move must_use from methods to generic type

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/).
 
 ## [Unreleased]
 
+- move `must_use` from methods to generic type
+
 ## [v0.33.5] - 2024-10-12
 
 - Fix STM32-patched CI

src/generate/generic.rs

@@ -147,6 +147,7 @@ pub mod raw {
         }
     }
 
+    #[must_use = "after creating `FieldWriter` you need to call field value setting method"]
     pub struct FieldWriter<'a, REG, const WI: u8, FI = u8, Safety = Unsafe>
     where
         REG: Writable + RegisterSpec,
@@ -174,6 +175,7 @@ pub mod raw {
         }
     }
 
+    #[must_use = "after creating `BitWriter` you need to call bit setting method"]
     pub struct BitWriter<'a, REG, FI = bool, M = BitM>
     where
         REG: Writable + RegisterSpec,

src/generate/register.rs

@@ -1305,7 +1305,6 @@ pub fn fields(
                     #[doc = ""]
                     #[doc = #note]
                     #inline
-                    #[must_use]
                     pub fn #name_snake_case(&mut self, n: u8) -> #writer_ty<#regspec_ty> {
                         #[allow(clippy::no_effect)]
                         [(); #dim][n as usize];
@@ -1326,7 +1325,6 @@ pub fn fields(
                     w_impl_items.extend(quote! {
                         #[doc = #doc]
                         #inline
-                        #[must_use]
                         pub fn #name_snake_case_n(&mut self) -> #writer_ty<#regspec_ty> {
                             #writer_ty::new(self, #sub_offset)
                         }
@@ -1338,7 +1336,6 @@ pub fn fields(
                 w_impl_items.extend(quote! {
                     #[doc = #doc]
                     #inline
-                    #[must_use]
                     pub fn #name_snake_case(&mut self) -> #writer_ty<#regspec_ty> {
                         #writer_ty::new(self, #offset)
                     }