Updated USB suspend implementaion

rp2040/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "cmdr-keyboard"
 version = "0.2.0"
-edition = "2024"
+edition = "2021"
 
 [dependencies]
 cortex-m = "0.7.2"

rp2040/src/keyboard.rs

@@ -1,9 +1,91 @@
 //! Keyboard state management and HID report generation.
 
+use crate::hardware;
 use crate::{NUMBER_OF_KEYS, KeyMatrix, KeyReport};
 use crate::layout;
 use crate::status::StatusSummary;
 use usbd_human_interface_device::page::Keyboard;
+use usb_device::device::UsbDeviceState;
+
+/// Tracks USB lifecycle state (suspend/idle/activity) for the keyboard HID device.
+pub struct UsbState {
+    pub initialized: bool,
+    pub active: bool,
+    pub suspended: bool,
+    pub wake_on_input: bool,
+    pub idle_mode: bool,
+    activity: bool,
+    activity_elapsed_ms: u32,
+}
+
+impl UsbState {
+    pub const fn new() -> Self {
+        Self {
+            initialized: false,
+            active: false,
+            suspended: false,
+            wake_on_input: false,
+            idle_mode: false,
+            activity: false,
+            activity_elapsed_ms: 0,
+        }
+    }
+
+    pub fn on_poll(&mut self) {
+        if !self.initialized {
+            self.initialized = true;
+        }
+        if !self.active {
+            self.mark_activity();
+        }
+        self.active = true;
+    }
+
+    pub fn mark_activity(&mut self) {
+        self.activity = true;
+        self.activity_elapsed_ms = 0;
+        self.idle_mode = false;
+    }
+
+    pub fn handle_input_activity(&mut self) {
+        self.mark_activity();
+        if self.suspended && self.wake_on_input {
+            self.wake_on_input = false;
+        }
+    }
+
+    pub fn on_suspend_change(&mut self, state: UsbDeviceState) {
+        let was_suspended = self.suspended;
+        self.suspended = state == UsbDeviceState::Suspend;
+
+        match (was_suspended, self.suspended) {
+            (true, false) => {
+                self.mark_activity();
+                self.wake_on_input = false;
+            }
+            (false, true) => {
+                self.idle_mode = true;
+                self.activity = false;
+                self.wake_on_input = true;
+            }
+            _ => {}
+        }
+    }
+
+    pub fn advance_idle_timer(&mut self, interval_ms: u32) {
+        if !self.activity {
+            return;
+        }
+        self.activity_elapsed_ms = self.activity_elapsed_ms.saturating_add(interval_ms);
+        if self.activity_elapsed_ms >= hardware::timers::IDLE_TIMEOUT_MS {
+            self.activity = false;
+            self.activity_elapsed_ms = 0;
+            self.idle_mode = true;
+        }
+    }
+
+    pub fn acknowledge_report(&mut self) {}
+}
 
 /// Captures per-key state transitions and the function layer active when it was pressed.
 #[derive(Copy, Clone, Default, Debug, PartialEq, Eq)]
@@ -38,6 +120,7 @@ pub struct KeyboardState {
     sticky_key: Keyboard,
     caps_lock_active: bool,
     started: bool,
+    usb: UsbState,
 }
 
 impl KeyboardState {
@@ -49,6 +132,7 @@ impl KeyboardState {
             sticky_key: Keyboard::NoEventIndicated,
             caps_lock_active: false,
             started: false,
+            usb: UsbState::new(),
         }
     }
 
@@ -79,11 +163,18 @@ impl KeyboardState {
     pub fn mark_started(&mut self) {
         // Note that the HID interface has successfully exchanged reports.
         self.started = true;
+        self.usb.mark_activity();
+        self.usb.active = true;
+        self.usb.initialized = true;
     }
 
     pub fn mark_stopped(&mut self) {
         // Reset the flag when USB communication fails.
         self.started = false;
+        self.usb.active = false;
+        self.usb.initialized = false;
+        self.usb.activity = false;
+        self.usb.idle_mode = false;
     }
 
     pub fn started(&self) -> bool {
@@ -107,22 +198,17 @@ impl KeyboardState {
         };
     }
 
