[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / rtc / interface.c

/*
 * RTC subsystem, interface functions
 *
 * 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/rtc.h>

int rtc_read_time(struct class_device *class_dev, struct rtc_time *tm)
{
	int err;
	struct rtc_device *rtc = to_rtc_device(class_dev);

	err = mutex_lock_interruptible(&rtc->ops_lock);
	if (err)
		return -EBUSY;

	if (!rtc->ops)
		err = -ENODEV;
	else if (!rtc->ops->read_time)
		err = -EINVAL;
	else {
		memset(tm, 0, sizeof(struct rtc_time));
		err = rtc->ops->read_time(class_dev->dev, tm);
	}

	mutex_unlock(&rtc->ops_lock);
	return err;
}
EXPORT_SYMBOL_GPL(rtc_read_time);

int rtc_set_time(struct class_device *class_dev, struct rtc_time *tm)
{
	int err;
	struct rtc_device *rtc = to_rtc_device(class_dev);

	err = rtc_valid_tm(tm);
	if (err != 0)
		return err;

	err = mutex_lock_interruptible(&rtc->ops_lock);
	if (err)
		return -EBUSY;

	if (!rtc->ops)
		err = -ENODEV;
	else if (!rtc->ops->set_time)
		err = -EINVAL;
	else
		err = rtc->ops->set_time(class_dev->dev, tm);

	mutex_unlock(&rtc->ops_lock);
	return err;
}
EXPORT_SYMBOL_GPL(rtc_set_time);

int rtc_set_mmss(struct class_device *class_dev, unsigned long secs)
{
	int err;
	struct rtc_device *rtc = to_rtc_device(class_dev);

	err = mutex_lock_interruptible(&rtc->ops_lock);
	if (err)
		return -EBUSY;

	if (!rtc->ops)
		err = -ENODEV;
	else if (rtc->ops->set_mmss)
		err = rtc->ops->set_mmss(class_dev->dev, secs);
	else if (rtc->ops->read_time && rtc->ops->set_time) {
		struct rtc_time new, old;

		err = rtc->ops->read_time(class_dev->dev, &old);
		if (err == 0) {
			rtc_time_to_tm(secs, &new);

			/*
			 * avoid writing when we're going to change the day of
			 * the month. We will retry in the next minute. This
			 * basically means that if the RTC must not drift
			 * by more than 1 minute in 11 minutes.
			 */
			if (!((old.tm_hour == 23 && old.tm_min == 59) ||
				(new.tm_hour == 23 && new.tm_min == 59)))
				err = rtc->ops->set_time(class_dev->dev, &new);
		}
	}
	else
		err = -EINVAL;

	mutex_unlock(&rtc->ops_lock);

	return err;
}
EXPORT_SYMBOL_GPL(rtc_set_mmss);

int rtc_read_alarm(struct class_device *class_dev, struct rtc_wkalrm *alarm)
{
	int err;
	struct rtc_device *rtc = to_rtc_device(class_dev);

	err = mutex_lock_interruptible(&rtc->ops_lock);
	if (err)
		return -EBUSY;

	if (rtc->ops == NULL)
		err = -ENODEV;
	else if (!rtc->ops->read_alarm)
		err = -EINVAL;
	else {
		memset(alarm, 0, sizeof(struct rtc_wkalrm));
		err = rtc->ops->read_alarm(class_dev->dev, alarm);
	}

	mutex_unlock(&rtc->ops_lock);
	return err;
}
EXPORT_SYMBOL_GPL(rtc_read_alarm);

int rtc_set_alarm(struct class_device *class_dev, struct rtc_wkalrm *alarm)
{
	int err;
	struct rtc_device *rtc = to_rtc_device(class_dev);

	err = mutex_lock_interruptible(&rtc->ops_lock);
	if (err)
		return -EBUSY;

	if (!rtc->ops)
		err = -ENODEV;
	else if (!rtc->ops->set_alarm)
		err = -EINVAL;
	else
		err = rtc->ops->set_alarm(class_dev->dev, alarm);

	mutex_unlock(&rtc->ops_lock);
	return err;
}
EXPORT_SYMBOL_GPL(rtc_set_alarm);

