[RFC v4 19/22] clockevents: purge ->min_delta_ns and ->max_delta_ns

[Nicolai Stange]

The struct clock_event_device ->min_delta_ns and ->max_delta_ns aren't
used anymore.

Purge them.

In __clockevents_update_bounds(), shortcut the
  ->min_delta_ticks => ->min_delta_ns => ->min_delta_ticks_adjusted
calculation detour -- it had been made solely for the purpose of ensuring
that ->min_delta_ticks_adjusted corresponds to something >= 1us.

Signed-off-by: Nicolai Stange <nicsta...@gmail.com>
---
 include/linux/clockchips.h |  4 ----
 kernel/time/clockevents.c  | 13 +++++--------
 2 files changed, 5 insertions(+), 12 deletions(-)

diff --git a/include/linux/clockchips.h b/include/linux/clockchips.h
index 8578e24..4b71882 100644
--- a/include/linux/clockchips.h
+++ b/include/linux/clockchips.h
@@ -87,8 +87,6 @@ enum clock_event_state {
  * @tick_resume:       resume clkevt device
  * @broadcast:         function to broadcast events
  * @min_delta_ticks:   minimum delta value in ticks stored for reconfiguration
- * @max_delta_ns:      maximum delta value in ns
- * @min_delta_ns:      minimum delta value in ns
  * @name:              ptr to clock event name
  * @rating:            variable to rate clock event devices
  * @irq:               IRQ number (only for non CPU local devices)
@@ -120,8 +118,6 @@ struct clock_event_device {
        void                    (*suspend)(struct clock_event_device *);
        void                    (*resume)(struct clock_event_device *);
        unsigned long           min_delta_ticks;
-       u64                     max_delta_ns;
-       u64                     min_delta_ns;
 
        const char              *name;
        int                     rating;
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index bb3b98c..c59d6f2 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -444,15 +444,12 @@ static void __clockevents_update_bounds(struct 
clock_event_device *dev)
                return;
 
        /*
-        * cev_delta2ns() never returns values less than 1us and thus,
-        * we'll never program any ced with anything less.
+        * Enforce ->min_delta_ticks_adjusted to correspond to a value
+        * >= 1us.
         */
-       dev->min_delta_ns = cev_delta2ns(dev->min_delta_ticks, dev, false);
-       dev->max_delta_ns = cev_delta2ns(dev->max_delta_ticks, dev, true);
-       dev->min_delta_ticks_adjusted = (unsigned long)((dev->min_delta_ns *
-                                               dev->mult) >> dev->shift);
-       dev->min_delta_ticks_adjusted = max(dev->min_delta_ticks_adjusted,
-                                               dev->min_delta_ticks);
+       dev->min_delta_ticks_adjusted =
+               max(dev->min_delta_ticks,
+                       (unsigned long)((1000ULL * dev->mult) >> dev->shift));
 }
 
 /**
-- 
2.9.2