Merge pull request #731 from rust-embedded/remove-wrappers

generic REG in field writers

Author: therealprof

.github/workflows/ci.yml

@@ -75,7 +75,7 @@ jobs:
           - { rust: stable, vendor: Spansion, options: "--atomics" }
           - { rust: stable, vendor: STMicro, options: "" }
           - { rust: stable, vendor: STMicro, options: "--atomics" }
-          - { rust: stable, vendor: STM32-patched, options: "--strict --const_generic --derive_more --pascal_enum_values --max_cluster_size --atomics" }
+          - { rust: stable, vendor: STM32-patched, options: "--strict --const_generic --pascal_enum_values --max_cluster_size --atomics" }
           - { rust: stable, vendor: Toshiba, options: all }
           - { rust: stable, vendor: Toshiba, options: "" }
           # Test MSRV

CHANGELOG.md

@@ -7,6 +7,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/).
 
 ## [Unreleased]
 
+- removed register writer & reader wrappers, generic `REG` in field writers (#731)
 - Updated syn to version 2 (#732)
 - Let readable field fetch doc from svd description (#734)
 

ci/script.sh

@@ -31,7 +31,7 @@ main() {
 
     case $OPTIONS in
         all)
-            options="--const_generic --strict --derive_more --atomics"
+            options="--const_generic --strict --atomics"
             ;;
         *)
             options=$OPTIONS
@@ -43,9 +43,6 @@ main() {
     echo 'cortex-m = "0.7.4"' >> $td/Cargo.toml
     echo 'cortex-m-rt = "0.7.1"' >> $td/Cargo.toml
     echo 'vcell = "0.1.3"' >> $td/Cargo.toml
-    if [[ "$options" == *"--derive_more"* ]]; then
-        echo 'derive_more = "0.99"' >> $td/Cargo.toml
-    fi
     if [[ "$options" == *"--atomics"* ]]; then
         echo 'portable-atomic = { version = "0.3.16", default-features = false }' >> $td/Cargo.toml
     fi

src/generate/generic.rs

@@ -59,20 +59,14 @@ pub trait FieldSpec: Sized {
 /// Trait implemented by readable registers to enable the `read` method.
 ///
 /// Registers marked with `Writable` can be also be `modify`'ed.
-pub trait Readable: RegisterSpec {
-    /// Result from a call to `read` and argument to `modify`.
-    type Reader: From<R<Self>> + core::ops::Deref<Target = R<Self>>;
-}
+pub trait Readable: RegisterSpec {}
 
 /// Trait implemented by writeable registers.
 ///
 /// This enables the  `write`, `write_with_zero` and `reset` methods.
 ///
 /// Registers marked with `Readable` can be also be `modify`'ed.
 pub trait Writable: RegisterSpec {
-    /// Writer type argument to `write`, et al.
-    type Writer: From<W<Self>> + core::ops::DerefMut<Target = W<Self>>;
-
     /// Specifies the register bits that are not changed if you pass `1` and are changed if you pass `0`
     const ZERO_TO_MODIFY_FIELDS_BITMAP: Self::Ux;
 
@@ -130,11 +124,11 @@ impl<REG: Readable> Reg<REG> {
     /// let flag = reader.field2().bit_is_set();
     /// ```
     #[inline(always)]
-    pub fn read(&self) -> REG::Reader {
-        REG::Reader::from(R {
+    pub fn read(&self) -> R<REG> {
+        R {
             bits: self.register.get(),
             _reg: marker::PhantomData,
-        })
+        }
     }
 }
 
