Move SysfsPin to its own module

The SysfsPin export can be enabled with feature flag "gpio_sysfs".

Author: almusil

Cargo.toml

@@ -8,11 +8,16 @@ name = "linux-embedded-hal"
 repository = "https://github.com/japaric/linux-embedded-hal"
 version = "0.3.0"
 
+[features]
+default = []
+gpio_sysfs = ["sysfs_gpio"]
+
 [dependencies]
 embedded-hal = { version = "0.2.3", features = ["unproven"] }
+sysfs_gpio = { version = "0.5", optional = true }
+
 i2cdev = "0.4.3"
 spidev = "0.4"
-sysfs_gpio = "0.5"
 serial-unix = "0.4.0"
 serial-core = "0.4.0"
 nb = "0.1.1"

src/lib.rs

@@ -19,6 +19,7 @@ pub extern crate nb;
 pub extern crate serial_core;
 pub extern crate serial_unix;
 pub extern crate spidev;
+#[cfg(feature = "gpio_sysfs")]
 pub extern crate sysfs_gpio;
 
 use std::io::{self, Write};
@@ -33,7 +34,13 @@ use spidev::SpidevTransfer;
 
 mod serial;
 
+#[cfg(feature = "gpio_sysfs")]
+/// Sysfs Pin wrapper module
+mod sysfs_pin;
+
 pub use serial::Serial;
+#[cfg(feature = "gpio_sysfs")]
+pub use sysfs_pin::SysfsPin;
 
 /// Empty struct that provides delay functionality on top of `thread::sleep`
 pub struct Delay;
@@ -92,72 +99,6 @@ impl hal::blocking::delay::DelayMs<u64> for Delay {
     }
 }
 
-/// Newtype around [`sysfs_gpio::Pin`] that implements the `embedded-hal` traits
-///
-/// [`sysfs_gpio::Pin`]: https://docs.rs/sysfs_gpio/0.5.1/sysfs_gpio/struct.Pin.html
-pub struct Pin(pub sysfs_gpio::Pin);
-
-impl Pin {
-    /// See [`sysfs_gpio::Pin::new`][0] for details.
-    ///
-    /// [0]: https://docs.rs/sysfs_gpio/0.5.1/sysfs_gpio/struct.Pin.html#method.new
-    pub fn new(pin_num: u64) -> Pin {
-        Pin(sysfs_gpio::Pin::new(pin_num))
-    }
-
-    /// See [`sysfs_gpio::Pin::from_path`][0] for details.
-    ///
-    /// [0]: https://docs.rs/sysfs_gpio/0.5.1/sysfs_gpio/struct.Pin.html#method.from_path
-    pub fn from_path<P>(path: P) -> sysfs_gpio::Result<Pin>
-    where
-        P: AsRef<Path>,
-    {
-        sysfs_gpio::Pin::from_path(path).map(Pin)
-    }
-}
-
-impl hal::digital::v2::OutputPin for Pin {
-    type Error = sysfs_gpio::Error;
-
-    fn set_low(&mut self) -> Result<(), Self::Error> {
-        self.0.set_value(0)
-    }
-
-    fn set_high(&mut self) -> Result<(), Self::Error> {
-        self.0.set_value(1)
-    }
-}
-
-impl hal::digital::v2::InputPin for Pin {
-    type Error = sysfs_gpio::Error;
-
-    fn is_high(&self) -> Result<bool, Self::Error> {
-        if !self.0.get_active_low()? {
-            self.0.get_value().map(|val| val != 0)
-        } else {
-            self.0.get_value().map(|val| val == 0)
-        }
-    }
-
-    fn is_low(&self) -> Result<bool, Self::Error> {
-        self.is_high().map(|val| !val)
-    }
-}
-
-impl ops::Deref for Pin {
-    type Target = sysfs_gpio::Pin;
-
-    fn deref(&self) -> &Self::Target {
-        &self.0
-    }
-}
-
-impl ops::DerefMut for Pin {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        &mut self.0
-    }
-}
-
 /// 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

src/sysfs_pin.rs

@@ -0,0 +1,68 @@
+use std::ops;
+use std::path::Path;
+
+/// Newtype around [`sysfs_gpio::Pin`] that implements the `embedded-hal` traits
+///
+/// [`sysfs_gpio::Pin`]: https://docs.rs/sysfs_gpio/0.5.1/sysfs_gpio/struct.Pin.html
+pub struct SysfsPin(pub sysfs_gpio::Pin);
+
+impl SysfsPin {
+    /// See [`sysfs_gpio::Pin::new`][0] for details.
+    ///
+    /// [0]: https://docs.rs/sysfs_gpio/0.5.1/sysfs_gpio/struct.Pin.html#method.new
+    pub fn new(pin_num: u64) -> Self {
+        SysfsPin(sysfs_gpio::Pin::new(pin_num))
+    }
+
+    /// See [`sysfs_gpio::Pin::from_path`][0] for details.
+    ///
+    /// [0]: https://docs.rs/sysfs_gpio/0.5.1/sysfs_gpio/struct.Pin.html#method.from_path
+    pub fn from_path<P>(path: P) -> sysfs_gpio::Result<Self>
+    where
+        P: AsRef<Path>,
+    {
+        sysfs_gpio::Pin::from_path(path).map(SysfsPin)
+    }
+}
+
+impl hal::digital::v2::OutputPin for SysfsPin {
+    type Error = sysfs_gpio::Error;
+
+    fn set_low(&mut self) -> Result<(), Self::Error> {
+        self.0.set_value(0)
+    }
+
+    fn set_high(&mut self) -> Result<(), Self::Error> {
+        self.0.set_value(1)
+    }
+}
+
+impl hal::digital::v2::InputPin for SysfsPin {
+    type Error = sysfs_gpio::Error;
+
+    fn is_high(&self) -> Result<bool, Self::Error> {
+        if !self.0.get_active_low()? {
+            self.0.get_value().map(|val| val != 0)
+        } else {
+            self.0.get_value().map(|val| val == 0)
+        }
+    }
+
+    fn is_low(&self) -> Result<bool, Self::Error> {
+        self.is_high().map(|val| !val)
+    }
+}
+
+impl ops::Deref for SysfsPin {
+    type Target = sysfs_gpio::Pin;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl ops::DerefMut for SysfsPin {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
+    }
+}