This adds gpiosim rust crate, which provides helpers to emulate GPIO chips.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- bindings/rust/Cargo.toml | 1 + bindings/rust/gpiosim/Cargo.toml | 22 ++ bindings/rust/gpiosim/build.rs | 43 ++++ bindings/rust/gpiosim/src/lib.rs | 79 ++++++++ bindings/rust/gpiosim/src/sim.rs | 331 +++++++++++++++++++++++++++++++ 5 files changed, 476 insertions(+) create mode 100644 bindings/rust/gpiosim/Cargo.toml create mode 100644 bindings/rust/gpiosim/build.rs create mode 100644 bindings/rust/gpiosim/src/lib.rs create mode 100644 bindings/rust/gpiosim/src/sim.rs
diff --git a/bindings/rust/Cargo.toml b/bindings/rust/Cargo.toml index c7bbcc798920..b9eea6b3a5ea 100644 --- a/bindings/rust/Cargo.toml +++ b/bindings/rust/Cargo.toml @@ -1,5 +1,6 @@ [workspace]
members = [ + "gpiosim", "libgpiod-sys" ] diff --git a/bindings/rust/gpiosim/Cargo.toml b/bindings/rust/gpiosim/Cargo.toml new file mode 100644 index 000000000000..f8f7e7f79b77 --- /dev/null +++ b/bindings/rust/gpiosim/Cargo.toml @@ -0,0 +1,22 @@ +[package] +name = "gpiosim" +version = "0.1.0" +authors = ["Viresh Kumar viresh.kumar@linaro.org"] +description = "gpiosim header bindings" +repository = "https://git.kernel.org/pub/scm/libs/libgpiod/libgpiod.git" +categories = ["external-ffi-bindings", "os::linux-apis"] +rust-version = "1.56" +keywords = ["libgpiod", "gpio", "gpiosim"] +license = "Apache-2.0 OR BSD-3-Clause" +edition = "2021" + +[dependencies] +errno = "0.2.8" +libgpiod = { path = "../libgpiod" } + +[features] +generate = [ "bindgen" ] + +[build-dependencies] +bindgen = { version = "0.59.1", optional = true } +cc = "1.0.46" diff --git a/bindings/rust/gpiosim/build.rs b/bindings/rust/gpiosim/build.rs new file mode 100644 index 000000000000..460fb8c092c3 --- /dev/null +++ b/bindings/rust/gpiosim/build.rs @@ -0,0 +1,43 @@ +#[cfg(feature = "generate")] +extern crate bindgen; +#[cfg(feature = "generate")] +use std::env; +#[cfg(feature = "generate")] +use std::path::PathBuf; + +#[cfg(feature = "generate")] +fn generate_bindings() { + // Tell cargo to invalidate the built crate whenever following files change + println!("cargo:rerun-if-changed=../../../tests/gpiosim/gpiosim.h"); + + // The bindgen::Builder is the main entry point + // to bindgen, and lets you build up options for + // the resulting bindings. + let bindings = bindgen::Builder::default() + // The input header we would like to generate + // bindings for. + .header("../../../tests/gpiosim/gpiosim.h") + // Tell cargo to invalidate the built crate whenever any of the + // included header files changed. + .parse_callbacks(Box::new(bindgen::CargoCallbacks)) + // Finish the builder and generate the bindings. + .generate() + // Unwrap the Result and panic on failure. + .expect("Unable to generate bindings"); + + // Write the bindings to the $OUT_DIR/bindings.rs file. + let out_path = PathBuf::from(env::var("OUT_DIR").unwrap()); + bindings + .write_to_file(out_path.join("bindings.rs")) + .expect("Couldn't write bindings!"); +} + +fn main() { + #[cfg(feature = "generate")] + generate_bindings(); + + println!("cargo:rustc-link-lib=kmod"); + println!("cargo:rustc-link-lib=mount"); + println!("cargo:rustc-link-search=./../../tests/gpiosim/.libs/"); + println!