Merge #722

722: FieldSpec r=Emilgardis a=burrbull



Co-authored-by: Andrey Zgarbul <zgarbul.andrey@gmail.com>

Author: bors[bot]

CHANGELOG.md

@@ -7,6 +7,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/).
 
 ## [Unreleased]
 
+- `FieldFpec` instead or `fty` generic
 - removed `rty` generic in `FieldWriter`
 - `bool` and `u8` as default generics for `BitReader/Writer` and `FieldReader/Writer`
 - Bump MSRV to 1.65

src/generate/generic.rs

@@ -33,6 +33,9 @@ macro_rules! raw_reg {
         const fn $mask<const WI: u8>() -> $U {
             <$U>::MAX >> ($size - WI)
         }
+        impl FieldSpec for $U {
+            type Ux = $U;
+        }
     };
 }
 
@@ -47,6 +50,12 @@ pub trait RegisterSpec {
     type Ux: RawReg;
 }
 
+/// Raw field type
+pub trait FieldSpec: Sized {
+    /// Raw field type (`u8`, `u16`, `u32`, ...).
+    type Ux: Copy + PartialEq + From<Self>;
+}
+
 /// Trait implemented by readable registers to enable the `read` method.
 ///
 /// Registers marked with `Writable` can be also be `modify`'ed.
@@ -301,19 +310,19 @@ impl<REG: RegisterSpec> W<REG> {
 }
 
 #[doc(hidden)]
-pub struct FieldReaderRaw<U, FI> {
-    pub(crate) bits: U,
+pub struct FieldReaderRaw<FI = u8>
+where
+    FI: FieldSpec
+{
+    pub(crate) bits: FI::Ux,
     _reg: marker::PhantomData<FI>,
 }
 
-impl<U, FI> FieldReaderRaw<U, FI>
-where
-    U: Copy,
-{
+impl<FI: FieldSpec> FieldReaderRaw<FI> {
     /// Creates a new instance of the reader.
     #[allow(unused)]
     #[inline(always)]
-    pub(crate) fn new(bits: U) -> Self {
+    pub(crate) fn new(bits: FI::Ux) -> Self {
         Self {
             bits,
             _reg: marker::PhantomData,
@@ -322,7 +331,7 @@ where
 }
 
 #[doc(hidden)]
-pub struct BitReaderRaw<FI> {
+pub struct BitReaderRaw<FI = bool> {
     pub(crate) bits: bool,
     _reg: marker::PhantomData<FI>,
 }
@@ -342,30 +351,26 @@ impl<FI> BitReaderRaw<FI> {
 /// Field reader.
 ///
 /// Result of the `read` methods of fields.
-pub type FieldReader<N = u8, FI = u8> = FieldReaderRaw<N, FI>;
+pub type FieldReader<FI = u8> = FieldReaderRaw<FI>;
 
 /// Bit-wise field reader
 pub type BitReader<FI = bool> = BitReaderRaw<FI>;
 
-impl<N, FI> FieldReader<N, FI>
-where
-    N: Copy,
-{
+impl<FI: FieldSpec> FieldReader<FI> {
     /// Reads raw bits from field.
     #[inline(always)]
-    pub fn bits(&self) -> N {
+    pub fn bits(&self) -> FI::Ux {
         self.bits
     }
 }
 
-impl<N, FI> PartialEq<FI> for FieldReader<N, FI>
+impl<FI> PartialEq<FI> for FieldReader<FI>
 where
-    FI: Copy,
-    N: PartialEq + From<FI>,
+    FI: FieldSpec + Copy,
 {
     #[inline(always)]
     fn eq(&self, other: &FI) -> bool {
-        self.bits.eq(&N::from(*other))
+        self.bits.eq(&FI::Ux::from(*other))
     }
 }
 
@@ -404,20 +409,20 @@ pub struct Safe;
 pub struct Unsafe;
 
