diff options
Diffstat (limited to 'arch/mn10300/kernel')
-rw-r--r-- | arch/mn10300/kernel/rtc.c | 104 |
1 files changed, 9 insertions, 95 deletions
diff --git a/arch/mn10300/kernel/rtc.c b/arch/mn10300/kernel/rtc.c index 77e0be4d92ea..f81f37025072 100644 --- a/arch/mn10300/kernel/rtc.c +++ b/arch/mn10300/kernel/rtc.c @@ -12,107 +12,19 @@ #include <linux/module.h> #include <linux/init.h> #include <linux/mc146818rtc.h> -#include <linux/bcd.h> -#include <linux/timex.h> +#include <linux/ioport.h> +#include <linux/platform_device.h> + #include <asm/rtc-regs.h> #include <asm/rtc.h> DEFINE_SPINLOCK(rtc_lock); EXPORT_SYMBOL(rtc_lock); -/* - * Read the current RTC time - */ -void read_persistent_clock(struct timespec *ts) -{ - struct rtc_time tm; - - mc146818_set_time(&tm); - - ts->tv_nsec = 0; - ts->tv_sec = mktime(tm.tm_year, tm.tm_mon, tm.tm_mday, - tm.tm_hour, tm.tm_min, tm.tm_sec); - - /* if rtc is way off in the past, set something reasonable */ - if (ts->tv_sec < 0) - ts->tv_sec = mktime(2009, 1, 1, 12, 0, 0); -} - -/* - * In order to set the CMOS clock precisely, set_rtc_mmss has to be called 500 - * ms after the second nowtime has started, because when nowtime is written - * into the registers of the CMOS clock, it will jump to the next second - * precisely 500 ms later. Check the Motorola MC146818A or Dallas DS12887 data - * sheet for details. - * - * BUG: This routine does not handle hour overflow properly; it just - * sets the minutes. Usually you'll only notice that after reboot! - */ -static int set_rtc_mmss(unsigned long nowtime) -{ - unsigned char save_control, save_freq_select; - int retval = 0; - int real_seconds, real_minutes, cmos_minutes; - - /* gets recalled with irq locally disabled */ - spin_lock(&rtc_lock); - save_control = CMOS_READ(RTC_CONTROL); /* tell the clock it's being - * set */ - CMOS_WRITE(save_control | RTC_SET, RTC_CONTROL); - - save_freq_select = CMOS_READ(RTC_FREQ_SELECT); /* stop and reset - * prescaler */ - CMOS_WRITE(save_freq_select | RTC_DIV_RESET2, RTC_FREQ_SELECT); - - cmos_minutes = CMOS_READ(RTC_MINUTES); - if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) - cmos_minutes = bcd2bin(cmos_minutes); - - /* - * since we're only adjusting minutes and seconds, - * don't interfere with hour overflow. This avoids - * messing with unknown time zones but requires your - * RTC not to be off by more than 15 minutes - */ - real_seconds = nowtime % 60; - real_minutes = nowtime / 60; - if (((abs(real_minutes - cmos_minutes) + 15) / 30) & 1) - /* correct for half hour time zone */ - real_minutes += 30; - real_minutes %= 60; - - if (abs(real_minutes - cmos_minutes) < 30) { - if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { - real_seconds = bin2bcd(real_seconds); - real_minutes = bin2bcd(real_minutes); - } - CMOS_WRITE(real_seconds, RTC_SECONDS); - CMOS_WRITE(real_minutes, RTC_MINUTES); - } else { - printk_once(KERN_NOTICE - "set_rtc_mmss: can't update from %d to %d\n", - cmos_minutes, real_minutes); - retval = -1; - } - - /* The following flags have to be released exactly in this order, - * otherwise the DS12887 (popular MC146818A clone with integrated - * battery and quartz) will not reset the oscillator and will not - * update precisely 500 ms later. You won't find this mentioned in - * the Dallas Semiconductor data sheets, but who believes data - * sheets anyway ... -- Markus Kuhn - */ - CMOS_WRITE(save_control, RTC_CONTROL); - CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT); - spin_unlock(&rtc_lock); - - return retval; -} - -int update_persistent_clock(struct timespec now) -{ - return set_rtc_mmss(now.tv_sec); -} +static const __initdata struct resource res[] = { + DEFINE_RES_IO(RTC_PORT(0), RTC_IO_EXTENT), + DEFINE_RES_IRQ(RTC_IRQ), +}; /* * calibrate the TSC clock against the RTC @@ -129,4 +41,6 @@ void __init calibrate_clock(void) RTCRA |= RTCRA_DVR; RTCRA &= ~RTCRA_DVR; RTCRB &= ~RTCRB_SET; + + platform_device_register_simple("rtc_cmos", -1, res, ARRAY_SIZE(res)); } |