From: Cruise Hung Date: Tue, 10 Feb 2026 09:40:42 +0000 (+0800) Subject: drm/amd/display: Fix DPIA number and driver ID field issue X-Git-Tag: v7.1-rc1~167^2~31^2~97 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=cf1b9cbb5923a471c3b3bb6553da41004c75ebab;p=thirdparty%2Fkernel%2Flinux.git drm/amd/display: Fix DPIA number and driver ID field issue [Why] The DPIA number field is 6 bits in the spec. In dp_type, it only defines 5 bits. The driver ID is only 4 bits in the spec. [How] Set DPIA number field size to 6. And only update 4 bits for driver id. Reviewed-by: Meenakshikumar Somasundaram Signed-off-by: Cruise Hung Signed-off-by: Ivan Lipski Tested-by: Dan Wheeler Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/amd/display/dc/dc_dp_types.h b/drivers/gpu/drm/amd/display/dc/dc_dp_types.h index 5e3646b7550c1..9540f0ead2794 100644 --- a/drivers/gpu/drm/amd/display/dc/dc_dp_types.h +++ b/drivers/gpu/drm/amd/display/dc/dc_dp_types.h @@ -947,8 +947,8 @@ union dp_tun_cap_support { /* DPCD[0xE000E] DP_IN_ADAPTER_INFO register. */ union dpia_info { struct { - uint8_t dpia_num :5; - uint8_t rsvd :3; + uint8_t dpia_num :6; + uint8_t rsvd :2; } bits; uint8_t raw; }; diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia.c index 9b2f1a7da1d12..766b54631c798 100644 --- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia.c +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia.c @@ -71,7 +71,7 @@ enum dc_status dpcd_get_tunneling_device_data(struct dc_link *link) link->dpcd_caps.usb4_dp_tun_info.dpia_info.raw = dpcd_dp_tun_data[DP_IN_ADAPTER_INFO - DP_TUNNELING_CAPABILITIES_SUPPORT]; link->dpcd_caps.usb4_dp_tun_info.usb4_driver_id = - dpcd_dp_tun_data[DP_USB4_DRIVER_ID - DP_TUNNELING_CAPABILITIES_SUPPORT]; + dpcd_dp_tun_data[DP_USB4_DRIVER_ID - DP_TUNNELING_CAPABILITIES_SUPPORT] & 0x0F; if (link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dpia_bw_alloc) { status = core_link_read_dpcd(link, USB4_DRIVER_BW_CAPABILITY,