# accessing i2c devices from userspace



## rockowitz (Sep 27, 2020)

I am the developer of ddcutil, a Linux utility for DDC communication. I am working on FreeBSD port.  On Linux, ddcutil reads from and writes to /dev/i2c-N devices, which are the video card I2C buses and exposed to userspace by the i2c-dev driver.

On FreeBSD, my understanding is that the corresponding devices are named /dev/iicN and are exposed by the iicbus driver.  I have loaded i2c drivers iicbus.ko, iic.ko, and video driver nvidia.ko, but the devices do not exist. What am I missing?

The kldstat output: 

`root@ritter:/ # kldstat
Id Refs Address Size Name
1 56 0xffffffff80200000 2448d90 kernel
2 1 0xffffffff8264a000 134d1e0 nvidia.ko
3 6 0xffffffff83998000 9698 linux_common.ko
4 2 0xffffffff839a2000 b7bd8 linux.ko
5 1 0xffffffff83a5a000 3910 iic.ko
6 2 0xffffffff83a5e000 6da0 iicbus.ko
7 1 0xffffffff83c21000 494c linprocfs.ko
8 1 0xffffffff83c26000 1eae linsysfs.ko
9 1 0xffffffff83c28000 88d8 tmpfs.ko
10 1 0xffffffff83c31000 18a0 uhid.ko
11 1 0xffffffff83c33000 2928 ums.ko
12 1 0xffffffff83c36000 1aa0 wmt.ko
13 1 0xffffffff83c38000 35b20 linux64.ko`



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