From: George Shen <george.shen@xxxxxxx> [Why] Passive DP40 cables were updated in the latest DP spec to support UHBR13.5 link rate. Current max link rate logic checks against the cable ID DPCD even for passive cables. [How] Ignore UHBR13.5 cable ID DPCD cap in get_max_link_rate logic. Reviewed-by: Wenjing Liu <wenjing.liu@xxxxxxx> Acked-by: Zaeem Mohamed <zaeem.mohamed@xxxxxxx> Signed-off-by: George Shen <george.shen@xxxxxxx> --- .../gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c index 1ff9876e3ca3..41bdadc585b3 100644 --- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c @@ -2124,7 +2124,8 @@ struct dc_link_settings dp_get_max_link_cap(struct dc_link *link) if (cable_max_link_rate < max_link_cap.link_rate) max_link_cap.link_rate = cable_max_link_rate; - if (!link->dpcd_caps.cable_id.bits.UHBR13_5_CAPABILITY) + if (!link->dpcd_caps.cable_id.bits.UHBR13_5_CAPABILITY && + link->dpcd_caps.cable_id.bits.CABLE_TYPE >= 2) is_uhbr13_5_supported = false; } -- 2.34.1