[deliverable/linux.git] / drivers / rtc / class.c

/*
 * RTC subsystem, base class
 *
 * Copyright (C) 2005 Tower Technologies
 * Author: Alessandro Zummo <a.zummo@towertech.it>
 *
 * class skeleton from drivers/hwmon/hwmon.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.
*/

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/of.h>
#include <linux/rtc.h>
#include <linux/kdev_t.h>
#include <linux/idr.h>
#include <linux/slab.h>
#include <linux/workqueue.h>

#include "rtc-core.h"


static DEFINE_IDA(rtc_ida);
struct class *rtc_class;

static void rtc_device_release(struct device *dev)
{
	struct rtc_device *rtc = to_rtc_device(dev);
	ida_simple_remove(&rtc_ida, rtc->id);
	kfree(rtc);
}

#ifdef CONFIG_RTC_HCTOSYS_DEVICE
/* Result of the last RTC to system clock attempt. */
int rtc_hctosys_ret = -ENODEV;
#endif

#if defined(CONFIG_PM_SLEEP) && defined(CONFIG_RTC_HCTOSYS_DEVICE)
/*
 * On suspend(), measure the delta between one RTC and the
 * system's wall clock; restore it on resume().
 */

static struct timespec old_rtc, old_system, old_delta;


static int rtc_suspend(struct device *dev)
{
	struct rtc_device	*rtc = to_rtc_device(dev);
	struct rtc_time		tm;
	struct timespec		delta, delta_delta;

	if (has_persistent_clock())
		return 0;

	if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)
		return 0;

	/* snapshot the current RTC and system time at suspend*/
	rtc_read_time(rtc, &tm);
	getnstimeofday(&old_system);
	rtc_tm_to_time(&tm, &old_rtc.tv_sec);


	/*
	 * To avoid drift caused by repeated suspend/resumes,
	 * which each can add ~1 second drift error,
	 * try to compensate so the difference in system time
	 * and rtc time stays close to constant.
	 */
	delta = timespec_sub(old_system, old_rtc);
	delta_delta = timespec_sub(delta, old_delta);
	if (delta_delta.tv_sec < -2 || delta_delta.tv_sec >= 2) {
		/*
		 * if delta_delta is too large, assume time correction
		 * has occured and set old_delta to the current delta.
		 */
		old_delta = delta;
	} else {
		/* Otherwise try to adjust old_system to compensate */
		old_system = timespec_sub(old_system, delta_delta);
	}

	return 0;
}

static int rtc_resume(struct device *dev)
{
	struct rtc_device	*rtc = to_rtc_device(dev);
	struct rtc_time		tm;
	struct timespec		new_system, new_rtc;
	struct timespec		sleep_time;

	if (has_persistent_clock())
		return 0;

	rtc_hctosys_ret = -ENODEV;
	if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)
		return 0;

	/* snapshot the current rtc and system time at resume */
	getnstimeofday(&new_system);
	rtc_read_time(rtc, &tm);
	if (rtc_valid_tm(&tm) != 0) {
		pr_debug("%s:  bogus resume time\n", dev_name(&rtc->dev));
		return 0;
	}
	rtc_tm_to_time(&tm, &new_rtc.tv_sec);
	new_rtc.tv_nsec = 0;

	if (new_rtc.tv_sec < old_rtc.tv_sec) {
		pr_debug("%s:  time travel!\n", dev_name(&rtc->dev));
		return 0;
	}

	/* calculate the RTC time delta (sleep time)*/
	sleep_time = timespec_sub(new_rtc, old_rtc);

	/*
	 * Since these RTC suspend/resume handlers are not called
	 * at the very end of suspend or the start of resume,
	 * some run-time may pass on either sides of the sleep time
	 * so subtract kernel run-time between rtc_suspend to rtc_resume
	 * to keep things accurate.
	 */
	sleep_time = timespec_sub(sleep_time,
			timespec_sub(new_system, old_system));

	if (sleep_time.tv_sec >= 0)
		timekeeping_inject_sleeptime(&sleep_time);
	rtc_hctosys_ret = 0;
	return 0;
}

static SIMPLE_DEV_PM_OPS(rtc_class_dev_pm_ops, rtc_suspend, rtc_resume);
#define RTC_CLASS_DEV_PM_OPS	(&rtc_class_dev_pm_ops)
#else
#define RTC_CLASS_DEV_PM_OPS	NULL
#endif


