diff options
Diffstat (limited to 'drivers/gpu/drm/display/drm_dp_mst_topology.c')
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_mst_topology.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c index 1475aa95ab6b..bcf3a33123be 100644 --- a/drivers/gpu/drm/display/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c @@ -3941,6 +3941,34 @@ drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up, return true; } +static int get_msg_request_type(u8 data) +{ + return data & 0x7f; +} + +static bool verify_rx_request_type(struct drm_dp_mst_topology_mgr *mgr, + const struct drm_dp_sideband_msg_tx *txmsg, + const struct drm_dp_sideband_msg_rx *rxmsg) +{ + const struct drm_dp_sideband_msg_hdr *hdr = &rxmsg->initial_hdr; + const struct drm_dp_mst_branch *mstb = txmsg->dst; + int tx_req_type = get_msg_request_type(txmsg->msg[0]); + int rx_req_type = get_msg_request_type(rxmsg->msg[0]); + char rad_str[64]; + + if (tx_req_type == rx_req_type) + return true; + + drm_dp_mst_rad_to_str(mstb->rad, mstb->lct, rad_str, sizeof(rad_str)); + drm_dbg_kms(mgr->dev, + "Got unexpected MST reply, mstb: %p seqno: %d lct: %d rad: %s rx_req_type: %s (%02x) != tx_req_type: %s (%02x)\n", + mstb, hdr->seqno, mstb->lct, rad_str, + drm_dp_mst_req_type_str(rx_req_type), rx_req_type, + drm_dp_mst_req_type_str(tx_req_type), tx_req_type); + + return false; +} + static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr) { struct drm_dp_sideband_msg_tx *txmsg; @@ -3970,6 +3998,9 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr) goto out_clear_reply; } + if (!verify_rx_request_type(mgr, txmsg, msg)) + goto out_clear_reply; + drm_dp_sideband_parse_reply(mgr, msg, &txmsg->reply); if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { |