Troubleshooting • Re: PI5 miss to detect I2c devices where PI4 does.

I also have problems with the i2c interface after going to Pi 5 from Pi 3.
I read your message and that's what surprised me:
1. Your uname -a matches mine
pi@raspberrypi:~ $ uname -a
Linux raspberrypi 6.1.0-rpi7-rpi-2712 #1 SMP PREEMPT Debian 1:6.1.63-1+rpt1 (2023-11-24) aarch64 GNU/Linux

2. Your cpuinfo matches mine
pi@raspberrypi:~ $ grep Ras /proc/cpuinfo
Model: Raspberry Pi 5 Model B Rev 1.0

3. but I see you are running i2cdetect for 1. I have only i2c-11 and i2c-12 in my system. i2c-1 is not
Can you show your i2cdetect -l?

my is:
pi@raspberrypi:~ $ i2cdetect -l
i2c-11i2c 107d508200.i2c I2C adapter
i2c-12i2c 107d508280.i2c I2C adapter

just in case:
when I was debugging stable working with my custom board, I lowered the interface speed to 10 kHz:

dtparam=i2c_baudrate=10000

While I was writing the post, an idea came to me: suddenly my speed reduction is problem for i2c-1 detection.
I commented out a line
#dtparam=i2c_baudrate=10000
and a surprise:
pi@raspberrypi:~ $ i2cdetect -l
i2c-1i2c Synopsys DesignWare I2C adapter I2C adapter
i2c-11i2c 107d508200.i2c I2C adapter
i2c-12i2c 107d508280.i2c I2C adapter

Now there is i2c-1 Synopsys DesignWare I2C adapter

Statistics: Posted by poleg-on — Fri Jan 26, 2024 2:30 pm

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