diff options
| author | Sergey Yanovich <ynvich@gmail.com> | 2013-07-04 02:07:46 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-07-04 03:07:59 +0400 |
| commit | dfc657b1330990213a3865aaef9d8af563ccad51 (patch) | |
| tree | 412b7c83788b31c5448376c3663acd17390fa869 /mm | |
| parent | 25d053cf1040e6430fff679854b3710edb0b7fee (diff) | |
| download | linux-dfc657b1330990213a3865aaef9d8af563ccad51.tar.xz | |
drivers/rtc/rtc-ds1302.c: handle write protection
This chip has a control register and can prevent altering saved clock.
Without this patch we could have:
(arm)root@pac14:~# date
Tue May 21 03:08:27 MSK 2013
(arm)root@pac14:~# /etc/init.d/hwclock.sh show
Tue May 21 11:13:58 2013 -0.067322 seconds
(arm)root@pac14:~# /etc/init.d/hwclock.sh stop
[info] Saving the system clock.
[info] Hardware Clock updated to Tue May 21 03:09:01 MSK 2013.
(arm)root@pac14:~# /etc/init.d/hwclock.sh show
Tue May 21 11:14:15 2013 -0.624272 seconds
The patch enables write access to rtc before the driver tries to write
time and re-disables when time data is written.
Signed-off-by: Sergey Yanovich <ynvich@gmail.com>
Acked-by: Marc Zyngier <maz@misterjones.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
0 files changed, 0 insertions, 0 deletions