raspbee 2 RTC problem

Dresden-Elektronik Hardware
1

Hi, I have a problem with the RTC on RaspBee2. It has worked before, but not anymore. Everything is up to date. I tried to reinstall the script. I2C interface is active in raspi-config.
Deconz works and all devices are connected. It is installed on a Raspberry Pi 4b using raspberry pi os.

Here is some information from my system:

cat /etc/os-release

PRETTY_NAME=“Debian GNU/Linux 12 (bookworm)”
NAME=“Debian GNU/Linux”
VERSION_ID=“12”
VERSION=“12 (bookworm)”
VERSION_CODENAME=bookworm
ID=debian
HOME_URL=“https://www.debian.org/”
SUPPORT_URL=“Debian -- User Support”
BUG_REPORT_URL=“https://bugs.debian.org/”

uname -r

6.12.34+rpt-rpi-v8

Jul 31 18:19:44 rasp2 systemd[1]: Started rtc-pcf85063.service - Enable RTC-PCF85063.
Jul 31 18:19:44 rasp2 bash[16223]: /bin/bash: line 1: /sys/class/i2c-adapter/i2c-1/new_device: No such file or directory
Jul 31 18:19:44 rasp2 systemd[1]: rtc-pcf85063.service: Main process exited, code=exited, status=1/FAILURE
Jul 31 18:19:44 rasp2 systemd[1]: rtc-pcf85063.service: Failed with result ‘exit-code’.
Jul 31 18:19:59 rasp2 systemd[1]: rtc-pcf85063.service: Scheduled restart job, restart counter is at 479.
Jul 31 18:19:59 rasp2 systemd[1]: Stopped rtc-pcf85063.service - Enable RTC-PCF85063.
Jul 31 18:19:59 rasp2 systemd[1]: Started rtc-pcf85063.service - Enable RTC-PCF85063.

As you can see there is no “/sys/class/i2c-adapter/i2c-1/new_device”.

i2cdetect -y 1

 0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f

00: – – – – – – – –
10: – – – – – – – – – – – – – – – –
20: – – – – – – – – – – – – – – – –
30: – – – – – – – – – – – – – – – –
40: – – – – – – – – – – – – – – – –
50: – 51 – – – – – – – – – – – – – –
60: – – – – – – – – – – – – – – – –
70: – – – – – – – –

raspi-config nonint get_i2c

0

lsmod | grep i2c

regmap_i2c 12288 1 rtc_pcf85063
i2c_dev 16384 0
i2c_mux_pinctrl 12288 0
i2c_mux 12288 1 i2c_mux_pinctrl
i2c_brcmstb 12288 0
i2c_bcm2835 16384 1

hwclock --verbose

hwclock from util-linux 2.38.1
System Time: 1753982389.603355
Trying to open: /dev/rtc0
Trying to open: /dev/rtc
Trying to open: /dev/misc/rtc
No usable clock interface found.
hwclock: Cannot access the Hardware Clock via any known method.

/boot/firmware/config.txt
dtparam=i2c_arm=on
#dtparam=i2s=on
#dtparam=spi=on
dtparam=i2c_vc=on

Nothing has changed except for software updates. Could you please take a look into this?

2

Same problem here after upgrading Raspbian to 6.12.34+rpt-rpi-v6.
I noticed that /dev/rtc and /dev/rtc0 are missing.
Any help?

PS: found this dmesg:
[ 22.037581] rtc_pcf85063: loading out-of-tree module taints kernel.

PPS: issue persists on Pi3 kernel 6.12.34+rpt-rpi-v7.

3

Not sure if something has changed in the kernel sources. I’ll try to recreate the issue later this week but currently only have a Pi3 and Pi5 available (but that might be irrelevant).

4

Same issue here with a Pi3. There seem to be changes with the latest kernel. I found multiple reports on this.

5

Had the same issue and though my battery just died. However, even the replacement did not do the magic…

After some poking around it turned out that the newer kernels obviously use a different path for the I2C device than the one which is included in the service file. For kernel 6.12 it is /sys/class/i2c-dev/i2c-1/device/new_device instead of /sys/class/i2c-adapter/i2c-1/new_device

So, just find your service file with sudo systemctl status rtc-pcf85063.serviceand edit it to use the correct path as mentioned above.