@@ -5,5 +5,6 @@
[workspace]
members = [
+ "libgpiod",
"libgpiod-sys"
]
new file mode 100644
@@ -0,0 +1,22 @@
+# SPDX-License-Identifier: CC0-1.0
+# SPDX-FileCopyrightText: 2022 Linaro Ltd.
+# SPDX-FileCopyrightTest: 2022 Viresh Kumar <viresh.kumar@linaro.org>
+
+[package]
+name = "libgpiod"
+version = "0.1.0"
+authors = ["Viresh Kumar <viresh.kumar@linaro.org>"]
+description = "libgpiod wrappers"
+repository = "https://git.kernel.org/pub/scm/libs/libgpiod/libgpiod.git"
+categories = ["api-bindings", "hardware-support", "embedded", "os::linux-apis"]
+rust-version = "1.56"
+keywords = ["libgpiod", "gpio"]
+license = "Apache-2.0 OR BSD-3-Clause"
+edition = "2021"
+
+[dependencies]
+errno = "0.2.8"
+intmap = "2.0.0"
+libc = "0.2.39"
+libgpiod-sys = { path = "../libgpiod-sys" }
+thiserror = "1.0"
new file mode 100644
@@ -0,0 +1,309 @@
+// SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause
+// SPDX-FileCopyrightText: 2022 Linaro Ltd.
+// SPDX-FileCopyrightTest: 2022 Viresh Kumar <viresh.kumar@linaro.org>
+
+pub mod info {
+ /// GPIO chip info event related definitions.
+ pub use crate::info_event::*;
+}
+
+use std::cmp::Ordering;
+use std::ffi::{CStr, CString};
+use std::os::{raw::c_char, unix::prelude::AsRawFd};
+use std::path::Path;
+use std::str;
+use std::sync::Arc;
+use std::time::Duration;
+
+use super::{
+ gpiod,
+ line::{self, Offset},
+ request, Error, OperationType, Result,
+};
+
+#[derive(Debug, Eq, PartialEq)]
+struct Internal {
+ chip: *mut gpiod::gpiod_chip,
+}
+
+impl Internal {
+ /// Find a chip by path.
+ fn open<P: AsRef<Path>>(path: &P) -> Result<Self> {
+ // Null-terminate the string
+ let path = path.as_ref().to_string_lossy() + "\0";
+
+ // SAFETY: The `gpiod_chip` returned by libgpiod is guaranteed to live as long
+ // as the `struct Internal`.
+ let chip = unsafe { gpiod::gpiod_chip_open(path.as_ptr() as *const c_char) };
+ if chip.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::ChipOpen,
+ errno::errno(),
+ ));
+ }
+
+ Ok(Self { chip })
+ }
+}
+
+impl Drop for Internal {
+ /// Close the chip and release all associated resources.
+ fn drop(&mut self) {
+ // SAFETY: `gpiod_chip` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_chip_close(self.chip) }
+ }
+}
+
+/// GPIO chip
+///
+/// A GPIO chip object is associated with an open file descriptor to the GPIO
+/// character device. It exposes basic information about the chip and allows
+/// callers to retrieve information about each line, watch lines for state
+/// changes and make line requests.
+#[derive(Debug, Eq, PartialEq)]
+pub struct Chip {
+ ichip: Arc<Internal>,
+}
+
+// SAFETY: Safe as `Internal` won't be freed until the `Chip` is dropped.
+unsafe impl Send for Chip {}
+
+impl Chip {
+ /// Find a chip by path.
+ pub fn open<P: AsRef<Path>>(path: &P) -> Result<Self> {
+ let ichip = Arc::new(Internal::open(path)?);
+
+ Ok(Self { ichip })
+ }
+
+ /// Get the chip name as represented in the kernel.
+ pub fn info(&self) -> Result<Info> {
+ Info::new(self.ichip.clone())
+ }
+
+ /// Get the path used to find the chip.
+ pub fn path(&self) -> Result<&str> {
+ // SAFETY: The string returned by libgpiod is guaranteed to live as long
+ // as the `struct Chip`.
+ let path = unsafe { gpiod::gpiod_chip_get_path(self.ichip.chip) };
+
+ // SAFETY: The string is guaranteed to be valid here by the C API.
+ unsafe { CStr::from_ptr(path) }
+ .to_str()
+ .map_err(Error::StringNotUtf8)
+ }
+
+ /// Get a snapshot of information about the line.
+ pub fn line_info(&self, offset: Offset) -> Result<line::Info> {
+ // SAFETY: The `gpiod_line_info` returned by libgpiod is guaranteed to live as long
+ // as the `struct Info`.
+ let info = unsafe { gpiod::gpiod_chip_get_line_info(self.ichip.chip, offset) };
+
+ if info.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::ChipGetLineInfo,
+ errno::errno(),
+ ));
+ }
+
+ line::Info::new(info)
+ }
+
+ /// Get the current snapshot of information about the line at given offset and start watching
+ /// it for future changes.
+ pub fn watch_line_info(&self, offset: Offset) -> Result<line::Info> {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ let info = unsafe { gpiod::gpiod_chip_watch_line_info(self.ichip.chip, offset) };
+
+ if info.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::ChipWatchLineInfo,
+ errno::errno(),
+ ));
+ }
+
+ line::Info::new_watch(info)
+ }
+
+ /// Stop watching a line
+ pub fn unwatch(&self, offset: Offset) {
+ // SAFETY: `gpiod_chip` is guaranteed to be valid here.
+ unsafe {
+ gpiod::gpiod_chip_unwatch_line_info(self.ichip.chip, offset);
+ }
+ }
+
+ /// Wait for line status events on any of the watched lines on the chip.
+ pub fn wait_info_event(&self, timeout: Option<Duration>) -> Result<bool> {
+ let timeout = match timeout {
+ Some(x) => x.as_nanos() as i64,
+ // Block indefinitely
+ None => -1,
+ };
+
+ // SAFETY: `gpiod_chip` is guaranteed to be valid here.
+ let ret = unsafe { gpiod::gpiod_chip_wait_info_event(self.ichip.chip, timeout) };
+
+ match ret {
+ -1 => Err(Error::OperationFailed(
+ OperationType::ChipWaitInfoEvent,
+ errno::errno(),
+ )),
+ 0 => Ok(false),
+ _ => Ok(true),
+ }
+ }
+
+ /// Read a single line status change event from the chip. If no events are
+ /// pending, this function will block.
+ pub fn read_info_event(&self) -> Result<info::Event> {
+ // SAFETY: The `gpiod_info_event` returned by libgpiod is guaranteed to live as long
+ // as the `struct Event`.
+ let event = unsafe { gpiod::gpiod_chip_read_info_event(self.ichip.chip) };
+ if event.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::ChipReadInfoEvent,
+ errno::errno(),
+ ));
+ }
+
+ Ok(info::Event::new(event))
+ }
+
+ /// Map a GPIO line's name to its offset within the chip.
+ pub fn line_offset_from_name(&self, name: &str) -> Result<Offset> {
+ let name = CString::new(name).map_err(|_| Error::InvalidString)?;
+
+ // SAFETY: `gpiod_chip` is guaranteed to be valid here.
+ let ret = unsafe {
+ gpiod::gpiod_chip_get_line_offset_from_name(
+ self.ichip.chip,
+ name.as_ptr() as *const c_char,
+ )
+ };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::ChipGetLineOffsetFromName,
+ errno::errno(),
+ ))
+ } else {
+ Ok(ret as u32)
+ }
+ }
+
+ /// Request a set of lines for exclusive usage.
+ pub fn request_lines(
+ &self,
+ rconfig: &request::Config,
+ lconfig: &line::Config,
+ ) -> Result<request::Request> {
+ // SAFETY: The `gpiod_line_request` returned by libgpiod is guaranteed to live as long
+ // as the `struct Request`.
+ let request = unsafe {
+ gpiod::gpiod_chip_request_lines(self.ichip.chip, rconfig.config, lconfig.config)
+ };
+
+ if request.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::ChipRequestLines,
+ errno::errno(),
+ ));
+ }
+
+ request::Request::new(request)
+ }
+}
+
+impl AsRawFd for Chip {
+ /// Get the file descriptor associated with the chip.
+ ///
+ /// The returned file descriptor must not be closed by the caller, else other methods for the
+ /// `struct Chip` may fail.
