By default, drmModeGetFB2() behaves as-if the kernel didn't support
the IOCTL. That way we don't need to update all tests to set sensible
FB info.
If a test is specifically interested in testing drmModeGetFB2()
behavior, it can call liftoff_mock_drm_set_fb_info().
This allows to mimick i915's requirement of failing all commits
which don't have the primary plane enabled.
We could expand our test matrix to test with the param *and* without
it, but since enabling the param just makes the atomic check more
strict there's no real benefit of doing that. Enabling the param
can only make tests fail more often, not the other way around.
This fixes a misunderstanding of the DRM API. Only a regular commit applies
properties.
Fixes: b16078769e ("test/libdrm_mock: a test-only commit applies properties")
The previous mock library assumed the DRM client would always set all
properties in the atomic request. However, if a previous test-only commit
has set a property, there's no need to set it again.
Accomodate for this in libdrm_mock. This will be useful when we'll skip
setting properties that haven't changed in libliftoff.
References: https://github.com/emersion/libliftoff/issues/37
When testing the library, the libdrm dependency is swapped with a mock libdrm.
The test sets up the mock libdrm's internal state and then runs the test.