chore: massive repo reorganization

src/channel.rs

@@ -0,0 +1,67 @@
+//! Inter-task communication channels.
+//!
+//! Each channel connects exactly two tasks:
+//! - [`CommandChannel`]: USB → Radio (host commands)
+//! - [`ResponseChannel`]: Radio → USB (firmware responses)
+//! - [`DisplayCommandChannel`]: USB → Display (on/off/reset)
+//! - [`StatusWatch`]: Radio → Display (observable radio state)
+
+use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
+use embassy_sync::channel::Channel;
+use embassy_sync::watch::Watch;
+
+use crate::protocol::{Command, RadioConfig, Response};
+
+/// Display commands routed from usb_task to display_task.
+#[derive(Debug, Clone, Copy, defmt::Format)]
+pub enum DisplayCommand {
+    On,
+    Off,
+    Reset,
+}
+
+/// USB-to-display command channel (depth 4: display commands are rare events).
+pub type DisplayCommandChannel = Channel<CriticalSectionRawMutex, DisplayCommand, 4>;
+
+/// Host-to-radio command channel (depth 16: buffer bursty host command sequences).
+pub type CommandChannel = Channel<CriticalSectionRawMutex, Command, 16>;
+
+/// Radio-to-host response channel (depth 32: buffer RX packets while USB writes).
+pub type ResponseChannel = Channel<CriticalSectionRawMutex, Response, 32>;
+
+/// Observable radio status for the display task (2 receivers max).
+/// Display always sees the latest state — intermediate updates may be
+/// skipped, which is fine for a status display.
+pub type StatusWatch = Watch<CriticalSectionRawMutex, RadioStatus, 2>;
+
+/// Current radio state exposed to observers (e.g. display).
+#[derive(Debug, Clone, defmt::Format)]
+pub struct RadioStatus {
+    pub state: RadioState,
+    pub config: Option<RadioConfig>,
+    pub rx_count: u32,
+    pub tx_count: u32,
+    pub last_rssi: Option<i16>,
+    pub last_snr: Option<i16>,
+}
+
+/// Radio state machine states.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, defmt::Format)]
+pub enum RadioState {
+    Idle,
+    Receiving,
+    Transmitting,
+}
+
+impl Default for RadioStatus {
+    fn default() -> Self {
+        Self {
+            state: RadioState::Idle,
+            config: None,
+            rx_count: 0,
+            tx_count: 0,
+            last_rssi: None,
+            last_snr: None,
+        }
+    }
+}