("cargo:rustc-link-lib=static=gpiosim"); +} diff --git a/bindings/rust/gpiosim/src/lib.rs b/bindings/rust/gpiosim/src/lib.rs new file mode 100644 index 000000000000..e76870e4a094 --- /dev/null +++ b/bindings/rust/gpiosim/src/lib.rs @@ -0,0 +1,79 @@ +// SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause +// +// Copyright 2022 Linaro Ltd. All Rights Reserved. +// Viresh Kumar viresh.kumar@linaro.org + +use libgpiod::{Error, Result}; + +#[allow(non_camel_case_types, non_upper_case_globals)] +#[cfg_attr(test, allow(deref_nullptr, non_snake_case))] +#[allow(dead_code)] +mod bindings_raw { + #[cfg(feature = "generate")] + include!(concat!(env!("OUT_DIR"), "/bindings.rs")); + + #[cfg(not(feature = "generate"))] + include!("bindings.rs"); +} +use bindings_raw::*; + +mod sim; +pub use sim::*; + +/// Value settings. +#[derive(Copy, Clone, Debug, Eq, PartialEq)] +pub enum Value { + /// Active + Active, + /// Inactive + InActive, +} + +impl Value { + pub(crate) fn new(val: u32) -> Result<Self> { + match val { + GPIOSIM_VALUE_INACTIVE => Ok(Value::InActive), + GPIOSIM_VALUE_ACTIVE => Ok(Value::Active), + _ => Err(Error::InvalidEnumValue("Value", val as u32)), + } + } +} + +/// Direction settings. +#[derive(Copy, Clone, Debug, Eq, PartialEq)] +pub enum Direction { + /// Direction is input - for reading the value of an externally driven GPIO line. + Input, + /// Direction is output - for driving the GPIO line, value is high. + OutputHigh, + /// Direction is output - for driving the GPIO line, value is low. + OutputLow, +} + +impl Direction { + fn val(self) -> i32 { + (match self { + Direction::Input => GPIOSIM_HOG_DIR_INPUT, + Direction::OutputHigh => GPIOSIM_HOG_DIR_OUTPUT_HIGH, + Direction::OutputLow => GPIOSIM_HOG_DIR_OUTPUT_LOW, + }) as i32 + } +} + +/// Internal pull settings. +#[derive(Copy, Clone, Debug, Eq, PartialEq)] +pub enum Pull { + /// The internal pull-up is enabled. + Up, + /// The internal pull-down is enabled. + Down, +} + +impl Pull { + fn val(self) -> i32 { + (match self { + Pull::Up => GPIOSIM_PULL_UP, + Pull::Down => GPIOSIM_PULL_DOWN, + }) as i32 + } +} diff --git a/bindings/rust/gpiosim/src/sim.rs b/bindings/rust/gpiosim/src/sim.rs new file mode 100644 index 000000000000..6cafda0d90e2 --- /dev/null +++ b/bindings/rust/gpiosim/src/sim.rs @@ -0,0 +1,331 @@ +// SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause +// +// Copyright 2022 Linaro Ltd. All Rights Reserved. +// Viresh Kumar viresh.kumar@linaro.org + +use std::ffi::{CStr, CString}; +use std::os::raw::c_char; +use std::path::PathBuf; +use std::str; + +use libgpiod::{line::Offset, Error, OperationType, Result}; + +use crate::*; + +/// Sim Ctx +#[derive(Debug)] +struct SimCtx { + ctx: *mut gpiosim_ctx, +} + +// Safe as the pointer is guaranteed to be valid and the associated resource +// won't be freed until the object is dropped. +unsafe impl Send for SimCtx {} + +impl SimCtx { + fn new() -> Result<Self> { + // SAFETY: `gpiosim_ctx` returned by gpiosim is guaranteed to live + // as long as the `struct SimCtx`. + let ctx = unsafe { gpiosim_ctx_new() }; + if ctx.is_null() { + return Err(Error::OperationFailed( + OperationType::SimCtxNew, + errno::errno(), + )); + } + + Ok(Self { ctx }) + } +} + +impl Drop for SimCtx { + fn drop(&mut self) { + // SAFETY: `gpiosim_ctx` is guaranteed to be valid here. + unsafe { gpiosim_ctx_unref(self.ctx) } + } +} + +/// Sim Dev +#[derive(Debug)] +struct SimDev { + dev: *mut gpiosim_dev, +} + +// Safe as the pointer is guaranteed to be valid and the associated resource +// won't be freed until the object is dropped. +unsafe impl Send for SimDev {} + +impl SimDev { + fn new(ctx: &SimCtx) -> Result<Self> { + // SAFETY: `gpiosim_dev` returned by gpiosim is guaranteed to live + // as long as the `struct SimDev`. + let dev = unsafe { gpiosim_dev_new(ctx.ctx) }; + if dev.is_null() { + return Err(Error::OperationFailed( + OperationType::SimDevNew, + errno::errno(), + )); + } + + Ok(Self { dev }) + } + + fn enable(&self) -> Result<()> { + // SAFETY: `gpiosim_dev` is guaranteed to be valid here. + let ret = unsafe { gpiosim_dev_enable(self.dev) }; + + if ret == -1 { + Err(Error::OperationFailed( + OperationType::SimDevEnable, + errno::errno(), + )) + } else { + Ok(()) + } + } + + fn disable(&self) -> Result<()> { + // SAFETY: `gpiosim_dev` is guaranteed to be valid here. + let ret = unsafe { gpiosim_dev_disable(self.dev) }; + + if ret == -1 { + Err(Error::OperationFailed( + OperationType::SimDevDisable, + errno::errno(), + )) + } else { + Ok(()) + } + } +} + +impl Drop for SimDev { + fn drop(&mut self) { + // SAFETY: `gpiosim_dev` is guaranteed to be valid here. + unsafe { gpiosim_dev_unref(self.dev) } + } +} + +/// Sim Bank +#[derive(Debug)] +struct SimBank { + bank: *mut gpiosim_bank, +} + +// Safe as the pointer is guaranteed to be valid and the associated resource +// won't be freed until the object is dropped. +unsafe impl Send for SimBank {} + +impl SimBank { + fn new(dev: &SimDev) -> Result<Self> { + // SAFETY: `gpiosim_bank` returned by gpiosim is guaranteed to live + // as long as the `struct SimBank`. + let bank = unsafe { gpiosim_bank_new(dev.dev) }; + if bank.is_null() { + return Err(Error::OperationFailed( + OperationType::SimBankNew, + errno::errno(), + )); + } + + Ok(Self { bank }) + } + + fn chip_name(&self) -> Result<&str> { + // SAFETY: The string returned by gpiosim is guaranteed to live as long + // as the `struct SimBank`. + let name = unsafe { gpiosim_bank_get_chip_name(self.bank) }; + + // SAFETY: The string is guaranteed to be valid here. + unsafe { CStr::from_ptr(name) } + .to_str() + .map_err(Error::StringNotUtf8) + } + + fn dev_path(&self) -> Result<PathBuf> { + // SAFETY: The string returned by gpiosim is guaranteed to live as long + // as the `struct SimBank`. + let path = unsafe { gpiosim_bank_get_dev_path(self.bank) }; + + // SAFETY: The string is guaranteed to be valid here. + let path = unsafe { CStr::from_ptr(path) } + .to_str() + .map_err(Error::StringNotUtf8)?; + + Ok(PathBuf::from(path)) + } + + fn val(&self, offset: Offset) -> Result<Value> { + // SAFETY: `gpiosim_bank` is guaranteed to be valid here. + let ret = unsafe { gpiosim_bank_get_value(self.bank, offset) }; + + if ret == -1 { + Err(Error::OperationFailed( + OperationType::SimBankGetVal, + errno::errno(), + )) + } else { + Value::new(ret as u32) + } + } + + fn set_label(&self, label: &str) -> Result<()> { + let label = CString::new(label).map_err(|_| Error::InvalidString)?; + + // SAFETY: `gpiosim_bank` is guaranteed to be valid here. + let ret = unsafe { gpiosim_bank_set_label(self.bank, label.as_ptr() as *const c_char) }; + + if ret == -1 { + Err(Error::OperationFailed( + OperationType::SimBankSetLabel, + errno::errno(), + )) + } else { + Ok(()) + } + } + + fn set_num_lines(&self, num: usize) -> Result<()> { + // SAFETY: `gpiosim_bank` is guaranteed to be valid here. + let ret = unsafe { gpiosim_bank_set_num_lines(self.bank, num.try_into().unwrap()) }; + if ret == -1 { + Err(Error::OperationFailed( + OperationType::SimBankSetNumLines, + errno::errno(), + )) + } else { + Ok(()) + } + } + + fn set_line_name(&self, offset: Offset, name: &str) -> Result<()> { + let name = CString::new(name).map_err(|_| Error::InvalidString)?; + + // SAFETY: `gpiosim_bank` is guaranteed to be valid here. + let ret = unsafe { + gpiosim_bank_set_line_name(self.bank, offset, name.as_ptr() as *const c_char) + }; + + if ret == -1 { + Err(Error::OperationFailed( + OperationType::SimBankSetLineName, + errno::errno(), + )) + } else { + Ok(()) + } + } + + fn set_pull(&self, offset: Offset, pull: Pull) -> Result<()> { + // SAFETY: `gpiosim_bank` is guaranteed to be valid here. + let ret = unsafe { gpiosim_bank_set_pull(self.bank, offset, pull.val()) }; + + if ret == -1 { + Err(Error::OperationFailed( + OperationType::SimBankSetPull, + errno::errno(), + )) + } else { + Ok(()) + } + } + + fn hog_line(&self, offset: Offset, name: &str, dir: Direction) -> Result<()> { + let name = CString::new(name).map_err(|_| Error::InvalidString)?; + + // SAFETY: `gpiosim_bank` is guaranteed to be valid here. + let ret = unsafe { + gpiosim_bank_hog_line(self.bank, offset, name.as_ptr() as *const c_char, dir.val()) + }; + + if ret == -1 { + Err(Error::OperationFailed( + OperationType::SimBankHogLine, + errno::errno(), + )) + } else { + Ok(()) + } + } +} + +impl Drop for SimBank { + fn drop(&mut self) { + // SAFETY: `gpiosim_bank` is guaranteed to be valid here. + unsafe { gpiosim_bank_unref(self.bank) } + } +} + +/// GPIO SIM +#[derive(Debug)] +pub struct Sim { + _ctx: SimCtx, + dev: SimDev, + bank: SimBank, +} + +impl Sim { + pub fn new(ngpio: Option<usize>, label: Option<&str>, enable: bool) -> Result<Self> { + let ctx = SimCtx::new()?; + let dev = SimDev::new(&ctx)?; + let bank = SimBank::new(&dev)?; + + if let Some(ngpio) = ngpio { + bank.set_num_lines(ngpio)?; + } + + if let Some(label) = label { + bank.set_label(label)?; + } + + if enable { + dev.enable()?; + } + + Ok(Self { + _ctx: ctx, + dev, + bank, + }) + } + + pub fn chip_name(&self) -> &str { + self.bank.chip_name().unwrap() + } + + pub fn dev_path(&self) -> PathBuf { + self.bank.dev_path().unwrap() + } + + pub fn val(&self, offset: Offset) -> Result<Value> { + self.bank.val(offset) + } + + pub fn set_label(&self, label: &str) -> Result<()> { + self.bank.set_label(label) + } + + pub fn set_num_lines(&self, num: usize) -> Result<()> { + self.bank.set_num_lines(num) + } + + pub fn set_line_name(&self, offset: Offset, name: &str) -> Result<()> { + self.bank.set_line_name(offset, name) + } + + pub fn set_pull(&self, offset: Offset, pull: Pull) -> Result<()> { + self.bank.set_pull(offset, pull) + } + + pub fn hog_line(&self, offset: Offset, name: &str, dir: Direction) -> Result<()> { + self.bank.hog_line(offset, name, dir) + } + + pub fn enable(&self) -> Result<()> { + self.dev.enable() + } + + pub fn disable(&self) -> Result<()> { + self.dev.disable() + } +}