-    pub fn status_summary(
+    pub fn status_summary(&self) -> StatusSummary {
-        &self,
-        usb_initialized: bool,
-        usb_active: bool,
-        usb_suspended: bool,
-        idle_mode: bool,
-    ) -> StatusSummary {
         // Produce a condensed summary consumed by the status LED driver.
+        let usb_active = self.usb.active && !self.usb.idle_mode;
         StatusSummary::new(
             self.caps_lock_active,
             matches!(self.sticky_state, StickyState::Armed),
             matches!(self.sticky_state, StickyState::Latched),
-            usb_initialized,
+            self.usb.initialized,
             usb_active,
-            usb_suspended,
+            self.usb.suspended,
-            idle_mode,
+            self.usb.idle_mode,
         )
     }
 
@@ -187,6 +273,14 @@ impl KeyboardState {
 
         active_fn_keys.min(2)
     }
+
+    pub fn usb_state(&mut self) -> &mut UsbState {
+        &mut self.usb
+    }
+
+    pub fn usb(&self) -> &UsbState {
+        &self.usb
+    }
 }
 
 impl Default for KeyboardState {
@@ -246,8 +340,7 @@ mod tests {
         let mut state = KeyboardState::new();
         state.update_caps_lock(true);
         state.mark_started();
-
+        let summary = state.status_summary();
-        let summary = state.status_summary(true, true, false, false);
         assert!(summary.caps_lock_active);
         assert!(summary.usb_active);
         assert!(summary.usb_initialized);

rp2040/src/main.rs

@@ -4,6 +4,7 @@
 //! Email:   cm@cmtec.se
 //! License: Please refer to LICENSE in root directory
 
+//! Firmware entry orchestrating the CMDR Keyboard runtime loop.
 #![no_std]
 #![no_main]
 
@@ -13,45 +14,18 @@ use embedded_hal_0_2::timer::CountDown;
 use fugit::ExtU32;
 use panic_halt as _;
 use usb_device::UsbError;
-use usb_device::device::UsbDeviceState;
 use usb_device::prelude::*;
 use usbd_human_interface_device::device::keyboard::NKROBootKeyboardConfig;
 use usbd_human_interface_device::page::Keyboard;
 use usbd_human_interface_device::prelude::UsbHidError;
 use usbd_human_interface_device::prelude::*;
 
-// The boot2 image must live in the dedicated ROM section, which requires these attributes.
+// Embed the boot2 image for the W25Q080 flash; required for RP2040 to boot from external flash.
-#[unsafe(link_section = ".boot2")]
+#[link_section = ".boot2"]
-#[unsafe(no_mangle)]
+#[no_mangle]
 #[used]
 pub static BOOT2_FIRMWARE: [u8; 256] = rp2040_boot2::BOOT_LOADER_W25Q080;
 
-
-fn handle_usb_state_changes(
-    usb_dev: &UsbDevice<rp2040_hal::usb::UsbBus>,
-    usb_suspended: &mut bool,
-    wake_on_input: &mut bool,
-    last_activity_ms: &mut u32,
-    status_time_ms: u32,
-) {
-    // Track suspend/resume transitions and refresh idle timers when USB wakes.
-    let current_suspended = usb_dev.state() == UsbDeviceState::Suspend;
-    let was_suspended = *usb_suspended;
-
-    match (was_suspended, current_suspended) {
-        (true, false) => {
-            *last_activity_ms = status_time_ms;
-            *wake_on_input = false;
-        }
-        (false, true) => {
-            *wake_on_input = true;
-        }
-        _ => {}
-    }
-
-    *usb_suspended = current_suspended;
-}
-
 #[rp2040_hal::entry]
 fn main() -> ! {
     // Bring up the board peripherals and split them into reusable parts.
@@ -94,38 +68,30 @@ fn main() -> ! {
     status_tick.start(timers::STATUS_LED_INTERVAL_MS.millis());
 
     let mut status_time_ms: u32 = 0;
-    let mut usb_initialized = false;
+    let mut suspended_scan_counter: u8 = 0;
-    let mut usb_suspended = false;
-    let mut wake_on_input = false;
-    let mut last_activity_ms: u32 = 0;
-    let mut suspended_scan_divider: u8 = 0;
 
