Replace void with Infallible (#100)

Author: burrbull

CHANGELOG.md

@@ -16,6 +16,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Breaking changes
 
+- `void::Void` replaced with `Infallible` where it is possible
 - Change timer/pwm init API
 - Remove `set_low` and `set_high` for pins in Alternate output mode
 - Renames `set_seconds` and `seconds` methods on RTC to `set_time` and `current_time`, respectively

README.md

@@ -110,14 +110,15 @@ fn main() -> ! {
     // in order to configure the port. For pins 0-7, crl should be passed instead.
     let mut led = gpioc.pc13.into_push_pull_output(&mut gpioc.crh);
     // Configure the syst timer to trigger an update every second
-    let mut timer = Timer::syst(cp.SYST, 1.hz(), clocks);
+    let mut timer = Timer::syst(cp.SYST, clocks)
+        .start_count_down(1.hz());
 
     // Wait for the timer to trigger an update and change the state of the LED
     loop {
         block!(timer.wait()).unwrap();
-        led.set_high();
+        led.set_high().unwrap();
         block!(timer.wait()).unwrap();
-        led.set_low();
+        led.set_low().unwrap();
     }
 }
 ```

src/gpio.rs

@@ -77,7 +77,7 @@ macro_rules! gpio {
     ]) => {
         /// GPIO
         pub mod $gpiox {
-            use void::Void;
+            use core::convert::Infallible;
             use core::marker::PhantomData;
 
             use crate::hal::digital::v2::{InputPin, OutputPin, StatefulOutputPin, toggleable};
@@ -164,7 +164,7 @@ macro_rules! gpio {
             }
 
             impl<MODE> OutputPin for Generic<Output<MODE>> {
-                type Error = Void;
+                type Error = Infallible;
                 fn set_high(&mut self) -> Result<(), Self::Error> {
                     // NOTE(unsafe) atomic write to a stateless register
                     Ok(unsafe { (*$GPIOX::ptr()).bsrr.write(|w| w.bits(1 << self.i)) })
@@ -177,7 +177,7 @@ macro_rules! gpio {
             }
 
             impl<MODE> InputPin for Generic<Input<MODE>> {
-                type Error = Void;
+                type Error = Infallible;
                 fn is_high(&self) -> Result<bool, Self::Error> {
                     self.is_low().map(|b| !b)
                 }
@@ -202,7 +202,7 @@ macro_rules! gpio {
             impl <MODE> toggleable::Default for Generic<Output<MODE>> {}
 
             impl InputPin for Generic<Output<OpenDrain>> {
-                type Error = Void;
+                type Error = Infallible;
                 fn is_high(&self) -> Result<bool, Self::Error> {
                     self.is_low().map(|b| !b)
                 }
@@ -470,7 +470,7 @@ macro_rules! gpio {
                 }
 
                 impl<MODE> OutputPin for $PXi<Output<MODE>> {
-                    type Error = Void;
+                    type Error = Infallible;
                     fn set_high(&mut self) -> Result<(), Self::Error> {
                         // NOTE(unsafe) atomic write to a stateless register
                         Ok(unsafe { (*$GPIOX::ptr()).bsrr.write(|w| w.bits(1 << $i)) })
@@ -496,7 +496,7 @@ macro_rules! gpio {
                 impl<MODE> toggleable::Default for $PXi<Output<MODE>> {}
 
                 impl<MODE> InputPin for $PXi<Input<MODE>> {
-                    type Error = Void;
+                    type Error = Infallible;
                     fn is_high(&self) -> Result<bool, Self::Error> {
                         self.is_low().map(|b| !b)
                     }
@@ -508,7 +508,7 @@ macro_rules! gpio {
                 }
 
                 impl InputPin for $PXi<Output<OpenDrain>> {
-                    type Error = Void;
+                    type Error = Infallible;
                     fn is_high(&self) -> Result<bool, Self::Error> {
                         self.is_low().map(|b| !b)
                     }
@@ -525,8 +525,8 @@ macro_rules! gpio {
 
 macro_rules! impl_pxx {
     ($(($port:ident :: $pin:ident)),*) => {
-        use void::Void;
         use embedded_hal::digital::v2::{InputPin, StatefulOutputPin, OutputPin};
+        use core::convert::Infallible;
 
         pub enum Pxx<MODE> {
             $(
@@ -535,14 +535,14 @@ macro_rules! impl_pxx {
         }
 
         impl<MODE> OutputPin for Pxx<Output<MODE>> {
-            type Error = Void;
-            fn set_high(&mut self) -> Result<(), Void> {
+            type Error = Infallible;
+            fn set_high(&mut self) -> Result<(), Infallible> {
                 match self {
                     $(Pxx::$pin(pin) => pin.set_high()),*
                 }
             }
 
-            fn set_low(&mut self) -> Result<(), Void> {
+            fn set_low(&mut self) -> Result<(), Infallible> {
                 match self {
                     $(Pxx::$pin(pin) => pin.set_low()),*
                 }
@@ -564,14 +564,14 @@ macro_rules! impl_pxx {
         }
 
         impl<MODE> InputPin for Pxx<Input<MODE>> {
-            type Error = Void;
-            fn is_high(&self) -> Result<bool, Void> {
+            type Error = Infallible;
+            fn is_high(&self) -> Result<bool, Infallible> {
                 match self {
                     $(Pxx::$pin(pin) => pin.is_high()),*
                 }
             }
 
-            fn is_low(&self) -> Result<bool, Void> {
+            fn is_low(&self) -> Result<bool, Infallible> {
                 match self {
                     $(Pxx::$pin(pin) => pin.is_low()),*
                 }

src/rtc.rs

@@ -18,7 +18,7 @@ use crate::backup_domain::BackupDomain;
 use crate::time::Hertz;
 
 use nb;
-use void::Void;
+use core::convert::Infallible;
 
 // The LSE runs at at 32 768 hertz unless an external clock is provided
 const LSE_HERTZ: u32 = 32_768;
@@ -170,11 +170,11 @@ impl Rtc {
       use nb::block;
 
       rtc.set_alarm(rtc.read_counts() + 5);
-      // NOTE: Safe unwrap because Void can't be returned
+      // NOTE: Safe unwrap because Infallible can't be returned
       block!(rtc.wait_alarm()).unwrap();
       ```
     */
-    pub fn wait_alarm(&mut self) -> nb::Result<(), Void> {
+    pub fn wait_alarm(&mut self) -> nb::Result<(), Infallible> {
         if self.regs.crl.read().alrf().bit() == true {
             self.regs.crl.modify(|_, w| w.alrf().clear_bit());
             Ok(())

src/serial.rs

@@ -42,7 +42,7 @@ use core::sync::atomic::{self, Ordering};
 
 use nb;
 use crate::pac::{USART1, USART2, USART3};
-use void::Void;
+use core::convert::Infallible;
 use embedded_hal::serial::Write;
 
 use crate::afio::MAPR;
@@ -388,7 +388,7 @@ macro_rules! hal {
             }
 
             impl crate::hal::serial::Write<u8> for Tx<$USARTX> {
-                type Error = Void;
+                type Error = Infallible;
 
                 fn flush(&mut self) -> nb::Result<(), Self::Error> {
                     // NOTE(unsafe) atomic read with no side effects