Hello all, Maybe some will be able to help a bit. I'm running 2 Raspberries 3B+, with the same old CentOS image, freshly prepared. Both run raspberrypi2-kernel 4.19.xx Both Raspberry have a hat, with a valid EEPROM. On both, the application I'm in charge of, has R/W access to /sys/class/i2c-adapter/i2c-3/3-0050/eeprom On one Raspberry, I update the kernel and only the kernel (yum update raspberrypi2-kernel) and I come to 5.4.42. After reboot, the whole content of /sys/class has changed, regarding I2C. 4.19.94: [root at Raspberry-DD7BD7 OLD ~]$ ls -al /sys/bus/i2c/devices/ total 0 drwxr-xr-x. 2 root root 0 Jan 1 1970 . drwxr-xr-x. 4 root root 0 Jan 1 1970 .. lrwxrwxrwx. 1 root root 0 Jan 1 1970 3-0050 -> ../../../devices/platform/ffffffff.i2c/i2c-3/3-0050 lrwxrwxrwx. 1 root root 0 Jan 1 1970 i2c-3 -> ../../../devices/platform/ffffffff.i2c/i2c-3 [root at Raspberry-DD7BD7 OLD ~]$ ls -al /sys/bus/i2c/devices/3-0050/eeprom 5.4.42: [root at CertifBox-8AC500 OLD ~]$ ls -al /sys/class/i2c-adapter/ total 0 drwxr-xr-x. 2 root root 0 Jan 1 1970 . drwxr-xr-x. 54 root root 0 Jan 1 1970 .. lrwxrwxrwx. 1 root root 0 Jun 15 22:53 i2c-11 -> ../../devices/platform/ffffffff.i2c/i2c-11 [root at CertifBox-8AC500 OLD ~]$ Any idea where I can find this EEPROM file ? A module option, maybe ? Regards, Stephan.