Incomplete shutdown when TWI2 in use with RTC module

[avafinger]

Kernel does not shutdown properly after i removed platform RTC_DRV_ATC206X and added a RTC module in TWI2.
Kernel writes garbage in RTC registers during shutdown.

[fshh520]

Hi, We used other RTC, no problem
Maybe you should check your DTS configuration is correct or not.

[avafinger]

Did you check the RTC time on next boot after at least 15 secs without power?
I used default DTS from Lemaker.
I will double check DTS and debug DS_1307 (my RTC module) and see what i can find.
Could you please tell which RTC module you are using?

[Alessia-Cao]

I've tried this method using DS_1307 module, it works both for Pro and Guitar. http://forum.lemaker.org/forum.php?mod=viewthread&tid=22932

[avafinger]

Alessia-Cao, thanks for taking the time and letting me know it works while in runtime, it works for me too.

Can you please do the following:
a) Set the current date and time and Turn off your guitar board (GUITAR please, forget about Allwinner platform)
b) Wait a few seconds (unplug DC power plug)
c) Before you turn on the guitar (without Ethernet and Wifi), start recording a complete boot log, until you login and issue a shutdown -h now from command line.
d) Attach the complete boot log, and i will provide my boot log with debugging info, so we can compare.

[avafinger]

I have recorded a sequence of 4 Bootings in a row in order to reproduce the problem.

On third boot sequence the RTC registers have garbage. I edited the boot sequence file to show where a New Boot sequence starts ( ----- NEW BOOT ----).
Also showed when 'hclock' has been called and its correspondent RTC command.

I also enabled RTC debugging to make sure the values passed to/from DS_1307 / RTC where good enough to be saved on RTC register.

I started with a boot with the problem, garbage values on RTC, set a future date and time and issued a shutdown command. (hwclock --set --date="01/12/2016 14:55:00")

1 - First boot was OK, but with incomplete shutdown ( by incomplete i mean the LCD is still with power and with a WHITE screen)
2 - Second also OK, shutdown a little farther than the previous.
3 - Third boot, problem with RTC

I attached also a shutdown sequence for Android to check _atc260x_pm_powerdown().

My best guess is the problem lies on atc260x_i2c, not on RTC or DS_1307.

Complete boot sequence for the Guitar with LCD 7", a camera and DS_1307 module attached:
guitar_rtc_debug.TXT

Android shutdown sequence:
[ 138.119823] SUSPEND pStatus->message_status is 0!!!!!!!!!!!!!!
[ 138.120243] owl_camera line:2386--owl_camera_shutdown() owl camera is
shutdown...
[ 138.120466] Power down.
[ 138.304355] [PM] owl_pm_halt 140:
[ 138.308297] atc260x_i2c 0-0065: _atc260x_i2c_direct_access_init() direct_acce
ss activated
[ 138.316533] atc260x_i2c 0-0065: reg access mode set to 1
[ 138.321903] Powering off (wakesrc: 0x102, deep_pwrdn:0)
[ 138.327159] atc260x-pm atc2603c-pm.0: _atc260x_pm_set_wakeup_src_inner() ente
r, mask=0x7fff src=0x102
[ 138.336836] atc260x-pm atc2603c-pm.0: _atc260x_pm_set_wakeup_src_inner() setu
p reg=0x0 msk=0xffe0 val=0x2040 readback=0x204b
[ 138.348388] atc260x-pm atc2603c-pm.0: _atc260x_pm_set_wakeup_src_inner() setu
p reg=0x3 msk=0xc val=0x0 readback=0x4280
[ 138.359410] atc260x-pm atc2603c-pm.0: _atc260x_pm_powerdown() enter, deep_pwr
dn=0 for_upgrade=0

[tab-liu]

Everything is going on well?
shutdown.txt
rtc.txt

[avafinger]

tab-liu Thanks for the log.

I should note some differences on your provided log:

• RTC platform is not disabled
  [ 3.639808] atc260x-rtc atc2603c-rtc.0: rtc core: registered atc260x-RTC as rtc0
• Date and time is still wrong:
  [ 3.674457] atc260x-rtc atc2603c-rtc.0: rtc core: registered atc260x-RTC as rtc0
  [ 3.682375] atc260x-rtc atc2603c-rtc.0: invalid year(0), reset to year 2011
• Ubuntu 14.04 set the date and time during shutdown (later versions do not), Debian 8 does not set date/time when you shutdown, as far as i remember there was a bug in the x86 bios that forced the developers on Debian/Ubuntu not to set date/time on shutting down.
• you tested I2C rtc communication and proved it works, but it does work for me too!.

Please, edit /etc/rc.local and write this two lines:
echo ds1307 0x68 > /sys/bus/i2c/devices/i2c-2/new_device
hwclock -s
[*Maybe you need to add sudo in front of each line (debian)]

Save it, reboot several times (at least five times and wait 15 secs to discharge any capacitor) and check if your system date is correct ( and not 2011...) (and don't plug ethernet or enable wifi).

If you have this working, you proved there is something wrong with my configuration or setup, and is not a kernel problem , module bug or it is possibly just a defective DS1307.

Appreciate if you could try it.