+ fn as_raw_fd(&self) -> i32 {
+ // SAFETY: `gpiod_chip` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_chip_get_fd(self.ichip.chip) }
+ }
+}
+
+/// GPIO chip Information
+#[derive(Debug, Eq)]
+pub struct Info {
+ info: *mut gpiod::gpiod_chip_info,
+}
+
+impl Info {
+ /// Find a GPIO chip by path.
+ fn new(chip: Arc<Internal>) -> Result<Self> {
+ // SAFETY: `gpiod_chip` is guaranteed to be valid here.
+ let info = unsafe { gpiod::gpiod_chip_get_info(chip.chip) };
+ if info.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::ChipGetInfo,
+ errno::errno(),
+ ));
+ }
+
+ Ok(Self { info })
+ }
+
+ /// Get the GPIO chip name as represented in the kernel.
+ pub fn name(&self) -> Result<&str> {
+ // SAFETY: The string returned by libgpiod is guaranteed to live as long
+ // as the `struct Chip`.
+ let name = unsafe { gpiod::gpiod_chip_info_get_name(self.info) };
+
+ // SAFETY: The string is guaranteed to be valid here by the C API.
+ unsafe { CStr::from_ptr(name) }
+ .to_str()
+ .map_err(Error::StringNotUtf8)
+ }
+
+ /// Get the GPIO chip label as represented in the kernel.
+ pub fn label(&self) -> Result<&str> {
+ // SAFETY: The string returned by libgpiod is guaranteed to live as long
+ // as the `struct Chip`.
+ let label = unsafe { gpiod::gpiod_chip_info_get_label(self.info) };
+
+ // SAFETY: The string is guaranteed to be valid here by the C API.
+ unsafe { CStr::from_ptr(label) }
+ .to_str()
+ .map_err(Error::StringNotUtf8)
+ }
+
+ /// Get the number of GPIO lines exposed by the chip.
+ pub fn num_lines(&self) -> usize {
+ // SAFETY: `gpiod_chip` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_chip_info_get_num_lines(self.info) as usize }
+ }
+}
+
+impl PartialEq for Info {
+ fn eq(&self, other: &Self) -> bool {
+ self.name().unwrap().eq(other.name().unwrap())
+ }
+}
+
+impl PartialOrd for Info {
+ fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+ let name = match self.name() {
+ Ok(name) => name,
+ _ => return None,
+ };
+
+ let other_name = match other.name() {
+ Ok(name) => name,
+ _ => return None,
+ };
+
+ name.partial_cmp(other_name)
+ }
+}
+
+impl Drop for Info {
+ /// Close the GPIO chip info and release all associated resources.
+ fn drop(&mut self) {
+ // SAFETY: `gpiod_chip` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_chip_info_free(self.info) }
+ }
+}
new file mode 100644
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause
+// SPDX-FileCopyrightText: 2022 Linaro Ltd.
+// SPDX-FileCopyrightTest: 2022 Viresh Kumar <viresh.kumar@linaro.org>
+
+use std::time::Duration;
+
+use super::{
+ gpiod,
+ line::{EdgeKind, Offset},
+ Error, OperationType, Result,
+};
+
+/// Line edge events handling
+///
+/// An edge event object contains information about a single line edge event.
+/// It contains the event type, timestamp and the offset of the line on which
+/// the event occurred as well as two sequence numbers (global for all lines
+/// in the associated request and local for this line only).
+///
+/// Edge events are stored into an edge-event buffer object to improve
+/// performance and to limit the number of memory allocations when a large
+/// number of events are being read.
+
+#[derive(Debug, Eq, PartialEq)]
+pub struct Event(*mut gpiod::gpiod_edge_event);
+
+impl Event {
+ pub fn event_clone(event: &Event) -> Result<Event> {
+ // SAFETY: `gpiod_edge_event` is guaranteed to be valid here.
+ let event = unsafe { gpiod::gpiod_edge_event_copy(event.0) };
+ if event.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::EdgeEventCopy,
+ errno::errno(),
+ ));
+ }
+
+ Ok(Self(event))
+ }
+
+ /// Get the event type.
+ pub fn event_type(&self) -> Result<EdgeKind> {
+ // SAFETY: `gpiod_edge_event` is guaranteed to be valid here.
+ EdgeKind::new(unsafe { gpiod::gpiod_edge_event_get_event_type(self.0) } as u32)
+ }
+
+ /// Get the timestamp of the event.
+ pub fn timestamp(&self) -> Duration {
+ // SAFETY: `gpiod_edge_event` is guaranteed to be valid here.
+ Duration::from_nanos(unsafe { gpiod::gpiod_edge_event_get_timestamp_ns(self.0) })
+ }
+
+ /// Get the offset of the line on which the event was triggered.
+ pub fn line_offset(&self) -> Offset {
+ // SAFETY: `gpiod_edge_event` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_edge_event_get_line_offset(self.0) }
+ }
+
+ /// Get the global sequence number of the event.
+ ///
+ /// Returns sequence number of the event relative to all lines in the
+ /// associated line request.
+ pub fn global_seqno(&self) -> usize {
+ // SAFETY: `gpiod_edge_event` is guaranteed to be valid here.
+ unsafe {
+ gpiod::gpiod_edge_event_get_global_seqno(self.0)
+ .try_into()
+ .unwrap()
+ }
+ }
+
+ /// Get the event sequence number specific to concerned line.
+ ///
+ /// Returns sequence number of the event relative to the line within the
+ /// lifetime of the associated line request.
+ pub fn line_seqno(&self) -> usize {
+ // SAFETY: `gpiod_edge_event` is guaranteed to be valid here.
+ unsafe {
+ gpiod::gpiod_edge_event_get_line_seqno(self.0)
+ .try_into()
+ .unwrap()
+ }
+ }
+}
+
+impl Drop for Event {
+ /// Free the edge event.
+ fn drop(&mut self) {
+ // SAFETY: `gpiod_edge_event` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_edge_event_free(self.0) };
+ }
+}
new file mode 100644
@@ -0,0 +1,168 @@
+// SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause
+// SPDX-FileCopyrightText: 2022 Linaro Ltd.
+// SPDX-FileCopyrightTest: 2022 Viresh Kumar <viresh.kumar@linaro.org>
+
+use std::os::raw::c_ulong;
+use std::ptr;
+
+use super::{
+ gpiod,
+ request::{Event, Request},
+ Error, OperationType, Result,
+};
+
+/// Line edge events
+///
+/// An iterator over the elements of type `Event`.
+
+pub struct Events<'a> {
+ buffer: &'a mut Buffer,
+ read_index: usize,
+ len: usize,
+}
+
+impl<'a> Events<'a> {
+ pub fn new(buffer: &'a mut Buffer, len: usize) -> Self {
+ Self {
+ buffer,
+ read_index: 0,
+ len,
+ }
+ }
+
+ /// Get the number of contained events in the snapshot, this doesn't change
+ /// on reading events from the iterator.
+ pub fn len(&self) -> usize {
+ self.len
+ }
+
+ /// Check if buffer is empty.
+ pub fn is_empty(&self) -> bool {
+ self.len == 0
+ }
+}
+
+impl<'a> Iterator for Events<'a> {
+ type Item = Result<&'a Event>;
+
+ fn nth(&mut self, n: usize) -> Option<Self::Item> {
+ if self.read_index + n >= self.len {
+ return None;
+ }
+
+ self.read_index += n + 1;
+ Some(self.buffer.event(self.read_index - 1))
+ }
+
+ fn next(&mut self) -> Option<Self::Item> {
+ self.nth(0)
+ }
+}
+
+/// Line edge events buffer
+#[derive(Debug, Eq, PartialEq)]
+pub struct Buffer {
+ pub(crate) buffer: *mut gpiod::gpiod_edge_event_buffer,
+ events: Vec<*mut gpiod::gpiod_edge_event>,
+}
+
+impl Buffer {
+ /// Create a new edge event buffer.
+ ///
+ /// If capacity equals 0, it will be set to a default value of 64. If
+ /// capacity is larger than 1024, it will be limited to 1024.
+ pub fn new(capacity: usize) -> Result<Self> {
+ // SAFETY: The `gpiod_edge_event_buffer` returned by libgpiod is guaranteed to live as long
+ // as the `struct Buffer`.
+ let buffer = unsafe { gpiod::gpiod_edge_event_buffer_new(capacity as c_ulong) };
+ if buffer.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::EdgeEventBufferNew,
+ errno::errno(),
+ ));
+ }
+
+ // SAFETY: `gpiod_edge_event_buffer` is guaranteed to be valid here.
+ let capacity = unsafe { gpiod::gpiod_edge_event_buffer_get_capacity(buffer) as usize };
+
+ Ok(Self {
+ buffer,
+ events: vec![ptr::null_mut(); capacity],
+ })
+ }
+
+ /// Get the capacity of the event buffer.
+ pub fn capacity(&self) -> usize {
+ self.events.len()
+ }
+
+ /// Get edge events from a line request.
+ ///
+ /// This function will block if no event was queued for the line.
+ pub fn read_edge_events(&mut self, request: &Request) -> Result<Events> {
+ for i in 0..self.events.len() {
+ self.events[i] = ptr::null_mut();
+ }
+
+ // SAFETY: `gpiod_line_request` is guaranteed to be valid here.
+ let ret = unsafe {
+ gpiod::gpiod_line_request_read_edge_event(
+ request.request,
+ self.buffer,
+ self.events.len().try_into().unwrap(),
+ )
+ };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineRequestReadEdgeEvent,
+ errno::errno(),
+ ))
+ } else {
+ let ret = ret as usize;
+
+ if ret > self.events.len() {
+ Err(Error::TooManyEvents(ret, self.events.len()))
+ } else {
+ Ok(Events::new(self, ret))
+ }
+ }
+ }
+
+ /// Read an event stored in the buffer.
+ fn event<'a>(&mut self, index: usize) -> Result<&'a Event> {
+ if self.events[index].is_null() {
+ // SAFETY: The `gpiod_edge_event` returned by libgpiod is guaranteed to live as long
+ // as the `struct Event`.
+ let event = unsafe {
+ gpiod::gpiod_edge_event_buffer_get_event(self.buffer, index.try_into().unwrap())
+ };
+
+ if event.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::EdgeEventBufferGetEvent,
+ errno::errno(),
+ ));
+ }
+
+ self.events[index] = event;
+ }
+
+ // SAFETY: Safe as the underlying events object won't get freed until the time the returned
+ // reference is still used.
+ Ok(unsafe {
+ // This will not lead to `drop(event)`.
+ (self.events.as_ptr().add(index) as *const Event)
+ .as_ref()
+ .unwrap()
+ })
+ }
+}
+
+impl Drop for Buffer {
+ /// Free the edge event buffer and release all associated resources.
+ fn drop(&mut self) {
+ // SAFETY: `gpiod_edge_event_buffer` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_edge_event_buffer_free(self.buffer) };
+ }
+}
new file mode 100644
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause
+// SPDX-FileCopyrightText: 2022 Linaro Ltd.
+// SPDX-FileCopyrightTest: 2022 Viresh Kumar <viresh.kumar@linaro.org>
+
+use std::time::Duration;
+
+use super::{
+ gpiod,
+ line::{self, InfoChangeKind},
+ Error, OperationType, Result,
+};
+
+/// Line status watch events
+///
+/// Accessors for the info event objects allowing to monitor changes in GPIO
+/// line state.
+///
+/// Callers can be notified about changes in line's state using the interfaces
+/// exposed by GPIO chips. Each info event contains information about the event
+/// itself (timestamp, type) as well as a snapshot of line's state in the form
+/// of a line-info object.
+
+#[derive(Debug, Eq, PartialEq)]
+pub struct Event {
+ pub(crate) event: *mut gpiod::gpiod_info_event,
+}
+
+impl Event {
+ /// Get a single chip's line's status change event.
+ pub(crate) fn new(event: *mut gpiod::gpiod_info_event) -> Self {
+ Self { event }
+ }
+
+ /// Get the event type of the status change event.
+ pub fn event_type(&self) -> Result<InfoChangeKind> {
+ // SAFETY: `gpiod_info_event` is guaranteed to be valid here.
+ InfoChangeKind::new(unsafe { gpiod::gpiod_info_event_get_event_type(self.event) } as u32)
+ }
+
+ /// Get the timestamp of the event, read from the monotonic clock.
+ pub fn timestamp(&self) -> Duration {
+ // SAFETY: `gpiod_info_event` is guaranteed to be valid here.
+ Duration::from_nanos(unsafe { gpiod::gpiod_info_event_get_timestamp_ns(self.event) })
+ }
+
+ /// Get the line-info object associated with the event.
+ pub fn line_info(&self) -> Result<line::Info> {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ let info = unsafe { gpiod::gpiod_info_event_get_line_info(self.event) };
+
+ if info.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::InfoEventGetLineInfo,
+ errno::errno(),
+ ));
+ }
+
+ line::Info::new_from_event(info)
+ }
+}
+
+impl Drop for Event {
+ /// Free the info event object and release all associated resources.
+ fn drop(&mut self) {
+ // SAFETY: `gpiod_info_event` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_info_event_free(self.event) }
+ }
+}
new file mode 100644
@@ -0,0 +1,478 @@
+// SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause
+// SPDX-FileCopyrightText: 2022 Linaro Ltd.
+// SPDX-FileCopyrightTest: 2022 Viresh Kumar <viresh.kumar@linaro.org>
+//
+// Rust wrappers for GPIOD APIs
+
+//! libgpiod public API
+//!
+//! This is the complete documentation of the public Rust API made available to
+//! users of libgpiod.
+//!
+//! The API is logically split into several parts such as: GPIO chip & line
+//! operators, GPIO events handling etc.
+
+use std::ffi::CStr;
+use std::fs;
+use std::os::raw::c_char;
+use std::path::Path;
+use std::time::Duration;
+use std::{fmt, str};
+
+use intmap::IntMap;
+use thiserror::Error as ThisError;
+
+use libgpiod_sys as gpiod;
+
+/// Operation types, used with OperationFailed() Error.
+#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+pub enum OperationType {
+ ChipOpen,
+ ChipWaitInfoEvent,
+ ChipGetLine,
+ ChipGetLineInfo,
+ ChipGetLineOffsetFromName,
+ ChipGetInfo,
+ ChipReadInfoEvent,
+ ChipRequestLines,
+ ChipWatchLineInfo,
+ EdgeEventBufferGetEvent,
+ EdgeEventCopy,
+ EdgeEventBufferNew,
+ InfoEventGetLineInfo,
+ LineConfigNew,
+ LineConfigAddSettings,
+ LineConfigGetOffsets,
+ LineConfigGetSettings,
+ LineRequestReconfigLines,
+ LineRequestGetVal,
+ LineRequestGetValSubset,
+ LineRequestSetVal,
+ LineRequestSetValSubset,
+ LineRequestReadEdgeEvent,
+ LineRequestWaitEdgeEvent,
+ LineSettingsNew,
+ LineSettingsCopy,
+ LineSettingsGetOutVal,
+ LineSettingsSetDirection,
+ LineSettingsSetEdgeDetection,
+ LineSettingsSetBias,
+ LineSettingsSetDrive,
+ LineSettingsSetActiveLow,
+ LineSettingsSetDebouncePeriod,
+ LineSettingsSetEventClock,
+ LineSettingsSetOutputValue,
+ RequestConfigNew,
+ RequestConfigGetConsumer,
+ SimBankGetVal,
+ SimBankNew,
+ SimBankSetLabel,
+ SimBankSetNumLines,
+ SimBankSetLineName,
+ SimBankSetPull,
+ SimBankHogLine,
+ SimCtxNew,
+ SimDevNew,
+ SimDevEnable,
+ SimDevDisable,
+}
+
+impl fmt::Display for OperationType {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ write!(f, "{:?}", self)
+ }
+}
+
+/// Result of libgpiod operations.
+pub type Result<T> = std::result::Result<T, Error>;
+
+/// Error codes for libgpiod operations.
+#[derive(Copy, Clone, Debug, Eq, PartialEq, ThisError)]
+pub enum Error {
+ #[error("Failed to get {0}")]
+ NullString(&'static str),
+ #[error("String not utf8: {0:?}")]
+ StringNotUtf8(str::Utf8Error),
+ #[error("Invalid String")]
+ InvalidString,
+ #[error("Invalid enum {0} value: {1}")]
+ InvalidEnumValue(&'static str, u32),
+ #[error("Operation {0} Failed: {1}")]
+ OperationFailed(OperationType, errno::Errno),
+ #[error("Invalid Arguments")]
+ InvalidArguments,
+ #[error("Event count more than buffer capacity: {0} > {1}")]
+ TooManyEvents(usize, usize),
+ #[error("Std Io Error")]
+ IoError,
+}
+
+mod info_event;
+
+/// GPIO chip related definitions.
+pub mod chip;
+
+mod edge_event;
+mod event_buffer;
+mod line_request;
+mod request_config;
+
+/// GPIO chip request related definitions.
+pub mod request {
+ pub use crate::edge_event::*;
+ pub use crate::event_buffer::*;
+ pub use crate::line_request::*;
+ pub use crate::request_config::*;
+}
+
+mod line_config;
+mod line_info;
+mod line_settings;
+
+/// GPIO chip line related definitions.
+pub mod line {
+ pub use crate::line_config::*;
+ pub use crate::line_info::*;
+ pub use crate::line_settings::*;
+
+ use super::*;
+
+ /// Value settings.
+ #[derive(Copy, Clone, Debug, Eq, PartialEq)]
+ pub enum Value {
+ /// Active
+ Active,
+ /// Inactive
+ InActive,
+ }
+
+ /// Maps offset to Value.
+ pub type ValueMap = IntMap<Value>;
+
+ impl Value {
+ pub fn new(val: i32) -> Result<Self> {
+ Ok(match val {
+ 0 => Value::InActive,
+ 1 => Value::Active,
+ _ => return Err(Error::InvalidEnumValue("Value", val as u32)),
+ })
+ }
+
+ pub(crate) fn value(&self) -> i32 {
+ match self {
+ Value::Active => 1,
+ Value::InActive => 0,
+ }
+ }
+ }
+
+ /// Offset type.
+ pub type Offset = u32;
+
+ /// Direction settings.
+ #[derive(Copy, Clone, Debug, Eq, PartialEq)]
+ pub enum Direction {
+ /// Request the line(s), but don't change direction.
+ AsIs,
+ /// Direction is input - for reading the value of an externally driven GPIO line.
+ Input,
+ /// Direction is output - for driving the GPIO line.
+ Output,
+ }
+
+ impl Direction {
+ pub(crate) fn new(dir: u32) -> Result<Self> {
+ Ok(match dir {
+ gpiod::GPIOD_LINE_DIRECTION_AS_IS => Direction::AsIs,
+ gpiod::GPIOD_LINE_DIRECTION_INPUT => Direction::Input,
+ gpiod::GPIOD_LINE_DIRECTION_OUTPUT => Direction::Output,
+ _ => return Err(Error::InvalidEnumValue("Direction", dir)),
+ })
+ }
+
+ pub(crate) fn gpiod_direction(&self) -> u32 {
+ match self {
+ Direction::AsIs => gpiod::GPIOD_LINE_DIRECTION_AS_IS,
+ Direction::Input => gpiod::GPIOD_LINE_DIRECTION_INPUT,
+ Direction::Output => gpiod::GPIOD_LINE_DIRECTION_OUTPUT,
+ }
+ }
+ }
+
+ /// Internal bias settings.
+ #[derive(Copy, Clone, Debug, Eq, PartialEq)]
+ pub enum Bias {
+ /// The internal bias is disabled.
+ Disabled,
+ /// The internal pull-up bias is enabled.
+ PullUp,
+ /// The internal pull-down bias is enabled.
+ PullDown,
+ }
+
+ impl Bias {
+ pub(crate) fn new(bias: u32) -> Result<Option<Self>> {
+ Ok(match bias {
+ gpiod::GPIOD_LINE_BIAS_UNKNOWN => None,
+ gpiod::GPIOD_LINE_BIAS_AS_IS => None,
+ gpiod::GPIOD_LINE_BIAS_DISABLED => Some(Bias::Disabled),
+ gpiod::GPIOD_LINE_BIAS_PULL_UP => Some(Bias::PullUp),
+ gpiod::GPIOD_LINE_BIAS_PULL_DOWN => Some(Bias::PullDown),
+ _ => return Err(Error::InvalidEnumValue("Bias", bias)),
+ })
+ }
+
+ pub(crate) fn gpiod_bias(bias: Option<Bias>) -> u32 {
+ match bias {
+ None => gpiod::GPIOD_LINE_BIAS_AS_IS,
+ Some(bias) => match bias {
+ Bias::Disabled => gpiod::GPIOD_LINE_BIAS_DISABLED,
+ Bias::PullUp => gpiod::GPIOD_LINE_BIAS_PULL_UP,
+ Bias::PullDown => gpiod::GPIOD_LINE_BIAS_PULL_DOWN,
+ },
+ }
+ }
+ }
+
+ /// Drive settings.
+ #[derive(Copy, Clone, Debug, Eq, PartialEq)]
+ pub enum Drive {
+ /// Drive setting is push-pull.
+ PushPull,
+ /// Line output is open-drain.
+ OpenDrain,
+ /// Line output is open-source.
+ OpenSource,
+ }
+
+ impl Drive {
+ pub(crate) fn new(drive: u32) -> Result<Self> {
+ Ok(match drive {
+ gpiod::GPIOD_LINE_DRIVE_PUSH_PULL => Drive::PushPull,
+ gpiod::GPIOD_LINE_DRIVE_OPEN_DRAIN => Drive::OpenDrain,
+ gpiod::GPIOD_LINE_DRIVE_OPEN_SOURCE => Drive::OpenSource,
+ _ => return Err(Error::InvalidEnumValue("Drive", drive)),
+ })
+ }
+
+ pub(crate) fn gpiod_drive(&self) -> u32 {
+ match self {
+ Drive::PushPull => gpiod::GPIOD_LINE_DRIVE_PUSH_PULL,
+ Drive::OpenDrain => gpiod::GPIOD_LINE_DRIVE_OPEN_DRAIN,
+ Drive::OpenSource => gpiod::GPIOD_LINE_DRIVE_OPEN_SOURCE,
+ }
+ }
+ }
+
+ /// Edge detection settings.
+ #[derive(Copy, Clone, Debug, Eq, PartialEq)]
+ pub enum Edge {
+ /// Line detects rising edge events.
+ Rising,
+ /// Line detects falling edge events.
+ Falling,
+ /// Line detects both rising and falling edge events.
+ Both,
+ }
+
+ impl Edge {
+ pub(crate) fn new(edge: u32) -> Result<Option<Self>> {
+ Ok(match edge {
+ gpiod::GPIOD_LINE_EDGE_NONE => None,
+ gpiod::GPIOD_LINE_EDGE_RISING => Some(Edge::Rising),
+ gpiod::GPIOD_LINE_EDGE_FALLING => Some(Edge::Falling),
+ gpiod::GPIOD_LINE_EDGE_BOTH => Some(Edge::Both),
+ _ => return Err(Error::InvalidEnumValue("Edge", edge)),
+ })
+ }
+
+ pub(crate) fn gpiod_edge(edge: Option<Edge>) -> u32 {
+ match edge {
+ None => gpiod::GPIOD_LINE_EDGE_NONE,
+ Some(edge) => match edge {
+ Edge::Rising => gpiod::GPIOD_LINE_EDGE_RISING,
+ Edge::Falling => gpiod::GPIOD_LINE_EDGE_FALLING,
+ Edge::Both => gpiod::GPIOD_LINE_EDGE_BOTH,
+ },
+ }
+ }
+ }
+
+ /// Line setting kind.
+ #[derive(Copy, Clone, Debug, Eq, PartialEq)]
+ pub enum SettingKind {
+ /// Line direction.
+ Direction,
+ /// Bias.
+ Bias,
+ /// Drive.
+ Drive,
+ /// Edge detection.
+ EdgeDetection,
+ /// Active-low setting.
+ ActiveLow,
+ /// Debounce period.
+ DebouncePeriod,
+ /// Event clock type.
+ EventClock,
+ /// Output value.
+ OutputValue,
+ }
+
+ /// Line settings.
+ #[derive(Copy, Clone, Debug, Eq, PartialEq)]
+ pub enum SettingVal {
+ /// Line direction.
+ Direction(Direction),
+ /// Bias.
+ Bias(Option<Bias>),
+ /// Drive.
+ Drive(Drive),
+ /// Edge detection.
+ EdgeDetection(Option<Edge>),
+ /// Active-low setting.
+ ActiveLow(bool),
+ /// Debounce period.
+ DebouncePeriod(Duration),
+ /// Event clock type.
+ EventClock(EventClock),
+ /// Output value.
+ OutputValue(Value),
+ }
+
+ impl fmt::Display for SettingVal {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ write!(f, "{:?}", self)
+ }
+ }
+
+ /// Event clock settings.
+ #[derive(Copy, Clone, Debug, Eq, PartialEq)]
+ pub enum EventClock {
+ /// Line uses the monotonic clock for edge event timestamps.
