/*

* Copyright (c) Steven P. Goldsmith. All rights reserved.

*/

package com.codeferm.periphery;

import static com.codeferm.periphery.Common.MAX_CHAR_ARRAY_LEN;

import static com.codeferm.periphery.Common.free;

import static com.codeferm.periphery.Common.jString;

import static com.codeferm.periphery.Common.memMove;

import org.fusesource.hawtjni.runtime.ClassFlag;

import static org.fusesource.hawtjni.runtime.FieldFlag.CONSTANT;

import org.fusesource.hawtjni.runtime.JniClass;

import org.fusesource.hawtjni.runtime.JniField;

import org.fusesource.hawtjni.runtime.JniMethod;

import org.fusesource.hawtjni.runtime.Library;

import static org.fusesource.hawtjni.runtime.MethodFlag.CONSTANT_INITIALIZER;

/**

* c-periphery GPIO wrapper methods for Linux userspace character device gpio-cdev and sysfs GPIOs.

*

* @author Steven P. Goldsmith

* @version 1.0.0

* @since 1.0.0

*/

@JniClass

public class Gpio implements AutoCloseable {

/**

* gpioPoll returned event.

*/

public static final int GPIO_POLL_EVENT = 1;

/**

* gpioPoll timeout.

*/

public static final int GPIO_POLL_TIMEOUT = 0;

/**

* Function was successful.

*/

public static final int GPIO_SUCCESS = 0;

/**

* java-periphery library.

*/

private static final Library LIBRARY = new Library("java-periphery", Gpio.class);

/**

* GPIO handle.

*/

final private long handle;

/**

* Gpio config struct.

*/

final private GpioConfig config;

/**

* Load library.

*/

static {

LIBRARY.load();

init();

}

/**

* Load constants.

*/

@JniMethod(flags = {CONSTANT_INITIALIZER})

private static native void init();

/**

* Error constants.

*/

@JniField(flags = {CONSTANT})

public static int GPIO_ERROR_ARG;

@JniField(flags = {CONSTANT})

public static int GPIO_ERROR_OPEN;

@JniField(flags = {CONSTANT})

public static int GPIO_ERROR_NOT_FOUND;

@JniField(flags = {CONSTANT})

public static int GPIO_ERROR_QUERY;

@JniField(flags = {CONSTANT})

public static int GPIO_ERROR_CONFIGURE;

@JniField(flags = {CONSTANT})

public static int GPIO_ERROR_UNSUPPORTED;

@JniField(flags = {CONSTANT})

public static int GPIO_ERROR_INVALID_OPERATION;

@JniField(flags = {CONSTANT})

public static int GPIO_ERROR_IO;

@JniField(flags = {CONSTANT})

public static int GPIO_ERROR_CLOSE;

/**

* Direction constants.

*/

@JniField(flags = {CONSTANT})

public static int GPIO_DIR_IN;

@JniField(flags = {CONSTANT})

public static int GPIO_DIR_OUT;

@JniField(flags = {CONSTANT})

public static int GPIO_DIR_OUT_LOW;

@JniField(flags = {CONSTANT})

public static int GPIO_DIR_OUT_HIGH;

/**

* Edge constants.

*/

@JniField(flags = {CONSTANT})

public static int GPIO_EDGE_NONE;

@JniField(flags = {CONSTANT})

public static int GPIO_EDGE_RISING;

@JniField(flags = {CONSTANT})

public static int GPIO_EDGE_FALLING;

@JniField(flags = {CONSTANT})

public static int GPIO_EDGE_BOTH;

/**

* Bias constants.

*/

@JniField(flags = {CONSTANT})

public static int GPIO_BIAS_DEFAULT;

@JniField(flags = {CONSTANT})

public static int GPIO_BIAS_PULL_UP;

@JniField(flags = {CONSTANT})

public static int GPIO_BIAS_PULL_DOWN;

@JniField(flags = {CONSTANT})

public static int GPIO_BIAS_DISABLE;

/**

* Drive constants.

