Backport fixing output pin behavior when active-low #61

Author: eldruin

CHANGELOG.md

@@ -18,6 +18,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Set default features to build both sysfs and cdev pin types
 - Removed `Pin` export, use `CdevPin` or `SysfsPin`
 
+### Fixed
+
+- Modified `OutputPin` behavior for active-low pins to match `InputPin` behavior.
+
 ## [v0.3.0] - 2019-11-25
 
 ### Added

src/cdev_pin.rs

@@ -19,11 +19,19 @@ impl hal::digital::v2::OutputPin for CdevPin {
     type Error = gpio_cdev::errors::Error;
 
     fn set_low(&mut self) -> Result<(), Self::Error> {
-        self.0.set_value(0)
+        if self.1 {
+            self.0.set_value(1)
+        } else {
+            self.0.set_value(0)
+        }
     }
 
     fn set_high(&mut self) -> Result<(), Self::Error> {
-        self.0.set_value(1)
+        if self.1 {
+            self.0.set_value(0)
+        } else {
+            self.0.set_value(1)
+        }
     }
 }
 

src/sysfs_pin.rs

@@ -30,11 +30,19 @@ 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)
+        if self.0.get_active_low()? {
+            self.0.set_value(1)
+        } else {
+            self.0.set_value(0)
+        }
     }
 
     fn set_high(&mut self) -> Result<(), Self::Error> {
-        self.0.set_value(1)
+        if self.0.get_active_low()? {
+            self.0.set_value(0)
+        } else {
+            self.0.set_value(1)
+        }
     }
 }