+ Monotonic,
+ /// Line uses the realtime clock for edge event timestamps.
+ Realtime,
+ /// Line uses the hardware timestamp engine clock for edge event timestamps.
+ HTE,
+ }
+
+ impl EventClock {
+ pub(crate) fn new(clock: u32) -> Result<Self> {
+ Ok(match clock {
+ gpiod::GPIOD_LINE_EVENT_CLOCK_MONOTONIC => EventClock::Monotonic,
+ gpiod::GPIOD_LINE_EVENT_CLOCK_REALTIME => EventClock::Realtime,
+ gpiod::GPIOD_LINE_EVENT_CLOCK_HTE => EventClock::HTE,
+ _ => return Err(Error::InvalidEnumValue("Eventclock", clock)),
+ })
+ }
+
+ pub(crate) fn gpiod_clock(&self) -> u32 {
+ match self {
+ EventClock::Monotonic => gpiod::GPIOD_LINE_EVENT_CLOCK_MONOTONIC,
+ EventClock::Realtime => gpiod::GPIOD_LINE_EVENT_CLOCK_REALTIME,
+ EventClock::HTE => gpiod::GPIOD_LINE_EVENT_CLOCK_HTE,
+ }
+ }
+ }
+
+ /// Line status change event types.
+ #[derive(Copy, Clone, Debug, Eq, PartialEq)]
+ pub enum InfoChangeKind {
+ /// Line has been requested.
+ LineRequested,
+ /// Previously requested line has been released.
+ LineReleased,
+ /// Line configuration has changed.
+ LineConfigChanged,
+ }
+
+ impl InfoChangeKind {
+ pub(crate) fn new(kind: u32) -> Result<Self> {
+ Ok(match kind {
+ gpiod::GPIOD_INFO_EVENT_LINE_REQUESTED => InfoChangeKind::LineRequested,
+ gpiod::GPIOD_INFO_EVENT_LINE_RELEASED => InfoChangeKind::LineReleased,
+ gpiod::GPIOD_INFO_EVENT_LINE_CONFIG_CHANGED => InfoChangeKind::LineConfigChanged,
+ _ => return Err(Error::InvalidEnumValue("InfoChangeKind", kind)),
+ })
+ }
+ }
+
+ /// Edge event types.
+ #[derive(Copy, Clone, Debug, Eq, PartialEq)]
+ pub enum EdgeKind {
+ /// Rising edge event.
+ Rising,
+ /// Falling edge event.
+ Falling,
+ }
+
+ impl EdgeKind {
+ pub(crate) fn new(kind: u32) -> Result<Self> {
+ Ok(match kind {
+ gpiod::GPIOD_EDGE_EVENT_RISING_EDGE => EdgeKind::Rising,
+ gpiod::GPIOD_EDGE_EVENT_FALLING_EDGE => EdgeKind::Falling,
+ _ => return Err(Error::InvalidEnumValue("EdgeEvent", kind)),
+ })
+ }
+ }
+}
+
+/// Various libgpiod-related functions.
+
+/// Check if the file pointed to by path is a GPIO chip character device.
+///
+/// Returns true if the file exists and is a GPIO chip character device or a
+/// symbolic link to it.
+pub fn is_gpiochip_device<P: AsRef<Path>>(path: &P) -> bool {
+ // Null-terminate the string
+ let path = path.as_ref().to_string_lossy() + "\0";
+
+ // SAFETY: libgpiod won't access the path reference once the call returns.
+ unsafe { gpiod::gpiod_is_gpiochip_device(path.as_ptr() as *const c_char) }
+}
+
+/// GPIO devices.
+///
+/// Returns a vector of unique available GPIO Chips.
+///
+/// The chips are sorted in ascending order of the chip names.
+pub fn gpiochip_devices<P: AsRef<Path>>(path: &P) -> Result<Vec<chip::Chip>> {
+ let mut devices = Vec::new();
+
+ for entry in fs::read_dir(path).map_err(|_| Error::IoError)?.flatten() {
+ let path = entry.path();
+
+ if is_gpiochip_device(&path) {
+ let chip = chip::Chip::open(&path)?;
+ let info = chip.info()?;
+
+ devices.push((chip, info));
+ }
+ }
+
+ devices.sort_by(|a, b| a.1.partial_cmp(&b.1).unwrap());
+ devices.dedup_by(|a, b| a.1.eq(&b.1));
+
+ Ok(devices.into_iter().map(|a| a.0).collect())
+}
+
+/// Get the API version of the libgpiod library as a human-readable string.
+pub fn libgpiod_version() -> Result<&'static str> {
+ // SAFETY: The string returned by libgpiod is guaranteed to live forever.
+ let version = unsafe { gpiod::gpiod_version_string() };
+
+ if version.is_null() {
+ return Err(Error::NullString("GPIO library version"));
+ }
+
+ // SAFETY: The string is guaranteed to be valid here by the C API.
+ unsafe { CStr::from_ptr(version) }
+ .to_str()
+ .map_err(Error::StringNotUtf8)
+}
+
+/// Get the API version of the libgpiod crate as a human-readable string.
+pub fn crate_version() -> &'static str {
+ env!("CARGO_PKG_VERSION")
+}
new file mode 100644
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause
+// SPDX-FileCopyrightText: 2022 Linaro Ltd.
+// SPDX-FileCopyrightTest: 2022 Viresh Kumar <viresh.kumar@linaro.org>
+
+use std::os::raw::{c_ulong, c_void};
+use std::slice;
+
+use super::{
+ gpiod,
+ line::{Offset, Settings},
+ Error, OperationType, Result,
+};
+
+/// Line configuration objects.
+///
+/// The line-config object contains the configuration for lines that can be
+/// used in two cases:
+/// - when making a line request
+/// - when reconfiguring a set of already requested lines.
+///
+/// A new line-config object is empty. Using it in a request will lead to an
+/// error. In order for a line-config to become useful, it needs to be assigned
+/// at least one offset-to-settings mapping by calling
+/// ::gpiod_line_config_add_line_settings.
+///
+/// When calling ::gpiod_chip_request_lines, the library will request all
+/// offsets that were assigned settings in the order that they were assigned.
+
+#[derive(Debug, Eq, PartialEq)]
+pub struct Config {
+ pub(crate) config: *mut gpiod::gpiod_line_config,
+}
+
+impl Config {
+ /// Create a new line config object.
+ pub fn new() -> Result<Self> {
+ // SAFETY: The `gpiod_line_config` returned by libgpiod is guaranteed to live as long
+ // as the `struct Config`.
+ let config = unsafe { gpiod::gpiod_line_config_new() };
+
+ if config.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::LineConfigNew,
+ errno::errno(),
+ ));
+ }
+
+ Ok(Self { config })
+ }
+
+ /// Resets the entire configuration stored in the object. This is useful if
+ /// the user wants to reuse the object without reallocating it.
+ pub fn reset(&mut self) {
+ // SAFETY: `gpiod_line_config` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_config_reset(self.config) }
+ }
+
+ /// Add line settings for a set of offsets.
+ pub fn add_line_settings(&self, offsets: &[Offset], settings: Settings) -> Result<()> {
+ // SAFETY: `gpiod_line_config` is guaranteed to be valid here.
+ let ret = unsafe {
+ gpiod::gpiod_line_config_add_line_settings(
+ self.config,
+ offsets.as_ptr(),
+ offsets.len() as c_ulong,
+ settings.settings,
+ )
+ };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineConfigAddSettings,
+ errno::errno(),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ /// Get line settings for offset.
+ pub fn line_settings(&self, offset: Offset) -> Result<Settings> {
+ // SAFETY: `gpiod_line_config` is guaranteed to be valid here.
+ let settings = unsafe { gpiod::gpiod_line_config_get_line_settings(self.config, offset) };
+
+ if settings.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::LineConfigGetSettings,
+ errno::errno(),
+ ));
+ }
+
+ Ok(Settings::new_with_settings(settings))
+ }
+
+ /// Get configured offsets.
+ pub fn offsets(&self) -> Result<Vec<Offset>> {
+ let mut num: u64 = 0;
+ let mut ptr: *mut Offset = std::ptr::null_mut();
+
+ // SAFETY: The `ptr` array returned by libgpiod is guaranteed to live as long
+ // as it is not explicitly freed with `free()`.
