[patch 1/3] clockevents: Use u32 for mult and shift factors

[Thomas Gleixner]

The mult and shift factors of clock events differ in their data type
from those of clock sources for no reason. u32 is sufficient for
both. shift is always <= 32 and mult is limited to 2^32-1 to avoid
64bit multiplication overflows in the conversion.

Preparatory patch for a generic mult/shift factor calculation
function.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Mikael Pettersson <mikpe@xxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: Linus Walleij <linus.walleij@xxxxxxxxxxxxxx>
Cc: John Stultz <johnstul@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
---
 include/linux/clockchips.h |    4 ++--
 kernel/time/timer_list.c   |    4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

Index: linux-2.6-tip/include/linux/clockchips.h
===================================================================
--- linux-2.6-tip.orig/include/linux/clockchips.h
+++ linux-2.6-tip/include/linux/clockchips.h
@@ -79,8 +79,8 @@ struct clock_event_device {
 	unsigned int		features;
 	unsigned long		max_delta_ns;
 	unsigned long		min_delta_ns;
-	unsigned long		mult;
-	int			shift;
+	u32			mult;
+	u32			shift;
 	int			rating;
 	int			irq;
 	const struct cpumask	*cpumask;
Index: linux-2.6-tip/kernel/time/timer_list.c
===================================================================
--- linux-2.6-tip.orig/kernel/time/timer_list.c
+++ linux-2.6-tip/kernel/time/timer_list.c
@@ -206,8 +206,8 @@ print_tickdevice(struct seq_file *m, str
 	SEQ_printf(m, "%s\n", dev->name);
 	SEQ_printf(m, " max_delta_ns:   %lu\n", dev->max_delta_ns);
 	SEQ_printf(m, " min_delta_ns:   %lu\n", dev->min_delta_ns);
-	SEQ_printf(m, " mult:           %lu\n", dev->mult);
-	SEQ_printf(m, " shift:          %d\n", dev->shift);
+	SEQ_printf(m, " mult:           %u\n", dev->mult);
+	SEQ_printf(m, " shift:          %u\n", dev->shift);
 	SEQ_printf(m, " mode:           %d\n", dev->mode);
 	SEQ_printf(m, " next_event:     %Ld nsecs\n",
 		   (unsigned long long) ktime_to_ns(dev->next_event));


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