From 8b5793e1d08a76a6ad8ddea73e1784f6bb791017 Mon Sep 17 00:00:00 2001
From: okhsunrog <me@okhsunrog.dev>
Date: Wed, 14 Jan 2026 23:20:47 +0300
Subject: [PATCH] Use portable-atomic in cs.rs for ESP32 compatibility

The critical-section coordination module (cs.rs) was using
core::sync::atomic types directly, which don't work on targets
like riscv32imc (ESP32-C3) that lack native atomic support.

This change:
- Uses portable-atomic for AtomicBool and AtomicUsize in cs.rs
- Adds portable-atomic as an optional dependency enabled by
  the critical-section feature
- Removes maitake-sync?/critical-section propagation since cs.rs
  doesn't need it, and it enables portable-atomic/critical-section
  which conflicts with esp-hal's unsafe-assume-single-core cfg

This allows bbqueue to work on ESP32 chips where esp-hal configures
portable-atomic with unsafe-assume-single-core for atomic operations.
---
 bbqueue/Cargo.toml                    | 7 ++++++-
 bbqueue/src/lib.rs                    | 2 +-
 bbqueue/src/traits/coordination/cs.rs | 7 +++----
 3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/bbqueue/Cargo.toml b/bbqueue/Cargo.toml
index 0b22f57..7fc2691 100644
--- a/bbqueue/Cargo.toml
+++ b/bbqueue/Cargo.toml
@@ -33,6 +33,11 @@ version = "1.0"
 default-features = false
 optional = true
 
+[dependencies.portable-atomic]
+version = "1.0"
+default-features = false
+optional = true
+
 [dev-dependencies.tokio]
 version = "1.0"
 features = ["macros", "rt", "time"]
@@ -45,7 +50,7 @@ default = [
 ]
 critical-section = [
     "dep:critical-section",
-    "maitake-sync?/critical-section",
+    "dep:portable-atomic",
 ]
 disable-cache-padding = [
     "maitake-sync?/no-cache-pad",
diff --git a/bbqueue/src/lib.rs b/bbqueue/src/lib.rs
index 6a6d303..74bfbf4 100644
--- a/bbqueue/src/lib.rs
+++ b/bbqueue/src/lib.rs
@@ -127,9 +127,9 @@ pub mod prod_cons;
 /// Queue storage
 ///
 mod queue;
-pub use queue::BBQueue;
 #[cfg(feature = "alloc")]
 pub use queue::ArcBBQueue;
+pub use queue::BBQueue;
 
 /// Generic traits
 ///
diff --git a/bbqueue/src/traits/coordination/cs.rs b/bbqueue/src/traits/coordination/cs.rs
index 5c5dd47..16dec32 100644
--- a/bbqueue/src/traits/coordination/cs.rs
+++ b/bbqueue/src/traits/coordination/cs.rs
@@ -6,10 +6,9 @@
 use const_init::ConstInit;
 
 use super::{Coord, ReadGrantError, WriteGrantError};
-use core::{
-    cmp::min,
-    sync::atomic::{AtomicBool, AtomicUsize, Ordering},
-};
+use core::cmp::min;
+use core::sync::atomic::Ordering;
+use portable_atomic::{AtomicBool, AtomicUsize};
 
 /// Coordination that uses a critical section to perform coordination operations
 ///