[PATCH v2 15/27] drm/dp_mst: Cleanup drm_dp_send_link_address() a bit

Lyude Paul
2019-09-03T20:49:00Z

Declare local pointer to the drm_dp_link_address_ack_reply struct
instead of constantly dereferencing it through the union in
txmsg->reply. Then, invert the order of conditionals so we don't have to
do the bulk of the work inside them, and can wrap lines even less. Then
finally, rearrange variable declarations a bit.

Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
---
drivers/gpu/drm/drm_dp_mst_topology.c | 42 +++++++++++++++------------
1 file changed, 23 insertions(+), 19 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 2f88cc173500..d1610434a0cb 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -2398,9 +2398,9 @@ drm_dp_dump_link_address(struct drm_dp_link_address_ack_reply *reply)
static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
struct drm_dp_mst_branch *mstb)
{
- int len;
struct drm_dp_sideband_msg_tx *txmsg;
- int ret;
+ struct drm_dp_link_address_ack_reply *reply;
+ int i, len, ret;

txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
if (!txmsg)
@@ -2412,28 +2412,32 @@ static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
mstb->link_address_sent = true;
drm_dp_queue_down_tx(mgr, txmsg);

+ /* FIXME: Actually do some real error handling here */
ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
- if (ret > 0) {
- int i;
+ if (ret <= 0) {
+ DRM_ERROR("Sending link address failed with %d\n", ret);
+ goto out;
+ }
+ if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) {
+ DRM_ERROR("link address NAK received\n");
+ ret = -EIO;
+ goto out;
+ }

- if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) {
- DRM_DEBUG_KMS("link address nak received\n");
- } else {
- DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
- drm_dp_dump_link_address(&txmsg->reply.u.link_addr);
+ reply = &txmsg->reply.u.link_addr;
+ DRM_DEBUG_KMS("link address reply: %d\n", reply->nports);
+ drm_dp_dump_link_address(reply);

- drm_dp_check_mstb_guid(mstb, txmsg->reply.u.link_addr.guid);
+ drm_dp_check_mstb_guid(mstb, reply->guid);

- for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
- drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
- }
- drm_kms_helper_hotplug_event(mgr->dev);
- }
- } else {
- mstb->link_address_sent = false;
- DRM_DEBUG_KMS("link address failed %d\n", ret);
- }
+ for (i = 0; i < reply->nports; i++)
+ drm_dp_add_port(mstb, mgr->dev, &reply->ports[i]);
+
+ drm_kms_helper_hotplug_event(mgr->dev);

+out:
+ if (ret <= 0)
+ mstb->link_address_sent = false;
kfree(txmsg);
}

--
2.21.0