From 66b9ace1d3755892d757977197b0fc4bc7bd277b Mon Sep 17 00:00:00 2001
From: Andrey Zgarbul <zgarbul.andrey@gmail.com>
Date: Sun, 23 Aug 2026 16:06:54 +0300
Subject: [PATCH] sort-fields flag

---
 src/config.rs            | 14 ++++++++++++++
 src/generate/register.rs | 10 +++++++++-
 src/main.rs              |  8 ++++++++
 3 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/src/config.rs b/src/config.rs
index 06b732d9..374cbf7a 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -43,6 +43,7 @@ pub struct Config {
     pub ident_formats: IdentFormats,
     pub ident_formats_theme: Option<IdentFormatsTheme>,
     pub field_names_for_enums: bool,
+    pub sort_fields: SortDir,
     pub base_address_shift: u64,
     /// Path to YAML file with chip-specific settings
     pub settings_file: Option<PathBuf>,
@@ -347,6 +348,19 @@ pub enum IdentFormatsTheme {
     Legacy,
 }
 
+#[cfg_attr(
+    feature = "serde",
+    derive(serde::Deserialize),
+    serde(rename_all = "lowercase")
+)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
+pub enum SortDir {
+    #[default]
+    Direct,
+    Reverse,
+    None,
+}
+
 #[cfg_attr(feature = "serde", derive(serde::Deserialize), serde(default))]
 #[derive(Clone, PartialEq, Eq, Debug, Default)]
 #[non_exhaustive]
diff --git a/src/generate/register.rs b/src/generate/register.rs
index 4bff2b8f..46f0686c 100644
--- a/src/generate/register.rs
+++ b/src/generate/register.rs
@@ -628,7 +628,15 @@ pub fn fields(
     let can_read = access.can_read();
     let can_write = access.can_write();
 
-    fields.sort_by_key(|f| f.bit_offset());
+    match config.sort_fields {
+        crate::config::SortDir::Direct => {
+            fields.sort_by_key(|f| f.bit_offset());
+        }
+        crate::config::SortDir::Reverse => {
+            fields.sort_by_key(|f| -(f.bit_offset() as i32));
+        }
+        crate::config::SortDir::None => {}
+    }
 
     // Hack for #625
     let mut enum_derives = HashSet::new();
diff --git a/src/main.rs b/src/main.rs
index fcee4cc7..8c8fdeb5 100755
--- a/src/main.rs
+++ b/src/main.rs
@@ -200,6 +200,14 @@ Allowed cases are `unchanged` (''), `pascal` ('p'), `constant` ('c') and `snake`
                 .action(ArgAction::SetTrue)
                 .help("Use field name for enumerations even when enumeratedValues has a name"),
         )
+        .arg(
+            Arg::new("sort_fields")
+                .long("sort-fields")
+                .alias("sort_fields")
+                .help("Sort fields direct or reverse by offset")
+                .action(ArgAction::Set)
+                .value_name("DIRECTION"),
+        )
         .arg(
             Arg::new("max_cluster_size")
                 .long("max-cluster-size")