SpiBusDriver

public interface SpiBusDriver
implements Closeable

com.google.android.things.userdriver.pio.SpiBusDriver

SPI user driver. A SpiBusDriver defines an entire SPI bus with multiple possible devices attached to it. Individual SpiDevice objects can be opened and closed on the bus independently.

Summary

Public methods

default void close()

Closes the bus.

abstract SpiDevice createSpiDevice(String chipSelect)

Creates an SPI device on the bus.

abstract String[] getChipSelectNames()

Returns the array of supported chip selects.

default void open()

Opens the bus.

Inherited methods

From interface java.io.Closeable
From interface java.lang.AutoCloseable

Public methods

close

void close ()

Closes the bus. This will be called just after the last device is closed by its owner. Any resources that need to be cleaned up can be done so here. This method may throw IOException to indicate I/O failure, but the bus will still be considered closed and may attempt to be re-opened in the future.

Throws
IOException on I/O failure; the bus will still be considered closed.

createSpiDevice

SpiDevice createSpiDevice (String chipSelect)

Creates an SPI device on the bus. This will be called when ownership of a single SPI device is requested. The driver should create and return a new SpiDevice object. The driver manager will internally make sure that no other SPI device is opened at this chip select until the returned device is closed.

Parameters
chipSelect String: the name of the chip select to open the device with.
Returns
SpiDevice A new SpiDevice connected to the given address.
Throws
IOException on I/O failure; the SPI slave device will remain unowned.

getChipSelectNames

String[] getChipSelectNames ()

Returns the array of supported chip selects. Chip select names can be arbitrary strings. The resulting I/O names will be {bus_name}.{cs_name}.

Returns
String[] An array of string names.

open

void open ()

Opens the bus. This will be called just before the first device is requested on this bus. The driver may do any initialization needed to configure the bus for use here.

Throws
IOException on I/O failure; the bus will remain closed.