[PATCH v2 0/5] tests/kms_writeback: Add clone mode subtest

[Jessica Zhang]

Add a subtest that will iterate through all pairs of
non-writeback and writeback cloned outputs and dump the writeback
framebuffer for each pair.

This series includes:

- Fixes for properly cleaning up the kms_writeback state and forcing a
  modeset after igt_display_require() to prevent commit failures when
  the writeback mode is the same as the primary display mode
- Adjust the duplicate pipe check in igt_display_refresh() to allow for
  combinations of valid clones
- Moving the writeback dump to its own subtest
- Adding a subtest to dump all writeback/non-writeback cloned pairs

To dump the clone mode buffer, run the following command:

IGT_FRAME_DUMP_PATH=<dump path> FRAME_PNG_FILE_NAME=<file name> \
	./build/tests/kms_writeback [--run-subtest dump-valid-clones] \
	-dc <primary display mode>

This will output a file named <file name>-encoder<writeback encoder
id>-encoder<primary display encoder id>

---
Changes in v2:
- Corrected author email
- Link to v1: https://lore.kernel.org/r/20240828-igt-cwb-v1-0-48aee421fc97@quicinc.com

---
Jessica Zhang (5):
      tests/kms_writeback: clear writeback properties in teardown path
      lib/igt_kms: Add helper to get encoder index
      lib/igt_kms: loosen duplicate check in igt_display_refresh
      tests/kms_writeback: Disable all outputs after igt_display_require()
      tests/kms_writeback: Add dump for valid clone mode

 lib/igt_kms.c         | 57 +++++++++++++++++++++++++++++------
 lib/igt_kms.h         |  2 ++
 tests/kms_setmode.c   | 14 ++-------
 tests/kms_writeback.c | 83 +++++++++++++++++++++++++++++++++++++++++++--------
 4 files changed, 122 insertions(+), 34 deletions(-)
---
base-commit: 3b6b2d238e864ff1af9e33159d3bbf4b7f01d86d
change-id: 20240827-igt-cwb-23fd81d3a7a4

Best regards,
-- 
Jessica Zhang <quic_jesszhan at quicinc.com>