alarm clock on the kindle ?

[lrizzo]

Just noticed the following entry on the kindle

[root@kindle root]# cat /proc/driver/rtc
rtc_time : 04:09:51
rtc_date : 2010-12-02
alrm_time : 05:23:47
alrm_date : 2010-11-25
alarm_IRQ : no
alrm_pending : no
24hr : yes

and curiously enough, the alarm date is close to when i noticed
a spontaneous reboot of the kindle.
So i was wondering if there is a way to set the Kindle to wake up
at some programmed time ? This is probably more of a linux question...

[twobob]

Necro -bump
With a little extra flavour
https://www.kernel.org/doc/Documentation/rtc.txt


and interestingly...

[root@kindle root]# cat /proc/driver/rtc

rtc_time : 18:34:40
rtc_date : 2013-03-20
alrm_time : 12:24:31
alrm_date : 2059-09-19
alarm_IRQ : no
alrm_pending : no
24hr : yes

wonder when that changed...

EDIT: even more interestingly... 2059-09-19 12:24:31 is not a date that can even be calculated using the onboard busybox... nor ubuntu Mints date calculator... it's too far in the future or something...

however using our trusty online companion... http://www.onlineconversion.com/unix_time.htm

we can note that would be... 2831199871 - yeah. I can see how they came up with that one .... NOT... (some one's birthday? end of the world?)


Let's have a read of https://www.linux.com/learn/docs/672...tc-alarm-clock

which looks like fun...

[twobob]

Okay... so we need a helpful date format...

'date TIME' form accepts MMDDhhmm[[YY]YY][.ss]

so...

[root@kindle root]# echo `date -d "03201924" +%s`
1363807440 <-- Helpful

Here's one I tried earlier.

[root@kindle root]# echo "1363805893" > /sys/class/rtc/rtc0/wakealarm
[root@kindle root]# cat /sys/class/rtc/rtc0/wakealarm
[root@kindle root]# cat /proc/driver/rtc

rtc_time : 18:55:59
rtc_date : 2013-03-20
alrm_time : 18:58:13
alrm_date : 2013-03-20
alarm_IRQ : no
alrm_pending : no
24hr : yes

Let's see what explodes!
(need to figure out if alarm management has been nerfed in the kernel code I guess...)
at some point... Feel free anyone to chip in with knowledge. I have NONE (as usual)

Aaaaaaaaaaaaaand nothing exploded. lol...
nor did I note any output in any logs I found yet.
nor did it wake from a low power state or vice versa.

will dig in the configs

[twobob]

[root@kindle root]# zcat /proc/config.gz | grep -i rtc

CONFIG_RTC_LIB=y
CONFIG_RTC_CLASS=y
CONFIG_RTC_HCTOSYS=y
CONFIG_RTC_HCTOSYS_DEVICE="rtc0"
# CONFIG_RTC_DEBUG is not set
# RTC interfaces
CONFIG_RTC_INTF_SYSFS=y
CONFIG_RTC_INTF_PROC=y
CONFIG_RTC_INTF_DEV=y
# CONFIG_RTC_INTF_DEV_UIE_EMUL is not set
# CONFIG_RTC_DRV_TEST is not set
# I2C RTC drivers
# CONFIG_RTC_DRV_DS1307 is not set
# CONFIG_RTC_DRV_DS1374 is not set
# CONFIG_RTC_DRV_DS1672 is not set
# CONFIG_RTC_DRV_MAX6900 is not set
# CONFIG_RTC_DRV_RS5C372 is not set
# CONFIG_RTC_DRV_ISL1208 is not set
# CONFIG_RTC_DRV_X1205 is not set
# CONFIG_RTC_DRV_PCF8563 is not set
# CONFIG_RTC_DRV_PCF8583 is not set
# CONFIG_RTC_DRV_M41T80 is not set
# CONFIG_RTC_DRV_S35390A is not set
# CONFIG_RTC_DRV_FM3130 is not set
# SPI RTC drivers
# CONFIG_RTC_DRV_MAX6902 is not set
# CONFIG_RTC_DRV_R9701 is not set
# CONFIG_RTC_DRV_RS5C348 is not set
# Platform RTC drivers
# CONFIG_RTC_DRV_CMOS is not set
# CONFIG_RTC_DRV_DS1511 is not set
# CONFIG_RTC_DRV_DS1553 is not set
# CONFIG_RTC_DRV_DS1742 is not set
# CONFIG_RTC_DRV_STK17TA8 is not set
# CONFIG_RTC_DRV_M48T86 is not set
# CONFIG_RTC_DRV_M48T59 is not set
# CONFIG_RTC_DRV_V3020 is not set
# on-CPU RTC drivers
CONFIG_RTC_MXC=y
# CONFIG_RTC_DRV_MXC_V2 is not set
# CONFIG_RTC_DRV_IMXDI is not set
CONFIG_RTC_MC13892=y
CONFIG_MXC_MC13892_RTC=y

[twobob]

possibly some enterprising person might have to do something like.

https://git.kernel.org/cgit/linux/ke...9434822a6c1a73

but for the MXC_MC13892

Currently out of scope for my playtime.
But hey. it's a place to start digging. : )

[twobob]

Kernel versions 2.6.22 and newer use /sys/class/rtc/rtc0/wakealarm
[root@kindle root]# uname -a

Linux kindle 2.6.26-rt-lab126 #5 Sat Sep 1 14:28:26 PDT 2012 armv6l GNU/Linux

Note that kernel version 2.6.26, included in the current Debian stable distribution, contains a bug that makes ACPI wakeup fail on at least some motherboards. If this affects you, either upgrade to 2.6.33-rc4 or patch 2.6.26 with this patch.

