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E.g. >> >> bitfield! { >> pub struct Foo(u32) { >> ... >> } >> } >> >> #[repr(C)] >> struct Bar { >> foo: Foo, >> } >> >> let mmio: Mmio<'_, Bar> =3D ...; >> io_read!(mmio, .foo) >> >> Currently this feature is available from `register!()` macro but not >> otherwise available with `io_read!`, `io_write!`. Support this by >> performing conversions to I/O primitives via the `AsRepr`/`AsReprMut` >> trait. >> >> This makes the `IoLoc::IoType` and `Register::Storage` redundant; thus >> remove them; also convert register methods to use the `read_val` and >> `write_val` instead. > > Nice, the redundancy was bothering me a bit so this is clearly a better > design. > > Reviewed-by: Alexandre Courbot > >> >> Signed-off-by: Gary Guo >> --- >> rust/kernel/bitfield.rs | 10 ++++ >> rust/kernel/io.rs | 135 +++++++++++++++++++++++++-------------= ------- >> rust/kernel/io/register.rs | 15 ----- >> rust/macros/io/register.rs | 2 - >> 4 files changed, 86 insertions(+), 76 deletions(-) >> >> diff --git a/rust/kernel/bitfield.rs b/rust/kernel/bitfield.rs >> index a0d089423f21..619c5e2189d1 100644 >> --- a/rust/kernel/bitfield.rs >> +++ b/rust/kernel/bitfield.rs >> @@ -308,6 +308,7 @@ macro_rules! bitfield { >> $(#[$attr])* >> #[repr(transparent)] >> #[derive(Clone, Copy, PartialEq, Eq)] >> + #[derive($crate::prelude::FromBytes, $crate::prelude::IntoBytes= )] > > Do we need `FromBytes`/`IntoBytes` for every single bitfield type? I > mean that probably doesn't hurt, but if we need them for registers then > we can derive them from the register macro. These are not needed now (as `AsRepr` provides sufficient guarantee so read_val/write_val use unsafe with them instead); but I kept them as I thin= k it's useful derive regardless. I suppose these are not needed for `register= !` so direct user of `bitfield` can derive them manually instead. Best, Gary