 #[doc(hidden)]
-pub struct FieldWriterRaw<'a, REG, const WI: u8, const O: u8, N, FI, Safety>
+pub struct FieldWriterRaw<'a, REG, const WI: u8, const O: u8, FI = u8, Safety = Unsafe>
 where
     REG: Writable + RegisterSpec,
-    N: From<FI>,
+    FI: FieldSpec,
 {
     pub(crate) w: &'a mut REG::Writer,
-    _field: marker::PhantomData<(N, FI, Safety)>,
+    _field: marker::PhantomData<(FI, Safety)>,
 }
 
-impl<'a, REG, const WI: u8, const O: u8, N, FI, Safety>
-    FieldWriterRaw<'a, REG, WI, O, N, FI, Safety>
+impl<'a, REG, const WI: u8, const O: u8, FI, Safety>
+    FieldWriterRaw<'a, REG, WI, O, FI, Safety>
 where
     REG: Writable + RegisterSpec,
-    N: From<FI>,
+    FI: FieldSpec,
 {
     /// Creates a new instance of the writer
     #[allow(unused)]
@@ -431,7 +436,7 @@ where
 }
 
 #[doc(hidden)]
-pub struct BitWriterRaw<'a, REG, const O: u8, FI, M>
+pub struct BitWriterRaw<'a, REG, const O: u8, FI = bool, M = BitM>
 where
     REG: Writable + RegisterSpec,
     bool: From<FI>,
@@ -457,25 +462,25 @@ where
 }
 
 /// Write field Proxy with unsafe `bits`
-pub type FieldWriter<'a, REG, const WI: u8, const O: u8, N = u8, FI = u8> =
-    FieldWriterRaw<'a, REG, WI, O, N, FI, Unsafe>;
+pub type FieldWriter<'a, REG, const WI: u8, const O: u8, FI = u8> =
+    FieldWriterRaw<'a, REG, WI, O, FI, Unsafe>;
 /// Write field Proxy with safe `bits`
-pub type FieldWriterSafe<'a, REG, const WI: u8, const O: u8, N = u8, FI = u8> =
-    FieldWriterRaw<'a, REG, WI, O, N, FI, Safe>;
+pub type FieldWriterSafe<'a, REG, const WI: u8, const O: u8, FI = u8> =
+    FieldWriterRaw<'a, REG, WI, O, FI, Safe>;
 
-impl<'a, REG, const WI: u8, const OF: u8, N, FI> FieldWriter<'a, REG, WI, OF, N, FI>
+impl<'a, REG, const WI: u8, const OF: u8, FI> FieldWriter<'a, REG, WI, OF, FI>
 where
     REG: Writable + RegisterSpec,
-    N: From<FI>,
+    FI: FieldSpec,
 {
     /// Field width
     pub const WIDTH: u8 = WI;
 }
 
-impl<'a, REG, const WI: u8, const OF: u8, N, FI> FieldWriterSafe<'a, REG, WI, OF, N, FI>
+impl<'a, REG, const WI: u8, const OF: u8, FI> FieldWriterSafe<'a, REG, WI, OF, FI>
 where
     REG: Writable + RegisterSpec,
-    N: From<FI>,
+    FI: FieldSpec,
 {
     /// Field width
     pub const WIDTH: u8 = WI;
@@ -531,46 +536,46 @@ bit_proxy!(BitWriter0S, Bit0S);
 bit_proxy!(BitWriter1T, Bit1T);
 bit_proxy!(BitWriter0T, Bit0T);
 