*/

@JniField(flags = {CONSTANT})

public static int GPIO_DRIVE_DEFAULT;

@JniField(flags = {CONSTANT})

public static int GPIO_DRIVE_OPEN_DRAIN;

@JniField(flags = {CONSTANT})

public static int GPIO_DRIVE_OPEN_SOURCE;

/**

* gpio_config struct as Java object. Allow fluent style to set members.

*/

@JniClass(name = "gpio_config_t", flags = {ClassFlag.STRUCT, ClassFlag.TYPEDEF})

public static class GpioConfig {

static {

LIBRARY.load();

init();

}

@JniMethod(flags = {CONSTANT_INITIALIZER})

private static native void init();

@JniField(flags = {CONSTANT}, accessor = "sizeof(gpio_config_t)")

private static int SIZEOF;

private int direction;

private int edge;

private int bias;

private int drive;

private boolean inverted;

private long label;

public static int getSIZEOF() {

return SIZEOF;

}

public static void setSIZEOF(int SIZEOF) {

GpioConfig.SIZEOF = SIZEOF;

}

public int getDirection() {

return direction;

}

public GpioConfig setDirection(final int direction) {

this.direction = direction;

return this;

}

public int getEdge() {

return edge;

}

public GpioConfig setEdge(final int edge) {

this.edge = edge;

return this;

}

public int getBias() {

return bias;

}

public GpioConfig setBias(final int bias) {

this.bias = bias;

return this;

}

public int getDrive() {

return drive;

}

public GpioConfig setDrive(final int drive) {

this.drive = drive;

return this;

}

public boolean isInverted() {

return inverted;

}

public GpioConfig setInverted(final boolean inverted) {

this.inverted = inverted;

return this;

}

public long getLabel() {

return label;

}

public GpioConfig setLabel(final long label) {

this.label = label;

return this;

}

}

/**

* Open the character device GPIO with the specified GPIO line and direction at the specified character device GPIO chip path.

*

* @param path GPIO chip character device path.

* @param line GPIO line number.

* @param direction One of the direction values.

*/

public Gpio(final String path, final int line, final int direction) {

// Config not used

config = null;

// Allocate handle

handle = gpioNew();

if (handle == 0) {

throw new RuntimeException("Handle cannot be NULL");

}

// Open line

if (gpioOpen(handle, path, line, direction) != GPIO_SUCCESS) {

// Free handle before throwing exception

gpioFree(handle);

throw new RuntimeException(gpioErrMessage(handle));

}

}

/**

* Open the character device GPIO with the specified GPIO name and direction at the specified character device GPIO chip path

* (e.g. /dev/gpiochip0).

*

* @param path GPIO chip character device path.

* @param name GPIO line name.

* @param direction One of the direction values.

*/

public Gpio(final String path, final String name, final int direction) {

// Config not used

config = null;

// Allocate handle

handle = gpioNew();

if (handle == 0) {

throw new RuntimeException("Handle cannot be NULL");

}

// Open line

if (gpioOpenName(handle, path, name, direction) != GPIO_SUCCESS) {

// Free handle before throwing exception

gpioFree(handle);

throw new RuntimeException(gpioErrMessage(handle));

}

}

/**

* Open the character device GPIO with the specified GPIO line and configuration at the specified character device GPIO chip

* path (e.g. /dev/gpiochip0).

*

* @param path GPIO chip character device path.

* @param line GPIO line number.

* @param config Configuration struct.

*/

public Gpio(final String path, final int line, final GpioConfig config) {

this.config = config;

// Allocate handle

handle = gpioNew();

if (handle == 0) {

// Deallocate label before throwing exception

if (config.getLabel() != 0) {

free(config.getLabel());

}

throw new RuntimeException("Handle cannot be NULL");

}

// Open line

if (gpioOpenAdvanced(handle, path, line, config) != GPIO_SUCCESS) {

// Free handle before throwing exception

gpioFree(handle);

// Deallocate label before throwing exception

if (config.getLabel() != 0) {

free(config.getLabel());

}

throw new RuntimeException(gpioErrMessage(handle));

}

}

/**

* Open the character device GPIO with the specified GPIO name and configuration at the specified character device GPIO chip

* path (e.g. /dev/gpiochip0).

