Migrate to FreeRTOS

src/avclan/hal/cd_timer.h

@@ -1,32 +0,0 @@
-// Copyright (C) 2026 Allen Hill <allenofthehills@gmail.com>
-// SPDX-License-Identifier: GPL-3.0-or-later
-
-// CDChanger periodic-timer HAL: the ~1 Hz tick that drives the CD changer's
-// status updates. The timer hardware is target-specific; the CD changer owns
-// what a tick means (see cdchanger.cc). The device polls cdtimer_pending() and
-// clears the tick with cdtimer_clear().
-
-#pragma once
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-// One-time hardware bring-up. Leaves the tick disabled.
-void cdtimer_init(void *ptr, void(clbk)(void *), bool(isplay)(void *));
-
-// Reset the count so the next tick is ~1 s out, and enable the tick.
-void cdtimer_reset(void);
-
-// Restore / disable the ~1 Hz tick.
-void cdtimer_restore(void);
-void cdtimer_disable(void);
-
-extern volatile bool cdtimer_pending_flag;
-
-static inline bool cdtimer_pending() { return cdtimer_pending_flag; }
-static inline void cdtimer_clear() { cdtimer_pending_flag = false; }
-
-#ifdef __cplusplus
-}
-#endif

src/avclan/hal/phy.h

@@ -7,6 +7,8 @@
 
 #include <stdint.h>
 
+#include "FreeRTOS.h" // IWYU pragma: export
+
 #include "avclan.h"
 
 #ifdef __cplusplus
@@ -30,21 +32,16 @@ void phy_mute(bool mute);
 // Non-mutating (e.g. theoretically const qualified/-able)
 bool phy_is_muted(void);
 
-// Withhold acknowledgement. Unlike mute this leaves TX alone: a deaf device
-// can still manipulate the bus/send frames, it just never responds (e.g. ACK,
-// etc). An empty implementation is sufficient for synchronous ports.
+// Do not respond to or log incoming frames. Can still send frames.
 void phy_deafen(bool deaf);
 
-// True when there is a frame to read. This may reflect current bus state (e.g.
-// a frame can be synchronously read from the bus) or indicate that a buffered
-// frame is available to "read".
-bool phy_frame_pending(void);
+// Blocks until a frame is ready
+void phy_wait_frame(TickType_t xTicksToWait);
 
 // Bus-transaction guard: quiesce the other async sources (e.g. interrupts)
 // so that bus read/send timing isn't disturbed. Re-enable relevant async
 // sources with `phy_guard_leave`.
-//  - May be a no-op on a target where contention isn't a concern.
-//  - May acquire a hardware lock to prevent concurrent use
+//  - May be a no-op on a target where concurrency/preemption isn't a concern.
 void phy_guard_enter(void);
 void phy_guard_leave(void);
 
@@ -67,8 +64,9 @@ void phy_guard_leave(void);
  *
  * `expect_ack` indicates whether the recipient should be ACK'ing; false for
  * broadcast frames which don't have a single recipient.
- *
  */
+
+// Returns NO_FRAME when there is no frame to read.
 Read phy_read_header(bool *is_unicast);
 Read phy_read_controller_addr(uint16_t *addr);
 Read phy_read_peripheral_addr(uint16_t *addr);

src/avclan/hal/stdio.h

@@ -12,8 +12,8 @@ extern "C" {
 
 // Generic stdio interface initialization. All user I/O goes through <stdio.h>
 // functions. Assumptions/invariants:
-//  - stdin MUST be non-blocking (ie. a libc read yields EOF immediately when no
-//    input is buffered). Necessary to avoid stalling the REPL poll loop.
+//  - A libc read of stdin blocks the calling task (not the CPU) until at least
+//    one byte is available.
 //  - stdout is *raw*. There is no '\n' -> "\r\n" translation. The port does not
 //    change a bare LF or a binary frame payload. Writes through
 //    <stdio.h> and writes through stdio_write_nonblock() must reach the same