Starting with DCE3 hardware, atom contains a general purpose
ProcessI2cChannelTransaction similar to ProcessAuxChannelTransaction.
Add an implementation using the atom tables for DCE3+ hardware.
This should be a little less CPU intensive than bit banging and
may work better in certain cases.
Enable it by setting the radeon hw_i2c module parameter to 1. E.g.,
radeon.hw_i2c=1
on the kernel command line in grub.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>