*

* @param path GPIO chip character device path.

* @param name GPIO line name.

* @param config Configuration struct.

*/

public Gpio(final String path, final String name, final GpioConfig config) {

this.config = config;

// Allocate handle

handle = gpioNew();

if (handle == 0) {

// Deallocate label before throwing exception

if (config.getLabel() != 0) {

free(config.getLabel());

}

throw new RuntimeException("Handle cannot be NULL");

}

// Open line

if (gpioOpenNameAdvanced(handle, path, name, config) != GPIO_SUCCESS) {

// Free handle before throwing exception

gpioFree(handle);

// Deallocate label before throwing exception

if (config.getLabel() != 0) {

free(config.getLabel());

}

throw new RuntimeException(gpioErrMessage(handle));

}

}

/**

* Open the sysfs GPIO with the specified line and direction.

*

* @param line GPIO line number.

* @param direction One of the direction values.

*/

public Gpio(final int line, final int direction) {

// Config not used

config = null;

// Allocate handle

handle = gpioNew();

if (handle == 0) {

throw new RuntimeException("Handle cannot be NULL");

}

// Open line

if (gpioOpenSysfs(handle, line, direction) != GPIO_SUCCESS) {

// Free handle before throwing exception

gpioFree(handle);

throw new RuntimeException(gpioErrMessage(handle));

}

}

/**

* Close handle, free handle and free line label if allocated.

*/

@Override

public void close() {

// Close handle

gpioClose(handle);

// Free handle

gpioFree(handle);

// Deallocate label

if (config != null && config.getLabel() != 0) {

free(config.getLabel());

}

}

/**

* Handle accessor.

*

* @return Handle.

*/

public long getHandle() {

return handle;

}

/**

* Config accessor.

*

* @return Config.

*/

public GpioConfig getConfig() {

return config;

}

/**

* Allocate a GPIO handle. Returns a valid handle on success, or NULL on failure.

*

* @return A valid handle on success, or NULL on failure.

*/

@JniMethod(accessor = "gpio_new")

public static final native long gpioNew();

/**

* Open the character device GPIO with the specified GPIO line and direction at the specified character device GPIO chip path.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param path GPIO chip character device path.

* @param line GPIO line number.

* @param direction One of the direction values.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_open")

public static native int gpioOpen(long gpio, String path, int line, int direction);

/**

* Open the character device GPIO with the specified GPIO name and direction at the specified character device GPIO chip path

* (e.g. /dev/gpiochip0).

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param path GPIO chip character device path.

* @param name GPIO line name.

* @param direction One of the direction values.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_open_name")

public static native int gpioOpenName(long gpio, String path, String name, int direction);

/**

* Open the character device GPIO with the specified GPIO line and configuration at the specified character device GPIO chip

* path (e.g. /dev/gpiochip0).

*

* gpio should be a valid pointer to an allocated GPIO handle structure. path is the GPIO chip character device path. line is

* the GPIO line number. config should be a valid pointer to a gpio_config_t structure with valid values. label can be NULL for

* a default consumer label.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param path GPIO chip character device path.

* @param line GPIO line number.

* @param config Configuration struct.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_open_advanced")

public static native int gpioOpenAdvanced(long gpio, String path, int line, GpioConfig config);

/**

* Open the character device GPIO with the specified GPIO name and configuration at the specified character device GPIO chip

* path (e.g. /dev/gpiochip0).

*

* gpio should be a valid pointer to an allocated GPIO handle structure. path is the GPIO chip character device path. name is

* the GPIO line name. config should be a valid pointer to a gpio_config_t structure with valid values. label can be NULL for a

* default consumer label.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param path GPIO chip character device path.

* @param name GPIO line name.

* @param config Configuration struct.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_open_name_advanced")

public static native int gpioOpenNameAdvanced(long gpio, String path, String name, GpioConfig config);

/**

* Open the sysfs GPIO with the specified line and direction.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param line GPIO line number.