/**
 * rtc_device_register - register w/ RTC class
 * @dev: the device to register
 *
 * rtc_device_unregister() must be called when the class device is no
 * longer needed.
 *
 * Returns the pointer to the new struct class device.
 */
struct rtc_device *rtc_device_register(const char *name, struct device *dev,
					const struct rtc_class_ops *ops,
					struct module *owner)
{
	struct rtc_device *rtc;
	struct rtc_wkalrm alrm;
	int of_id = -1, id = -1, err;

	if (dev->of_node)
		of_id = of_alias_get_id(dev->of_node, "rtc");
	else if (dev->parent && dev->parent->of_node)
		of_id = of_alias_get_id(dev->parent->of_node, "rtc");

	if (of_id >= 0) {
		id = ida_simple_get(&rtc_ida, of_id, of_id + 1,
				    GFP_KERNEL);
		if (id < 0)
			dev_warn(dev, "/aliases ID %d not available\n",
				    of_id);
	}

	if (id < 0) {
		id = ida_simple_get(&rtc_ida, 0, 0, GFP_KERNEL);
		if (id < 0) {
			err = id;
			goto exit;
		}
	}

	rtc = kzalloc(sizeof(struct rtc_device), GFP_KERNEL);
	if (rtc == NULL) {
		err = -ENOMEM;
		goto exit_ida;
	}

	rtc->id = id;
	rtc->ops = ops;
	rtc->owner = owner;
	rtc->irq_freq = 1;
	rtc->max_user_freq = 64;
	rtc->dev.parent = dev;
	rtc->dev.class = rtc_class;
	rtc->dev.release = rtc_device_release;

	mutex_init(&rtc->ops_lock);
	spin_lock_init(&rtc->irq_lock);
	spin_lock_init(&rtc->irq_task_lock);
	init_waitqueue_head(&rtc->irq_queue);

	/* Init timerqueue */
	timerqueue_init_head(&rtc->timerqueue);
	INIT_WORK(&rtc->irqwork, rtc_timer_do_work);
	/* Init aie timer */
	rtc_timer_init(&rtc->aie_timer, rtc_aie_update_irq, (void *)rtc);
	/* Init uie timer */
	rtc_timer_init(&rtc->uie_rtctimer, rtc_uie_update_irq, (void *)rtc);
	/* Init pie timer */
	hrtimer_init(&rtc->pie_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
	rtc->pie_timer.function = rtc_pie_update_irq;
	rtc->pie_enabled = 0;

	/* Check to see if there is an ALARM already set in hw */
	err = __rtc_read_alarm(rtc, &alrm);

	if (!err && !rtc_valid_tm(&alrm.time))
		rtc_initialize_alarm(rtc, &alrm);

	strlcpy(rtc->name, name, RTC_DEVICE_NAME_SIZE);
	dev_set_name(&rtc->dev, "rtc%d", id);

	rtc_dev_prepare(rtc);

	err = device_register(&rtc->dev);
	if (err) {
		put_device(&rtc->dev);
		goto exit_kfree;
	}

	rtc_dev_add_device(rtc);
	rtc_sysfs_add_device(rtc);
	rtc_proc_add_device(rtc);

	dev_info(dev, "rtc core: registered %s as %s\n",
			rtc->name, dev_name(&rtc->dev));

	return rtc;

exit_kfree:
	kfree(rtc);

exit_ida:
	ida_simple_remove(&rtc_ida, id);

exit:
	dev_err(dev, "rtc core: unable to register %s, err = %d\n",
			name, err);
	return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(rtc_device_register);


