[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>

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(void *data)
{
	struct rtc_device *rtc = data;
	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 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 (!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;

	case RTC_IRQP_READ:
		if (ops->irq_set_freq)
			err = put_user(rtc->irq_freq, (unsigned long *) arg);
		break;

	case RTC_IRQP_SET:
		if (ops->irq_set_freq)
			err = rtc_irq_set_freq(class_dev, rtc->irq_task, arg);
		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, rtc);
	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	*/
	56	static void rtc_uie_task(void *data)
	57	{
	58	struct rtc_device *rtc = data;
	59	struct rtc_time tm;
	60	int num = 0;
	61	int err;
	62
	63	err = rtc_read_time(&rtc->class_dev, &tm);
	64	spin_lock_irq(&rtc->irq_lock);
	65	if (rtc->stop_uie_polling \|\| err) {
	66	rtc->uie_task_active = 0;
	67	} else if (rtc->oldsecs != tm.tm_sec) {
	68	num = (tm.tm_sec + 60 - rtc->oldsecs) % 60;
	69	rtc->oldsecs = tm.tm_sec;
	70	rtc->uie_timer.expires = jiffies + HZ - (HZ/10);
	71	rtc->uie_timer_active = 1;
	72	rtc->uie_task_active = 0;
	73	add_timer(&rtc->uie_timer);
	74	} else if (schedule_work(&rtc->uie_task) == 0) {
	75	rtc->uie_task_active = 0;
	76	}
	77	spin_unlock_irq(&rtc->irq_lock);
	78	if (num)
	79	rtc_update_irq(&rtc->class_dev, num, RTC_UF \| RTC_IRQF);
	80	}
	81
	82	static void rtc_uie_timer(unsigned long data)
	83	{
	84	struct rtc_device rtc = (struct rtc_device )data;
	85	unsigned long flags;
	86
	87	spin_lock_irqsave(&rtc->irq_lock, flags);
	88	rtc->uie_timer_active = 0;
	89	rtc->uie_task_active = 1;
	90	if ((schedule_work(&rtc->uie_task) == 0))
	91	rtc->uie_task_active = 0;
	92	spin_unlock_irqrestore(&rtc->irq_lock, flags);
	93	}
	94
	95	static void clear_uie(struct rtc_device *rtc)
	96	{
	97	spin_lock_irq(&rtc->irq_lock);
	98	if (rtc->irq_active) {
	99	rtc->stop_uie_polling = 1;
	100	if (rtc->uie_timer_active) {
	101	spin_unlock_irq(&rtc->irq_lock);
	102	del_timer_sync(&rtc->uie_timer);
	103	spin_lock_irq(&rtc->irq_lock);
	104	rtc->uie_timer_active = 0;
	105	}
	106	if (rtc->uie_task_active) {
	107	spin_unlock_irq(&rtc->irq_lock);
	108	flush_scheduled_work();
	109	spin_lock_irq(&rtc->irq_lock);
	110	}
	111	rtc->irq_active = 0;
	112	}
	113	spin_unlock_irq(&rtc->irq_lock);
	114	}
115
116	static int set_uie(struct rtc_device *rtc)
117	{
118	struct rtc_time tm;
119	int err;
120
121	err = rtc_read_time(&rtc->class_dev, &tm);
122	if (err)
123	return err;
124	spin_lock_irq(&rtc->irq_lock);
125	if (!rtc->irq_active) {
126	rtc->irq_active = 1;
127	rtc->stop_uie_polling = 0;
128	rtc->oldsecs = tm.tm_sec;
129	rtc->uie_task_active = 1;
130	if (schedule_work(&rtc->uie_task) == 0)
131	rtc->uie_task_active = 0;
132	}
133	rtc->irq_data = 0;
134	spin_unlock_irq(&rtc->irq_lock);
135	return 0;
136	}
137	#endif /* CONFIG_RTC_INTF_DEV_UIE_EMUL */
e824290e AZ	138
	139	static ssize_t
	140	rtc_dev_read(struct file file, char __user buf, size_t count, loff_t *ppos)
	141	{
	142	struct rtc_device *rtc = to_rtc_device(file->private_data);
	143
	144	DECLARE_WAITQUEUE(wait, current);
	145	unsigned long data;