* @param direction One of the direction values.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_open_sysfs")

public static native int gpioOpenSysfs(long gpio, int line, int direction);

/**

* Read the state of the GPIO into value.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param value Pointer to an allocated bool.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_read")

public static native int gpioRead(long gpio, boolean[] value);

/**

* Set the state of the GPIO to value.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param value True of false.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_write")

public static native int gpioWrite(long gpio, boolean value);

/**

* Poll a GPIO for the edge event configured with gpio_set_edge(). For character device GPIOs, the edge event should be consumed

* with gpio_read_event(). For sysfs GPIOs, the edge event should be consumed with gpio_read().

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param timeoutMs Positive number for a timeout in milliseconds, 0 for a non-blocking poll, or a negative number for a

* blocking poll.

* @return 1 on success (an edge event occurred), 0 on timeout, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_poll")

public static native int gpioPoll(long gpio, int timeoutMs);

/**

* Close the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_close")

public static native int gpioClose(long gpio);

/**

* Free a GPIO handle.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

*/

@JniMethod(accessor = "gpio_free")

public static native void gpioFree(long gpio);

/**

* Read the edge event that occurred with the GPIO. This method is intended for use with character device GPIOs and is

* unsupported by sysfs GPIOs.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param edge Pointer to an allocated int.

* @param timestamp Pointer to an allocated long.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_read_event")

public static native int gpioReadEvent(long gpio, int[] edge, long[] timestamp);

/**

* Poll multiple GPIOs for an edge event configured with gpio_set_edge(). For character device GPIOs, the edge event should be

* consumed with gpio_read_event(). For sysfs GPIOs, the edge event should be consumed with gpio_read().

*

* @param gpios A valid pointer to a size count array of GPIO handles opened with one of the gpio_open*() functions.

* @param count Number of gpio pointers.

* @param timeoutMs Positive number for a timeout in milliseconds, 0 for a non-blocking poll, or a negative number for a

* blocking poll.

* @param gpiosReady is an optional pointer to a size count array of bool that will be populated with true for the corresponding

* GPIO in the gpios array if an edge event occurred, or false if none occurred.

* @return Number of GPIOs for which an edge event occurred, 0 on timeout, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_poll_multiple")

public static native int gpioPollMultiple(long[] gpios, int count, int timeoutMs, boolean[] gpiosReady);

/**

* Get the configured direction of the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param direction Pointer to an allocated int.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_get_direction")

public static native int gpioGetDirection(long gpio, int[] direction);

/**

* Get the configured interrupt edge of the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param edge Pointer to an allocated int.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_get_edge")

public static native int gpioGetEdge(long gpio, int[] edge);

/**

* Get the configured line bias of the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param bias

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_get_bias")

public static native int gpioGetBias(long gpio, int[] bias);

/**

* Get the configured line drive of the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param drive

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_get_drive")

public static native int gpioGetDrive(long gpio, int[] drive);

/**

* Get the configured line inverted of the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param inverted Active low.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_get_inverted")

public static native int gpioGetInverted(long gpio, boolean[] inverted);

/**

* Set the direction of the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param direction One of the direction values.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_set_direction")

public static native int gpioSetDirection(long gpio, int direction);

/**

* Set the interrupt edge of the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param edge One of the edge values.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_set_edge")

public static native int gpioSetEdge(long gpio, int edge);

/**

* Set the bias of the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param bias One of the bias values.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_set_bias")

public static native int gpioSetBias(long gpio, int bias);

/**

* Set the drive of the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param drive One of the drive values.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_set_drive")

public static native int gpioSetDrive(long gpio, int drive);

/**

* Set the inverted value of the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param inverted Is line inverted (active low)?

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_set_inverted")

public static native int gpioSetInverted(long gpio, boolean inverted);

/**

* Return the line the GPIO handle was opened with.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @return Line the GPIO handle was opened with.

*/

@JniMethod(accessor = "gpio_line")

public static native int gpioLine(long gpio);

/**

* Return the line file descriptor of the GPIO handle.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @return Line file descriptor.