+ let ret = unsafe {
+ gpiod::gpiod_line_config_get_offsets(
+ self.config,
+ &mut num as *mut _ as *mut _,
+ &mut ptr,
+ )
+ };
+
+ if ret == -1 {
+ return Err(Error::OperationFailed(
+ OperationType::LineConfigGetOffsets,
+ errno::errno(),
+ ));
+ }
+
+ // SAFETY: The `ptr` array returned by libgpiod is guaranteed to live as long
+ // as it is not explicitly freed with `free()`.
+ let offsets = unsafe { slice::from_raw_parts(ptr as *const Offset, num as usize).to_vec() };
+
+ // SAFETY: The `ptr` array is guaranteed to be valid here.
+ unsafe { libc::free(ptr as *mut c_void) };
+
+ Ok(offsets)
+ }
+}
+
+impl Drop for Config {
+ /// Free the line config object and release all associated resources.
+ fn drop(&mut self) {
+ // SAFETY: `gpiod_line_config` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_config_free(self.config) }
+ }
+}
new file mode 100644
@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause
+// SPDX-FileCopyrightText: 2022 Linaro Ltd.
+// SPDX-FileCopyrightTest: 2022 Viresh Kumar <viresh.kumar@linaro.org>
+
+use std::ffi::CStr;
+use std::str;
+use std::time::Duration;
+
+use super::{
+ gpiod,
+ line::{Bias, Direction, Drive, Edge, EventClock, Offset},
+ Error, Result,
+};
+
+/// Line info
+///
+/// Exposes functions for retrieving kernel information about both requested and
+/// free lines. Line info object contains an immutable snapshot of a line's status.
+///
+/// The line info contains all the publicly available information about a
+/// line, which does not include the line value. The line must be requested
+/// to access the line value.
+
+#[derive(Debug, Eq, PartialEq)]
+pub struct Info {
+ info: *mut gpiod::gpiod_line_info,
+ contained: bool,
+}
+
+impl Info {
+ fn new_internal(info: *mut gpiod::gpiod_line_info, contained: bool) -> Result<Self> {
+ Ok(Self { info, contained })
+ }
+
+ /// Get a snapshot of information about the line.
+ pub(crate) fn new(info: *mut gpiod::gpiod_line_info) -> Result<Self> {
+ Info::new_internal(info, false)
+ }
+
+ /// Get a snapshot of information about the line and start watching it for changes.
+ pub(crate) fn new_watch(info: *mut gpiod::gpiod_line_info) -> Result<Self> {
+ Info::new_internal(info, false)
+ }
+
+ /// Get the Line info object associated with an event.
+ pub(crate) fn new_from_event(info: *mut gpiod::gpiod_line_info) -> Result<Self> {
+ Info::new_internal(info, true)
+ }
+
+ /// Get the offset of the line within the GPIO chip.
+ ///
+ /// The offset uniquely identifies the line on the chip. The combination of the chip and offset
+ /// uniquely identifies the line within the system.
+
+ pub fn offset(&self) -> Offset {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_info_get_offset(self.info) }
+ }
+
+ /// Get GPIO line's name.
+ pub fn name(&self) -> Result<&str> {
+ // SAFETY: The string returned by libgpiod is guaranteed to live as long
+ // as the `struct Info`.
+ let name = unsafe { gpiod::gpiod_line_info_get_name(self.info) };
+ if name.is_null() {
+ return Err(Error::NullString("GPIO line's name"));
+ }
+
+ // SAFETY: The string is guaranteed to be valid here by the C API.
+ unsafe { CStr::from_ptr(name) }
+ .to_str()
+ .map_err(Error::StringNotUtf8)
+ }
+
+ /// Returns True if the line is in use, false otherwise.
+ ///
+ /// The user space can't know exactly why a line is busy. It may have been
+ /// requested by another process or hogged by the kernel. It only matters that
+ /// the line is used and we can't request it.
+ pub fn is_used(&self) -> bool {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_info_is_used(self.info) }
+ }
+
+ /// Get the GPIO line's consumer name.
+ pub fn consumer(&self) -> Result<&str> {
+ // SAFETY: The string returned by libgpiod is guaranteed to live as long
+ // as the `struct Info`.
+ let name = unsafe { gpiod::gpiod_line_info_get_consumer(self.info) };
+ if name.is_null() {
+ return Err(Error::NullString("GPIO line's consumer name"));
+ }
+
+ // SAFETY: The string is guaranteed to be valid here by the C API.
+ unsafe { CStr::from_ptr(name) }
+ .to_str()
+ .map_err(Error::StringNotUtf8)
+ }
+
+ /// Get the GPIO line's direction.
+ pub fn direction(&self) -> Result<Direction> {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ Direction::new(unsafe { gpiod::gpiod_line_info_get_direction(self.info) } as u32)
+ }
+
+ /// Returns true if the line is "active-low", false otherwise.
+ pub fn is_active_low(&self) -> bool {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_info_is_active_low(self.info) }
+ }
+
+ /// Get the GPIO line's bias setting.
+ pub fn bias(&self) -> Result<Option<Bias>> {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ Bias::new(unsafe { gpiod::gpiod_line_info_get_bias(self.info) } as u32)
+ }
+
+ /// Get the GPIO line's drive setting.
+ pub fn drive(&self) -> Result<Drive> {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ Drive::new(unsafe { gpiod::gpiod_line_info_get_drive(self.info) } as u32)
+ }
+
+ /// Get the current edge detection setting of the line.
+ pub fn edge_detection(&self) -> Result<Option<Edge>> {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ Edge::new(unsafe { gpiod::gpiod_line_info_get_edge_detection(self.info) } as u32)
+ }
+
+ /// Get the current event clock setting used for edge event timestamps.
+ pub fn event_clock(&self) -> Result<EventClock> {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ EventClock::new(unsafe { gpiod::gpiod_line_info_get_event_clock(self.info) } as u32)
+ }
+
+ /// Returns true if the line is debounced (either by hardware or by the
+ /// kernel software debouncer), false otherwise.
+ pub fn is_debounced(&self) -> bool {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_info_is_debounced(self.info) }
+ }
+
+ /// Get the debounce period of the line.
+ pub fn debounce_period(&self) -> Duration {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ Duration::from_micros(unsafe {
+ gpiod::gpiod_line_info_get_debounce_period_us(self.info) as u64
+ })
+ }
+}
+
+impl Drop for Info {
+ fn drop(&mut self) {
+ // We must not free the Line info object created from `struct chip::Event` by calling
+ // libgpiod API.
+ if !self.contained {
+ // SAFETY: `gpiod_line_info` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_info_free(self.info) }
+ }
+ }
+}
new file mode 100644
@@ -0,0 +1,226 @@
+// SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause
+// SPDX-FileCopyrightText: 2022 Linaro Ltd.
+// SPDX-FileCopyrightTest: 2022 Viresh Kumar <viresh.kumar@linaro.org>
+
+use std::os::{raw::c_ulong, unix::prelude::AsRawFd};
+use std::time::Duration;
+
+use super::{
+ gpiod,
+ line::{self, Offset, Value, ValueMap},
+ request, Error, OperationType, Result,
+};
+
+/// Line request operations
+///
+/// Allows interaction with a set of requested lines.
+#[derive(Debug, Eq, PartialEq)]
+pub struct Request {
+ pub(crate) request: *mut gpiod::gpiod_line_request,
+}
+
+impl Request {
+ /// Request a set of lines for exclusive usage.
+ pub(crate) fn new(request: *mut gpiod::gpiod_line_request) -> Result<Self> {
+ Ok(Self { request })
+ }
+
+ /// Get the number of lines in the request.
+ pub fn num_lines(&self) -> usize {
+ // SAFETY: `gpiod_line_request` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_request_get_num_lines(self.request) as usize }
+ }
+
+ /// Get the offsets of lines in the request.
+ pub fn offsets(&self) -> Vec<Offset> {
+ let mut offsets = vec![0; self.num_lines() as usize];
+
+ // SAFETY: `gpiod_line_request` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_request_get_offsets(self.request, offsets.as_mut_ptr()) };
+ offsets
+ }
+
+ /// Get the value (0 or 1) of a single line associated with the request.
+ pub fn value(&self, offset: Offset) -> Result<Value> {
+ // SAFETY: `gpiod_line_request` is guaranteed to be valid here.
+ let value = unsafe { gpiod::gpiod_line_request_get_value(self.request, offset) };
+
+ if value != 0 && value != 1 {
+ Err(Error::OperationFailed(
+ OperationType::LineRequestGetVal,
+ errno::errno(),
+ ))
+ } else {
+ Value::new(value)
+ }
+ }
+
+ /// Get values of a subset of lines associated with the request.