	146	ssize_t ret;
	147
3418ff76	148	if (count != sizeof(unsigned int) && count < sizeof(unsigned long))
e824290e AZ	149	return -EINVAL;
	150
	151	add_wait_queue(&rtc->irq_queue, &wait);
	152	do {
	153	__set_current_state(TASK_INTERRUPTIBLE);
	154
	155	spin_lock_irq(&rtc->irq_lock);
	156	data = rtc->irq_data;
	157	rtc->irq_data = 0;
	158	spin_unlock_irq(&rtc->irq_lock);
	159
	160	if (data != 0) {
	161	ret = 0;
	162	break;
	163	}
	164	if (file->f_flags & O_NONBLOCK) {
	165	ret = -EAGAIN;
	166	break;
	167	}
	168	if (signal_pending(current)) {
	169	ret = -ERESTARTSYS;
	170	break;
	171	}
	172	schedule();
	173	} while (1);
	174	set_current_state(TASK_RUNNING);
	175	remove_wait_queue(&rtc->irq_queue, &wait);
	176
	177	if (ret == 0) {
	178	/* Check for any data updates */
	179	if (rtc->ops->read_callback)
3418ff76 AN	180	data = rtc->ops->read_callback(rtc->class_dev.dev,
	181	data);
	182
	183	if (sizeof(int) != sizeof(long) &&
	184	count == sizeof(unsigned int))
	185	ret = put_user(data, (unsigned int __user *)buf) ?:
	186	sizeof(unsigned int);
	187	else
	188	ret = put_user(data, (unsigned long __user *)buf) ?:
	189	sizeof(unsigned long);
e824290e AZ	190	}
	191	return ret;
	192	}
	193
	194	static unsigned int rtc_dev_poll(struct file file, poll_table wait)
	195	{
	196	struct rtc_device *rtc = to_rtc_device(file->private_data);
	197	unsigned long data;
	198
	199	poll_wait(file, &rtc->irq_queue, wait);
	200
	201	data = rtc->irq_data;
	202
	203	return (data != 0) ? (POLLIN \| POLLRDNORM) : 0;
	204	}
	205
	206	static int rtc_dev_ioctl(struct inode inode, struct file file,
	207	unsigned int cmd, unsigned long arg)
	208	{
	209	int err = 0;
	210	struct class_device *class_dev = file->private_data;
	211	struct rtc_device *rtc = to_rtc_device(class_dev);
ff8371ac	212	const struct rtc_class_ops *ops = rtc->ops;
e824290e AZ	213	struct rtc_time tm;
	214	struct rtc_wkalrm alarm;
	215	void __user uarg = (void __user ) arg;
	216
2601a464	217	/* check that the calling task has appropriate permissions
110d693d AZ	218	* for certain ioctls. doing this check here is useful
	219	* to avoid duplicate code in each driver.
	220	*/
	221	switch (cmd) {
	222	case RTC_EPOCH_SET:
	223	case RTC_SET_TIME:
	224	if (!capable(CAP_SYS_TIME))
	225	return -EACCES;
	226	break;
	227
	228	case RTC_IRQP_SET:
	229	if (arg > rtc->max_user_freq && !capable(CAP_SYS_RESOURCE))
	230	return -EACCES;
	231	break;
	232
	233	case RTC_PIE_ON:
	234	if (!capable(CAP_SYS_RESOURCE))
	235	return -EACCES;
	236	break;
	237	}
	238
e824290e AZ	239	/* avoid conflicting IRQ users */
	240	if (cmd == RTC_PIE_ON \|\| cmd == RTC_PIE_OFF \|\| cmd == RTC_IRQP_SET) {
	241	spin_lock(&rtc->irq_task_lock);
	242	if (rtc->irq_task)
	243	err = -EBUSY;
	244	spin_unlock(&rtc->irq_task_lock);
	245
	246	if (err < 0)
	247	return err;
	248	}
	249
	250	/* try the driver's ioctl interface */
	251	if (ops->ioctl) {
	252	err = ops->ioctl(class_dev->dev, cmd, arg);
b3969e58	253	if (err != -ENOIOCTLCMD)
e824290e AZ	254	return err;
	255	}
	256
	257	/* if the driver does not provide the ioctl interface
	258	* or if that particular ioctl was not implemented
b3969e58	259	* (-ENOIOCTLCMD), we will try to emulate here.