/**
 * rtc_device_unregister - removes the previously registered RTC class device
 *
 * @rtc: the RTC class device to destroy
 */
void rtc_device_unregister(struct rtc_device *rtc)
{
	if (get_device(&rtc->dev) != NULL) {
		mutex_lock(&rtc->ops_lock);
		/* remove innards of this RTC, then disable it, before
		 * letting any rtc_class_open() users access it again
		 */
		rtc_sysfs_del_device(rtc);
		rtc_dev_del_device(rtc);
		rtc_proc_del_device(rtc);
		device_unregister(&rtc->dev);
		rtc->ops = NULL;
		mutex_unlock(&rtc->ops_lock);
		put_device(&rtc->dev);
	}
}
EXPORT_SYMBOL_GPL(rtc_device_unregister);

static void devm_rtc_device_release(struct device *dev, void *res)
{
	struct rtc_device *rtc = *(struct rtc_device **)res;

	rtc_device_unregister(rtc);
}

static int devm_rtc_device_match(struct device *dev, void *res, void *data)
{
	struct rtc **r = res;

	return *r == data;
}

/**
 * devm_rtc_device_register - resource managed rtc_device_register()
 * @dev: the device to register
 * @name: the name of the device
 * @ops: the rtc operations structure
 * @owner: the module owner
 *
 * @return a struct rtc on success, or an ERR_PTR on error
 *
 * Managed rtc_device_register(). The rtc_device returned from this function
 * are automatically freed on driver detach. See rtc_device_register()
 * for more information.
 */

struct rtc_device *devm_rtc_device_register(struct device *dev,
					const char *name,
					const struct rtc_class_ops *ops,
					struct module *owner)
{
	struct rtc_device **ptr, *rtc;

	ptr = devres_alloc(devm_rtc_device_release, sizeof(*ptr), GFP_KERNEL);
	if (!ptr)
		return ERR_PTR(-ENOMEM);

	rtc = rtc_device_register(name, dev, ops, owner);
	if (!IS_ERR(rtc)) {
		*ptr = rtc;
		devres_add(dev, ptr);
	} else {
		devres_free(ptr);
	}

	return rtc;
}
EXPORT_SYMBOL_GPL(devm_rtc_device_register);

/**
 * devm_rtc_device_unregister - resource managed devm_rtc_device_unregister()
 * @dev: the device to unregister
 * @rtc: the RTC class device to unregister
 *
 * Deallocated a rtc allocated with devm_rtc_device_register(). Normally this
 * function will not need to be called and the resource management code will
 * ensure that the resource is freed.
 */
void devm_rtc_device_unregister(struct device *dev, struct rtc_device *rtc)
{
	int rc;

	rc = devres_release(dev, devm_rtc_device_release,
				devm_rtc_device_match, rtc);
	WARN_ON(rc);
}
EXPORT_SYMBOL_GPL(devm_rtc_device_unregister);

static int __init rtc_init(void)
{
	rtc_class = class_create(THIS_MODULE, "rtc");
	if (IS_ERR(rtc_class)) {
		pr_err("couldn't create class\n");
		return PTR_ERR(rtc_class);
	}
	rtc_class->pm = RTC_CLASS_DEV_PM_OPS;
	rtc_dev_init();
	rtc_sysfs_init(rtc_class);
	return 0;
}

static void __exit rtc_exit(void)
{
	rtc_dev_exit();
	class_destroy(rtc_class);
	ida_destroy(&rtc_ida);
}

subsys_initcall(rtc_init);
module_exit(rtc_exit);

MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
MODULE_DESCRIPTION("RTC class support");
MODULE_LICENSE("GPL");
Commit	Line	Data
0c86edc0 AZ	1	/*
	2	* RTC subsystem, base class
	3	*
	4	* Copyright (C) 2005 Tower Technologies
	5	* Author: Alessandro Zummo <a.zummo@towertech.it>
	6	*
	7	* class skeleton from drivers/hwmon/hwmon.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
c100a5e0 JH	14	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
c100a5e0 JH	15
0c86edc0	16	#include <linux/module.h>
9d2b7e53	17	#include <linux/of.h>
0c86edc0 AZ	18	#include <linux/rtc.h>
	19	#include <linux/kdev_t.h>
	20	#include <linux/idr.h>
5a0e3ad6	21	#include <linux/slab.h>
6610e089	22	#include <linux/workqueue.h>
0c86edc0	23
5726fb20 DB	24	#include "rtc-core.h"
	25
	26
6d03d06d	27	static DEFINE_IDA(rtc_ida);
0c86edc0 AZ	28	struct class *rtc_class;
0c86edc0 AZ	29
cd966209	30	static void rtc_device_release(struct device *dev)
0c86edc0	31	{
cd966209	32	struct rtc_device *rtc = to_rtc_device(dev);
6d03d06d	33	ida_simple_remove(&rtc_ida, rtc->id);
0c86edc0 AZ	34	kfree(rtc);
	35	}
	36
4c24e29e DF	37	#ifdef CONFIG_RTC_HCTOSYS_DEVICE
	38	/* Result of the last RTC to system clock attempt. */
	39	int rtc_hctosys_ret = -ENODEV;
	40	#endif
7ca1d488	41
92e7f04a	42	#if defined(CONFIG_PM_SLEEP) && defined(CONFIG_RTC_HCTOSYS_DEVICE)
7ca1d488 DB	43	/*
	44	* On suspend(), measure the delta between one RTC and the
	45	* system's wall clock; restore it on resume().
	46	*/
	47
3dcad5ff JS	48	static struct timespec old_rtc, old_system, old_delta;
3dcad5ff JS	49
7ca1d488	50
92e7f04a	51	static int rtc_suspend(struct device *dev)
7ca1d488 DB	52	{
	53	struct rtc_device *rtc = to_rtc_device(dev);
	54	struct rtc_time tm;
3dcad5ff	55	struct timespec delta, delta_delta;
9ecf37eb FT	56
	57	if (has_persistent_clock())
	58	return 0;
	59
d4afc76c	60	if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)
7ca1d488 DB	61	return 0;
7ca1d488 DB	62
3dcad5ff	63	/* snapshot the current RTC and system time at suspend*/
7ca1d488	64	rtc_read_time(rtc, &tm);
3dcad5ff JS	65	getnstimeofday(&old_system);
	66	rtc_tm_to_time(&tm, &old_rtc.tv_sec);
	67
	68
	69	/*
	70	* To avoid drift caused by repeated suspend/resumes,
	71	* which each can add ~1 second drift error,
	72	* try to compensate so the difference in system time
	73	* and rtc time stays close to constant.
	74	*/
	75	delta = timespec_sub(old_system, old_rtc);
	76	delta_delta = timespec_sub(delta, old_delta);
6a8943d9	77	if (delta_delta.tv_sec < -2 \|\| delta_delta.tv_sec >= 2) {
3dcad5ff JS	78	/*
	79	* if delta_delta is too large, assume time correction
	80	* has occured and set old_delta to the current delta.
	81	*/
	82	old_delta = delta;
	83	} else {
	84	/* Otherwise try to adjust old_system to compensate */
	85	old_system = timespec_sub(old_system, delta_delta);
	86	}
7ca1d488	87
7ca1d488 DB	88	return 0;
	89	}
	90
	91	static int rtc_resume(struct device *dev)
	92	{
	93	struct rtc_device *rtc = to_rtc_device(dev);
	94	struct rtc_time tm;
3dcad5ff JS	95	struct timespec new_system, new_rtc;