Which is interesting if nothing else and may deserve a look.

also from http://www.mythtv.org/wiki/ACPI_Wakeup (Which is crammed with intersting stuff on this subject)


Disable hwclock updates?

The reason for this recommendation is that most Linux distributions write the current system time back to the RTC when shutting down the machine. With most RTCs, the machine will not wake up if the hardware clock has been modified after the wakeup alarm has been set. To avoid this, it is necessary to disable the writing of the current system time to the RTC by the system shutdown scripts. This is distribution specific, so here are some examples:

I'll skip the dull bits..

Let's check if we have a HWCLOCKACCESS=no in our /etc/default/rcS

[root@kindle root]# cat /etc/default/rcS

#
# Defaults for the boot scripts in /etc/rcS.d
#

# Time files in /tmp are kept in days.
TMPTIME=0
# Set to yes if you want sulogin to be spawned on bootup
SULOGIN=no
# Set to no if you want to be able to login over telnet/rlogin
# before system startup is complete (as soon as inetd is started)
DELAYLOGIN=no
# Set UTC=yes if your system clock is set to UTC (GMT), and UTC=no if not.
# UTC=yes
# Set VERBOSE to "no" if you would like a more quiet bootup.
VERBOSE=no
# Set EDITMOTD to "no" if you don't want /etc/motd to be editted automatically
EDITMOTD=no
# Set FSCKFIX to "yes" if you want to add "-y" to the fsck at startup.
FSCKFIX=yes
# Set TICKADJ to the correct tick value for this specific machine
#TICKADJ=10000
# Enable caching in populate-volatile.sh
VOLATILE_ENABLE_CACHE=yes

Seemingly not..

we use a custom upstart anyways more like ubuntu...

so perhaps we could do something in there as outlined on the page I linked to...

A cursory glance at /etc/init.d shows a lack of rtc stuffage

[root@kindle root]# /etc/init.d/

/etc/init.d/audio /etc/init.d/pmond
/etc/init.d/battcheck /etc/init.d/power
/etc/init.d/boot_finished /etc/init.d/powerd
/etc/init.d/bootmisc.sh /etc/init.d/pre-wifid
/etc/init.d/browserd /etc/init.d/rc
/etc/init.d/chpriority /etc/init.d/rcS
/etc/init.d/ckimage /etc/init.d/reboot
/etc/init.d/cmd /etc/init.d/rootfsresize
/etc/init.d/cron /etc/init.d/scroll
/etc/init.d/dbus /etc/init.d/sdtime_start
/etc/init.d/diag_reboot /etc/init.d/sdtime_stop
/etc/init.d/diags /etc/init.d/syslog-ng
/etc/init.d/ethernet /etc/init.d/system
/etc/init.d/filesystems /etc/init.d/testd
/etc/init.d/framework /etc/init.d/tmd
/etc/init.d/governor /etc/init.d/ttsd
/etc/init.d/guidinit /etc/init.d/udev
/etc/init.d/halt /etc/init.d/updater
/etc/init.d/hostname /etc/init.d/usbnet
/etc/init.d/init_time /etc/init.d/usbnetd
/etc/init.d/kdb /etc/init.d/userstore
/etc/init.d/kernel_toggle /etc/init.d/video
/etc/init.d/launchpad /etc/init.d/volumd
/etc/init.d/linkjail /etc/init.d/wan
/etc/init.d/lipc-daemon /etc/init.d/wand
/etc/init.d/mcsd /etc/init.d/webreaderd
/etc/init.d/modules /etc/init.d/wifi

Again. outside my playtime allowance for right now.


One more thing.. is rtc or rtc-cmos a module?

[root@kindle root]# lsmod

Module Size Used by
ar6000 161076 0
g_ether 21096 0
arcotg_udc 38628 1 g_ether
option 12512 1
usbserial 27756 3 option
ehci_hcd 38880 1 option
usbcore 136388 4 option,usbserial,ehci_hcd
volume 8900 1
fiveway 23552 1
mxc_keyb 15904 1
uinput 7776 0
fuse 48348 2
mwan 7324 1 ehci_hcd
eink_fb_shim 116732 0
eink_fb_hal_broads 397532 0
eink_fb_hal 59764 8 eink_fb_shim,eink_fb_hal_broads

No. For the record.

[twobob]

hmm.... more thoughts...

