30 lines
1.3 KiB
Plaintext
30 lines
1.3 KiB
Plaintext
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Fixed Regulator
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###############
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This application tests the fixed regulator driver in multiple
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configurations. Like the GPIO driver test it requires that two GPIO
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pins be shorted so that changes made to the state of one can be verified
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by inspecting the other.
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Unlike the GPIO driver test the behavior of a fixed regulator depends
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heavily on the properties specified in its devicetree node. The
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``compatible`` property causes the underlying driver implementation to
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select between one that supports asynchronous transitions and an
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optimized one synchronous transitions. The initial state of the
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regulator, whether it can be changed, and enforced transition delays are
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all controlled by devicetree properties.
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Because the regulator can only be configured at system startup it is
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necessary to test varying configurations in separate test sessions. The
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``testcase.yaml`` file provides a variety of flags intended to cover the
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various behaviors.
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Only boards for which an overlay is present can pass this test. Boards
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without an overlay, or for which the required wiring is not provided,
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will fail with an error like this:
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Assertion failed at ../src/main.c:182: test_preconditions: (precheck not equal to PC_OK)
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precheck failed: active check failed
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No special build options are required to make use of the overlay.
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