linux-imx

/*

 * 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>

#include <linux/sched.h>

#include <linux/module.h>

#include <linux/log2.h>

#include <linux/workqueue.h>

​

#define CREATE_TRACE_POINTS

#include <trace/events/rtc.h>

​

static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer);

static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer);

​

static void rtc_add_offset(struct rtc_device *rtc, struct rtc_time *tm)

{

    time64_t secs;

​

    if (!rtc->offset_secs)

        return;

​

    secs = rtc_tm_to_time64(tm);

​

    /*

     * Since the reading time values from RTC device are always in the RTC

     * original valid range, but we need to skip the overlapped region

     * between expanded range and original range, which is no need to add

     * the offset.

     */

    if ((rtc->start_secs > rtc->range_min && secs >= rtc->start_secs) ||

        (rtc->start_secs < rtc->range_min &&

         secs <= (rtc->start_secs + rtc->range_max - rtc->range_min)))

        return;

​

    rtc_time64_to_tm(secs + rtc->offset_secs, tm);

}

​

static void rtc_subtract_offset(struct rtc_device *rtc, struct rtc_time *tm)

{

    time64_t secs;

​

    if (!rtc->offset_secs)

        return;

​

    secs = rtc_tm_to_time64(tm);

​

    /*

     * If the setting time values are in the valid range of RTC hardware

     * device, then no need to subtract the offset when setting time to RTC

     * device. Otherwise we need to subtract the offset to make the time

     * values are valid for RTC hardware device.

     */