diff options
author | David Brownell <david-b@pacbell.net> | 2007-10-16 12:28:16 +0400 |
---|---|---|
committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-16 20:43:13 +0400 |
commit | 97144c67566241db46633727f2860e6428373fe4 (patch) | |
tree | b3863ed198037668cb80df710678a6e249842654 /drivers/rtc/rtc-cmos.c | |
parent | d691eb901e044065de10756ea78a5758d457c7fd (diff) | |
download | linux-97144c67566241db46633727f2860e6428373fe4.tar.xz |
rtc_irq_set_freq() requires power-of-two and associated kerneldoc
RTC periodic IRQs are only defined to work for 2^N Hz values. This patch
moves that validity check into the infrastructure, so drivers don't need to
check it; and adds kerneldoc for the two interface functions related to
periodic IRQs. (One of which was quite mysterious until its first use was
recently checked in!)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
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.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c index 5d760bb6c2cd..6d0c35397b49 100644 --- a/drivers/rtc/rtc-cmos.c +++ b/drivers/rtc/rtc-cmos.c @@ -246,11 +246,9 @@ static int cmos_irq_set_freq(struct device *dev, int freq) /* 0 = no irqs; 1 = 2^15 Hz ... 15 = 2^0 Hz */ f = ffs(freq); - if (f != 0) { - if (f-- > 16 || freq != (1 << f)) - return -EINVAL; - f = 16 - f; - } + if (f-- > 16) + return -EINVAL; + f = 16 - f; spin_lock_irqsave(&rtc_lock, flags); CMOS_WRITE(RTC_REF_CLCK_32KHZ | f, RTC_FREQ_SELECT); |