+ pub fn values_subset(&self, offsets: &[Offset]) -> Result<ValueMap> {
+ let mut values = vec![0; offsets.len()];
+
+ // SAFETY: `gpiod_line_request` is guaranteed to be valid here.
+ let ret = unsafe {
+ gpiod::gpiod_line_request_get_values_subset(
+ self.request,
+ offsets.len() as c_ulong,
+ offsets.as_ptr(),
+ values.as_mut_ptr(),
+ )
+ };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineRequestGetValSubset,
+ errno::errno(),
+ ))
+ } else {
+ let mut map = ValueMap::new();
+
+ for (i, val) in values.iter().enumerate() {
+ map.insert(offsets[i].into(), Value::new(*val)?);
+ }
+
+ Ok(map)
+ }
+ }
+
+ /// Get values of all lines associated with the request.
+ pub fn values(&self) -> Result<ValueMap> {
+ self.values_subset(&self.offsets())
+ }
+
+ /// Set the value of a single line associated with the request.
+ pub fn set_value(&self, offset: Offset, value: Value) -> Result<()> {
+ // SAFETY: `gpiod_line_request` is guaranteed to be valid here.
+ let ret =
+ unsafe { gpiod::gpiod_line_request_set_value(self.request, offset, value.value()) };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineRequestSetVal,
+ errno::errno(),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ /// Get values of a subset of lines associated with the request.
+ pub fn set_values_subset(&self, map: ValueMap) -> Result<()> {
+ let mut offsets = Vec::new();
+ let mut values = Vec::new();
+
+ for (offset, value) in map {
+ offsets.push(offset as u32);
+ values.push(value.value());
+ }
+
+ // SAFETY: `gpiod_line_request` is guaranteed to be valid here.
+ let ret = unsafe {
+ gpiod::gpiod_line_request_set_values_subset(
+ self.request,
+ offsets.len() as c_ulong,
+ offsets.as_ptr(),
+ values.as_ptr(),
+ )
+ };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineRequestSetValSubset,
+ errno::errno(),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ /// Get values of all lines associated with the request.
+ pub fn set_values(&self, values: &[Value]) -> Result<()> {
+ if values.len() != self.num_lines() as usize {
+ return Err(Error::InvalidArguments);
+ }
+
+ let mut new_values = Vec::new();
+ for value in values {
+ new_values.push(value.value());
+ }
+
+ // SAFETY: `gpiod_line_request` is guaranteed to be valid here.
+ let ret =
+ unsafe { gpiod::gpiod_line_request_set_values(self.request, new_values.as_ptr()) };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineRequestSetVal,
+ errno::errno(),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ /// Update the configuration of lines associated with the line request.
+ pub fn reconfigure_lines(&self, lconfig: &line::Config) -> Result<()> {
+ // SAFETY: `gpiod_line_request` is guaranteed to be valid here.
+ let ret =
+ unsafe { gpiod::gpiod_line_request_reconfigure_lines(self.request, lconfig.config) };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineRequestReconfigLines,
+ errno::errno(),
+ ))
+ } else {
+ Ok(())
+ }
+ }
+
+ /// Wait for edge events on any of the lines associated with the request.
+ pub fn wait_edge_event(&self, timeout: Option<Duration>) -> Result<bool> {
+ let timeout = match timeout {
+ Some(x) => x.as_nanos() as i64,
+ // Block indefinitely
+ None => -1,
+ };
+
+ // SAFETY: `gpiod_line_request` is guaranteed to be valid here.
+ let ret = unsafe { gpiod::gpiod_line_request_wait_edge_event(self.request, timeout) };
+
+ match ret {
+ -1 => Err(Error::OperationFailed(
+ OperationType::LineRequestWaitEdgeEvent,
+ errno::errno(),
+ )),
+ 0 => Ok(false),
+ _ => Ok(true),
+ }
+ }
+
+ /// Get a number of edge events from a line request.
+ ///
+ /// This function will block if no event was queued for the line.
+ pub fn read_edge_events<'a>(
+ &'a self,
+ buffer: &'a mut request::Buffer,
+ ) -> Result<request::Events> {
+ buffer.read_edge_events(self)
+ }
+}
+
+impl AsRawFd for Request {
+ /// Get the file descriptor associated with the line request.
+ fn as_raw_fd(&self) -> i32 {
+ // SAFETY: `gpiod_line_request` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_request_get_fd(self.request) }
+ }
+}
+
+impl Drop for Request {
+ /// Release the requested lines and free all associated resources.
+ fn drop(&mut self) {
+ // SAFETY: `gpiod_line_request` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_request_release(self.request) }
+ }
+}
new file mode 100644
@@ -0,0 +1,296 @@
+// SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause
+// SPDX-FileCopyrightText: 2022 Linaro Ltd.
+// SPDX-FileCopyrightTest: 2022 Viresh Kumar <viresh.kumar@linaro.org>
+
+use std::time::Duration;
+
+use super::{
+ gpiod,
+ line::{Bias, Direction, Drive, Edge, EventClock, SettingKind, SettingVal, Value},
+ Error, OperationType, Result,
+};
+
+/// Line settings objects.
+///
+/// Line settings object contains a set of line properties that can be used
+/// when requesting lines or reconfiguring an existing request.
+///
+/// Mutators in general can only fail if the new property value is invalid. The
+/// return values can be safely ignored - the object remains valid even after
+/// a mutator fails and simply uses the sane default appropriate for given
+/// property.
+
+#[derive(Debug, Eq, PartialEq)]
+pub struct Settings {
+ pub(crate) settings: *mut gpiod::gpiod_line_settings,
+}
+
+impl Settings {
+ /// Create a new line settings object.
+ pub fn new() -> Result<Self> {
+ // SAFETY: The `gpiod_line_settings` returned by libgpiod is guaranteed to live as long
+ // as the `struct Settings`.
+ let settings = unsafe { gpiod::gpiod_line_settings_new() };
+
+ if settings.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::LineSettingsNew,
+ errno::errno(),
+ ));
+ }
+
+ Ok(Self { settings })
+ }
+
+ pub fn new_with_settings(settings: *mut gpiod::gpiod_line_settings) -> Self {
+ Self { settings }
+ }
+
+ /// Resets the line settings object to its default values.
+ pub fn reset(&mut self) {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_settings_reset(self.settings) }
+ }
+
+ /// Makes copy of the settings object.
+ pub fn settings_clone(&self) -> Result<Self> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ let settings = unsafe { gpiod::gpiod_line_settings_copy(self.settings) };
+ if settings.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::LineSettingsCopy,
+ errno::errno(),
+ ));
+ }
+
+ Ok(Self { settings })
+ }
+
+ /// Set line prop setting.
+ pub fn set_prop(&mut self, props: &[SettingVal]) -> Result<&mut Self> {
+ for property in props {
+ match property {
+ SettingVal::Direction(prop) => self.set_direction(*prop)?,
+ SettingVal::EdgeDetection(prop) => self.set_edge_detection(*prop)?,
+ SettingVal::Bias(prop) => self.set_bias(*prop)?,
+ SettingVal::Drive(prop) => self.set_drive(*prop)?,
+ SettingVal::ActiveLow(prop) => self.set_active_low(*prop),
+ SettingVal::DebouncePeriod(prop) => self.set_debounce_period(*prop),
+ SettingVal::EventClock(prop) => self.set_event_clock(*prop)?,
+ SettingVal::OutputValue(prop) => self.set_output_value(*prop)?,
+ };
+ }
+
+ Ok(self)
+ }
+
+ /// Get the line prop setting.
+ pub fn prop(&self, property: SettingKind) -> Result<SettingVal> {
+ Ok(match property {
+ SettingKind::Direction => SettingVal::Direction(self.direction()?),
+ SettingKind::EdgeDetection => SettingVal::EdgeDetection(self.edge_detection()?),
+ SettingKind::Bias => SettingVal::Bias(self.bias()?),
+ SettingKind::Drive => SettingVal::Drive(self.drive()?),
+ SettingKind::ActiveLow => SettingVal::ActiveLow(self.active_low()),
+ SettingKind::DebouncePeriod => SettingVal::DebouncePeriod(self.debounce_period()?),
+ SettingKind::EventClock => SettingVal::EventClock(self.event_clock()?),
+ SettingKind::OutputValue => SettingVal::OutputValue(self.output_value()?),
+ })
+ }
+
+ /// Set the line direction.