*/

@JniMethod(accessor = "gpio_fd")

public static native int gpioFd(long gpio);

/**

* Return the line name of the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param str Line name.

* @param len Length of char array.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_name")

public static native int gpioName(long gpio, byte[] str, long len);

/**

* Return the line name of the GPIO. Wraps native method and simplifies.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @return Line name.

*/

public static String gpioName(long gpio) {

var str = new byte[MAX_CHAR_ARRAY_LEN];

if (gpioName(gpio, str, str.length) < 0) {

throw new RuntimeException(gpioErrMessage(gpio));

}

return jString(str);

}

/**

* Return the line label of the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param str Line label.

* @param len Length of char array.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_label")

public static native int gpioLabel(long gpio, byte[] str, long len);

/**

* Return the line lable of the GPIO. Wraps native method and simplifies.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @return Line label.

*/

public static String gpioLabel(long gpio) {

var str = new byte[MAX_CHAR_ARRAY_LEN];

if (gpioLabel(gpio, str, str.length) < 0) {

throw new RuntimeException(gpioErrMessage(gpio));

}

return jString(str);

}

/**

* Return the GPIO chip file descriptor of the GPIO handle.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @return GPIO chip file descriptor.

*/

@JniMethod(accessor = "gpio_chip_fd")

public static native int gpioChipFd(long gpio);

/**

* Return the name of the GPIO chip associated with the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param str Name of the GPIO chip.

* @param len Length of char array.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_chip_name")

public static native int gpioChipName(long gpio, byte[] str, long len);

/**

* Return the name of the GPIO chip associated with the GPIO. Wraps native method and simplifies.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @return

*/

public static String gpioChipName(long gpio) {

var str = new byte[MAX_CHAR_ARRAY_LEN];

if (gpioChipName(gpio, str, str.length) < 0) {

throw new RuntimeException(gpioErrMessage(gpio));

}

return jString(str);

}

/**

* Return the label of the GPIO chip associated with the GPIO.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param str Label of the GPIO chip.

* @param len Length of char array.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_chip_label")

public static native int gpioChipLabel(long gpio, byte[] str, long len);

/**

* Return the label of the GPIO chip associated with the GPIO. Wraps native method and simplifies.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @return GPIO label.

*/

public static String gpioChipLabel(long gpio) {

var str = new byte[MAX_CHAR_ARRAY_LEN];

if (gpioChipLabel(gpio, str, str.length) < 0) {

throw new RuntimeException(gpioErrMessage(gpio));

}

return jString(str);

}

/**

*

* Return a string representation of the GPIO handle.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @param str String representation of the GPIO handle.

* @param len Length of char array.

* @return 0 on success, or a negative GPIO error code on failure.

*/

@JniMethod(accessor = "gpio_tostring")

public static native int gpioToString(long gpio, byte[] str, long len);

/**

* Return a string representation of the GPIO handle. Wraps native method and simplifies.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @return GPIO handle as String.

*/

public static String gpioToString(long gpio) {

var str = new byte[MAX_CHAR_ARRAY_LEN];

if (gpioToString(gpio, str, str.length) < 0) {

throw new RuntimeException(gpioErrMessage(gpio));

}

return jString(str);

}

/**

* Return the libc errno of the last failure that occurred.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @return libc errno.

*/

@JniMethod(accessor = "gpio_errno")

public static native int gpioErrNo(long gpio);

/**

* Return a human readable error message pointer of the last failure that occurred.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @return Error message pointer.

*/

@JniMethod(accessor = "gpio_errmsg")

public static native long gpioErrMsg(long gpio);

/**

* Return a human readable error message of the last failure that occurred. Converts const char * returned by gpio_errmsg to a

* Java String.

*

* @param gpio Valid pointer to an allocated GPIO handle structure.

* @return Error message.

*/

public static String gpioErrMessage(long gpio) {

var ptr = gpioErrMsg(gpio);

var str = new byte[MAX_CHAR_ARRAY_LEN];

memMove(str, ptr, str.length);

return jString(str);

}

}