@@ -173,14 +167,14 @@ impl<REG: Resettable + Writable> Reg<REG> {
     #[inline(always)]
     pub fn write<F>(&self, f: F)
     where
-        F: FnOnce(&mut REG::Writer) -> &mut W<REG>,
+        F: FnOnce(&mut W<REG>) -> &mut W<REG>,
     {
         self.register.set(
-            f(&mut REG::Writer::from(W {
+            f(&mut W {
                 bits: REG::RESET_VALUE & !REG::ONE_TO_MODIFY_FIELDS_BITMAP
                     | REG::ZERO_TO_MODIFY_FIELDS_BITMAP,
                 _reg: marker::PhantomData,
-            }))
+            })
             .bits,
         );
     }
@@ -197,13 +191,13 @@ impl<REG: Writable> Reg<REG> {
     #[inline(always)]
     pub unsafe fn write_with_zero<F>(&self, f: F)
     where
-        F: FnOnce(&mut REG::Writer) -> &mut W<REG>,
+        F: FnOnce(&mut W<REG>) -> &mut W<REG>,
     {
         self.register.set(
-            f(&mut REG::Writer::from(W {
+            f(&mut W {
                 bits: REG::Ux::default(),
                 _reg: marker::PhantomData,
-            }))
+            })
             .bits,
         );
     }
@@ -238,20 +232,20 @@ impl<REG: Readable + Writable> Reg<REG> {
     #[inline(always)]
     pub fn modify<F>(&self, f: F)
     where
-        for<'w> F: FnOnce(&REG::Reader, &'w mut REG::Writer) -> &'w mut W<REG>,
+        for<'w> F: FnOnce(&R<REG>, &'w mut W<REG>) -> &'w mut W<REG>,
     {
         let bits = self.register.get();
         self.register.set(
             f(
-                &REG::Reader::from(R {
+                &R {
                     bits,
                     _reg: marker::PhantomData,
-                }),
-                &mut REG::Writer::from(W {
+                },
+                &mut W {
                     bits: bits & !REG::ONE_TO_MODIFY_FIELDS_BITMAP
                         | REG::ZERO_TO_MODIFY_FIELDS_BITMAP,
                     _reg: marker::PhantomData,
-                }),
+                },
             )
             .bits,
         );
@@ -262,7 +256,10 @@ impl<REG: Readable + Writable> Reg<REG> {
 ///
 /// Result of the `read` methods of registers. Also used as a closure argument in the `modify`
 /// method.
-pub struct R<REG: RegisterSpec + ?Sized> {
+pub type R<REG> = RRaw<REG>;
+
+#[doc(hidden)]
+pub struct RRaw<REG: RegisterSpec> {
     pub(crate) bits: REG::Ux,
     _reg: marker::PhantomData<REG>,
 }
@@ -290,25 +287,15 @@ where
 /// Register writer.
 ///
 /// Used as an argument to the closures in the `write` and `modify` methods of the register.
-pub struct W<REG: RegisterSpec + ?Sized> {
+pub type W<REG> = WRaw<REG>;
+
+#[doc(hidden)]
+pub struct WRaw<REG: RegisterSpec> {
     ///Writable bits
     pub(crate) bits: REG::Ux,
     _reg: marker::PhantomData<REG>,
 }
 
-impl<REG: RegisterSpec> W<REG> {
-    /// Writes raw bits to the register.
-    ///
-    /// # Safety
-    ///
-    /// Read datasheet or reference manual to find what values are allowed to pass.
-    #[inline(always)]
-    pub unsafe fn bits(&mut self, bits: REG::Ux) -> &mut Self {
-        self.bits = bits;
-        self
-    }
-}
-
 #[doc(hidden)]
 pub struct FieldReaderRaw<FI = u8>
 where
@@ -414,7 +401,7 @@ where
     REG: Writable + RegisterSpec,
     FI: FieldSpec,
 {
-    pub(crate) w: &'a mut REG::Writer,
+    pub(crate) w: &'a mut W<REG>,
     _field: marker::PhantomData<(FI, Safety)>,
 }
 
@@ -427,7 +414,7 @@ where
     /// Creates a new instance of the writer
     #[allow(unused)]
     #[inline(always)]
-    pub(crate) fn new(w: &'a mut REG::Writer) -> Self {
+    pub(crate) fn new(w: &'a mut W<REG>) -> Self {
         Self {
             w,
             _field: marker::PhantomData,
@@ -441,7 +428,7 @@ where
     REG: Writable + RegisterSpec,
     bool: From<FI>,
 {
-    pub(crate) w: &'a mut REG::Writer,
+    pub(crate) w: &'a mut W<REG>,
     _field: marker::PhantomData<(FI, M)>,
 }
 
