I really wanted to use user-space SMBus code for the MLX90614 sensor. Finding code to access the Raspberry Pi's I2C master directly was easy, but I couldn't find a fix for the kernel. So I fixed it. The changes are in bcm2708_i2c_master_xfer() of i2c-bcm2708.c.
Here is the test program I used:
I also tested the BMP085 using the kernel's support for it, and that still works.