diff options
| author | Wayne Lin <Wayne.Lin@amd.com> | 2021-02-24 18:15:20 +0800 |
|---|---|---|
| committer | Lyude Paul <lyude@redhat.com> | 2021-02-24 13:10:07 -0500 |
| commit | 419e91ea3143bf26991442465ac64d9461e98d96 (patch) | |
| tree | f1796db66c7fd55aa1ceb3b021f1252e9c1e14f8 /drivers/gpu | |
| parent | 66922f850910056a2a3193388dd69b900e824717 (diff) | |
drm/dp_mst: Revise broadcast msg lct & lcr
[Why & How]
According to DP spec, broadcast message LCT equals to 1 and LCR equals
to 6. Current implementation is incorrect. Fix it.
In addition, revise a bit the hdr->rad handling to include broadcast
case.
Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Cc: stable@vger.kernel.org
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210224101521.6713-2-Wayne.Lin@amd.com
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/drm_dp_mst_topology.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 6dba74416841..2995e9c5976a 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -2827,10 +2827,15 @@ static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr, else hdr->broadcast = 0; hdr->path_msg = txmsg->path_msg; - hdr->lct = mstb->lct; - hdr->lcr = mstb->lct - 1; - if (mstb->lct > 1) - memcpy(hdr->rad, mstb->rad, mstb->lct / 2); + if (hdr->broadcast) { + hdr->lct = 1; + hdr->lcr = 6; + } else { + hdr->lct = mstb->lct; + hdr->lcr = mstb->lct - 1; + } + + memcpy(hdr->rad, mstb->rad, hdr->lct / 2); return 0; } |