diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 919259cb..6e5c3d69 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -56,8 +56,8 @@ jobs:
         include:
           - { rust: stable, vendor: Atmel, options: all }
           - { rust: stable, vendor: Atmel, options: "" }
-          - { rust: stable, vendor: Freescale, options: all }
-          - { rust: stable, vendor: Freescale, options: "" }
+          - { rust: stable, vendor: Freescale, options: "--strict --atomics --ident-format register::c:" }
+          - { rust: stable, vendor: Freescale, options: "--ident-format register::c:" }
           - { rust: stable, vendor: Fujitsu, options: "" }
           - { rust: stable, vendor: Fujitsu, options: "--atomics" }
           - { rust: stable, vendor: GD32, options: all }
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 01223973..10564a51 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,7 +8,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/).
 ## [Unreleased]
 
 - Add `base-address-shift` config flag
-- Use `PascalCase` for type idents, fix case changing bugs
+- Use `PascalCase` for type idents, fix case changing bugs, add `--ident-format` (`-f`) option flag
 
 ## [v0.31.5] - 2024-01-04
 
diff --git a/src/main.rs b/src/main.rs
index f8ace936..756bdb1c 100755
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,12 +1,13 @@
 #![recursion_limit = "128"]
 
 use log::{debug, error, info};
+use svd2rust::util::{Case, IdentFormat};
 
 use std::io::Write;
 use std::process;
 use std::{fs::File, path::Path};
 
-use anyhow::{Context, Result};
+use anyhow::{anyhow, Context, Result};
 use clap::{Arg, ArgAction, Command};
 
 use svd2rust::{
@@ -18,6 +19,8 @@ use svd2rust::{
 fn parse_configs(app: Command) -> Result<Config> {
     use irx_config::parsers::{cmd, toml};
     use irx_config::ConfigBuilder;
+    let ident_formats = app.clone().get_matches();
+    dbg!(&ident_formats);
     let irxconfig = ConfigBuilder::default()
         .append_parser(cmd::ParserBuilder::new(app).exit_on_error(true).build()?)
         .append_parser(
@@ -29,7 +32,81 @@ fn parse_configs(app: Command) -> Result<Config> {
         )
         .load()?;
 
-    irxconfig.get().map_err(Into::into)
+    let mut config: Config = irxconfig.get()?;
+    if let Some(ident_formats) = ident_formats.get_many::<String>("ident_format") {
+        for f in ident_formats {
+            let mut f = f.split(":");
+            dbg!(f.clone().count());
+            if let (Some(n), Some(p), Some(c), Some(s)) = (f.next(), f.next(), f.next(), f.next()) {
+                let fmts = &mut config.ident_formats;
+                let case = match c {
+                    "" => None,
+                    "p" | "pascal" | "type" => Some(Case::Pascal),
+                    "s" | "snake" | "lower" => Some(Case::Snake),
+                    "c" | "constant" | "upper" => Some(Case::Constant),
+                    _ => return Err(anyhow!("Unknown case")),
+                };
+                let id_f = IdentFormat {
+                    case,
+                    prefix: p.into(),
+                    suffix: s.into(),
+                };
+                dbg!(&id_f);
+                match n {
+                    "field_reader" => {
+                        fmts.field_reader = id_f;
+                    }
+                    "enum_name" => {
+                        fmts.enum_name = id_f;
+                    }
+                    "enum_write_name" => {
+                        fmts.enum_write_name = id_f;
+                    }
+                    "enum_value" => {
+                        fmts.enum_value = id_f;
+                    }
+                    "interrupt" => {
+                        fmts.interrupt = id_f;
+                    }
+                    "cluster" => {
+                        fmts.cluster = id_f;
+                    }
+                    "cluster_accessor" => {
+                        fmts.cluster_accessor = id_f;
+                    }
+                    //"cluster_mod" => {
+                    //    fmts.cluster_mod = id_f;
+                    //},
+                    "register" => {
+                        fmts.register = id_f;
+                    }
+                    "register_spec" => {
+                        fmts.register_spec = id_f;
+                    }
+                    "register_accessor" => {
+                        fmts.register_accessor = id_f;
+                    }
+                    //"register_mod" => {
+                    //    fmts.register_mod = id_f;
+                    //},
+                    "peripheral" => {
+                        fmts.peripheral = id_f;
+                    }
+                    "peripheral_sigleton" => {
+                        fmts.peripheral_sigleton = id_f;
+                    }
+                    //"peripheral_mod" => {
+                    //    fmts.peripheral_mod = id_f;
+                    //},
+                    "peripheral_feature" => {
+                        fmts.peripheral_feature = id_f;
+                    }
+                    _ => {}
+                }
+            }
+        }
+    }
+    Ok(config)
 }
 
 fn run() -> Result<()> {
@@ -119,6 +196,14 @@ fn run() -> Result<()> {
                 .action(ArgAction::SetTrue)
                 .help("Use independent cfg feature flags for each peripheral"),
         )
+        .arg(
+            Arg::new("ident_format")
+                .long("ident-format")
+                .short('f')
+                .alias("ident_format")
+                .action(ArgAction::Append)
+                .help("Specify prefix, case and suffix for identifier type"),
+        )
         .arg(
             Arg::new("max_cluster_size")
                 .long("max-cluster-size")