtc->ops->read_callback)
3418ff76 AN	181	data = rtc->ops->read_callback(rtc->class_dev.dev,
	182	data);
	183
	184	if (sizeof(int) != sizeof(long) &&
	185	count == sizeof(unsigned int))
	186	ret = put_user(data, (unsigned int __user *)buf) ?:
	187	sizeof(unsigned int);
	188	else
	189	ret = put_user(data, (unsigned long __user *)buf) ?:
	190	sizeof(unsigned long);
e824290e AZ	191	}
	192	return ret;
	193	}
	194
	195	static unsigned int rtc_dev_poll(struct file file, poll_table wait)
	196	{
	197	struct rtc_device *rtc = to_rtc_device(file->private_data);
	198	unsigned long data;
	199
	200	poll_wait(file, &rtc->irq_queue, wait);
	201
	202	data = rtc->irq_data;
	203
	204	return (data != 0) ? (POLLIN \| POLLRDNORM) : 0;
	205	}
	206
	207	static int rtc_dev_ioctl(struct inode inode, struct file file,
	208	unsigned int cmd, unsigned long arg)
	209	{
	210	int err = 0;
	211	struct class_device *class_dev = file->private_data;
	212	struct rtc_device *rtc = to_rtc_device(class_dev);
ff8371ac	213	const struct rtc_class_ops *ops = rtc->ops;
e824290e AZ	214	struct rtc_time tm;
	215	struct rtc_wkalrm alarm;
	216	void __user uarg = (void __user ) arg;
	217
110d693d AZ	218	/* check that the calles has appropriate permissions
	219	* for certain ioctls. doing this check here is useful
	220	* to avoid duplicate code in each driver.
	221	*/
	222	switch (cmd) {
	223	case RTC_EPOCH_SET:
	224	case RTC_SET_TIME:
	225	if (!capable(CAP_SYS_TIME))
	226	return -EACCES;
	227	break;
	228
	229	case RTC_IRQP_SET:
	230	if (arg > rtc->max_user_freq && !capable(CAP_SYS_RESOURCE))
	231	return -EACCES;
	232	break;
	233
	234	case RTC_PIE_ON:
	235	if (!capable(CAP_SYS_RESOURCE))
	236	return -EACCES;
	237	break;
	238	}
	239
e824290e AZ	240	/* avoid conflicting IRQ users */
	241	if (cmd == RTC_PIE_ON \|\| cmd == RTC_PIE_OFF \|\| cmd == RTC_IRQP_SET) {
	242	spin_lock(&rtc->irq_task_lock);
	243	if (rtc->irq_task)
	244	err = -EBUSY;
	245	spin_unlock(&rtc->irq_task_lock);
	246
	247	if (err < 0)
	248	return err;
	249	}
	250
	251	/* try the driver's ioctl interface */
	252	if (ops->ioctl) {
	253	err = ops->ioctl(class_dev->dev, cmd, arg);
b3969e58	254	if (err != -ENOIOCTLCMD)
e824290e AZ	255	return err;
	256	}
	257
	258	/* if the driver does not provide the ioctl interface
	259	* or if that particular ioctl was not implemented
b3969e58	260	* (-ENOIOCTLCMD), we will try to emulate here.
