linux-kernel - RTC-CMOS ALARM fields always resetted on reboot on x86

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Date:	Wed, 14 Nov 2012 13:42:37 +0100
From:	Andy Hirsh <andhirsh@...il.com>
To:	linux-kernel@...r.kernel.org
Subject: RTC-CMOS ALARM fields always resetted on reboot on x86

Hi all

I'm having a strange behaviour with the RTC upgrading from kernel
2.6.32/2.6.34 to 2.6.38.8 on x86:

the rtc_cmos alarm time&date fields are always set to 00:00:00
1970-01-01 after the boot process...

eg:

cat /proc/driver/rtc  before reboot:

rtc_time        : 12:07:11
rtc_date        : 2012-11-14
alrm_time       : 09:01:20
alrm_date       : 2012-11-15
alarm_IRQ       : no
alrm_pending    : no
24hr            : yes
periodic_IRQ    : no
update_IRQ      : no
HPET_emulated   : yes
BCD             : yes
DST_enable      : no
periodic_freq   : 1024
batt_status     : okay

after reboot:

rtc_time        : 12:15:39
rtc_date        : 2012-11-14
alrm_time       : 00:00:00
alrm_date       : 1970-01-01
alarm_IRQ       : no
alrm_pending    : no
24hr            : yes
periodic_IRQ    : no
update_IRQ      : no
HPET_emulated   : yes
BCD             : yes
DST_enable      : no
periodic_freq   : 1024
batt_status     : okay

during the boot process, the kernel reports:

...
rtc_cmos 00:03: RTC can wake from S4
rtc_cmos 00:03: rtc core: registered rtc_cmos as rtc0
rtc0: alarms up to one month, y3k, 114 bytes nvram, hpet irqs
...

with kernels 2.6.32.5 or 2.6.34.5 there are no problems... alarms
date&time values are not resetted.

     thanks a lot for any ideas...

             andy
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