3dcad5ff JS	96	struct timespec sleep_time;
7ca1d488	97
9ecf37eb FT	98	if (has_persistent_clock())
	99	return 0;
	100
4c24e29e	101	rtc_hctosys_ret = -ENODEV;
d4afc76c	102	if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)
7ca1d488 DB	103	return 0;
7ca1d488 DB	104
3dcad5ff JS	105	/* snapshot the current rtc and system time at resume */
3dcad5ff JS	106	getnstimeofday(&new_system);
7ca1d488 DB	107	rtc_read_time(rtc, &tm);
7ca1d488 DB	108	if (rtc_valid_tm(&tm) != 0) {
d4afc76c	109	pr_debug("%s: bogus resume time\n", dev_name(&rtc->dev));
7ca1d488 DB	110	return 0;
7ca1d488 DB	111	}
3dcad5ff JS	112	rtc_tm_to_time(&tm, &new_rtc.tv_sec);
	113	new_rtc.tv_nsec = 0;
	114
6a8943d9 AH	115	if (new_rtc.tv_sec < old_rtc.tv_sec) {
6a8943d9 AH	116	pr_debug("%s: time travel!\n", dev_name(&rtc->dev));
7ca1d488 DB	117	return 0;
	118	}
	119
3dcad5ff JS	120	/* calculate the RTC time delta (sleep time)*/
	121	sleep_time = timespec_sub(new_rtc, old_rtc);
	122
	123	/*
	124	* Since these RTC suspend/resume handlers are not called
	125	* at the very end of suspend or the start of resume,
	126	* some run-time may pass on either sides of the sleep time
	127	* so subtract kernel run-time between rtc_suspend to rtc_resume
	128	* to keep things accurate.
	129	*/
	130	sleep_time = timespec_sub(sleep_time,
	131	timespec_sub(new_system, old_system));
7ca1d488	132
6a8943d9 AH	133	if (sleep_time.tv_sec >= 0)
6a8943d9 AH	134	timekeeping_inject_sleeptime(&sleep_time);
4c24e29e	135	rtc_hctosys_ret = 0;
7ca1d488 DB	136	return 0;
	137	}
	138
92e7f04a SK	139	static SIMPLE_DEV_PM_OPS(rtc_class_dev_pm_ops, rtc_suspend, rtc_resume);
92e7f04a SK	140	#define RTC_CLASS_DEV_PM_OPS (&rtc_class_dev_pm_ops)
7ca1d488	141	#else
92e7f04a	142	#define RTC_CLASS_DEV_PM_OPS NULL
7ca1d488 DB	143	#endif
	144
	145
0c86edc0 AZ	146	/**
	147	* rtc_device_register - register w/ RTC class
	148	* @dev: the device to register
	149	*
	150	* rtc_device_unregister() must be called when the class device is no
	151	* longer needed.
	152	*
	153	* Returns the pointer to the new struct class device.
	154	*/
	155	struct rtc_device rtc_device_register(const char name, struct device *dev,
ff8371ac	156	const struct rtc_class_ops *ops,
0c86edc0 AZ	157	struct module *owner)
	158	{
	159	struct rtc_device *rtc;
f44f7f96	160	struct rtc_wkalrm alrm;
9d2b7e53 SW	161	int of_id = -1, id = -1, err;
	162
	163	if (dev->of_node)
	164	of_id = of_alias_get_id(dev->of_node, "rtc");
	165	else if (dev->parent && dev->parent->of_node)
	166	of_id = of_alias_get_id(dev->parent->of_node, "rtc");
	167
	168	if (of_id >= 0) {
	169	id = ida_simple_get(&rtc_ida, of_id, of_id + 1,
	170	GFP_KERNEL);
	171	if (id < 0)
	172	dev_warn(dev, "/aliases ID %d not available\n",
	173	of_id);
	174	}
0c86edc0	175
6d03d06d	176	if (id < 0) {
9d2b7e53 SW	177	id = ida_simple_get(&rtc_ida, 0, 0, GFP_KERNEL);
	178	if (id < 0) {
	179	err = id;
	180	goto exit;
	181	}
0c86edc0 AZ	182	}
0c86edc0 AZ	183
0c86edc0 AZ	184	rtc = kzalloc(sizeof(struct rtc_device), GFP_KERNEL);
	185	if (rtc == NULL) {
	186	err = -ENOMEM;
