Remove free() from PeripheralMutex and all nrf drivers.

embassy-extras/src/peripheral.rs

@@ -1,30 +1,20 @@
 use core::cell::UnsafeCell;
 use core::marker::{PhantomData, PhantomPinned};
-use core::mem::MaybeUninit;
 use core::pin::Pin;
 use core::sync::atomic::{compiler_fence, Ordering};
 
 use embassy::interrupt::{Interrupt, InterruptExt};
 
-use crate::fmt::assert;
-
 pub trait PeripheralState {
     type Interrupt: Interrupt;
     fn on_interrupt(&mut self);
 }
 
-#[derive(Clone, Copy, PartialEq, Eq, Debug)]
-enum Life {
-    Ready,
-    Created,
-    Freed,
-}
-
 pub struct PeripheralMutex<S: PeripheralState> {
-    life: Life,
+    state: UnsafeCell<S>,
 
-    state: MaybeUninit<UnsafeCell<S>>, // Init if life != Freed
-    irq: MaybeUninit<S::Interrupt>,    // Init if life != Freed
+    irq_setup_done: bool,
+    irq: S::Interrupt,
 
     _not_send: PhantomData<*mut ()>,
     _pinned: PhantomPinned,
@@ -33,9 +23,10 @@ pub struct PeripheralMutex<S: PeripheralState> {
 impl<S: PeripheralState> PeripheralMutex<S> {
     pub fn new(state: S, irq: S::Interrupt) -> Self {
         Self {
-            life: Life::Created,
-            state: MaybeUninit::new(UnsafeCell::new(state)),
-            irq: MaybeUninit::new(irq),
+            irq,
+            irq_setup_done: false,
+
+            state: UnsafeCell::new(state),
             _not_send: PhantomData,
             _pinned: PhantomPinned,
         }
@@ -43,77 +34,49 @@ impl<S: PeripheralState> PeripheralMutex<S> {
 
     /// safety: self must be pinned.
     unsafe fn setup(&mut self) {
-        assert!(self.life == Life::Created);
-
-        let irq = &mut *self.irq.as_mut_ptr();
-        irq.disable();
+        self.irq.disable();
         compiler_fence(Ordering::SeqCst);
 
-        irq.set_handler(|p| {
+        self.irq.set_handler(|p| {
             // Safety: it's OK to get a &mut to the state, since
             // - We're in the IRQ, no one else can't preempt us
             // - We can't have preempted a with() call because the irq is disabled during it.
             let state = &mut *(p as *mut S);
             state.on_interrupt();
         });
-        irq.set_handler_context(self.state.as_mut_ptr() as *mut ());
+        self.irq
+            .set_handler_context((&mut self.state) as *mut _ as *mut ());
 
         compiler_fence(Ordering::SeqCst);
-        irq.enable();
+        self.irq.enable();
 
-        self.life = Life::Ready;
+        self.irq_setup_done = true;
     }
 
     pub fn with<R>(self: Pin<&mut Self>, f: impl FnOnce(&mut S, &mut S::Interrupt) -> R) -> R {
         let this = unsafe { self.get_unchecked_mut() };
-        if this.life != Life::Ready {
+        if !this.irq_setup_done {
             unsafe { this.setup() }
         }
 
-        let irq = unsafe { &mut *this.irq.as_mut_ptr() };
-
-        irq.disable();
+        this.irq.disable();
         compiler_fence(Ordering::SeqCst);
 
         // Safety: it's OK to get a &mut to the state, since the irq is disabled.
-        let state = unsafe { &mut *(*this.state.as_ptr()).get() };
+        let state = unsafe { &mut *this.state.get() };
 
-        let r = f(state, irq);
+        let r = f(state, &mut this.irq);
 
         compiler_fence(Ordering::SeqCst);
-        irq.enable();
+        this.irq.enable();
 
         r
     }
-
-    pub fn try_free(self: Pin<&mut Self>) -> Option<(S, S::Interrupt)> {
-        let this = unsafe { self.get_unchecked_mut() };
-
-        if this.life != Life::Freed {
-            return None;
-        }
-
-        unsafe { &mut *this.irq.as_mut_ptr() }.disable();
-        compiler_fence(Ordering::SeqCst);
-
-        this.life = Life::Freed;
-
-        let state = unsafe { this.state.as_ptr().read().into_inner() };
-        let irq = unsafe { this.irq.as_ptr().read() };
-        Some((state, irq))
-    }
-
-    pub fn free(self: Pin<&mut Self>) -> (S, S::Interrupt) {
-        unwrap!(self.try_free())
-    }
 }
 
 impl<S: PeripheralState> Drop for PeripheralMutex<S> {
     fn drop(&mut self) {
-        if self.life != Life::Freed {
-            let irq = unsafe { &mut *self.irq.as_mut_ptr() };
-            irq.disable();
-            irq.remove_handler();
-        }
+        self.irq.disable();
+        self.irq.remove_handler();
     }
 }