diff options
| author | Atsushi Nemoto <anemo@mba.ocn.ne.jp> | 2005-11-03 01:01:15 +0900 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2005-11-07 18:05:38 +0000 |
| commit | 53c2df2f4ebbc1d8231ca7cc13ac5381230888b1 (patch) | |
| tree | a7446ec56dd877d77ef7318b4bcdc3d38555ff0a /arch/mips/sibyte/swarm/rtc_m41t81.c | |
| parent | e329331aedeca0f2a7e15bd26a829ee1619c05e0 (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/sibyte/swarm/rtc_m41t81.c')
| -rw-r--r-- | arch/mips/sibyte/swarm/rtc_m41t81.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/mips/sibyte/swarm/rtc_m41t81.c b/arch/mips/sibyte/swarm/rtc_m41t81.c index 5b4fc26c1b36..c13914bdda59 100644 --- a/arch/mips/sibyte/swarm/rtc_m41t81.c +++ b/arch/mips/sibyte/swarm/rtc_m41t81.c @@ -144,6 +144,7 @@ static int m41t81_write(uint8_t addr, int b) int m41t81_set_time(unsigned long t) { struct rtc_time tm; + unsigned long flags; to_tm(t, &tm); @@ -153,6 +154,7 @@ int m41t81_set_time(unsigned long t) * believe we should finish writing min within a second. */ + spin_lock_irqsave(&rtc_lock, flags); tm.tm_sec = BIN2BCD(tm.tm_sec); m41t81_write(M41T81REG_SC, tm.tm_sec); @@ -180,6 +182,7 @@ int m41t81_set_time(unsigned long t) tm.tm_year %= 100; tm.tm_year = BIN2BCD(tm.tm_year); m41t81_write(M41T81REG_YR, tm.tm_year); + spin_unlock_irqrestore(&rtc_lock, flags); return 0; } @@ -187,19 +190,23 @@ int m41t81_set_time(unsigned long t) unsigned long m41t81_get_time(void) { unsigned int year, mon, day, hour, min, sec; + unsigned long flags; /* * min is valid if two reads of sec are the same. */ for (;;) { + spin_lock_irqsave(&rtc_lock, flags); sec = m41t81_read(M41T81REG_SC); min = m41t81_read(M41T81REG_MN); if (sec == m41t81_read(M41T81REG_SC)) break; + spin_unlock_irqrestore(&rtc_lock, flags); } hour = m41t81_read(M41T81REG_HR) & 0x3f; day = m41t81_read(M41T81REG_DT); mon = m41t81_read(M41T81REG_MO); year = m41t81_read(M41T81REG_YR); + spin_unlock_irqrestore(&rtc_lock, flags); sec = BCD2BIN(sec); min = BCD2BIN(min); |