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//! Delays
//!
//! # What's the difference between these traits and the `timer::CountDown` trait?
//!
//! The `Timer` trait provides a *non-blocking* timer abstraction and it's meant to be used to build
//! higher level abstractions like I/O operations with timeouts. OTOH, these delays traits only
//! provide *blocking* functionality. Note that you can also use the `timer::CountDown` trait to
//! implement blocking delays.

/// Blocking delay traits
pub mod blocking {
    /// Microsecond delay
    ///
    pub trait DelayUs {
        /// Enumeration of `DelayUs` errors
        type Error: core::fmt::Debug;

        /// Pauses execution for at minimum `us` microseconds. Pause can be longer
        /// if the implementation requires it due to precision/timing issues.
        fn delay_us(&mut self, us: u32) -> Result<(), Self::Error>;

        /// Pauses execution for at minimum `ms` milliseconds. Pause can be longer
        /// if the implementation requires it due to precision/timing issues.
        fn delay_ms(&mut self, ms: u32) -> Result<(), Self::Error> {
            for _ in 0..ms {
                self.delay_us(1000)?;
            }

            Ok(())
        }
    }

    impl<T> DelayUs for &mut T
    where
        T: DelayUs,
    {
        type Error = T::Error;

        fn delay_us(&mut self, us: u32) -> Result<(), Self::Error> {
            T::delay_us(self, us)
        }

        fn delay_ms(&mut self, ms: u32) -> Result<(), Self::Error> {
            T::delay_ms(self, ms)
        }
    }
}