Trait embassy_stm32::Peripheral
source · pub trait Peripheral: Sized {
type P;
// Required method
unsafe fn clone_unchecked(&self) -> Self::P;
// Provided method
fn into_ref<'a>(self) -> PeripheralRef<'a, Self::P>
where Self: 'a { ... }
}
Expand description
Trait for any type that can be used as a peripheral of type P
.
This is used in driver constructors, to allow passing either owned peripherals (e.g. TWISPI0
),
or borrowed peripherals (e.g. &mut TWISPI0
).
For example, if you have a driver with a constructor like this:
impl<'d, T: Instance> Twim<'d, T> {
pub fn new(
twim: impl Peripheral<P = T> + 'd,
irq: impl Peripheral<P = T::Interrupt> + 'd,
sda: impl Peripheral<P = impl GpioPin> + 'd,
scl: impl Peripheral<P = impl GpioPin> + 'd,
config: Config,
) -> Self { .. }
}
You may call it with owned peripherals, which yields an instance that can live forever ('static
):
let mut twi: Twim<'static, ...> = Twim::new(p.TWISPI0, irq, p.P0_03, p.P0_04, config);
Or you may call it with borrowed peripherals, which yields an instance that can only live for as long as the borrows last:
let mut twi: Twim<'_, ...> = Twim::new(&mut p.TWISPI0, &mut irq, &mut p.P0_03, &mut p.P0_04, config);
§Implementation details, for HAL authors
When writing a HAL, the intended way to use this trait is to take impl Peripheral<P = ..>
in
the HAL’s public API (such as driver constructors), calling .into_ref()
to obtain a PeripheralRef
,
and storing that in the driver struct.
.into_ref()
on an owned T
yields a PeripheralRef<'static, T>
.
.into_ref()
on an &'a mut T
yields a PeripheralRef<'a, T>
.
Required Associated Types§
Required Methods§
sourceunsafe fn clone_unchecked(&self) -> Self::P
unsafe fn clone_unchecked(&self) -> Self::P
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 into_ref()
instead. It returns a
PeripheralRef
, which allows the borrow checker to enforce this at compile time.
Provided Methods§
sourcefn into_ref<'a>(self) -> PeripheralRef<'a, Self::P>where
Self: 'a,
fn into_ref<'a>(self) -> PeripheralRef<'a, Self::P>where
Self: 'a,
Convert a value into a PeripheralRef
.
When called on an owned T
, yields a PeripheralRef<'static, T>
.
When called on an &'a mut T
, yields a PeripheralRef<'a, T>
.