Hi! Did some work on adding PCA9538 support. This is again some 8-bit IO chip which is nearly identical to PCA9539 whose support already exists in kernel. I had just to modify slightly some stuff. I am going through it and will test it with hardware tomorrow but I need your comments! Not sure if my coding style etc fits your rules. So, please tell something. Patch is: http://www.jes.ee/~tonu/pca9539.patch Some example output: test:/usr/src/se95 # modprobe pca9539 test:/usr/src/se95 # !ca cat /sys/bus/i2c/devices/0-0073/name pca9538 test:/usr/src/se95 # cat /sys/bus/i2c/devices/0-0073/ bus/ direction0 driver/ input0 invert0 name output0 power/ test:/usr/src/se95 # cat /sys/bus/i2c/devices/0-0077/ bus/ direction1 input0 invert0 name output1 direction0 driver/ input1 invert1 output0 power/ test:/usr/src/se95 # cat /sys/bus/i2c/devices/0-0077/name pca9539 test:/usr/src/se95 # Tonu