diff options
| author | Boris BREZILLON <boris.brezillon@free-electrons.com> | 2014-06-06 14:36:09 -0700 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2014-06-23 10:27:53 +0200 |
| commit | ba576fd015636729ae6c55bd96f56014c2526571 (patch) | |
| tree | b249b5840b32144567adfafc5c0662c8d9bada60 /drivers/target | |
| parent | 07d054ef6765b307277f02c11b51f0695d6b3d7c (diff) | |
rtc: rtc-at91rm9200: fix infinite wait for ACKUPD irq
commit 2fe121e1f5aa3bf31b418a9790db6c400e922291 upstream.
The rtc user must wait at least 1 sec between each time/calandar update
(see atmel's datasheet chapter "Updating Time/Calendar").
Use the 1Hz interrupt to update the at91_rtc_upd_rdy flag and wait for
the at91_rtc_wait_upd_rdy event if the rtc is not ready.
This patch fixes a deadlock in an uninterruptible wait when the RTC is
updated more than once every second. AFAICT the bug is here from the
beginning, but I think we should at least backport this fix to 3.10 and
the following longterm and stable releases.
Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Reported-by: Bryan Evenson <bevenson@melinkcorp.com>
Tested-by: Bryan Evenson <bevenson@melinkcorp.com>
Cc: Andrew Victor <linux@maxim.org.za>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
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>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Diffstat (limited to 'drivers/target')
0 files changed, 0 insertions, 0 deletions