/**
 * rtc_update_irq - report RTC periodic, alarm, and/or update irqs
 * @class_dev: the rtc's class device
 * @num: how many irqs are being reported (usually one)
 * @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF
 * Context: in_interrupt(), irqs blocked
 */
void rtc_update_irq(struct class_device *class_dev,
		unsigned long num, unsigned long events)
{
	struct rtc_device *rtc = to_rtc_device(class_dev);

	spin_lock(&rtc->irq_lock);
	rtc->irq_data = (rtc->irq_data + (num << 8)) | events;
	spin_unlock(&rtc->irq_lock);

	spin_lock(&rtc->irq_task_lock);
	if (rtc->irq_task)
		rtc->irq_task->func(rtc->irq_task->private_data);
	spin_unlock(&rtc->irq_task_lock);

	wake_up_interruptible(&rtc->irq_queue);
	kill_fasync(&rtc->async_queue, SIGIO, POLL_IN);
}
EXPORT_SYMBOL_GPL(rtc_update_irq);

struct class_device *rtc_class_open(char *name)
{
	struct class_device *class_dev = NULL,
				*class_dev_tmp;

	down(&rtc_class->sem);
	list_for_each_entry(class_dev_tmp, &rtc_class->children, node) {
		if (strncmp(class_dev_tmp->class_id, name, BUS_ID_SIZE) == 0) {
			class_dev = class_device_get(class_dev_tmp);
			break;
		}
	}

	if (class_dev) {
		if (!try_module_get(to_rtc_device(class_dev)->owner))
			class_dev = NULL;
	}
	up(&rtc_class->sem);

	return class_dev;
}
EXPORT_SYMBOL_GPL(rtc_class_open);

void rtc_class_close(struct class_device *class_dev)
{
	module_put(to_rtc_device(class_dev)->owner);
	class_device_put(class_dev);
}
EXPORT_SYMBOL_GPL(rtc_class_close);

int rtc_irq_register(struct class_device *class_dev, struct rtc_task *task)
{
	int retval = -EBUSY;
	struct rtc_device *rtc = to_rtc_device(class_dev);

	if (task == NULL || task->func == NULL)
		return -EINVAL;

	spin_lock_irq(&rtc->irq_task_lock);
	if (rtc->irq_task == NULL) {
		rtc->irq_task = task;
		retval = 0;
	}
	spin_unlock_irq(&rtc->irq_task_lock);

	return retval;
}
EXPORT_SYMBOL_GPL(rtc_irq_register);

void rtc_irq_unregister(struct class_device *class_dev, struct rtc_task *task)
{
	struct rtc_device *rtc = to_rtc_device(class_dev);

	spin_lock_irq(&rtc->irq_task_lock);
	if (rtc->irq_task == task)
		rtc->irq_task = NULL;
	spin_unlock_irq(&rtc->irq_task_lock);
}
EXPORT_SYMBOL_GPL(rtc_irq_unregister);

int rtc_irq_set_state(struct class_device *class_dev, struct rtc_task *task, int enabled)
{
	int err = 0;
	unsigned long flags;
	struct rtc_device *rtc = to_rtc_device(class_dev);

	if (rtc->ops->irq_set_state == NULL)
		return -ENXIO;

	spin_lock_irqsave(&rtc->irq_task_lock, flags);
	if (rtc->irq_task != task)
		err = -ENXIO;
	spin_unlock_irqrestore(&rtc->irq_task_lock, flags);

	if (err == 0)
		err = rtc->ops->irq_set_state(class_dev->dev, enabled);

	return err;
}
EXPORT_SYMBOL_GPL(rtc_irq_set_state);

int rtc_irq_set_freq(struct class_device *class_dev, struct rtc_task *task, int freq)
{
	int err = 0;
	unsigned long flags;
	struct rtc_device *rtc = to_rtc_device(class_dev);

	if (rtc->ops->irq_set_freq == NULL)
		return -ENXIO;

	spin_lock_irqsave(&rtc->irq_task_lock, flags);
	if (rtc->irq_task != task)
		err = -ENXIO;
	spin_unlock_irqrestore(&rtc->irq_task_lock, flags);

