Merge #63

63: Update embedded-hal to version 1.0.0-alpha.5 r=ryankurte a=eldruin

I will add support for embedded-hal 0.2.x in parallel as described [here](https://github.com/rust-embedded/embedded-hal#adding-support-for-an-embedded-hal--alpha-version-in-a-hal-implementation). This PR contains some preparation for that.

Co-authored-by: Diego Barrios Romero <eldruin@gmail.com>

Author: bors[bot]

.github/bors.toml

@@ -4,5 +4,5 @@ required_approvals = 1
 status = [
   "CI (stable, x86_64-unknown-linux-gnu)",
   "CI (stable, armv7-unknown-linux-gnueabihf)",
-  "CI (1.36.0, x86_64-unknown-linux-gnu)",
+  "CI (1.46.0, x86_64-unknown-linux-gnu)",
 ]

.github/workflows/ci.yml

@@ -21,7 +21,7 @@ jobs:
 
         include:
           # Test MSRV
-          - rust: 1.36.0
+          - rust: 1.46.0
             TARGET: x86_64-unknown-linux-gnu
 
           # Test nightly but don't fail

CHANGELOG.md

@@ -12,8 +12,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Modified `OutputPin` behavior for active-low pins to match `InputPin` behavior.
 - Set default features to build both sysfs and cdev pin types.
 - Removed `Pin` export, use `CdevPin` or `SysfsPin`.
-- Increased the Minimum Supported Rust Version to `1.36.0` due to an update of `gpio_cdev`.
-- Adapted to `embedded-hal` `1.0.0-alpha.3` release.
+- Increased the Minimum Supported Rust Version to `1.46.0` due to an update of `bitflags`.
+- Adapted to `embedded-hal` `1.0.0-alpha.5` release.
 - Updated `nb` to version `1`.
 
 ## [v0.3.0] - 2019-11-25

Cargo.toml

@@ -20,20 +20,20 @@ async-tokio = ["gpio-cdev/async-tokio"]
 default = [ "gpio_cdev", "gpio_sysfs" ]
 
 [dependencies]
-embedded-hal = "=1.0.0-alpha.4"
-gpio-cdev = { version = "0.4", optional = true }
-sysfs_gpio = { version = "0.5", optional = true }
+embedded-hal = "=1.0.0-alpha.5"
+gpio-cdev = { version = "0.5", optional = true }
+sysfs_gpio = { version = "0.6", optional = true }
 
-i2cdev = "0.4.3"
+i2cdev = "0.5"
 nb = "1"
 serial-core = "0.4.0"
 serial-unix = "0.4.0"
-spidev = "0.4"
+spidev = "0.5"
 
 [dev-dependencies]
 openpty = "0.1.0"
 
 [dependencies.cast]
 # we don't need the `Error` implementation
 default-features = false
-version = "0.2.2"
+version = "0.3"

README.md

@@ -27,7 +27,7 @@ linux-embedded-hal = { version = "0.3", features = ["gpio_cdev"] }
 
 ## Minimum Supported Rust Version (MSRV)
 
-This crate is guaranteed to compile on stable Rust 1.36.0 and up. It *might*
+This crate is guaranteed to compile on stable Rust 1.46.0 and up. It *might*
 compile with older versions but that may change in any new patch release.
 
 ## License

examples/transactional-i2c.rs

@@ -1,6 +1,4 @@
-extern crate embedded_hal;
-extern crate linux_embedded_hal;
-use embedded_hal::blocking::i2c::{Operation as I2cOperation, Transactional};
+use embedded_hal::i2c::blocking::{Operation as I2cOperation, Transactional};
 use linux_embedded_hal::I2cdev;
 
 const ADDR: u8 = 0x12;
@@ -23,7 +21,7 @@ where
             I2cOperation::Write(&[0xAB]),
             I2cOperation::Read(&mut read_buffer),
         ];
-        self.i2c.try_exec(ADDR, &mut ops).and(Ok(read_buffer[0]))
+        self.i2c.exec(ADDR, &mut ops).and(Ok(read_buffer[0]))
     }
 }
 

src/cdev_pin.rs

@@ -1,4 +1,6 @@
-//! Linux CDev pin type
+//! Implementation of [`embedded-hal`] digital input/output traits using a Linux CDev pin
+//!
+//! [`embedded-hal`]: https://docs.rs/embedded-hal
 