6d03d06d	187	goto exit_ida;
0c86edc0 AZ	188	}
	189
	190	rtc->id = id;
	191	rtc->ops = ops;
	192	rtc->owner = owner;
83a06bf5	193	rtc->irq_freq = 1;
110d693d	194	rtc->max_user_freq = 64;
cd966209 DB	195	rtc->dev.parent = dev;
	196	rtc->dev.class = rtc_class;
	197	rtc->dev.release = rtc_device_release;
0c86edc0 AZ	198
	199	mutex_init(&rtc->ops_lock);
	200	spin_lock_init(&rtc->irq_lock);
	201	spin_lock_init(&rtc->irq_task_lock);
d691eb90	202	init_waitqueue_head(&rtc->irq_queue);
0c86edc0	203
6610e089 JS	204	/* Init timerqueue */
6610e089 JS	205	timerqueue_init_head(&rtc->timerqueue);
96c8f06a	206	INIT_WORK(&rtc->irqwork, rtc_timer_do_work);
6610e089	207	/* Init aie timer */
96c8f06a	208	rtc_timer_init(&rtc->aie_timer, rtc_aie_update_irq, (void *)rtc);
6610e089	209	/* Init uie timer */
96c8f06a	210	rtc_timer_init(&rtc->uie_rtctimer, rtc_uie_update_irq, (void *)rtc);
6610e089 JS	211	/* Init pie timer */
	212	hrtimer_init(&rtc->pie_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
	213	rtc->pie_timer.function = rtc_pie_update_irq;
	214	rtc->pie_enabled = 0;
	215
f44f7f96 JS	216	/* Check to see if there is an ALARM already set in hw */
	217	err = __rtc_read_alarm(rtc, &alrm);
	218
	219	if (!err && !rtc_valid_tm(&alrm.time))
f6d5b331	220	rtc_initialize_alarm(rtc, &alrm);
f44f7f96	221
0c86edc0	222	strlcpy(rtc->name, name, RTC_DEVICE_NAME_SIZE);
d4afc76c	223	dev_set_name(&rtc->dev, "rtc%d", id);
0c86edc0	224
cb3a58d2 DB	225	rtc_dev_prepare(rtc);
cb3a58d2 DB	226
cd966209	227	err = device_register(&rtc->dev);
59cca865 VK	228	if (err) {
59cca865 VK	229	put_device(&rtc->dev);
0c86edc0	230	goto exit_kfree;
59cca865	231	}
0c86edc0	232
5726fb20	233	rtc_dev_add_device(rtc);
446ecbd9	234	rtc_sysfs_add_device(rtc);
7d9f99ec	235	rtc_proc_add_device(rtc);
5726fb20	236
0c86edc0	237	dev_info(dev, "rtc core: registered %s as %s\n",
d4afc76c	238	rtc->name, dev_name(&rtc->dev));
0c86edc0 AZ	239
	240	return rtc;
	241
	242	exit_kfree:
	243	kfree(rtc);
	244
6d03d06d JC	245	exit_ida:
6d03d06d JC	246	ida_simple_remove(&rtc_ida, id);
0c86edc0 AZ	247
0c86edc0 AZ	248	exit:
d1d65b77 AZ	249	dev_err(dev, "rtc core: unable to register %s, err = %d\n",
d1d65b77 AZ	250	name, err);
0c86edc0 AZ	251	return ERR_PTR(err);
	252	}
	253	EXPORT_SYMBOL_GPL(rtc_device_register);
	254
	255
	256	/**
	257	* rtc_device_unregister - removes the previously registered RTC class device
	258	*
	259	* @rtc: the RTC class device to destroy
	260	*/
	261	void rtc_device_unregister(struct rtc_device *rtc)
	262	{
cd966209	263	if (get_device(&rtc->dev) != NULL) {
e109ebd1 DB	264	mutex_lock(&rtc->ops_lock);
	265	/* remove innards of this RTC, then disable it, before
	266	* letting any rtc_class_open() users access it again
	267	*/
446ecbd9	268	rtc_sysfs_del_device(rtc);
5726fb20	269	rtc_dev_del_device(rtc);
7d9f99ec	270	rtc_proc_del_device(rtc);
cd966209	271	device_unregister(&rtc->dev);
e109ebd1 DB	272	rtc->ops = NULL;
e109ebd1 DB	273	mutex_unlock(&rtc->ops_lock);
cd966209	274	put_device(&rtc->dev);
e109ebd1	275	}
0c86edc0 AZ	276	}