	if (err == 0) {
		err = rtc->ops->irq_set_freq(class_dev->dev, freq);
		if (err == 0)
			rtc->irq_freq = freq;
	}
	return err;
}
EXPORT_SYMBOL_GPL(rtc_irq_set_freq);
Commit	Line	Data
0c86edc0 AZ	1	/*
	2	* RTC subsystem, interface functions
	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/rtc.h>
	15
	16	int rtc_read_time(struct class_device class_dev, struct rtc_time tm)
	17	{
	18	int err;
	19	struct rtc_device *rtc = to_rtc_device(class_dev);
	20
	21	err = mutex_lock_interruptible(&rtc->ops_lock);
	22	if (err)
	23	return -EBUSY;
	24
	25	if (!rtc->ops)
	26	err = -ENODEV;
	27	else if (!rtc->ops->read_time)
	28	err = -EINVAL;
	29	else {
	30	memset(tm, 0, sizeof(struct rtc_time));
	31	err = rtc->ops->read_time(class_dev->dev, tm);
	32	}
	33
	34	mutex_unlock(&rtc->ops_lock);
	35	return err;
	36	}
	37	EXPORT_SYMBOL_GPL(rtc_read_time);
	38
	39	int rtc_set_time(struct class_device class_dev, struct rtc_time tm)
	40	{
	41	int err;
	42	struct rtc_device *rtc = to_rtc_device(class_dev);
	43
	44	err = rtc_valid_tm(tm);
	45	if (err != 0)
	46	return err;
	47
	48	err = mutex_lock_interruptible(&rtc->ops_lock);
	49	if (err)
	50	return -EBUSY;
	51
	52	if (!rtc->ops)
	53	err = -ENODEV;
	54	else if (!rtc->ops->set_time)
	55	err = -EINVAL;
	56	else
	57	err = rtc->ops->set_time(class_dev->dev, tm);
	58
	59	mutex_unlock(&rtc->ops_lock);
	60	return err;
	61	}
	62	EXPORT_SYMBOL_GPL(rtc_set_time);
	63
	64	int rtc_set_mmss(struct class_device *class_dev, unsigned long secs)
65	{
66	int err;
67	struct rtc_device *rtc = to_rtc_device(class_dev);
68
69	err = mutex_lock_interruptible(&rtc->ops_lock);
70	if (err)
71	return -EBUSY;
72
73	if (!rtc->ops)
74	err = -ENODEV;
75	else if (rtc->ops->set_mmss)
76	err = rtc->ops->set_mmss(class_dev->dev, secs);
77	else if (rtc->ops->read_time && rtc->ops->set_time) {
78	struct rtc_time new, old;
79
80	err = rtc->ops->read_time(class_dev->dev, &old);
81	if (err == 0) {
82	rtc_time_to_tm(secs, &new);
83
84	/*
85	* avoid writing when we're going to change the day of
86	* the month. We will retry in the next minute. This
87	* basically means that if the RTC must not drift
88	* by more than 1 minute in 11 minutes.
89	*/
90	if (!((old.tm_hour == 23 && old.tm_min == 59) \|\|
91	(new.tm_hour == 23 && new.tm_min == 59)))
92	err = rtc->ops->set_time(class_dev->dev, &new);
93	}
94	}
95	else
96	err = -EINVAL;
97
98	mutex_unlock(&rtc->ops_lock);
99
100	return err;
101	}
102	EXPORT_SYMBOL_GPL(rtc_set_mmss);
103
104	int rtc_read_alarm(struct class_device class_dev, struct rtc_wkalrm alarm)
105	{
106	int err;
107	struct rtc_device *rtc = to_rtc_device(class_dev);
108
109	err = mutex_lock_interruptible(&rtc->ops_lock);
110	if (err)
111	return -EBUSY;
112
113	if (rtc->ops == NULL)
114	err = -ENODEV;
115	else if (!rtc->ops->read_alarm)
116	err = -EINVAL;
117	else {
118	memset(alarm, 0, sizeof(struct rtc_wkalrm));
119	err = rtc->ops->read_alarm(class_dev->dev, alarm);
120	}
121
122	mutex_unlock(&rtc->ops_lock);
123	return err;
124	}
125	EXPORT_SYMBOL_GPL(rtc_read_alarm);
126
127	int rtc_set_alarm(struct class_device class_dev, struct rtc_wkalrm alarm)
128	{
129	int err;
130	struct rtc_device *rtc = to_rtc_device(class_dev);
131
132	err = mutex_lock_interruptible(&rtc->ops_lock);
133	if (err)
134	return -EBUSY;
135
136	if (!rtc->ops)
137	err = -ENODEV;
138	else if (!rtc->ops->set_alarm)
139	err = -EINVAL;
140	else
141	err = rtc->ops->set_alarm(class_dev->dev, alarm);
142
143	mutex_unlock(&rtc->ops_lock);
144	return err;
145	}
146	EXPORT_SYMBOL_GPL(rtc_set_alarm);
147
d728b1e6 DB	148	/**
	149	* rtc_update_irq - report RTC periodic, alarm, and/or update irqs
	150	* @class_dev: the rtc's class device
	151	* @num: how many irqs are being reported (usually one)
	152	* @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF
