rpi_embedded 0.1.0

// Copyright (c) 2017-2019 Rene van der Meer
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.

use embedded_hal::blocking::spi::{Transfer, Write};
use embedded_hal::spi::FullDuplex;
use nb;

use super::{Error, Result, Spi};

impl Transfer<u8> for Spi {
    type Error = Error;

    fn transfer<'a>(&mut self, buffer: &'a mut [u8]) -> Result<&'a [u8]> {
        let write_buffer = buffer.to_vec();
        Spi::transfer(self, buffer, &write_buffer)?;

        Ok(buffer)
    }
}

impl Write<u8> for Spi {
    type Error = Error;

    fn write(&mut self, buffer: &[u8]) -> Result<()> {
        Spi::write(self, buffer)?;

        Ok(())
    }
}

impl FullDuplex<u8> for Spi {
    type Error = Error;

    fn read(&mut self) -> nb::Result<u8, Self::Error> {
        Ok(self.last_read)
    }

    fn send(&mut self, byte: u8) -> nb::Result<(), Self::Error> {
        let mut read_buffer: [u8; 1] = [0];

        Spi::transfer(self, &mut read_buffer, &[byte])?;
        self.last_read = read_buffer[0];

        Ok(())
    }
}