sdmmc-core 0.5.0

SD/MMC core data structures and algorithms
Documentation
use crate::lib_bitfield;
use crate::result::{Error, Result};

mod vhs;

pub use vhs::*;

lib_bitfield! {
    /// Argumentument for CMD8.
    pub Argument(u32): u8 {
        /// Programs the supply voltage of the card.
        raw_vhs: 11, 8;
        /// Programs the check pattern of the card.
        raw_check_pattern: 7, 0;
    }
}

impl Argument {
    /// Represents the byte length of the [Argument].
    pub const LEN: usize = 4;
    /// Represents the default value of the [Argument].
    pub const DEFAULT: u32 = 0x0100;

    /// Creates a new [Argument].
    pub const fn new() -> Self {
        Self(Self::DEFAULT)
    }

    /// Gets the `Voltage Host Supplied` field of the [Argument].
    pub const fn vhs(&self) -> Result<VoltageSupplied> {
        VoltageSupplied::from_raw(self.raw_vhs())
    }

    /// Sets the `Voltage Host Supplied` field of the [Argument].
    pub fn set_vhs(&mut self, val: VoltageSupplied) {
        self.set_raw_vhs(val.into_raw() as u32);
    }

    /// Gets the check pattern field of the [Argument].
    pub const fn check_pattern(&self) -> u8 {
        self.raw_check_pattern()
    }

    /// Sets the check pattern field of the [Argument].
    pub fn set_check_pattern(&mut self, val: u8) {
        self.set_raw_check_pattern(val as u32);
    }

    /// Attempts to convert a [`u32`] into an [Argument].
    pub const fn try_from_bits(val: u32) -> Result<Self> {
        match Self(val) {
            arg if arg.vhs().is_err() => Err(Error::invalid_field_variant(
                "cmd::argument::vhs",
                arg.raw_vhs() as usize,
            )),
            arg => Ok(arg),
        }
    }

    /// Converts the [Argument] into a byte array.
    pub const fn bytes(&self) -> [u8; Self::LEN] {
        self.0.to_be_bytes()
    }

    /// Attempts to convert a byte slice into an [Argument].
    pub const fn try_from_bytes(val: &[u8]) -> Result<Self> {
        match val.len() {
            len if len < Self::LEN => Err(Error::invalid_length(len, Self::LEN)),
            _ => Self::try_from_bits(u32::from_be_bytes([val[0], val[1], val[2], val[3]])),
        }
    }
}

impl Default for Argument {
    fn default() -> Self {
        Self::new()
    }
}

impl From<Argument> for u32 {
    fn from(val: Argument) -> Self {
        val.bits()
    }
}

impl From<Argument> for [u8; Argument::LEN] {
    fn from(val: Argument) -> Self {
        val.bytes()
    }
}

impl TryFrom<u32> for Argument {
    type Error = Error;

    fn try_from(val: u32) -> Result<Argument> {
        Argument::try_from_bits(val)
    }
}

impl TryFrom<&[u8]> for Argument {
    type Error = Error;

    fn try_from(val: &[u8]) -> Result<Argument> {
        Argument::try_from_bytes(val)
    }
}

impl<const N: usize> TryFrom<&[u8; N]> for Argument {
    type Error = Error;

    fn try_from(val: &[u8; N]) -> Result<Argument> {
        Argument::try_from_bytes(val.as_ref())
    }
}

impl<const N: usize> TryFrom<[u8; N]> for Argument {
    type Error = Error;

    fn try_from(val: [u8; N]) -> Result<Argument> {
        Argument::try_from_bytes(val.as_ref())
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_fields() {
        let arg = Argument::new();
        let new_vhs = VoltageSupplied::new();

        assert_eq!(arg.vhs(), Ok(new_vhs));
        assert_eq!(arg.check_pattern(), 0);

        (1..=12).map(|r| (1u32 << r) - 1).for_each(|raw_arg| {
            let raw = raw_arg.to_be_bytes();
            let raw_vhs = (raw_arg >> 8) as u8;
            let exp_check = (raw_arg & 0xff) as u8;

            match VoltageSupplied::from_raw(raw_vhs) {
                Ok(exp_vhs) => {
                    let mut exp_arg = Argument(raw_arg);

                    assert_eq!(Argument::try_from_bits(raw_arg), Ok(exp_arg));
                    assert_eq!(Argument::try_from_bytes(&raw), Ok(exp_arg));
                    assert_eq!(Argument::try_from(&raw), Ok(exp_arg));
                    assert_eq!(Argument::try_from(raw), Ok(exp_arg));

                    assert_eq!(exp_arg.vhs(), Ok(exp_vhs));

                    exp_arg.set_vhs(new_vhs);
                    assert_eq!(exp_arg.vhs(), Ok(new_vhs));

                    exp_arg.set_vhs(exp_vhs);
                    assert_eq!(exp_arg.vhs(), Ok(exp_vhs));

                    assert_eq!(exp_arg.check_pattern(), exp_check);

                    exp_arg.set_check_pattern(0);
                    assert_eq!(exp_arg.check_pattern(), 0);

                    exp_arg.set_check_pattern(exp_check);
                    assert_eq!(exp_arg.check_pattern(), exp_check);

                    assert_eq!(exp_arg.bits(), raw_arg);
                    assert_eq!(exp_arg.bytes(), raw);
                }
                Err(_) => {
                    let exp_err =
                        Error::invalid_field_variant("cmd::argument::vhs", raw_vhs as usize);

                    assert_eq!(Argument::try_from_bits(raw_arg), Err(exp_err));
                    assert_eq!(Argument::try_from_bytes(&raw), Err(exp_err));
                    assert_eq!(Argument::try_from(&raw), Err(exp_err));
                    assert_eq!(Argument::try_from(raw), Err(exp_err));
                }
            }
        });
    }
}