Can’t get Real-Time Clock to Work

[suksit]

I installed Raspbian using ua-netinst successfully but when I followed the guide to add RTC to Raspberry Pi B+ (http://www.drewkeller.com/blog/adding-hardware-clock-raspberry-pi-ds3231), it didn’t work.

I got some error when running sudo hwclock --debug saying that it can’t find /dev/rtc.

So I tried to follow the same guide on the official Raspbian image and the RTC was installed successfully. Any ideas/suggestions?

Thanks!

[diederikdehaas]

Maybe change /etc/default/hwclock and remove the line with HWCLOCKACCESS=no ?
This command is probably also needed update-rc.d fake-hwclock disable
You probably have to reboot afterwards.
I don't have a RTC device myself, so this is only educated guessing.

[suksit]

Still didn’t work :/

Thanks for your suggestion, I’ll keep trying to find a solution.

[diederikdehaas]

Have you tried removing the fake-hwclock altogether?
apt-get remove --purge fake-hwclock

[suksit]

Yep I removed fake-hwclock along with editing /etc/default/hwclock.

However, I think I know why the RTC device doesn’t show up. It’s because I don’t have rtc-ds1307.ko in /lib/modules/... directory.

I got the RTC working by running rpi-update to get the latest kernel and modules. Maybe not the correct way to go but it’s the easiest I guess :P

[diederikdehaas]

and after running rpi-update you do have the rtc-ds1307.ko file?

[diederikdehaas]

Confirmed:
From /boot/config-3.18.0-trunk-rpi2:
CONFIG_RTC_DRV_DS1307 is not set
with kernel 3.18.12-v7+ zgrep RTC_DRV_DS1307 /proc/config.gz :
CONFIG_RTC_DRV_DS1307=m

[suksit]

Yes.

With the fresh install I got only like three .ko files in /lib/module//kernel/drivers/rtc/

After running rpi-update, there are like 10-20 .ko files in /lib/module//kernel/drivers/rtc/

[diederikdehaas]

I asked for support for the same RTC devices as the raspberrypi.org kernel supports:
https://bugs.launchpad.net/raspbian/+bug/1470679

[diederikdehaas]

The upstream issue as been resolved and (thus) so is this one.

@suksit Can you verify that that is indeed the case?

[suksit]

Confirmed that the module is there after a fresh install and RTC clock works as expected.

Thanks for the follow-up :D

[diederikdehaas]

👍