[PATCH] add suspend/resume for timer

The timers lack .suspend/.resume methods.  Because of this, jiffies got a
big compensation after a S3 resume.  And then softlockup watchdog reports
an oops.  This occured with HPET enabled, but it's also possible for other
timers.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c
index 0ee9dee8af06..6f794a78ee1e 100644
--- a/arch/i386/kernel/time.c
+++ b/arch/i386/kernel/time.c
@@ -383,6 +383,7 @@ void notify_arch_cmos_timer(void)
 
 static long clock_cmos_diff, sleep_start;
 
+static struct timer_opts *last_timer;
 static int timer_suspend(struct sys_device *dev, pm_message_t state)
 {
         /*
@@ -391,6 +392,10 @@ static int timer_suspend(struct sys_device *dev, pm_message_t state)
         clock_cmos_diff = -get_cmos_time();
         clock_cmos_diff += get_seconds();
         sleep_start = get_cmos_time();
+        last_timer = cur_timer;
+        cur_timer = &timer_none;
+        if (last_timer->suspend)
+                last_timer->suspend(state);
         return 0;
 }
 
@@ -404,6 +409,7 @@ static int timer_resume(struct sys_device *dev)
         if (is_hpet_enabled())
                 hpet_reenable();
 #endif
+        setup_pit_timer();
         sec = get_cmos_time() + clock_cmos_diff;
         sleep_length = (get_cmos_time() - sleep_start) * HZ;
         write_seqlock_irqsave(&xtime_lock, flags);
@@ -412,6 +418,10 @@ static int timer_resume(struct sys_device *dev)
         write_sequnlock_irqrestore(&xtime_lock, flags);
         jiffies += sleep_length;
         wall_jiffies += sleep_length;
+        if (last_timer->resume)
+                last_timer->resume();
+        cur_timer = last_timer;
+        last_timer = NULL;
         return 0;
 }