drm/amd/display: Allow constructing DCE6 link encoder without DDC

When the DDC channel ID is set to CHANNEL_ID_UNKNOWN,
pass NULL to the AUX regs array.

This is necessary to support embedded connectors without DDC.

Fixes: 7c15fd86aaec ("drm/amd/display: dc/dce: add initial DCE6 support (v10)")
Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/5192
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 38a70e50b22a188ff601740d64dd75f46213121f)

diff --git a/drivers/gpu/drm/amd/display/dc/resource/dce60/dce60_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dce60/dce60_resource.c
index 6a25dcfcdf17eaee5bb195792a3e48693bcce222..d2d56a1c4b8b3a5ecae31ba1c08981371db66e99 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/resource/dce60/dce60_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dce60/dce60_resource.c
@@ -753,7 +753,8 @@ static struct link_encoder *dce60_link_encoder_create(
                                     enc_init_data,
                                     &link_enc_feature,
                                     &link_enc_regs[link_regs_id],
-                                    &link_enc_aux_regs[enc_init_data->channel - 1],
+                                    enc_init_data->channel == CHANNEL_ID_UNKNOWN ?
+                                    NULL : &link_enc_aux_regs[enc_init_data->channel - 1],
                                     enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs) ?
                                     NULL : &link_enc_hpd_regs[enc_init_data->hpd_source]);
        return &enc110->base;