embedded_storage_async/
nor_flash.rs

1pub use embedded_storage::nor_flash::{ErrorType, NorFlashError, NorFlashErrorKind};
2
3/// Read only NOR flash trait.
4pub trait ReadNorFlash: ErrorType {
5	/// The minumum number of bytes the storage peripheral can read
6	const READ_SIZE: usize;
7
8	/// Read a slice of data from the storage peripheral, starting the read
9	/// operation at the given address offset, and reading `bytes.len()` bytes.
10	///
11	/// # Errors
12	///
13	/// Returns an error if the arguments are not aligned or out of bounds. The implementation
14	/// can use the [`check_read`] helper function.
15	async fn read(&mut self, offset: u32, bytes: &mut [u8]) -> Result<(), Self::Error>;
16
17	/// The capacity of the peripheral in bytes.
18	fn capacity(&self) -> usize;
19}
20
21/// NOR flash trait.
22pub trait NorFlash: ReadNorFlash {
23	/// The minumum number of bytes the storage peripheral can write
24	const WRITE_SIZE: usize;
25
26	/// The minumum number of bytes the storage peripheral can erase
27	const ERASE_SIZE: usize;
28
29	/// Erase the given storage range, clearing all data within `[from..to]`.
30	/// The given range will contain all 1s afterwards.
31	///
32	/// If power is lost during erase, contents of the page are undefined.
33	///
34	/// # Errors
35	///
36	/// Returns an error if the arguments are not aligned or out of bounds (the case where `to >
37	/// from` is considered out of bounds). The implementation can use the [`check_erase`]
38	/// helper function.
39	async fn erase(&mut self, from: u32, to: u32) -> Result<(), Self::Error>;
40
41	/// If power is lost during write, the contents of the written words are undefined,
42	/// but the rest of the page is guaranteed to be unchanged.
43	/// It is not allowed to write to the same word twice.
44	///
45	/// # Errors
46	///
47	/// Returns an error if the arguments are not aligned or out of bounds. The implementation
48	/// can use the [`check_write`] helper function.
49	async fn write(&mut self, offset: u32, bytes: &[u8]) -> Result<(), Self::Error>;
50}
51
52impl<T: ReadNorFlash> ReadNorFlash for &mut T {
53	const READ_SIZE: usize = T::READ_SIZE;
54
55	async fn read(&mut self, offset: u32, bytes: &mut [u8]) -> Result<(), Self::Error> {
56		T::read(self, offset, bytes).await
57	}
58
59	fn capacity(&self) -> usize {
60		T::capacity(self)
61	}
62}
63
64impl<T: NorFlash> NorFlash for &mut T {
65	const WRITE_SIZE: usize = T::WRITE_SIZE;
66	const ERASE_SIZE: usize = T::ERASE_SIZE;
67
68	async fn erase(&mut self, from: u32, to: u32) -> Result<(), Self::Error> {
69		T::erase(self, from, to).await
70	}
71
72	async fn write(&mut self, offset: u32, bytes: &[u8]) -> Result<(), Self::Error> {
73		T::write(self, offset, bytes).await
74	}
75}
76
77/// Marker trait for NorFlash relaxing the restrictions on `write`.
78///
79/// Writes to the same word twice are now allowed. The result is the logical AND of the
80/// previous data and the written data. That is, it is only possible to change 1 bits to 0 bits.
81///
82/// If power is lost during write:
83/// - Bits that were 1 on flash and are written to 1 are guaranteed to stay as 1
84/// - Bits that were 1 on flash and are written to 0 are undefined
85/// - Bits that were 0 on flash are guaranteed to stay as 0
86/// - Rest of the bits in the page are guaranteed to be unchanged
87pub trait MultiwriteNorFlash: NorFlash {}
embedded_storage_async/nor_flash.rs

embedded_storage_async/
nor_flash.rs