 /// Newtype around [`gpio_cdev::LineHandle`] that implements the `embedded-hal` traits
 ///
@@ -15,18 +17,18 @@ impl CdevPin {
     }
 }
 
-impl embedded_hal::digital::OutputPin for CdevPin {
+impl embedded_hal::digital::blocking::OutputPin for CdevPin {
     type Error = gpio_cdev::errors::Error;
 
-    fn try_set_low(&mut self) -> Result<(), Self::Error> {
+    fn set_low(&mut self) -> Result<(), Self::Error> {
         if self.1 {
             self.0.set_value(1)
         } else {
             self.0.set_value(0)
         }
     }
 
-    fn try_set_high(&mut self) -> Result<(), Self::Error> {
+    fn set_high(&mut self) -> Result<(), Self::Error> {
         if self.1 {
             self.0.set_value(0)
         } else {
@@ -35,19 +37,19 @@ impl embedded_hal::digital::OutputPin for CdevPin {
     }
 }
 
-impl embedded_hal::digital::InputPin for CdevPin {
+impl embedded_hal::digital::blocking::InputPin for CdevPin {
     type Error = gpio_cdev::errors::Error;
 
-    fn try_is_high(&self) -> Result<bool, Self::Error> {
+    fn is_high(&self) -> Result<bool, Self::Error> {
         if !self.1 {
             self.0.get_value().map(|val| val != 0)
         } else {
             self.0.get_value().map(|val| val == 0)
         }
     }
 
-    fn try_is_low(&self) -> Result<bool, Self::Error> {
-        self.try_is_high().map(|val| !val)
+    fn is_low(&self) -> Result<bool, Self::Error> {
+        self.is_high().map(|val| !val)
     }
 }
 

src/delay.rs

@@ -0,0 +1,90 @@
+//! Implementation of [`embedded-hal`] delay traits
+//!
+//! [`embedded-hal`]: https://docs.rs/embedded-hal
+
+use cast::{u32, u64};
+use core::convert::Infallible;
+use embedded_hal::delay::blocking::{DelayMs, DelayUs};
+use std::thread;
+use std::time::Duration;
+
+/// Empty struct that provides delay functionality on top of `thread::sleep`
+pub struct Delay;
+
+impl DelayUs<u8> for Delay {
+    type Error = Infallible;
+
+    fn delay_us(&mut self, n: u8) -> Result<(), Self::Error> {
+        thread::sleep(Duration::new(0, u32(n) * 1000));
+        Ok(())
+    }
+}
+
+impl DelayUs<u16> for Delay {
+    type Error = Infallible;
+
+    fn delay_us(&mut self, n: u16) -> Result<(), Self::Error> {
+        thread::sleep(Duration::new(0, u32(n) * 1000));
+        Ok(())
+    }
+}
+
+impl DelayUs<u32> for Delay {
+    type Error = Infallible;
+
+    fn delay_us(&mut self, n: u32) -> Result<(), Self::Error> {
+        let secs = n / 1_000_000;
+        let nsecs = (n % 1_000_000) * 1_000;
+
+        thread::sleep(Duration::new(u64(secs), nsecs));
+        Ok(())
+    }
+}
+
+impl DelayUs<u64> for Delay {
+    type Error = Infallible;
+
+    fn delay_us(&mut self, n: u64) -> Result<(), Self::Error> {
+        let secs = n / 1_000_000;
+        let nsecs = ((n % 1_000_000) * 1_000) as u32;
+
+        thread::sleep(Duration::new(secs, nsecs));
+        Ok(())
+    }
+}
+
+impl DelayMs<u8> for Delay {
+    type Error = Infallible;
+
+    fn delay_ms(&mut self, n: u8) -> Result<(), Self::Error> {
+        thread::sleep(Duration::from_millis(u64(n)));
+        Ok(())
+    }
+}
+
+impl DelayMs<u16> for Delay {
+    type Error = Infallible;
+
+    fn delay_ms(&mut self, n: u16) -> Result<(), Self::Error> {
+        thread::sleep(Duration::from_millis(u64(n)));
+        Ok(())
+    }
+}
+
+impl DelayMs<u32> for Delay {
+    type Error = Infallible;
+
+    fn delay_ms(&mut self, n: u32) -> Result<(), Self::Error> {
+        thread::sleep(Duration::from_millis(u64(n)));
+        Ok(())
+    }
+}
+
+impl DelayMs<u64> for Delay {
+    type Error = Infallible;
+
+    fn delay_ms(&mut self, n: u64) -> Result<(), Self::Error> {
+        thread::sleep(Duration::from_millis(n));
+        Ok(())
+    }
+}

