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Struct embassy_rp::PeripheralRef

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pub struct PeripheralRef<'a, T> { /* private fields */ }
Expand description

An exclusive reference to a peripheral.

This is functionally the same as a &'a mut T. There’s a few advantages in having a dedicated struct instead:

  • Memory efficiency: Peripheral singletons are typically either zero-sized (for concrete peripherals like PA9 or SPI4) or very small (for example AnyPin, which is 1 byte). However &mut T is always 4 bytes for 32-bit targets, even if T is zero-sized. PeripheralRef stores a copy of T instead, so it’s the same size.
  • Code size efficiency. If the user uses the same driver with both SPI4 and &mut SPI4, the driver code would be monomorphized two times. With PeripheralRef, the driver is generic over a lifetime only. SPI4 becomes PeripheralRef<'static, SPI4>, and &mut SPI4 becomes PeripheralRef<'a, SPI4>. Lifetimes don’t cause monomorphization.

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impl<'a, T> PeripheralRef<'a, T>

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pub fn new(inner: T) -> PeripheralRef<'a, T>

Create a new reference to a peripheral.

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pub unsafe fn clone_unchecked(&self) -> PeripheralRef<'a, T>
where T: Peripheral<P = T>,

Unsafely clone (duplicate) a peripheral singleton.

Safety

This returns an owned clone of the peripheral. You must manually ensure only one copy of the peripheral is in use at a time. For example, don’t create two SPI drivers on SPI1, because they will “fight” each other.

You should strongly prefer using reborrow() instead. It returns a PeripheralRef that borrows self, which allows the borrow checker to enforce this at compile time.

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pub fn reborrow(&mut self) -> PeripheralRef<'_, T>
where T: Peripheral<P = T>,

Reborrow into a “child” PeripheralRef.

self will stay borrowed until the child PeripheralRef is dropped.

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pub fn map_into<U>(self) -> PeripheralRef<'a, U>
where T: Into<U>,

Map the inner peripheral using Into.

This converts from PeripheralRef<'a, T> to PeripheralRef<'a, U>, using an Into impl to convert from T to U.

For example, this can be useful to degrade GPIO pins: converting from PeripheralRef<’a, PB11>toPeripheralRef<’a, AnyPin>`.

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impl<'a, T> Deref for PeripheralRef<'a, T>

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type Target = T

The resulting type after dereferencing.
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fn deref(&self) -> &<PeripheralRef<'a, T> as Deref>::Target

Dereferences the value.

Auto Trait Implementations§

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impl<'a, T> RefUnwindSafe for PeripheralRef<'a, T>
where T: RefUnwindSafe,

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impl<'a, T> Send for PeripheralRef<'a, T>
where T: Send,

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impl<'a, T> Sync for PeripheralRef<'a, T>
where T: Sync,

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impl<'a, T> Unpin for PeripheralRef<'a, T>
where T: Unpin,

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impl<'a, T> !UnwindSafe for PeripheralRef<'a, T>

Blanket Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Az for T

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fn az<Dst>(self) -> Dst
where T: Cast<Dst>,

Casts the value.
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<Src, Dst> CastFrom<Src> for Dst
where Src: Cast<Dst>,

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fn cast_from(src: Src) -> Dst

Casts the value.
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impl<T> CheckedAs for T

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fn checked_as<Dst>(self) -> Option<Dst>
where T: CheckedCast<Dst>,

Casts the value.
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impl<Src, Dst> CheckedCastFrom<Src> for Dst
where Src: CheckedCast<Dst>,

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fn checked_cast_from(src: Src) -> Option<Dst>

Casts the value.
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<Src, Dst> LosslessTryInto<Dst> for Src
where Dst: LosslessTryFrom<Src>,

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fn lossless_try_into(self) -> Option<Dst>

Performs the conversion.
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impl<Src, Dst> LossyInto<Dst> for Src
where Dst: LossyFrom<Src>,

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fn lossy_into(self) -> Dst

Performs the conversion.
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impl<T> OverflowingAs for T

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fn overflowing_as<Dst>(self) -> (Dst, bool)
where T: OverflowingCast<Dst>,

Casts the value.
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impl<Src, Dst> OverflowingCastFrom<Src> for Dst
where Src: OverflowingCast<Dst>,

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fn overflowing_cast_from(src: Src) -> (Dst, bool)

Casts the value.
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impl<'b, T> Peripheral for T
where T: Deref, <T as Deref>::Target: Peripheral,

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type P = <<T as Deref>::Target as Peripheral>::P

Peripheral singleton type
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unsafe fn clone_unchecked(&self) -> <T as Peripheral>::P

Unsafely clone (duplicate) a peripheral singleton. Read more
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fn into_ref<'a>(self) -> PeripheralRef<'a, Self::P>
where Self: 'a,

Convert a value into a PeripheralRef. Read more
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impl<T> Same for T

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type Output = T

Should always be Self
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impl<T> SaturatingAs for T

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fn saturating_as<Dst>(self) -> Dst
where T: SaturatingCast<Dst>,

Casts the value.
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impl<Src, Dst> SaturatingCastFrom<Src> for Dst
where Src: SaturatingCast<Dst>,

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fn saturating_cast_from(src: Src) -> Dst

Casts the value.
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
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impl<T> UnwrappedAs for T

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fn unwrapped_as<Dst>(self) -> Dst
where T: UnwrappedCast<Dst>,

Casts the value.
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impl<Src, Dst> UnwrappedCastFrom<Src> for Dst
where Src: UnwrappedCast<Dst>,

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fn unwrapped_cast_from(src: Src) -> Dst

Casts the value.
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impl<T> WrappingAs for T

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fn wrapping_as<Dst>(self) -> Dst
where T: WrappingCast<Dst>,

Casts the value.
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impl<Src, Dst> WrappingCastFrom<Src> for Dst
where Src: WrappingCast<Dst>,

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fn wrapping_cast_from(src: Src) -> Dst

Casts the value.