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authorJonathan Cameron <jic23@cam.ac.uk>2009-01-07 01:42:12 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2009-01-07 02:59:24 +0300
commit5d2a50371ddf127afa782ad3147469be8e9bd69f (patch)
treebc7b7032512c17f493e5f656044c79c17952f517 /drivers/rtc/rtc-cmos.c
parent2fac6674ddf3164da42a76d62f8912073d629a30 (diff)
downloadlinux-5d2a50371ddf127afa782ad3147469be8e9bd69f.tar.xz
rtc: move power of 2 periodic frequency check down into drivers
Move the power of 2 check on frequencies down into individual rtc drivers This is to allow for non power of 2 real time clock periodic interrupts such as those on the pxa27x to be found in the new pxa27x-rtc driver Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Alessandro Zummo <a.zummo@towertech.it> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/rtc/rtc-cmos.c')
-rw-r--r--drivers/rtc/rtc-cmos.c3
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index cf98a5d8358e..b6d35f50e404 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -35,6 +35,7 @@
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/mod_devicetable.h>
+#include <linux/log2.h>
/* this is for "generic access to PC-style RTC" using CMOS_READ/CMOS_WRITE */
#include <asm-generic/rtc.h>
@@ -384,6 +385,8 @@ static int cmos_irq_set_freq(struct device *dev, int freq)
if (!is_valid_irq(cmos->irq))
return -ENXIO;
+ if (!is_power_of_2(freq))
+ return -EINVAL;
/* 0 = no irqs; 1 = 2^15 Hz ... 15 = 2^0 Hz */
f = ffs(freq);
if (f-- > 16)