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>
diff --git a/arch/mips/lasat/ds1603.c b/arch/mips/lasat/ds1603.c
index 9d7812e..7dced67 100644
--- a/arch/mips/lasat/ds1603.c
+++ b/arch/mips/lasat/ds1603.c
@@ -8,6 +8,7 @@
#include <asm/lasat/lasat.h>
#include <linux/delay.h>
#include <asm/lasat/ds1603.h>
+#include <asm/time.h>
#include "ds1603.h"
@@ -138,19 +139,27 @@
unsigned long ds1603_read(void)
{
unsigned long word;
+ unsigned long flags;
+
+ spin_lock_irqsave(&rtc_lock, flags);
rtc_init_op();
rtc_write_byte(READ_TIME_CMD);
word = rtc_read_word();
rtc_end_op();
+ spin_unlock_irqrestore(&rtc_lock, flags);
return word;
}
int ds1603_set(unsigned long time)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&rtc_lock, flags);
rtc_init_op();
rtc_write_byte(SET_TIME_CMD);
rtc_write_word(time);
rtc_end_op();
+ spin_unlock_irqrestore(&rtc_lock, flags);
return 0;
}