drm/amd/display: check phy dpalt lane count config

[Why]
Type-c PHY config is not align with dpcd lane count.
When those values didn't match, it cause driver do
link training with 4 lane but phy only can output 2 lane.
The link trainig always fail.

[How]
1. Modify get_max_link_cap function. According DPALT_DP4
to update max lane count.
2. Add dp_mst_verify_link_cap to handle MST case because
we didn't call dp_mst_verify_link_cap for MST case.

Signed-off-by: Lewis Huang <Lewis.Huang@amd.com>
Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/inc/hw/link_encoder.h b/drivers/gpu/drm/amd/display/dc/inc/hw/link_encoder.h
index abb4e4237fb6..b21909216fb6 100644
--- a/drivers/gpu/drm/amd/display/dc/inc/hw/link_encoder.h
+++ b/drivers/gpu/drm/amd/display/dc/inc/hw/link_encoder.h
@@ -184,6 +184,10 @@ struct link_encoder_funcs {
 	bool (*fec_is_active)(struct link_encoder *enc);
 #endif
 	bool (*is_in_alt_mode) (struct link_encoder *enc);
+
+	void (*get_max_link_cap)(struct link_encoder *enc,
+		struct dc_link_settings *link_settings);
+
 	enum signal_type (*get_dig_mode)(
 		struct link_encoder *enc);
 };