Reworked PWR to use a constrain trait.

Author: MabezDev

examples/rtc.rs

@@ -19,7 +19,6 @@ use hal::stm32l4::stm32l4x2;
 
 use hal::delay::Delay;
 use hal::rtc::Rtc;
-use hal::pwr::Pwr;
 use hal::datetime::{Date,Time};
 use rt::ExceptionFrame;
 
@@ -42,12 +41,9 @@ fn main() -> ! {
 
     // Try a different clock configuration
     let clocks = rcc.cfgr.freeze(&mut flash.acr);
-    // let clocks = rcc.cfgr
-    //     .sysclk(64.mhz())
-    //     .pclk1(32.mhz())
-    //     .freeze(&mut flash.acr);
+    
     let mut timer = Delay::new(cp.SYST, clocks);
-    let mut pwr = Pwr::pwr(&mut rcc.apb1r1);
+    let mut pwr = dp.PWR.constrain(&mut rcc.apb1r1);
     let rtc = Rtc::rtc(dp.RTC, &mut rcc.apb1r1, &mut rcc.bdcr, &mut pwr.cr1);
 
     let mut time = Time::new(21.hours(), 57.minutes(), 32.seconds(), false);
@@ -64,6 +60,8 @@ fn main() -> ! {
     date = rtc.get_date();
 
 
+    writeln!(hstdout, "Time: {:?}", time).unwrap();
+    writeln!(hstdout, "Date: {:?}", date).unwrap();
     writeln!(hstdout, "Good bye!").unwrap();
     loop {}
 }

src/prelude.rs

@@ -6,4 +6,5 @@ pub use gpio::GpioExt as _GpioExtHal;
 pub use hal::prelude::*; // embedded hal traits
 pub use time::U32Ext as _stm32f30x_hal_time_U32Ext;
 pub use datetime::U32Ext as _stm32f30x_hal_datetime;
-pub use dma::DmaExt as _DmaExtHal;
+pub use dma::DmaExt as _DmaExtHal;
+pub use pwr::PwrExt as _PwrExtHal;

src/pwr.rs

@@ -1,6 +1,3 @@
-// TODO impl power module so we enable backup domain for rtc etc
-// apb1r1.enr().modify(|_, w| w.pwren().set_bit());
-
 use rcc::{APB1R1};
 use stm32l4::stm32l4x2::{pwr, PWR};
 
@@ -12,11 +9,17 @@ pub struct Pwr {
     pub cr4: CR4,
 }
 
-impl Pwr {
-    pub fn pwr(apb1r1: &mut APB1R1) -> Self {
-        apb1r1.enr().modify(|_, w| w.pwren().set_bit());
+/// Extension trait that constrains the `PWR` peripheral
+pub trait PwrExt {
+    /// Constrains the `PWR` peripheral so it plays nicely with the other abstractions
+    fn constrain(self, &mut APB1R1) -> Pwr;
+}
 
-        Self {
+impl PwrExt for PWR {
+    fn constrain(self, apb1r1: &mut APB1R1) -> Pwr {
+        // Enable the peripheral clock
+        apb1r1.enr().modify(|_, w| w.pwren().set_bit());
+        Pwr {
             cr1: CR1 { _0: () },
             cr2: CR2 { _0: () },
             cr3: CR3 { _0: () },