e824290e AZ	260	*/
	261
	262	switch (cmd) {
	263	case RTC_ALM_READ:
	264	err = rtc_read_alarm(class_dev, &alarm);
	265	if (err < 0)
	266	return err;
	267
	268	if (copy_to_user(uarg, &alarm.time, sizeof(tm)))
	269	return -EFAULT;
	270	break;
	271
	272	case RTC_ALM_SET:
	273	if (copy_from_user(&alarm.time, uarg, sizeof(tm)))
	274	return -EFAULT;
	275
	276	alarm.enabled = 0;
	277	alarm.pending = 0;
	278	alarm.time.tm_mday = -1;
	279	alarm.time.tm_mon = -1;
	280	alarm.time.tm_year = -1;
	281	alarm.time.tm_wday = -1;
	282	alarm.time.tm_yday = -1;
	283	alarm.time.tm_isdst = -1;
	284	err = rtc_set_alarm(class_dev, &alarm);
	285	break;
	286
	287	case RTC_RD_TIME:
	288	err = rtc_read_time(class_dev, &tm);
	289	if (err < 0)
	290	return err;
	291
	292	if (copy_to_user(uarg, &tm, sizeof(tm)))
	293	return -EFAULT;
	294	break;
	295
	296	case RTC_SET_TIME:
e824290e AZ	297	if (copy_from_user(&tm, uarg, sizeof(tm)))
	298	return -EFAULT;
	299
	300	err = rtc_set_time(class_dev, &tm);
	301	break;
2601a464 DB	302
	303	case RTC_IRQP_READ:
	304	if (ops->irq_set_freq)
	305	err = put_user(rtc->irq_freq, (unsigned long *) arg);
	306	break;
	307
	308	case RTC_IRQP_SET:
	309	if (ops->irq_set_freq)
	310	err = rtc_irq_set_freq(class_dev, rtc->irq_task, arg);
	311	break;
	312
e824290e AZ	313	#if 0
	314	case RTC_EPOCH_SET:
	315	#ifndef rtc_epoch
	316	/*
	317	* There were no RTC clocks before 1900.
	318	*/
	319	if (arg < 1900) {
	320	err = -EINVAL;
	321	break;
	322	}
e824290e AZ	323	rtc_epoch = arg;
	324	err = 0;
	325	#endif
	326	break;
	327
	328	case RTC_EPOCH_READ:
	329	err = put_user(rtc_epoch, (unsigned long __user *)uarg);
	330	break;
	331	#endif
	332	case RTC_WKALM_SET:
	333	if (copy_from_user(&alarm, uarg, sizeof(alarm)))
	334	return -EFAULT;
	335
	336	err = rtc_set_alarm(class_dev, &alarm);
	337	break;
	338
	339	case RTC_WKALM_RD:
	340	err = rtc_read_alarm(class_dev, &alarm);
	341	if (err < 0)
	342	return err;
	343
	344	if (copy_to_user(uarg, &alarm, sizeof(alarm)))
	345	return -EFAULT;
	346	break;
	347
655066c3 AN	348	#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
	349	case RTC_UIE_OFF:
	350	clear_uie(rtc);
	351	return 0;
	352
	353	case RTC_UIE_ON:
	354	return set_uie(rtc);
	355	#endif
e824290e	356	default:
b3969e58	357	err = -ENOTTY;
e824290e AZ	358	break;
	359	}
	360
	361	return err;
	362	}
	363
	364	static int rtc_dev_release(struct inode inode, struct file file)
	365	{
	366	struct rtc_device *rtc = to_rtc_device(file->private_data);
	367
655066c3 AN	368	#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
	369	clear_uie(rtc);
	370	#endif
e824290e AZ	371	if (rtc->ops->release)
	372	rtc->ops->release(rtc->class_dev.dev);
	373
	374	mutex_unlock(&rtc->char_lock);
	375	return 0;
	376	}
	377
	378	static int rtc_dev_fasync(int fd, struct file *file, int on)
	379	{
	380	struct rtc_device *rtc = to_rtc_device(file->private_data);
	381	return fasync_helper(fd, file, on, &rtc->async_queue);
	382	}
	383
	384	static struct file_operations rtc_dev_fops = {
	385	.owner = THIS_MODULE,
	386	.llseek = no_llseek,
	387	.read = rtc_dev_read,
	388	.poll = rtc_dev_poll,
	389	.ioctl = rtc_dev_ioctl,
	390	.open = rtc_dev_open,
	391	.release = rtc_dev_release,
	392	.fasync = rtc_dev_fasync,
	393	};
	394
	395	/* insertion/removal hooks */
	396
