From 9c3724b2e13c5d0e3a635ad50bf099dfe1fa9abc Mon Sep 17 00:00:00 2001
From: Ivan Malison <IvanMalison@gmail.com>
Date: Mon, 20 Jul 2026 12:28:14 -0700
Subject: [PATCH] fix split BLE DFU notification readiness

---
 rmk/src/split/ble/peripheral.rs | 20 +++++++++++++++++++-
 rmk/src/split/peripheral.rs     |  2 +-
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/rmk/src/split/ble/peripheral.rs b/rmk/src/split/ble/peripheral.rs
index cff1b2e8e..43a1ba2a5 100644
--- a/rmk/src/split/ble/peripheral.rs
+++ b/rmk/src/split/ble/peripheral.rs
@@ -68,6 +68,12 @@ impl<'stack, 'server, 'c, P: PacketPool> SplitReader for BleSplitPeripheralDrive
                     return Err(SplitDriverError::Disconnected);
                 }
                 GattConnectionEvent::Gatt { event: gatt_event } => {
+                    #[cfg(feature = "dfu_split")]
+                    let split_notifications_cccd_written = matches!(
+                        &gatt_event,
+                        GattEvent::Write(event)
+                            if Some(event.handle()) == self.message_to_central.cccd_handle
+                    );
                     match &gatt_event {
                         GattEvent::Read(event) => {
                             info!("Gatt read event: {:?}", event.handle());
@@ -96,6 +102,14 @@ impl<'stack, 'server, 'c, P: PacketPool> SplitReader for BleSplitPeripheralDrive
                         Ok(r) => r.send().await,
                         Err(e) => warn!("[gatt] error sending response: {:?}", e),
                     }
+                    // Accepting the CCCD write updates TrouBLE's subscription state.
+                    // Announce only when this write enabled notifications.
+                    #[cfg(feature = "dfu_split")]
+                    if split_notifications_cccd_written && self.message_to_central.should_notify(self.conn) {
+                        let hash = crate::dfu::read_embedded_firmware_hash();
+                        info!("dfu_split: notifications enabled, announcing hash {:#x}", hash);
+                        self.write(&SplitMessage::FirmwareHashResponse(hash)).await.ok();
+                    }
                 }
                 GattConnectionEvent::ConnectionParamsUpdated {
                     conn_interval,
@@ -131,7 +145,11 @@ impl<'stack, 'server, 'c, P: PacketPool> SplitWriter for BleSplitPeripheralDrive
             .notify(self.conn, &buf, true)
             .await
             .map_err(|e| {
-                error!("BLE notify error: {:?}", e);
+                if e == Error::NotSubscribed {
+                    debug!("Central has not subscribed to split notifications yet");
+                } else {
+                    error!("BLE notify error: {:?}", e);
+                }
                 SplitDriverError::BleError(1)
             })?;
         Ok(buf.len())
diff --git a/rmk/src/split/peripheral.rs b/rmk/src/split/peripheral.rs
index f1a84104e..4e0eed705 100644
--- a/rmk/src/split/peripheral.rs
+++ b/rmk/src/split/peripheral.rs
@@ -80,7 +80,7 @@ impl<S: SplitWriter + SplitReader> SplitPeripheral<S> {
     pub(crate) async fn run(&mut self) {
         // Proactively announce our firmware hash so the central can detect
         // us even when it booted first and already gave up waiting for a query response.
-        #[cfg(feature = "dfu_split")]
+        #[cfg(all(feature = "dfu_split", not(feature = "_ble")))]
         {
             let hash = crate::dfu::read_embedded_firmware_hash();
             self.split_driver