30 lines
1.3 KiB
Plaintext
30 lines
1.3 KiB
Plaintext
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I2C Slave API test
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##################
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This test verifies I2C slave driver implementations using two I2C
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controllers on a common bus. The test is supported by a test-specific
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driver that simulates an EEPROM with an I2C bus follower ("slave")
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interface. Data is pre-loaded into the simulated devices outside the
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I2C API, and the Zephyr application issues commands to one controller
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that are responded to by the simulated EEPROM connected through the
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other controller.
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In slightly more detail the test has these phases:
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* Use API specific to the simulated EEPROM to pre-populate the simulated
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devices with device-specific content.
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* Register each simulated EEPROM as a I2C follower device on a bus.
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* Issue commands on one bus controller (operating as the bus leader
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(master)) and verify that the data supplied by the other controller
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(as bus follower) match the expected values given the content known to
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be present on the simulated device.
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Transfer of commands from one bus controller to the other is
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accomplished by hardware through having the SCL (and SDA) signals
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shorted to join the two buses.
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Presence of this required hardware configuration is identified by the
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`i2c_bus_short` fixture. If the buses are not connected as required,
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or the controller driver has bugs, the test will fail one or more I2C
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transactions.
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