26 lines
992 B
ReStructuredText
26 lines
992 B
ReStructuredText
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==================
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SPI Device Drivers
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==================
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- ``include/nuttx/spi/spi.h``. All structures and APIs needed
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to work with SPI drivers are provided in this header file.
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- ``struct spi_ops_s``. Each SPI device driver must implement
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an instance of ``struct spi_ops_s``. That structure defines a
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call table with the following methods:
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- **Binding SPI Drivers**. SPI drivers are not normally directly
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accessed by user code, but are usually bound to another, higher
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level device driver. See for example,
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``int mmcsd_spislotinitialize(int minor, int slotno, FAR struct spi_dev_s *spi)``
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in ``drivers/mmcsd/mmcsd_spi.c``. In general, the binding
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sequence is:
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#. Get an instance of ``struct spi_dev_s`` from the
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hardware-specific SPI device driver, and
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#. Provide that instance to the initialization method of the
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higher level device driver.
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- **Examples**: ``drivers/loop.c``,
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``drivers/mmcsd/mmcsd_spi.c``, ``drivers/ramdisk.c``, etc.
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