This small series adds a few kunit tests for the new DRM bridge allocation
flow, based on the recently introduced devm_drm_bridge_alloc() [0].
It is part of the work towards removal of bridges from a still existing DRM
pipeline without use-after-free.
The steps in the grand plan [1] are:
1. ➜ add refcounting to DRM bridges (struct drm_bridge)
2. handle gracefully atomic updates during bridge removal
3. avoid DSI host drivers to have dangling pointers to DSI devices
4. finish the hotplug bridge work, removing the "always-disconnected"
connector, moving code to the core and potentially removing the
hotplug-bridge itself (this needs to be clarified as points 1-3 are
developed)
This series is part of step 1 of the grand plan.
Current tasks in step 1 of the grand plan:
A. ✔ add new alloc API and refcounting -> (now in drm-misc-next)
B. … convert all bridge drivers to new API (in progress)
C. ➜ kunit tests (this series)
D. after (B), add get/put to drm_bridge_add/remove() + attach/detech()
E. after (B), convert accessors; this is a large work and can be done
in chunks
F. debugfs improvements
[0]
https://gitlab.freedesktop.org/drm/misc/kernel/-/commit/0cc6aadd7fc1e629b715ea3d1ba537ef2da95eec
[1]
https://lore.kernel.org/lkml/20250206-hotplug-drm-bridge-v6-0-9d6f2c9c3...@bootlin.com/t/#u
Signed-off-by: Luca Ceresoli <luca.ceres...@bootlin.com>
---
Changes in v8:
- Remove documentation patch
- Add patch to convert existing kunit tests to use devm_drm_bridge_alloc()
- Add tests for bridge deallocation (based on adding a .destroy callback)
- Link to v7:
https://lore.kernel.org/r/20250409-drm-bridge-alloc-doc-test-v7-0-a3ca4b975...@bootlin.com
---
Luca Ceresoli (3):
drm/tests: bridge: convert to devm_drm_bridge_alloc() API
dmr/bridge: add a .destroy func
drm/tests: bridge: add KUnit tests for devm_drm_bridge_alloc()
drivers/gpu/drm/drm_bridge.c | 2 +
drivers/gpu/drm/tests/drm_bridge_test.c | 179 +++++++++++++++++++++++++-------
include/drm/drm_bridge.h | 10 ++
3 files changed, 151 insertions(+), 40 deletions(-)
---
base-commit: aec8a40228acb385d60feec59b54573d307e60f3
change-id: 20250408-drm-bridge-alloc-doc-test-267df0def880
Best regards,
--
Luca Ceresoli <luca.ceres...@bootlin.com>