     loop {
         if status_tick.wait().is_ok() {
             // Update the status LED summary on its cadence.
             status_time_ms = status_time_ms.saturating_add(timers::STATUS_LED_INTERVAL_MS);
-            let idle_elapsed = status_time_ms.saturating_sub(last_activity_ms);
+            {
-            let idle_mode = usb_initialized && idle_elapsed >= timers::IDLE_TIMEOUT_MS;
+                keyboard_state
-            let usb_active = usb_initialized && !idle_mode;
+                    .usb_state()
-            status_led.apply_summary(
+                    .advance_idle_timer(timers::STATUS_LED_INTERVAL_MS);
-                keyboard_state.status_summary(
+            }
-                    usb_initialized,
+            let summary = keyboard_state.status_summary();
-                    usb_active,
+            status_led.apply_summary(summary, status_time_ms);
-                    usb_suspended,
-                    idle_mode,
-                ),
-                status_time_ms,
-            );
         }
 
-        // When suspended, thin out scans to reduce power but keep responsiveness.
+        let should_scan = {
-        const SUSPENDED_SCAN_PERIOD: u8 = 20;
+            const SUSPENDED_SCAN_PERIOD: u8 = 20;
-        let should_scan = if !usb_suspended {
+            if keyboard_state.usb().suspended {
-            suspended_scan_divider = 0;
+                suspended_scan_counter = (suspended_scan_counter + 1) % SUSPENDED_SCAN_PERIOD;
-            true
+                suspended_scan_counter == 0
-        } else {
+            } else {
-            suspended_scan_divider = (suspended_scan_divider + 1) % SUSPENDED_SCAN_PERIOD;
+                suspended_scan_counter = 0;
-            suspended_scan_divider == 0
+                true
+            }
         };
 
         if usb_tick.wait().is_ok() && should_scan {
@@ -134,7 +100,7 @@ fn main() -> ! {
             let pressed_keys = button_matrix.buttons_pressed();
 
             if bootloader::chord_requested(&pressed_keys) {
-                if !usb_suspended {
+                if !keyboard_state.usb().suspended {
                     for _ in 0..3 {
                         let clear_report: KeyReport = [Keyboard::NoEventIndicated; hardware::NUMBER_OF_KEYS];
                         match keyboard.device().write_report(clear_report) {
@@ -152,24 +118,18 @@ fn main() -> ! {
             }
 
             if pressed_keys.iter().any(|pressed| *pressed) {
-                last_activity_ms = status_time_ms;
+                keyboard_state.usb_state().handle_input_activity();
-                if wake_on_input && usb_suspended {
-                    wake_on_input = false;
-                }
             }
 
             let keyboard_report = keyboard_state.process_scan(pressed_keys);
 
-            if !usb_suspended {
+            if !keyboard_state.usb().suspended {
                 // Try to send the generated report to the host.
                 match keyboard.device().write_report(keyboard_report) {
                     Err(UsbHidError::WouldBlock) | Err(UsbHidError::Duplicate) => {}
-                    Ok(_) => {
+                    Ok(_) => {}
-                        usb_initialized = true;
-                    }
                     Err(_) => {
                         keyboard_state.mark_stopped();
-                        usb_initialized = false;
                     }
                 }
             }
@@ -178,34 +138,26 @@ fn main() -> ! {
                 Err(UsbHidError::WouldBlock) | Ok(_) => {}
                 Err(_) => {
                     keyboard_state.mark_stopped();
-                    usb_initialized = false;
                 }
             }
         }
 
         if usb_dev.poll(&mut [&mut keyboard]) {
+            keyboard_state.usb_state().on_poll();
             // Consume OUT reports (e.g., LED indicators) and track host activity.
             match keyboard.device().read_report() {
                 Err(UsbError::WouldBlock) => {}
                 Err(_) => {
                     keyboard_state.mark_stopped();
-                    usb_initialized = false;
                 }
                 Ok(leds) => {
                     keyboard_state.update_caps_lock(leds.caps_lock);
                     keyboard_state.mark_started();
-                    usb_initialized = true;
-                    last_activity_ms = status_time_ms;
                 }
             }
         }
-
+        keyboard_state
-        handle_usb_state_changes(
+            .usb_state()
-            &usb_dev,
+            .on_suspend_change(usb_dev.state());
-            &mut usb_suspended,
-            &mut wake_on_input,
-            &mut last_activity_ms,
-            status_time_ms,
-        );
     }
 }