rtc: file close() consistently disables repeating irqs
authorDavid Brownell <dbrownell@users.sourceforge.net>
Thu, 16 Oct 2008 05:03:04 +0000 (22:03 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 16 Oct 2008 18:21:40 +0000 (11:21 -0700)
commit743e6a504f81d1e2f086e726b69fb6631d11f820
tree6fe23cd6708db3e95fcad00ef7af12253e97d063
parent37fc5e2c42833c32f7c8eb5d9b3a3115bb37d9c3
rtc: file close() consistently disables repeating irqs

Make the rtc framework consistent about disabling 1/second update IRQs
that may have been activated through the /dev interface, when that /dev
file is closed.  (It may have closed because of coredump, etc.) This was
previously done only for emulated update IRQs ...  now, do it always.

Also comment the current policy: repeating IRQs (periodic, update) that
userspace enabled will be cleanly disabled, but alarms are left alone.
Such repeating IRQs are a constant and pointless system load.

Update some RTC drivers to remove now-needless release() methods.  Most
such methods just enforce that policy.  The others all seem to be buggy,
and mistreat in-kernel clients of periodic or alarm IRQs.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Andrew Sharp <andy.sharp@onstor.com>
Cc: Angelo Castello <angelo.castello@st.com>
Acked-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Thomas Hommel <thomas.hommel@gefanuc.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/rtc/rtc-dev.c
drivers/rtc/rtc-ds1511.c
drivers/rtc/rtc-ds1553.c
drivers/rtc/rtc-sh.c
drivers/rtc/rtc-stk17ta8.c