[PATCH v2 12/27] drm/dp_mst: Refactor drm_dp_mst_handle_up_req()

From: Lyude Paul
Date: Tue Sep 03 2019 - 16:49:13 EST


There's a couple of changes here, so to summarize:

* Remove the big ugly mgr->up_req_recv.have_eomt conditional to save on
indenting
* Store &mgr->up_req_recv.initial_hdr in a variable so we don't keep
going over 80 character long lines
* De-duplicate code for calling drm_dp_send_up_ack_reply() and getting
the MSTB via it's GUID
* Remove all of the duplicate calls to memset() and just use a goto
instead
* Actually do line wrapping
* Remove the unnecessary if (mstb) check before calling
drm_dp_mst_topology_put_mstb() - we are guaranteed to always have
mstb != NULL at that point in the function

Cc: Juston Li <juston.li@xxxxxxxxx>
Cc: Imre Deak <imre.deak@xxxxxxxxx>
Cc: Ville SyrjÃlà <ville.syrjala@xxxxxxxxxxxxxxx>
Cc: Harry Wentland <hwentlan@xxxxxxx>
Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx>
---
drivers/gpu/drm/drm_dp_mst_topology.c | 75 ++++++++++++++-------------
1 file changed, 38 insertions(+), 37 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index b44d3696c09a..64487098158a 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -3246,68 +3246,69 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
{
struct drm_dp_sideband_msg_req_body msg;
+ struct drm_dp_sideband_msg_hdr *hdr = &mgr->up_req_recv.initial_hdr;
struct drm_dp_mst_branch *mstb = NULL;
+ const u8 *guid;
bool seqno;

- if (!drm_dp_get_one_sb_msg(mgr, true)) {
- memset(&mgr->up_req_recv, 0,
- sizeof(struct drm_dp_sideband_msg_rx));
- return 0;
- }
+ if (!drm_dp_get_one_sb_msg(mgr, true))
+ goto out;

if (!mgr->up_req_recv.have_eomt)
return 0;

- if (!mgr->up_req_recv.initial_hdr.broadcast) {
- mstb = drm_dp_get_mst_branch_device(mgr,
- mgr->up_req_recv.initial_hdr.lct,
- mgr->up_req_recv.initial_hdr.rad);
+ if (!hdr->broadcast) {
+ mstb = drm_dp_get_mst_branch_device(mgr, hdr->lct, hdr->rad);
if (!mstb) {
- DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
- memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
- return 0;
+ DRM_DEBUG_KMS("Got MST reply from unknown device %d\n",
+ hdr->lct);
+ goto out;
}
}

- seqno = mgr->up_req_recv.initial_hdr.seqno;
+ seqno = hdr->seqno;
drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);

- if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
- drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false);
+ if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY)
+ guid = msg.u.conn_stat.guid;
+ else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY)
+ guid = msg.u.resource_stat.guid;
+ else
+ goto out;

- if (!mstb)
- mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.conn_stat.guid);
+ drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno,
+ false);

+ if (!mstb) {
+ mstb = drm_dp_get_mst_branch_device_by_guid(mgr, guid);
if (!mstb) {
- DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
- memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
- return 0;
+ DRM_DEBUG_KMS("Got MST reply from unknown device %d\n",
+ hdr->lct);
+ goto out;
}
+ }

+ if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
drm_dp_update_port(mstb, &msg.u.conn_stat);

- DRM_DEBUG_KMS("Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n", msg.u.conn_stat.port_number, msg.u.conn_stat.legacy_device_plug_status, msg.u.conn_stat.displayport_device_plug_status, msg.u.conn_stat.message_capability_status, msg.u.conn_stat.input_port, msg.u.conn_stat.peer_device_type);
- drm_kms_helper_hotplug_event(mgr->dev);
+ DRM_DEBUG_KMS("Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n",
+ msg.u.conn_stat.port_number,
+ msg.u.conn_stat.legacy_device_plug_status,
+ msg.u.conn_stat.displayport_device_plug_status,
+ msg.u.conn_stat.message_capability_status,
+ msg.u.conn_stat.input_port,
+ msg.u.conn_stat.peer_device_type);

+ drm_kms_helper_hotplug_event(mgr->dev);
} else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
- drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false);
- if (!mstb)
- mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.resource_stat.guid);
-
- if (!mstb) {
- DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
- memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
- return 0;
- }
-
- DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
+ DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n",
+ msg.u.resource_stat.port_number,
+ msg.u.resource_stat.available_pbn);
}

- if (mstb)
- drm_dp_mst_topology_put_mstb(mstb);
-
+ drm_dp_mst_topology_put_mstb(mstb);
+out:
memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
-
return 0;
}

--
2.21.0