src/i2c.rs

@@ -0,0 +1,119 @@
+//! Implementation of [`embedded-hal`] I2C traits
+//!
+//! [`embedded-hal`]: https://docs.rs/embedded-hal
+
+use std::ops;
+use std::path::{Path, PathBuf};
+
+/// Newtype around [`i2cdev::linux::LinuxI2CDevice`] that implements the `embedded-hal` traits
+///
+/// [`i2cdev::linux::LinuxI2CDevice`]: https://docs.rs/i2cdev/0.3.1/i2cdev/linux/struct.LinuxI2CDevice.html
+pub struct I2cdev {
+    inner: i2cdev::linux::LinuxI2CDevice,
+    path: PathBuf,
+    address: Option<u8>,
+}
+
+impl I2cdev {
+    /// See [`i2cdev::linux::LinuxI2CDevice::new`][0] for details.
+    ///
+    /// [0]: https://docs.rs/i2cdev/0.3.1/i2cdev/linux/struct.LinuxI2CDevice.html#method.new
+    pub fn new<P>(path: P) -> Result<Self, i2cdev::linux::LinuxI2CError>
+    where
+        P: AsRef<Path>,
+    {
+        let dev = I2cdev {
+            path: path.as_ref().to_path_buf(),
+            inner: i2cdev::linux::LinuxI2CDevice::new(path, 0)?,
+            address: None,
+        };
+        Ok(dev)
+    }
+
+    fn set_address(&mut self, address: u8) -> Result<(), i2cdev::linux::LinuxI2CError> {
+        if self.address != Some(address) {
+            self.inner = i2cdev::linux::LinuxI2CDevice::new(&self.path, u16::from(address))?;
+            self.address = Some(address);
+        }
+        Ok(())
+    }
+}
+
+impl ops::Deref for I2cdev {
+    type Target = i2cdev::linux::LinuxI2CDevice;
+
+    fn deref(&self) -> &Self::Target {
+        &self.inner
+    }
+}
+
+impl ops::DerefMut for I2cdev {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.inner
+    }
+}
+
+mod embedded_hal_impl {
+    use super::*;
+    use embedded_hal::i2c::blocking::{
+        Operation as I2cOperation, Read, Transactional, Write, WriteRead,
+    };
+    use i2cdev::core::{I2CDevice, I2CMessage, I2CTransfer};
+    use i2cdev::linux::LinuxI2CMessage;
+
+    impl Read for I2cdev {
+        type Error = i2cdev::linux::LinuxI2CError;
+
+        fn read(&mut self, address: u8, buffer: &mut [u8]) -> Result<(), Self::Error> {
+            self.set_address(address)?;
+            self.inner.read(buffer)
+        }
+    }
+
+    impl Write for I2cdev {
+        type Error = i2cdev::linux::LinuxI2CError;
+
+        fn write(&mut self, address: u8, bytes: &[u8]) -> Result<(), Self::Error> {
+            self.set_address(address)?;
+            self.inner.write(bytes)
+        }
+    }
+
+    impl WriteRead for I2cdev {
+        type Error = i2cdev::linux::LinuxI2CError;
+
+        fn write_read(
+            &mut self,
+            address: u8,
+            bytes: &[u8],
+            buffer: &mut [u8],
+        ) -> Result<(), Self::Error> {
+            self.set_address(address)?;
+            let mut messages = [LinuxI2CMessage::write(bytes), LinuxI2CMessage::read(buffer)];
+            self.inner.transfer(&mut messages).map(drop)
+        }
+    }
+
+    impl Transactional for I2cdev {
+        type Error = i2cdev::linux::LinuxI2CError;
+
+        fn exec(
+            &mut self,
+            address: u8,
+            operations: &mut [I2cOperation],
+        ) -> Result<(), Self::Error> {
+            // Map operations from generic to linux objects
+            let mut messages: Vec<_> = operations
+                .as_mut()
+                .iter_mut()
+                .map(|a| match a {
+                    I2cOperation::Write(w) => LinuxI2CMessage::write(w),
+                    I2cOperation::Read(r) => LinuxI2CMessage::read(r),
+                })
+                .collect();
+
+            self.set_address(address)?;
+            self.inner.transfer(&mut messages).map(drop)
+        }
+    }
+}