+ pub fn set_direction(&mut self, direction: Direction) -> Result<&mut Self> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ let ret = unsafe {
+ gpiod::gpiod_line_settings_set_direction(
+ self.settings,
+ direction.gpiod_direction() as i32,
+ )
+ };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineSettingsSetDirection,
+ errno::errno(),
+ ))
+ } else {
+ Ok(self)
+ }
+ }
+
+ /// Get the direction setting.
+ pub fn direction(&self) -> Result<Direction> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ Direction::new(unsafe { gpiod::gpiod_line_settings_get_direction(self.settings) } as u32)
+ }
+
+ /// Set the edge event detection setting.
+ pub fn set_edge_detection(&mut self, edge: Option<Edge>) -> Result<&mut Self> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ let ret = unsafe {
+ gpiod::gpiod_line_settings_set_edge_detection(
+ self.settings,
+ Edge::gpiod_edge(edge) as i32,
+ )
+ };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineSettingsSetEdgeDetection,
+ errno::errno(),
+ ))
+ } else {
+ Ok(self)
+ }
+ }
+
+ /// Get the edge event detection setting.
+ pub fn edge_detection(&self) -> Result<Option<Edge>> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ Edge::new(unsafe { gpiod::gpiod_line_settings_get_edge_detection(self.settings) } as u32)
+ }
+
+ /// Set the bias setting.
+ pub fn set_bias(&mut self, bias: Option<Bias>) -> Result<&mut Self> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ let ret = unsafe {
+ gpiod::gpiod_line_settings_set_bias(self.settings, Bias::gpiod_bias(bias) as i32)
+ };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineSettingsSetBias,
+ errno::errno(),
+ ))
+ } else {
+ Ok(self)
+ }
+ }
+
+ /// Get the bias setting.
+ pub fn bias(&self) -> Result<Option<Bias>> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ Bias::new(unsafe { gpiod::gpiod_line_settings_get_bias(self.settings) } as u32)
+ }
+
+ /// Set the drive setting.
+ pub fn set_drive(&mut self, drive: Drive) -> Result<&mut Self> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ let ret = unsafe {
+ gpiod::gpiod_line_settings_set_drive(self.settings, drive.gpiod_drive() as i32)
+ };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineSettingsSetDrive,
+ errno::errno(),
+ ))
+ } else {
+ Ok(self)
+ }
+ }
+
+ /// Get the drive setting.
+ pub fn drive(&self) -> Result<Drive> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ Drive::new(unsafe { gpiod::gpiod_line_settings_get_drive(self.settings) } as u32)
+ }
+
+ /// Set active-low setting.
+ pub fn set_active_low(&mut self, active_low: bool) -> &mut Self {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ unsafe {
+ gpiod::gpiod_line_settings_set_active_low(self.settings, active_low);
+ }
+ self
+ }
+
+ /// Check the active-low setting.
+ pub fn active_low(&self) -> bool {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_settings_get_active_low(self.settings) }
+ }
+
+ /// Set the debounce period setting.
+ pub fn set_debounce_period(&mut self, period: Duration) -> &mut Self {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ unsafe {
+ gpiod::gpiod_line_settings_set_debounce_period_us(
+ self.settings,
+ period.as_micros().try_into().unwrap(),
+ );
+ }
+
+ self
+ }
+
+ /// Get the debounce period.
+ pub fn debounce_period(&self) -> Result<Duration> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ Ok(Duration::from_micros(unsafe {
+ gpiod::gpiod_line_settings_get_debounce_period_us(self.settings) as u64
+ }))
+ }
+
+ /// Set the event clock setting.
+ pub fn set_event_clock(&mut self, clock: EventClock) -> Result<&mut Self> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ let ret = unsafe {
+ gpiod::gpiod_line_settings_set_event_clock(self.settings, clock.gpiod_clock() as i32)
+ };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineSettingsSetEventClock,
+ errno::errno(),
+ ))
+ } else {
+ Ok(self)
+ }
+ }
+
+ /// Get the event clock setting.
+ pub fn event_clock(&self) -> Result<EventClock> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ EventClock::new(unsafe { gpiod::gpiod_line_settings_get_event_clock(self.settings) } as u32)
+ }
+
+ /// Set the output value setting.
+ pub fn set_output_value(&mut self, value: Value) -> Result<&mut Self> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ let ret =
+ unsafe { gpiod::gpiod_line_settings_set_output_value(self.settings, value.value()) };
+
+ if ret == -1 {
+ Err(Error::OperationFailed(
+ OperationType::LineSettingsSetOutputValue,
+ errno::errno(),
+ ))
+ } else {
+ Ok(self)
+ }
+ }
+
+ /// Get the output value, 0 or 1.
+ pub fn output_value(&self) -> Result<Value> {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ let value = unsafe { gpiod::gpiod_line_settings_get_output_value(self.settings) };
+
+ if value != 0 && value != 1 {
+ Err(Error::OperationFailed(
+ OperationType::LineSettingsGetOutVal,
+ errno::errno(),
+ ))
+ } else {
+ Value::new(value)
+ }
+ }
+}
+
+impl Drop for Settings {
+ /// Free the line settings object and release all associated resources.
+ fn drop(&mut self) {
+ // SAFETY: `gpiod_line_settings` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_line_settings_free(self.settings) }
+ }
+}
new file mode 100644
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause
+// SPDX-FileCopyrightText: 2022 Linaro Ltd.
+// SPDX-FileCopyrightTest: 2022 Viresh Kumar <viresh.kumar@linaro.org>
+
+use std::ffi::{CStr, CString};
+use std::os::raw::{c_char, c_ulong};
+use std::str;
+
+use super::{gpiod, Error, OperationType, Result};
+
+/// Request configuration objects
+///
+/// Request config objects are used to pass a set of options to the kernel at
+/// the time of the line request. The mutators don't return error values. If the
+/// values are invalid, in general they are silently adjusted to acceptable
+/// ranges.
+
+#[derive(Debug, Eq, PartialEq)]
+pub struct Config {
+ pub(crate) config: *mut gpiod::gpiod_request_config,
+}
+
+impl Config {
+ /// Create a new request config object.
+ pub fn new() -> Result<Self> {
+ // SAFETY: The `gpiod_request_config` returned by libgpiod is guaranteed to live as long
+ // as the `struct Config`.
+ let config = unsafe { gpiod::gpiod_request_config_new() };
+ if config.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::RequestConfigNew,
+ errno::errno(),
+ ));
+ }
+
+ Ok(Self { config })
+ }
+
+ /// Set the consumer name for the request.
+ ///
+ /// If the consumer string is too long, it will be truncated to the max
+ /// accepted length.
+ pub fn set_consumer(&self, consumer: &str) -> Result<()> {
+ let consumer = CString::new(consumer).map_err(|_| Error::InvalidString)?;
+
+ // SAFETY: `gpiod_request_config` is guaranteed to be valid here.
+ unsafe {
+ gpiod::gpiod_request_config_set_consumer(
+ self.config,
+ consumer.as_ptr() as *const c_char,
+ )
+ }
+
+ Ok(())
+ }
+
+ /// Get the consumer name configured in the request config.
+ pub fn consumer(&self) -> Result<&str> {
+ // SAFETY: The string returned by libgpiod is guaranteed to live as long
+ // as the `struct Config`.
+ let consumer = unsafe { gpiod::gpiod_request_config_get_consumer(self.config) };
+ if consumer.is_null() {
+ return Err(Error::OperationFailed(
+ OperationType::RequestConfigGetConsumer,
+ errno::errno(),
+ ));
+ }
+
+ // SAFETY: The string is guaranteed to be valid here by the C API.
+ unsafe { CStr::from_ptr(consumer) }
+ .to_str()
+ .map_err(Error::StringNotUtf8)
+ }
+
+ /// Set the size of the kernel event buffer for the request.
+ pub fn set_event_buffer_size(&self, size: usize) {
+ // SAFETY: `gpiod_request_config` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_request_config_set_event_buffer_size(self.config, size as c_ulong) }
+ }
+
+ /// Get the edge event buffer size setting for the request config.
+ pub fn event_buffer_size(&self) -> usize {
+ // SAFETY: `gpiod_request_config` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_request_config_get_event_buffer_size(self.config) as usize }
+ }
+}
+
+impl Drop for Config {
+ /// Free the request config object and release all associated resources.
+ fn drop(&mut self) {
+ // SAFETY: `gpiod_request_config` is guaranteed to be valid here.
+ unsafe { gpiod::gpiod_request_config_free(self.config) }
+ }
+}