embedded 0.2.0

Work in progress embedded library; pre-release for single issue.
Documentation 
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//! Undocumented prerelease of volatile module.
//!
//! When using, please pin to version 0.2.

use core::{ops, ptr};

#[repr(C)]
pub struct Volatile<T>(T);

impl<T> Volatile<T> {
    #[inline(always)]
    pub fn read(&self) -> T {
        unsafe {
            ptr::read_volatile(&self.0 as *const T)
        }
    }

    #[inline(always)]
    pub fn write(&mut self, src: T) {
        unsafe {
            ptr::write_volatile(&mut self.0, src)
        }
    }
}

impl<T> ops::BitOrAssign<T> for Volatile<T>
where T: ops::BitOr<T, Output=T>
{
    #[inline(always)]
    fn bitor_assign(&mut self, val: T) {
        let tmp = self.read();
        let new_val = tmp | val;
        self.write(new_val);
    }
}

pub trait VolatileStruct : Sized {
    #[inline(always)]
    unsafe fn from_ptr(addr: *mut Self) -> &'static mut Self {
        let item: &'static mut Self = &mut *addr;
        item
    }

    #[inline(always)]
    unsafe fn from_addr(addr: usize) -> &'static mut Self {
        // we need the Sized trait here, otherwise the cast doesn't work
        Self::from_ptr(addr as *mut Self)
    }
}