device-driver 2.0.0

A toolkit to write better device drivers, faster
Documentation 
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use device_driver::{FieldsetMetadata, RegisterInterface, RegisterInterfaceBase};

pub struct DeviceInterface;

impl RegisterInterfaceBase for DeviceInterface {
    type Error = ();
    type AddressType = u8;
}
impl RegisterInterface for DeviceInterface {
    fn write_register(
        &mut self,
        _address: Self::AddressType,
        data: &mut [u8],
        _metadata: &FieldsetMetadata,
    ) -> Result<(), Self::Error> {
        // Assert data is little endian
        assert_eq!(data, &[0x34, 0x12]);

        Ok(())
    }

    fn read_register(
        &mut self,
        _address: Self::AddressType,
        data: &mut [u8],
        _metadata: &FieldsetMetadata,
    ) -> Result<(), Self::Error> {
        data.copy_from_slice(&[0x32, 0x12]);
        Ok(())
    }
}

device_driver::compile!(
    unstable_ddsl: "
        device MyTestDevice {
            register-address-type: u8,
            default-access: RW,

            register FooLE {
                address-overlap: allow,
                address: 0,
                reset: 0x1234,

                fields: fieldset FooLEFields {
                    byte-order: LE,
                    size-bytes: 2,

                    field val 15:0 -> uint
                }
            },
            register FooLEArray {
                address-overlap: allow,
                address: 0,
                reset: [0x34, 0x12],

                fields: fieldset FooLEArrayFields {
                    byte-order: LE,
                    size-bytes: 2,

                    field val 15:0 -> uint
                }
            },
            register FooBE {
                address-overlap: allow,
                address: 0,
                reset: 0x3412,

                fields: fieldset FooBEFields {
                    byte-order: BE,
                    size-bytes: 2,

                    field val 15:0 -> uint
                }
            },
            register FooBEArray {
                address-overlap: allow,
                address: 0,
                reset: [0x34, 0x12],

                fields: fieldset FooBEArrayFields {
                    byte-order: BE,
                    size-bytes: 2,

                    field val 15:0 -> uint
                }
            }
        }
    "
);

#[test]
fn little_endian_respected() {
    let mut device = MyTestDevice::new(DeviceInterface);

    device.foo_le().write(|_| {}).unwrap();
    device
        .foo_le()
        .write_with_zero(|reg| reg.set_val(0x1234))
        .unwrap();

    device.foo_le_array().write(|_| {}).unwrap();
    device
        .foo_le_array()
        .write_with_zero(|reg| reg.set_val(0x1234))
        .unwrap();
}

#[test]
fn big_endian_respected() {
    let mut device = MyTestDevice::new(DeviceInterface);

    device.foo_be().write(|_| {}).unwrap();
    device
        .foo_be()
        .write_with_zero(|reg| reg.set_val(0x3412))
        .unwrap();

    device.foo_be_array().write(|_| {}).unwrap();
    device
        .foo_be_array()
        .write_with_zero(|reg| reg.set_val(0x3412))
        .unwrap();
}