e824290e AZ	261	*/
	262
	263	switch (cmd) {
	264	case RTC_ALM_READ:
	265	err = rtc_read_alarm(class_dev, &alarm);
	266	if (err < 0)
	267	return err;
	268
	269	if (copy_to_user(uarg, &alarm.time, sizeof(tm)))
	270	return -EFAULT;
	271	break;
	272
	273	case RTC_ALM_SET:
	274	if (copy_from_user(&alarm.time, uarg, sizeof(tm)))
	275	return -EFAULT;
	276
	277	alarm.enabled = 0;
	278	alarm.pending = 0;
	279	alarm.time.tm_mday = -1;
	280	alarm.time.tm_mon = -1;
	281	alarm.time.tm_year = -1;
	282	alarm.time.tm_wday = -1;
	283	alarm.time.tm_yday = -1;
	284	alarm.time.tm_isdst = -1;
	285	err = rtc_set_alarm(class_dev, &alarm);
	286	break;
	287
	288	case RTC_RD_TIME:
	289	err = rtc_read_time(class_dev, &tm);
	290	if (err < 0)
	291	return err;
	292
	293	if (copy_to_user(uarg, &tm, sizeof(tm)))
	294	return -EFAULT;
	295	break;
	296
	297	case RTC_SET_TIME:
e824290e AZ	298	if (copy_from_user(&tm, uarg, sizeof(tm)))
	299	return -EFAULT;
	300
	301	err = rtc_set_time(class_dev, &tm);
	302	break;
	303	#if 0
	304	case RTC_EPOCH_SET:
	305	#ifndef rtc_epoch
	306	/*
	307	* There were no RTC clocks before 1900.
	308	*/
	309	if (arg < 1900) {
	310	err = -EINVAL;
	311	break;
	312	}
e824290e AZ	313	rtc_epoch = arg;
	314	err = 0;
	315	#endif
	316	break;
	317
	318	case RTC_EPOCH_READ:
	319	err = put_user(rtc_epoch, (unsigned long __user *)uarg);
	320	break;
	321	#endif
	322	case RTC_WKALM_SET:
	323	if (copy_from_user(&alarm, uarg, sizeof(alarm)))
	324	return -EFAULT;
	325
	326	err = rtc_set_alarm(class_dev, &alarm);
	327	break;
	328
	329	case RTC_WKALM_RD:
	330	err = rtc_read_alarm(class_dev, &alarm);
	331	if (err < 0)
	332	return err;
	333
	334	if (copy_to_user(uarg, &alarm, sizeof(alarm)))
	335	return -EFAULT;
	336	break;
	337
655066c3 AN	338	#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
	339	case RTC_UIE_OFF:
	340	clear_uie(rtc);
	341	return 0;
	342
	343	case RTC_UIE_ON:
	344	return set_uie(rtc);
	345	#endif
e824290e	346	default:
b3969e58	347	err = -ENOTTY;
e824290e AZ	348	break;
	349	}
	350
	351	return err;
	352	}
	353
	354	static int rtc_dev_release(struct inode inode, struct file file)
	355	{
	356	struct rtc_device *rtc = to_rtc_device(file->private_data);
	357
655066c3 AN	358	#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
	359	clear_uie(rtc);
	360	#endif
e824290e AZ	361	if (rtc->ops->release)
	362	rtc->ops->release(rtc->class_dev.dev);
	363
	364	mutex_unlock(&rtc->char_lock);
	365	return 0;
	366	}
	367
	368	static int rtc_dev_fasync(int fd, struct file *file, int on)
	369	{
	370	struct rtc_device *rtc = to_rtc_device(file->private_data);
	371	return fasync_helper(fd, file, on, &rtc->async_queue);
	372	}
	373
	374	static struct file_operations rtc_dev_fops = {
	375	.owner = THIS_MODULE,
	376	.llseek = no_llseek,
	377	.read = rtc_dev_read,
	378	.poll = rtc_dev_poll,
	379	.ioctl = rtc_dev_ioctl,
	380	.open = rtc_dev_open,
	381	.release = rtc_dev_release,
	382	.fasync = rtc_dev_fasync,
	383	};
	384
	385	/* insertion/removal hooks */
	386
	387	static int rtc_dev_add_device(struct class_device *class_dev,
	388	struct class_interface *class_intf)
	389	{
	390	int err = 0;
	391	struct rtc_device *rtc = to_rtc_device(class_dev);