	397	static int rtc_dev_add_device(struct class_device *class_dev,
	398	struct class_interface *class_intf)
	399	{
	400	int err = 0;
	401	struct rtc_device *rtc = to_rtc_device(class_dev);
	402
	403	if (rtc->id >= RTC_DEV_MAX) {
	404	dev_err(class_dev->dev, "too many RTCs\n");
	405	return -EINVAL;
	406	}
	407
	408	mutex_init(&rtc->char_lock);
	409	spin_lock_init(&rtc->irq_lock);
	410	init_waitqueue_head(&rtc->irq_queue);
655066c3 AN	411	#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
	412	INIT_WORK(&rtc->uie_task, rtc_uie_task, rtc);
	413	setup_timer(&rtc->uie_timer, rtc_uie_timer, (unsigned long)rtc);
	414	#endif
e824290e AZ	415
	416	cdev_init(&rtc->char_dev, &rtc_dev_fops);
	417	rtc->char_dev.owner = rtc->owner;
	418
	419	if (cdev_add(&rtc->char_dev, MKDEV(MAJOR(rtc_devt), rtc->id), 1)) {
e824290e AZ	420	dev_err(class_dev->dev,
	421	"failed to add char device %d:%d\n",
	422	MAJOR(rtc_devt), rtc->id);
	423	return -ENODEV;
	424	}
	425
	426	rtc->rtc_dev = class_device_create(rtc_dev_class, NULL,
	427	MKDEV(MAJOR(rtc_devt), rtc->id),
	428	class_dev->dev, "rtc%d", rtc->id);
	429	if (IS_ERR(rtc->rtc_dev)) {
	430	dev_err(class_dev->dev, "cannot create rtc_dev device\n");
	431	err = PTR_ERR(rtc->rtc_dev);
	432	goto err_cdev_del;
	433	}
	434
	435	dev_info(class_dev->dev, "rtc intf: dev (%d:%d)\n",
	436	MAJOR(rtc->rtc_dev->devt),
	437	MINOR(rtc->rtc_dev->devt));
	438
	439	return 0;
	440
	441	err_cdev_del:
	442
	443	cdev_del(&rtc->char_dev);
	444	return err;
	445	}
	446
	447	static void rtc_dev_remove_device(struct class_device *class_dev,
	448	struct class_interface *class_intf)
	449	{
	450	struct rtc_device *rtc = to_rtc_device(class_dev);
	451
	452	if (rtc->rtc_dev) {
	453	dev_dbg(class_dev->dev, "removing char %d:%d\n",
	454	MAJOR(rtc->rtc_dev->devt),
	455	MINOR(rtc->rtc_dev->devt));
	456
	457	class_device_unregister(rtc->rtc_dev);
	458	cdev_del(&rtc->char_dev);
	459	}
	460	}
	461
	462	/* interface registration */
	463
	464	static struct class_interface rtc_dev_interface = {
	465	.add = &rtc_dev_add_device,
	466	.remove = &rtc_dev_remove_device,
	467	};
	468
	469	static int __init rtc_dev_init(void)
	470	{
	471	int err;
	472
	473	rtc_dev_class = class_create(THIS_MODULE, "rtc-dev");
	474	if (IS_ERR(rtc_dev_class))
	475	return PTR_ERR(rtc_dev_class);
	476
	477	err = alloc_chrdev_region(&rtc_devt, 0, RTC_DEV_MAX, "rtc");
	478	if (err < 0) {
	479	printk(KERN_ERR "%s: failed to allocate char dev region\n",
	480	__FILE__);
	481	goto err_destroy_class;
	482	}
	483
484	err = rtc_interface_register(&rtc_dev_interface);
485	if (err < 0) {
486	printk(KERN_ERR "%s: failed to register the interface\n",
487	__FILE__);
488	goto err_unregister_chrdev;
489	}
490
491	return 0;
492
493	err_unregister_chrdev:
494	unregister_chrdev_region(rtc_devt, RTC_DEV_MAX);
495
496	err_destroy_class:
497	class_destroy(rtc_dev_class);
498
499	return err;
500	}
501
502	static void __exit rtc_dev_exit(void)
503	{
504	class_interface_unregister(&rtc_dev_interface);
505	class_destroy(rtc_dev_class);
506	unregister_chrdev_region(rtc_devt, RTC_DEV_MAX);
507	}
508
818a8674	509	subsys_initcall(rtc_dev_init);
e824290e AZ	510	module_exit(rtc_dev_exit);
	511
	512	MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
	513	MODULE_DESCRIPTION("RTC class dev interface");
	514	MODULE_LICENSE("GPL");