	153	* Context: in_interrupt(), irqs blocked
	154	*/
0c86edc0 AZ	155	void rtc_update_irq(struct class_device *class_dev,
	156	unsigned long num, unsigned long events)
	157	{
	158	struct rtc_device *rtc = to_rtc_device(class_dev);
	159
	160	spin_lock(&rtc->irq_lock);
	161	rtc->irq_data = (rtc->irq_data + (num << 8)) \| events;
	162	spin_unlock(&rtc->irq_lock);
	163
	164	spin_lock(&rtc->irq_task_lock);
	165	if (rtc->irq_task)
	166	rtc->irq_task->func(rtc->irq_task->private_data);
	167	spin_unlock(&rtc->irq_task_lock);
	168
	169	wake_up_interruptible(&rtc->irq_queue);
	170	kill_fasync(&rtc->async_queue, SIGIO, POLL_IN);
	171	}
	172	EXPORT_SYMBOL_GPL(rtc_update_irq);
	173
	174	struct class_device rtc_class_open(char name)
	175	{
	176	struct class_device *class_dev = NULL,
	177	*class_dev_tmp;
	178
	179	down(&rtc_class->sem);
	180	list_for_each_entry(class_dev_tmp, &rtc_class->children, node) {
	181	if (strncmp(class_dev_tmp->class_id, name, BUS_ID_SIZE) == 0) {
e109ebd1	182	class_dev = class_device_get(class_dev_tmp);
0c86edc0 AZ	183	break;
	184	}
	185	}
	186
	187	if (class_dev) {
	188	if (!try_module_get(to_rtc_device(class_dev)->owner))
	189	class_dev = NULL;
	190	}
	191	up(&rtc_class->sem);
	192
	193	return class_dev;
	194	}
	195	EXPORT_SYMBOL_GPL(rtc_class_open);
	196
	197	void rtc_class_close(struct class_device *class_dev)
	198	{
	199	module_put(to_rtc_device(class_dev)->owner);
e109ebd1	200	class_device_put(class_dev);
0c86edc0 AZ	201	}
	202	EXPORT_SYMBOL_GPL(rtc_class_close);
	203
	204	int rtc_irq_register(struct class_device class_dev, struct rtc_task task)
	205	{
	206	int retval = -EBUSY;
	207	struct rtc_device *rtc = to_rtc_device(class_dev);
	208
	209	if (task == NULL \|\| task->func == NULL)
	210	return -EINVAL;
	211
d728b1e6	212	spin_lock_irq(&rtc->irq_task_lock);
0c86edc0 AZ	213	if (rtc->irq_task == NULL) {
	214	rtc->irq_task = task;
	215	retval = 0;
	216	}
d728b1e6	217	spin_unlock_irq(&rtc->irq_task_lock);
0c86edc0 AZ	218
	219	return retval;
	220	}
	221	EXPORT_SYMBOL_GPL(rtc_irq_register);
	222
	223	void rtc_irq_unregister(struct class_device class_dev, struct rtc_task task)
	224	{
	225	struct rtc_device *rtc = to_rtc_device(class_dev);
	226
d728b1e6	227	spin_lock_irq(&rtc->irq_task_lock);
0c86edc0 AZ	228	if (rtc->irq_task == task)
0c86edc0 AZ	229	rtc->irq_task = NULL;
d728b1e6	230	spin_unlock_irq(&rtc->irq_task_lock);
0c86edc0 AZ	231	}
	232	EXPORT_SYMBOL_GPL(rtc_irq_unregister);
	233
	234	int rtc_irq_set_state(struct class_device class_dev, struct rtc_task task, int enabled)
	235	{
	236	int err = 0;
	237	unsigned long flags;
	238	struct rtc_device *rtc = to_rtc_device(class_dev);
	239
56f10c63 AZ	240	if (rtc->ops->irq_set_state == NULL)
	241	return -ENXIO;
	242
0c86edc0 AZ	243	spin_lock_irqsave(&rtc->irq_task_lock, flags);
	244	if (rtc->irq_task != task)
	245	err = -ENXIO;
	246	spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
	247
	248	if (err == 0)
	249	err = rtc->ops->irq_set_state(class_dev->dev, enabled);
	250
	251	return err;
	252	}
	253	EXPORT_SYMBOL_GPL(rtc_irq_set_state);
	254
	255	int rtc_irq_set_freq(struct class_device class_dev, struct rtc_task task, int freq)
	256	{
56f10c63	257	int err = 0;
0c86edc0 AZ	258	unsigned long flags;
	259	struct rtc_device *rtc = to_rtc_device(class_dev);
	260
56f10c63 AZ	261	if (rtc->ops->irq_set_freq == NULL)
56f10c63 AZ	262	return -ENXIO;
0c86edc0 AZ	263
	264	spin_lock_irqsave(&rtc->irq_task_lock, flags);
	265	if (rtc->irq_task != task)
	266	err = -ENXIO;
	267	spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
	268
	269	if (err == 0) {
	270	err = rtc->ops->irq_set_freq(class_dev->dev, freq);
	271	if (err == 0)
	272	rtc->irq_freq = freq;
	273	}
	274	return err;
	275	}
2601a464	276	EXPORT_SYMBOL_GPL(rtc_irq_set_freq);