[PATCH 1/3] drm/display/dp_mst: Don't validate port refs in drm_dp_check_and_send_link_address()

From: Lyude Paul
Date: Thu Jun 02 2022 - 16:18:32 EST


Drive-by cleanup, we don't need to validate the port references here as we
already previously went through the effort of refactoring things such that
we're guaranteed to be able to access ->mstb and ->port safely from
drm_dp_check_and_send_link_address(), since the only two places in the
codebase that drop an MST reference in such a way that it would remove it
from the topology are both protected under probe_lock.

Thanks for that, past Lyude!

Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx>
---
drivers/gpu/drm/display/drm_dp_mst_topology.c | 22 +++++--------------
1 file changed, 6 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c
index 67b3b9697da7..d84673b3294b 100644
--- a/drivers/gpu/drm/display/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c
@@ -2666,24 +2666,14 @@ static int drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mg
}

list_for_each_entry(port, &mstb->ports, next) {
- struct drm_dp_mst_branch *mstb_child = NULL;
-
- if (port->input || !port->ddps)
+ if (port->input || !port->ddps || !port->mstb)
continue;

- if (port->mstb)
- mstb_child = drm_dp_mst_topology_get_mstb_validated(
- mgr, port->mstb);
-
- if (mstb_child) {
- ret = drm_dp_check_and_send_link_address(mgr,
- mstb_child);
- drm_dp_mst_topology_put_mstb(mstb_child);
- if (ret == 1)
- changed = true;
- else if (ret < 0)
- return ret;
- }
+ ret = drm_dp_check_and_send_link_address(mgr, port->mstb);
+ if (ret == 1)
+ changed = true;
+ else if (ret < 0)
+ return ret;
}

return changed;
--
2.35.3