drm/amd/display: Add KUnit tests for HDCP DDC link adapters

Expose the mod_hdcp DDC adapter callbacks for KUnit and add tests:

lp_write_i2c / lp_read_i2c / lp_write_dpcd / lp_read_dpcd use recording
fake i2c and DP aux backends to assert the built payloads (write flag,
address, length, buffer, and the read offset-then-data sequence), plus
failure when the connector is missing.

lp_atomic_write_poll_read_i2c / lp_atomic_write_poll_read_aux cover the
hardware-free early returns (NULL link and a payload too large to convert);
the success path submits fused-IO to the DMCUB and is out of reach for a
unit test.

Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Signed-off-by: Fangzhi Zuo <jerry.zuo@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

0 files changed, 0 insertions, 0 deletions