I feel that the issue is really something to do with the actual state of the system.

a shutdown -h now does indeed halt the system (don't try that at home kids)

so perhaps a recrafting of what HALT actually "does" and testing if it resumes from that state is in fact in order...

might have a look at that.


[root@kindle root]# echo `date -d "03210028" +%s` > /sys/class/rtc/rtc0/wakealarm
[root@kindle root]# cat /proc/driver/rtc

rtc_time : 00:27:32
rtc_date : 2013-03-21
alrm_time : 00:28:00
alrm_date : 2013-03-21
alarm_IRQ : no
alrm_pending : no
24hr : yes

[root@kindle root]# shutdown -h now

Broadcast message from root (pts/5) (Thu Mar 21 00:27:39 2013):

The system is going down for system halt NOW!

EDIT: Okay that didnt work to wake it up neither...

hmm... maybe I need to load the rtc-cmos module...

[twobob]

for info on the k5

[root@kindle root]# cat /sys/class/rtc/rtc1/

/sys/class/rtc/rtc1/date           /sys/class/rtc/rtc1/since_epoch
/sys/class/rtc/rtc1/dev            /sys/class/rtc/rtc1/subsystem/
/sys/class/rtc/rtc1/device/        /sys/class/rtc/rtc1/time
/sys/class/rtc/rtc1/max_user_freq  /sys/class/rtc/rtc1/uevent
/sys/class/rtc/rtc1/name           /sys/class/rtc/rtc1/wakealarm
/sys/class/rtc/rtc1/power/

[root@kindle root]# cat /sys/class/rtc/rtc0/

/sys/class/rtc/rtc0/date           /sys/class/rtc/rtc0/power/
/sys/class/rtc/rtc0/dev            /sys/class/rtc/rtc0/since_epoch
/sys/class/rtc/rtc0/device/        /sys/class/rtc/rtc0/subsystem/
/sys/class/rtc/rtc0/max_user_freq  /sys/class/rtc/rtc0/time
/sys/class/rtc/rtc0/name           /sys/class/rtc/rtc0/uevent

so there are in fact two on there.

[brianinmaine]

Love where this is headed! Wakeup from low power! Wish I knew what to do with the info you posted...

[twobob]

To be honest I knew NOTHING about this 24 hours ago. And I still know ALMOST nothing...
This was all really just to get your clock port somewhere useful.

# CONFIG_RTC_DRV_CMOS is not set may be part of the problem. We probably have that module lying around now. I honestly have ZERO idea. As usual.

But I never let a lack of understanding get in the way of "Having A Go".

: )

[hawhill]

The PMIC (power management IC) has RTC capabilities, including wake-up. So yes, it can wake up from "almost off" mode (i.e. only PMIC powered).

Of course, the Kindle can wake up from it's normal "sleep" state at any time by normal software control. It's still running, after all, though it has nothing to do and the SoC has a quite good low-power idle mode.

[brianinmaine]

Originally Posted by hawhill

The PMIC (power management IC) has RTC capabilities, including wake-up. So yes, it can wake up from "almost off" mode (i.e. only PMIC powered).

Of course, the Kindle can wake up from it's normal "sleep" state at any time by normal software control. It's still running, after all, though it has nothing to do and the SoC has a quite good low-power idle mode.

How can this be done? I thought the only way to wake it is by pressing the power button (K5)?

[hawhill]

I know of no user interface to do so, but software can trigger a wake-up -- after all, that's what actually happens upon pressing the power button. I'm sure I've seen the needed commands to wake up the normal user interface framework, too - some call to the lipc framework.

[knc1]

Originally Posted by twobob

for info on the k5

[root@kindle root]# cat /sys/class/rtc/rtc1/

/sys/class/rtc/rtc1/date           /sys/class/rtc/rtc1/since_epoch
/sys/class/rtc/rtc1/dev            /sys/class/rtc/rtc1/subsystem/
/sys/class/rtc/rtc1/device/        /sys/class/rtc/rtc1/time
/sys/class/rtc/rtc1/max_user_freq  /sys/class/rtc/rtc1/uevent
/sys/class/rtc/rtc1/name           /sys/class/rtc/rtc1/wakealarm
/sys/class/rtc/rtc1/power/

[root@kindle root]# cat /sys/class/rtc/rtc0/

/sys/class/rtc/rtc0/date           /sys/class/rtc/rtc0/power/
/sys/class/rtc/rtc0/dev            /sys/class/rtc/rtc0/since_epoch
/sys/class/rtc/rtc0/device/        /sys/class/rtc/rtc0/subsystem/
/sys/class/rtc/rtc0/max_user_freq  /sys/class/rtc/rtc0/time
/sys/class/rtc/rtc0/name           /sys/class/rtc/rtc0/uevent

so there are in fact two on there.

Set the above as required (research probably needed to determine those settings)

Echo the "memory" power state into /sys/power
(Exact commands accepted may depend on which of the three kernels your devices runs - learn those by cat'ing the same entry).

Then wait.

The above should only depend on the kernel's interface to the hardware it is running on. "Below" any application programs.