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authorAtsushi Nemoto <anemo@mba.ocn.ne.jp>2005-11-03 01:01:15 +0900
committerRalf Baechle <ralf@linux-mips.org>2005-11-07 18:05:38 +0000
commit53c2df2f4ebbc1d8231ca7cc13ac5381230888b1 (patch)
treea7446ec56dd877d77ef7318b4bcdc3d38555ff0a /arch/mips/jmr3927/common/rtc_ds1742.c
parente329331aedeca0f2a7e15bd26a829ee1619c05e0 (diff)
Use rtc_lock to protect RTC operations
Many RTC routines were not protected against each other, so there are potential races, for example, ntp-update against /dev/rtc. This patch fixes them using rtc_lock. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/jmr3927/common/rtc_ds1742.c')
-rw-r--r--arch/mips/jmr3927/common/rtc_ds1742.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/mips/jmr3927/common/rtc_ds1742.c b/arch/mips/jmr3927/common/rtc_ds1742.c
index 1ae4318e135..8b407d7dc46 100644
--- a/arch/mips/jmr3927/common/rtc_ds1742.c
+++ b/arch/mips/jmr3927/common/rtc_ds1742.c
@@ -57,7 +57,9 @@ rtc_ds1742_get_time(void)
{
unsigned int year, month, day, hour, minute, second;
unsigned int century;
+ unsigned long flags;
+ spin_lock_irqsave(&rtc_lock, flags);
CMOS_WRITE(RTC_READ, RTC_CONTROL);
second = BCD2BIN(CMOS_READ(RTC_SECONDS) & RTC_SECONDS_MASK);
minute = BCD2BIN(CMOS_READ(RTC_MINUTES));
@@ -67,6 +69,7 @@ rtc_ds1742_get_time(void)
year = BCD2BIN(CMOS_READ(RTC_YEAR));
century = BCD2BIN(CMOS_READ(RTC_CENTURY) & RTC_CENTURY_MASK);
CMOS_WRITE(0, RTC_CONTROL);
+ spin_unlock_irqrestore(&rtc_lock, flags);
year += century * 100;
@@ -81,7 +84,9 @@ rtc_ds1742_set_time(unsigned long t)
u8 year, month, day, hour, minute, second;
u8 cmos_year, cmos_month, cmos_day, cmos_hour, cmos_minute, cmos_second;
int cmos_century;
+ unsigned long flags;
+ spin_lock_irqsave(&rtc_lock, flags);
CMOS_WRITE(RTC_READ, RTC_CONTROL);
cmos_second = (u8)(CMOS_READ(RTC_SECONDS) & RTC_SECONDS_MASK);
cmos_minute = (u8)CMOS_READ(RTC_MINUTES);
@@ -139,6 +144,7 @@ rtc_ds1742_set_time(unsigned long t)
/* RTC_CENTURY and RTC_CONTROL share same address... */
CMOS_WRITE(cmos_century, RTC_CONTROL);
+ spin_unlock_irqrestore(&rtc_lock, flags);
return 0;
}