	277	EXPORT_SYMBOL_GPL(rtc_device_unregister);
	278
3e217b66 JH	279	static void devm_rtc_device_release(struct device dev, void res)
	280	{
	281	struct rtc_device rtc = (struct rtc_device **)res;
	282
	283	rtc_device_unregister(rtc);
	284	}
	285
	286	static int devm_rtc_device_match(struct device dev, void res, void *data)
	287	{
	288	struct rtc **r = res;
	289
	290	return *r == data;
	291	}
	292
	293	/**
	294	* devm_rtc_device_register - resource managed rtc_device_register()
3e217b66	295	* @dev: the device to register
6636a994	296	* @name: the name of the device
3e217b66 JH	297	* @ops: the rtc operations structure
	298	* @owner: the module owner
	299	*
	300	* @return a struct rtc on success, or an ERR_PTR on error
	301	*
	302	* Managed rtc_device_register(). The rtc_device returned from this function
	303	* are automatically freed on driver detach. See rtc_device_register()
	304	* for more information.
	305	*/
	306
6636a994 JH	307	struct rtc_device devm_rtc_device_register(struct device dev,
6636a994 JH	308	const char *name,
3e217b66 JH	309	const struct rtc_class_ops *ops,
	310	struct module *owner)
	311	{
	312	struct rtc_device *ptr, rtc;
	313
	314	ptr = devres_alloc(devm_rtc_device_release, sizeof(*ptr), GFP_KERNEL);
	315	if (!ptr)
	316	return ERR_PTR(-ENOMEM);
	317
	318	rtc = rtc_device_register(name, dev, ops, owner);
	319	if (!IS_ERR(rtc)) {
	320	*ptr = rtc;
	321	devres_add(dev, ptr);
	322	} else {
	323	devres_free(ptr);
	324	}
	325
	326	return rtc;
	327	}
	328	EXPORT_SYMBOL_GPL(devm_rtc_device_register);
	329
	330	/**
	331	* devm_rtc_device_unregister - resource managed devm_rtc_device_unregister()
	332	* @dev: the device to unregister
	333	* @rtc: the RTC class device to unregister
	334	*
	335	* Deallocated a rtc allocated with devm_rtc_device_register(). Normally this
	336	* function will not need to be called and the resource management code will
	337	* ensure that the resource is freed.
	338	*/
	339	void devm_rtc_device_unregister(struct device dev, struct rtc_device rtc)
	340	{
	341	int rc;
	342
	343	rc = devres_release(dev, devm_rtc_device_release,
	344	devm_rtc_device_match, rtc);
	345	WARN_ON(rc);
	346	}
	347	EXPORT_SYMBOL_GPL(devm_rtc_device_unregister);
	348
0c86edc0 AZ	349	static int __init rtc_init(void)
	350	{
	351	rtc_class = class_create(THIS_MODULE, "rtc");
	352	if (IS_ERR(rtc_class)) {
c100a5e0	353	pr_err("couldn't create class\n");
0c86edc0 AZ	354	return PTR_ERR(rtc_class);
0c86edc0 AZ	355	}
92e7f04a	356	rtc_class->pm = RTC_CLASS_DEV_PM_OPS;
5726fb20	357	rtc_dev_init();
446ecbd9	358	rtc_sysfs_init(rtc_class);
0c86edc0 AZ	359	return 0;
	360	}
	361
	362	static void __exit rtc_exit(void)
	363	{
5726fb20	364	rtc_dev_exit();
0c86edc0	365	class_destroy(rtc_class);
6d03d06d	366	ida_destroy(&rtc_ida);
0c86edc0 AZ	367	}
0c86edc0 AZ	368
818a8674	369	subsys_initcall(rtc_init);
0c86edc0 AZ	370	module_exit(rtc_exit);
0c86edc0 AZ	371
818a8674	372	MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
0c86edc0 AZ	373	MODULE_DESCRIPTION("RTC class support");
0c86edc0 AZ	374	MODULE_LICENSE("GPL");