	392
	393	if (rtc->id >= RTC_DEV_MAX) {
	394	dev_err(class_dev->dev, "too many RTCs\n");
	395	return -EINVAL;
	396	}
	397
	398	mutex_init(&rtc->char_lock);
	399	spin_lock_init(&rtc->irq_lock);
	400	init_waitqueue_head(&rtc->irq_queue);
655066c3	401	#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
c4028958	402	INIT_WORK(&rtc->uie_task, rtc_uie_task);
655066c3 AN	403	setup_timer(&rtc->uie_timer, rtc_uie_timer, (unsigned long)rtc);
655066c3 AN	404	#endif
e824290e AZ	405
	406	cdev_init(&rtc->char_dev, &rtc_dev_fops);
	407	rtc->char_dev.owner = rtc->owner;
	408
	409	if (cdev_add(&rtc->char_dev, MKDEV(MAJOR(rtc_devt), rtc->id), 1)) {
e824290e AZ	410	dev_err(class_dev->dev,
	411	"failed to add char device %d:%d\n",
	412	MAJOR(rtc_devt), rtc->id);
	413	return -ENODEV;
	414	}
	415
	416	rtc->rtc_dev = class_device_create(rtc_dev_class, NULL,
	417	MKDEV(MAJOR(rtc_devt), rtc->id),
	418	class_dev->dev, "rtc%d", rtc->id);
	419	if (IS_ERR(rtc->rtc_dev)) {
	420	dev_err(class_dev->dev, "cannot create rtc_dev device\n");
	421	err = PTR_ERR(rtc->rtc_dev);
	422	goto err_cdev_del;
	423	}
	424
	425	dev_info(class_dev->dev, "rtc intf: dev (%d:%d)\n",
	426	MAJOR(rtc->rtc_dev->devt),
	427	MINOR(rtc->rtc_dev->devt));
	428
	429	return 0;
	430
	431	err_cdev_del:
	432
	433	cdev_del(&rtc->char_dev);
	434	return err;
	435	}
	436
	437	static void rtc_dev_remove_device(struct class_device *class_dev,
	438	struct class_interface *class_intf)
	439	{
	440	struct rtc_device *rtc = to_rtc_device(class_dev);
	441
	442	if (rtc->rtc_dev) {
	443	dev_dbg(class_dev->dev, "removing char %d:%d\n",
	444	MAJOR(rtc->rtc_dev->devt),
	445	MINOR(rtc->rtc_dev->devt));
	446
	447	class_device_unregister(rtc->rtc_dev);
	448	cdev_del(&rtc->char_dev);
	449	}
	450	}
	451
	452	/* interface registration */
	453
	454	static struct class_interface rtc_dev_interface = {
	455	.add = &rtc_dev_add_device,
	456	.remove = &rtc_dev_remove_device,
	457	};
	458
	459	static int __init rtc_dev_init(void)
	460	{
	461	int err;
	462
	463	rtc_dev_class = class_create(THIS_MODULE, "rtc-dev");
	464	if (IS_ERR(rtc_dev_class))
	465	return PTR_ERR(rtc_dev_class);
	466
	467	err = alloc_chrdev_region(&rtc_devt, 0, RTC_DEV_MAX, "rtc");
	468	if (err < 0) {
	469	printk(KERN_ERR "%s: failed to allocate char dev region\n",
	470	__FILE__);
	471	goto err_destroy_class;
	472	}
	473
474	err = rtc_interface_register(&rtc_dev_interface);
475	if (err < 0) {
476	printk(KERN_ERR "%s: failed to register the interface\n",
477	__FILE__);
478	goto err_unregister_chrdev;
479	}
480
481	return 0;
482
483	err_unregister_chrdev:
484	unregister_chrdev_region(rtc_devt, RTC_DEV_MAX);
485
486	err_destroy_class:
487	class_destroy(rtc_dev_class);
488
489	return err;
490	}
491
492	static void __exit rtc_dev_exit(void)
493	{
494	class_interface_unregister(&rtc_dev_interface);
495	class_destroy(rtc_dev_class);
496	unregister_chrdev_region(rtc_devt, RTC_DEV_MAX);
497	}
498
818a8674	499	subsys_initcall(rtc_dev_init);
e824290e AZ	500	module_exit(rtc_dev_exit);
	501
	502	MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
	503	MODULE_DESCRIPTION("RTC class dev interface");
	504	MODULE_LICENSE("GPL");