/* * 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_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_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);