interface.c 6.1 KB
Newer Older
A
Alessandro Zummo 已提交
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231
/*
 * 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);

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

232 233 234
	if (rtc->ops->irq_set_state == NULL)
		return -ENXIO;

A
Alessandro Zummo 已提交
235 236 237 238 239 240 241 242 243 244 245 246 247 248
	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)
{
249
	int err = 0;
A
Alessandro Zummo 已提交
250 251 252
	unsigned long flags;
	struct rtc_device *rtc = to_rtc_device(class_dev);

253 254
	if (rtc->ops->irq_set_freq == NULL)
		return -ENXIO;
A
Alessandro Zummo 已提交
255 256 257 258 259 260 261 262 263 264 265 266 267

	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;
}
268
EXPORT_SYMBOL_GPL(rtc_irq_set_freq);