Hey Gerrit!

 GK> Any ideas what I might be missing here?

  $ zgrep PCA953 /proc/config.gz
  CONFIG_GPIO_PCA953X=m
  # CONFIG_GPIO_PCA953X_IRQ is not set
  CONFIG_LEDS_PCA9532=m
  # CONFIG_LEDS_PCA9532_GPIO is not set

Note that in my case they are turned off and therefore the kernel reports no device or chip found especially considering I don't have said chipset.  However even if I did it should still report no device or chip found.

Turning on the PCA953X (modular or builtin) should help your cause and is the only idea I can come up with not knowing if your kernel is actually PCA953X capable.

Life is good,
Maurice

... Meotud ana wat hw‘r se cwealm cyme¨, ¨e heonon of cy¨¨e gewite¨.
    Only God knows where plague goes when it departs from a place.
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