@@ -453,7 +440,7 @@ where
     /// Creates a new instance of the writer
     #[allow(unused)]
     #[inline(always)]
-    pub(crate) fn new(w: &'a mut REG::Writer) -> Self {
+    pub(crate) fn new(w: &'a mut W<REG>) -> Self {
         Self {
             w,
             _field: marker::PhantomData,
@@ -514,14 +501,14 @@ macro_rules! impl_bit_proxy {
         {
             /// Writes bit to the field
             #[inline(always)]
-            pub fn bit(self, value: bool) -> &'a mut REG::Writer {
+            pub fn bit(self, value: bool) -> &'a mut W<REG> {
                 self.w.bits &= !(REG::Ux::one() << OF);
                 self.w.bits |= (REG::Ux::from(value) & REG::Ux::one()) << OF;
                 self.w
             }
             /// Writes `variant` to the field
             #[inline(always)]
-            pub fn variant(self, variant: FI) -> &'a mut REG::Writer {
+            pub fn variant(self, variant: FI) -> &'a mut W<REG> {
                 self.bit(bool::from(variant))
             }
         }
@@ -548,14 +535,14 @@ where
     ///
     /// Passing incorrect value can cause undefined behaviour. See reference manual
     #[inline(always)]
-    pub unsafe fn bits(self, value: FI::Ux) -> &'a mut REG::Writer {
+    pub unsafe fn bits(self, value: FI::Ux) -> &'a mut W<REG> {
         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 {
+    pub fn variant(self, variant: FI) -> &'a mut W<REG> {
         unsafe { self.bits(FI::Ux::from(variant)) }
     }
 }
@@ -567,14 +554,14 @@ where
 {
     /// Writes raw bits to the field
     #[inline(always)]
-    pub fn bits(self, value: FI::Ux) -> &'a mut REG::Writer {
+    pub fn bits(self, value: FI::Ux) -> &'a mut W<REG> {
         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 {
+    pub fn variant(self, variant: FI) -> &'a mut W<REG> {
         self.bits(FI::Ux::from(variant))
     }
 }
@@ -594,13 +581,13 @@ where
 {
     /// Sets the field bit
     #[inline(always)]
-    pub fn set_bit(self) -> &'a mut REG::Writer {
+    pub fn set_bit(self) -> &'a mut W<REG> {
         self.w.bits |= REG::Ux::one() << OF;
         self.w
     }
     /// Clears the field bit
     #[inline(always)]
-    pub fn clear_bit(self) -> &'a mut REG::Writer {
+    pub fn clear_bit(self) -> &'a mut W<REG> {
         self.w.bits &= !(REG::Ux::one() << OF);
         self.w
     }
@@ -613,7 +600,7 @@ where
 {
     /// Sets the field bit
     #[inline(always)]
-    pub fn set_bit(self) -> &'a mut REG::Writer {
+    pub fn set_bit(self) -> &'a mut W<REG> {
         self.w.bits |= REG::Ux::one() << OF;
         self.w
     }
@@ -626,7 +613,7 @@ where
 {
     /// Clears the field bit
     #[inline(always)]
-    pub fn clear_bit(self) -> &'a mut REG::Writer {
+    pub fn clear_bit(self) -> &'a mut W<REG> {
         self.w.bits &= !(REG::Ux::one() << OF);
         self.w
     }
@@ -639,7 +626,7 @@ where
 {
     ///Clears the field bit by passing one
     #[inline(always)]
-    pub fn clear_bit_by_one(self) -> &'a mut REG::Writer {
+    pub fn clear_bit_by_one(self) -> &'a mut W<REG> {
         self.w.bits |= REG::Ux::one() << OF;
         self.w
     }
@@ -652,7 +639,7 @@ where
 {
     ///Sets the field bit by passing zero
     #[inline(always)]
-    pub fn set_bit_by_zero(self) -> &'a mut REG::Writer {
+    pub fn set_bit_by_zero(self) -> &'a mut W<REG> {
         self.w.bits &= !(REG::Ux::one() << OF);
         self.w
     }
@@ -665,7 +652,7 @@ where
 {
     ///Toggle the field bit by passing one
     #[inline(always)]
-    pub fn toggle_bit(self) -> &'a mut REG::Writer {
+    pub fn toggle_bit(self) -> &'a mut W<REG> {
         self.w.bits |= REG::Ux::one() << OF;
         self.w
     }
@@ -678,7 +665,7 @@ where
 {
     ///Toggle the field bit by passing zero
     #[inline(always)]
-    pub fn toggle_bit(self) -> &'a mut REG::Writer {
+    pub fn toggle_bit(self) -> &'a mut W<REG> {
         self.w.bits &= !(REG::Ux::one() << OF);
         self.w
     }

src/generate/generic_atomic.rs

@@ -51,12 +51,12 @@ where
     #[inline(always)]
     pub unsafe fn set_bits<F>(&self, f: F)
     where
-        F: FnOnce(&mut REG::Writer) -> &mut W<REG>,
+        F: FnOnce(&mut W<REG>) -> &mut W<REG>,
     {
-        let bits = f(&mut REG::Writer::from(W {
+        let bits = f(&mut W {
             bits: Default::default(),
             _reg: marker::PhantomData,
-        }))
+        })
         .bits;
         REG::Ux::atomic_or(self.register.as_ptr(), bits);
     }
@@ -70,12 +70,12 @@ where
     #[inline(always)]
     pub unsafe fn clear_bits<F>(&self, f: F)
     where
-        F: FnOnce(&mut REG::Writer) -> &mut W<REG>,
+        F: FnOnce(&mut W<REG>) -> &mut W<REG>,
     {
-        let bits = f(&mut REG::Writer::from(W {
+        let bits = f(&mut W {
             bits: !REG::Ux::default(),
             _reg: marker::PhantomData,
-        }))
+        })
         .bits;
         REG::Ux::atomic_and(self.register.as_ptr(), bits);
     }
@@ -89,12 +89,12 @@ where
     #[inline(always)]
     pub unsafe fn toggle_bits<F>(&self, f: F)
     where
-        F: FnOnce(&mut REG::Writer) -> &mut W<REG>,
+        F: FnOnce(&mut W<REG>) -> &mut W<REG>,
     {
-        let bits = f(&mut REG::Writer::from(W {
+        let bits = f(&mut W {
             bits: Default::default(),
             _reg: marker::PhantomData,
-        }))
+        })
         .bits;
         REG::Ux::atomic_xor(self.register.as_ptr(), bits);
     }