linux-imx

#include <linux/bcd.h>

#include <linux/delay.h>

#include <linux/export.h>

#include <linux/mc146818rtc.h>

​

#ifdef CONFIG_ACPI

#include <linux/acpi.h>

#endif

​

/*

 * Returns true if a clock update is in progress

 */

static inline unsigned char mc146818_is_updating(void)

{

    unsigned char uip;

    unsigned long flags;

​

    spin_lock_irqsave(&rtc_lock, flags);

    uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP);

    spin_unlock_irqrestore(&rtc_lock, flags);

    return uip;

}

​

unsigned int mc146818_get_time(struct rtc_time *time)

{

    unsigned char ctrl;

    unsigned long flags;

    unsigned char century = 0;

​

#ifdef CONFIG_MACH_DECSTATION

    unsigned int real_year;

#endif

​

    /*

     * read RTC once any update in progress is done. The update

     * can take just over 2ms. We wait 20ms. There is no need to

     * to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP.

     * If you need to know *exactly* when a second has started, enable

     * periodic update complete interrupts, (via ioctl) and then

     * immediately read /dev/rtc which will block until you get the IRQ.

     * Once the read clears, read the RTC time (again via ioctl). Easy.

     */

    if (mc146818_is_updating())

        mdelay(20);

​

    /*

     * Only the values that we read from the RTC are set. We leave

     * tm_wday, tm_yday and tm_isdst untouched. Even though the

     * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated

     * by the RTC when initially set to a non-zero value.

     */

    spin_lock_irqsave(&rtc_lock, flags);

    time->tm_sec = CMOS_READ(RTC_SECONDS);

    time->tm_min = CMOS_READ(RTC_MINUTES);

    time->tm_hour = CMOS_READ(RTC_HOURS);

    time->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH);

    time->tm_mon = CMOS_READ(RTC_MONTH);

    time->tm_year = CMOS_READ(RTC_YEAR);

#ifdef CONFIG_MACH_DECSTATION

    real_year = CMOS_READ(RTC_DEC_YEAR);

#endif

#ifdef CONFIG_ACPI

    if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&