2 files changed, 28 insertions, 71 deletions

diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index 1219be4fb42..a1ef46f61c8 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -268,64 +268,6 @@ static inline u32 clocksource_hz2mult(u32 hz, u32 shift_constant)
 }
 
 /**
- * clocksource_read: - Access the clocksource's current cycle value
- * @cs:         pointer to clocksource being read
- *
- * Uses the clocksource to return the current cycle_t value
- */
-static inline cycle_t clocksource_read(struct clocksource *cs)
-{
-        return cs->read(cs);
-}
-
-/**
- * clocksource_enable: - enable clocksource
- * @cs:         pointer to clocksource
- *
- * Enables the specified clocksource. The clocksource callback
- * function should start up the hardware and setup mult and field
- * members of struct clocksource to reflect hardware capabilities.
- */
-static inline int clocksource_enable(struct clocksource *cs)
-{
-        int ret = 0;
-
-        if (cs->enable)
-                ret = cs->enable(cs);
-
-        /*
-         * The frequency may have changed while the clocksource
-         * was disabled. If so the code in ->enable() must update
-         * the mult value to reflect the new frequency. Make sure
-         * mult_orig follows this change.
-         */
-        cs->mult_orig = cs->mult;
-
-        return ret;
-}
-
-/**
- * clocksource_disable: - disable clocksource
- * @cs:         pointer to clocksource
- *
- * Disables the specified clocksource. The clocksource callback
- * function should power down the now unused hardware block to
- * save power.
- */
-static inline void clocksource_disable(struct clocksource *cs)
-{
-        /*
-         * Save mult_orig in mult so clocksource_enable() can
-         * restore the value regardless if ->enable() updates
-         * the value of mult or not.
-         */
-        cs->mult = cs->mult_orig;
-
-        if (cs->disable)
-                cs->disable(cs);
-}
-
-/**
  * cyc2ns - converts clocksource cycles to nanoseconds
  * @cs:         Pointer to clocksource
  * @cycles:     Cycles
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index b8b70fb545f..016a2591d71 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -79,7 +79,7 @@ static void clocksource_forward_now(void)
         cycle_t cycle_now, cycle_delta;
         s64 nsec;
 
-        cycle_now = clocksource_read(clock);
+        cycle_now = clock->read(clock);
         cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
         clock->cycle_last = cycle_now;
 
@@ -114,7 +114,7 @@ void getnstimeofday(struct timespec *ts)
                 *ts = xtime;
 
                 /* read clocksource: */
-                cycle_now = clocksource_read(clock);
+                cycle_now = clock->read(clock);
 
                 /* calculate the delta since the last update_wall_time: */
                 cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
@@ -146,7 +146,7 @@ ktime_t ktime_get(void)
                 nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec;
 
                 /* read clocksource: */
-                cycle_now = clocksource_read(clock);
+                cycle_now = clock->read(clock);
 
                 /* calculate the delta since the last update_wall_time: */
                 cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
@@ -186,7 +186,7 @@ void ktime_get_ts(struct timespec *ts)
                 tomono = wall_to_monotonic;
 
                 /* read clocksource: */
-                cycle_now = clocksource_read(clock);
+                cycle_now = clock->read(clock);
 
                 /* calculate the delta since the last update_wall_time: */
                 cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
@@ -274,16 +274,29 @@ static void change_clocksource(void)
 
         clocksource_forward_now();
 
-        if (clocksource_enable(new))
+        if (new->enable && !new->enable(new))
                 return;
+        /*
+         * The frequency may have changed while the clocksource
+         * was disabled. If so the code in ->enable() must update
+         * the mult value to reflect the new frequency. Make sure
+         * mult_orig follows this change.
+         */
+        new->mult_orig = new->mult;
 
         new->raw_time = clock->raw_time;
         old = clock;
         clock = new;
-        clocksource_disable(old);
+        /*
+         * Save mult_orig in mult so that the value can be restored
+         * regardless if ->enable() updates the value of mult or not.
+         */
+        old->mult = old->mult_orig;
+        if (old->disable)
+                old->disable(old);
 
         clock->cycle_last = 0;
-        clock->cycle_last = clocksource_read(clock);
+        clock->cycle_last = clock->read(clock);
         clock->error = 0;
         clock->xtime_nsec = 0;
         clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
@@ -373,7 +386,7 @@ void getrawmonotonic(struct timespec *ts)
                 seq = read_seqbegin(&xtime_lock);
 
                 /* read clocksource: */
-                cycle_now = clocksource_read(clock);
+                cycle_now = clock->read(clock);
 
                 /* calculate the delta since the last update_wall_time: */
                 cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
@@ -435,9 +448,12 @@ void __init timekeeping_init(void)
         ntp_init();
 
         clock = clocksource_get_next();
-        clocksource_enable(clock);
+        if (clock->enable)
+                clock->enable(clock);
+        /* set mult_orig on enable */
+        clock->mult_orig = clock->mult;
         clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
-        clock->cycle_last = clocksource_read(clock);
+        clock->cycle_last = clock->read(clock);
 
         xtime.tv_sec = sec;
         xtime.tv_nsec = 0;
@@ -477,8 +493,7 @@ static int timekeeping_resume(struct sys_device *dev)
         }
         update_xtime_cache(0);
         /* re-base the last cycle value */
-        clock->cycle_last = 0;
-        clock->cycle_last = clocksource_read(clock);
+        clock->cycle_last = clock->read(clock);
         clock->error = 0;
         timekeeping_suspended = 0;
         write_sequnlock_irqrestore(&xtime_lock, flags);
@@ -630,7 +645,7 @@ void update_wall_time(void)
                 return;
 
 #ifdef CONFIG_GENERIC_TIME
-        offset = (clocksource_read(clock) - clock->cycle_last) & clock->mask;
+        offset = (clock->read(clock) - clock->cycle_last) & clock->mask;
 #else
         offset = clock->cycle_interval;
 #endif