-impl<'a, REG, const WI: u8, const OF: u8, N, FI> FieldWriter<'a, REG, WI, OF, N, FI>
+impl<'a, REG, const WI: u8, const OF: u8, FI> FieldWriter<'a, REG, WI, OF, FI>
 where
     REG: Writable + RegisterSpec,
-    REG::Ux: From<N>,
-    N: From<FI>,
+    FI: FieldSpec,
+    REG::Ux: From<FI::Ux>,
 {
     /// Writes raw bits to the field
     ///
     /// # Safety
     ///
     /// Passing incorrect value can cause undefined behaviour. See reference manual
     #[inline(always)]
-    pub unsafe fn bits(self, value: N) -> &'a mut REG::Writer {
+    pub unsafe fn bits(self, value: FI::Ux) -> &'a mut REG::Writer {
         self.w.bits &= !(REG::Ux::mask::<WI>() << OF);
         self.w.bits |= (REG::Ux::from(value) & REG::Ux::mask::<WI>()) << OF;
         self.w
     }
     /// Writes `variant` to the field
     #[inline(always)]
     pub fn variant(self, variant: FI) -> &'a mut REG::Writer {
-        unsafe { self.bits(N::from(variant)) }
+        unsafe { self.bits(FI::Ux::from(variant)) }
     }
 }
-impl<'a, REG, const WI: u8, const OF: u8, N, FI> FieldWriterSafe<'a, REG, WI, OF, N, FI>
+impl<'a, REG, const WI: u8, const OF: u8, FI> FieldWriterSafe<'a, REG, WI, OF, FI>
 where
     REG: Writable + RegisterSpec,
-    REG::Ux: From<N>,
-    N: From<FI>,
+    FI: FieldSpec,
+    REG::Ux: From<FI::Ux>,
 {
     /// Writes raw bits to the field
     #[inline(always)]
-    pub fn bits(self, value: N) -> &'a mut REG::Writer {
+    pub fn bits(self, value: FI::Ux) -> &'a mut REG::Writer {
         self.w.bits &= !(REG::Ux::mask::<WI>() << OF);
         self.w.bits |= (REG::Ux::from(value) & REG::Ux::mask::<WI>()) << OF;
         self.w
     }
     /// Writes `variant` to the field
     #[inline(always)]
     pub fn variant(self, variant: FI) -> &'a mut REG::Writer {
-        self.bits(N::from(variant))
+        self.bits(FI::Ux::from(variant))
     }
 }
 

src/generate/register.rs

@@ -691,12 +691,10 @@ pub fn fields(
                     } else {
                         quote! { crate::BitReader<#value_read_ty> }
                     }
-                } else if fty == "u8" && value_read_ty == "u8" {
-                    quote! { crate::FieldReader }
                 } else if value_read_ty == "u8" {
-                    quote! { crate::FieldReader<#fty> }
+                    quote! { crate::FieldReader }
                 } else {
-                    quote! { crate::FieldReader<#fty, #value_read_ty> }
+                    quote! { crate::FieldReader<#value_read_ty> }
                 };
                 let mut readerdoc = field_reader_brief.clone();
                 if let Some(action) = f.read_action {
@@ -1032,12 +1030,10 @@ pub fn fields(
                         span,
                     );
                     let width = &util::unsuffixed(width as _);
-                    if fty == "u8" && value_write_ty == "u8" {
+                    if value_write_ty == "u8" {
                         quote! { crate::#wproxy<'a, #regspec_ident, #width, O> }
-                    } else if value_write_ty == "u8" {
-                        quote! { crate::#wproxy<'a, #regspec_ident, #width, O, #fty> }
                     } else {
-                        quote! { crate::#wproxy<'a, #regspec_ident, #width, O, #fty, #value_write_ty> }
+                        quote! { crate::#wproxy<'a, #regspec_ident, #width, O, #value_write_ty> }
                     }
                 };
                 mod_items.extend(quote! {
@@ -1246,6 +1242,13 @@ fn add_with_no_variants(
             }
         }
     });
+    if fty != "bool" {
+        mod_items.extend(quote! {
+            impl crate::FieldSpec for #pc {
+                type Ux = #fty;
+            }
+        });
+    }
 }
 
 fn add_from_variants(
@@ -1295,6 +1298,13 @@ fn add_from_variants(
             }
         }
     });
+    if fty != "bool" {
+        mod_items.extend(quote! {
+            impl crate::FieldSpec for #pc {
+                type Ux = #fty;
+            }
+        });
+    }
 }
 
 fn calculate_offset(