From dc45ee4e20156887103d5c1f85e9a12cffbd944a Mon Sep 17 00:00:00 2001
From: Mayunk Kulkarni <mdkul22@gmail.com>
Date: Sun, 24 Nov 2024 18:13:41 -0800
Subject: [PATCH] feat(sleep): Option to enter deep sleep after BLE connection
 severed

Introduce a new Kconfig flag to enable enter SLEEP mode on device if BT connection severed from main active profile
---
 app/Kconfig                                  | 13 +++++++++
 app/include/zmk/split/bluetooth/peripheral.h |  5 +++-
 app/src/activity.c                           | 30 +++++++++++++++++++-
 app/src/behaviors/behavior_soft_off.c        |  3 +-
 4 files changed, 47 insertions(+), 4 deletions(-)

diff --git a/app/Kconfig b/app/Kconfig
index b0ffc72ac02..4a710fb5068 100644
--- a/app/Kconfig
+++ b/app/Kconfig
@@ -449,6 +449,19 @@ config ZMK_IDLE_SLEEP_TIMEOUT
 #ZMK_SLEEP
 endif
 
+config ZMK_SLEEP_ON_BLE_DISCONNECT
+    bool "Enable deep sleep on BLE disconnection"
+    depends on ZMK_SLEEP 
+
+if ZMK_SLEEP_ON_BLE_DISCONNECT
+
+config ZMK_SLEEP_DISCONNECT_TIMER
+    int "Milliseconds of disconnection before entering deep sleep"
+    default 600000
+
+# ZMK_SLEEP_ON_BLE_DISCONNECT
+endif
+
 config ZMK_EXT_POWER
     bool "Enable support to control external power output"
     default y
diff --git a/app/include/zmk/split/bluetooth/peripheral.h b/app/include/zmk/split/bluetooth/peripheral.h
index 44ac8062a51..8a4252ed60f 100644
--- a/app/include/zmk/split/bluetooth/peripheral.h
+++ b/app/include/zmk/split/bluetooth/peripheral.h
@@ -6,6 +6,9 @@
 
 #pragma once
 
+#define IS_SPLIT_PERIPHERAL                                                                        \
+    (IS_ENABLED(CONFIG_ZMK_SPLIT) && !IS_ENABLED(CONFIG_ZMK_SPLIT_ROLE_CENTRAL))
+
 bool zmk_split_bt_peripheral_is_connected(void);
 
-bool zmk_split_bt_peripheral_is_bonded(void);
\ No newline at end of file
+bool zmk_split_bt_peripheral_is_bonded(void);
diff --git a/app/src/activity.c b/app/src/activity.c
index 454e91e5da0..841ba8a5409 100644
--- a/app/src/activity.c
+++ b/app/src/activity.c
@@ -4,10 +4,13 @@
  * SPDX-License-Identifier: MIT
  */
 
+#include "zephyr/sys/util_macro.h"
 #include <zephyr/device.h>
 #include <zephyr/init.h>
 #include <zephyr/kernel.h>
 #include <zephyr/sys/poweroff.h>
+#include <zmk/ble.h>
+#include <zmk/split/bluetooth/peripheral.h>
 
 #include <zephyr/logging/log.h>
 
@@ -26,8 +29,29 @@ LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
 #include <zmk/usb.h>
 #endif
 
+#if IS_ENABLED(CONFIG_ZMK_SLEEP_ON_BLE_DISCONNECT)
+#define MAX_DISCONNECT_MS CONFIG_ZMK_SLEEP_DISCONNECT_TIMER
+
+static uint32_t ble_last_time_connected;
+
+static uint32_t get_latest_ble_connection_active_timestamp(void) {
+#if ZMK_BLE_IS_CENTRAL || !IS_ENABLED(CONFIG_ZMK_SPLIT)
+    if (zmk_ble_active_profile_is_connected()) {
+        ble_last_time_connected = k_uptime_get();
+    }
+    return ble_last_time_connected;
+#elif IS_SPLIT_PERIPHERAL
+    if (zmk_split_bt_peripheral_is_connected()) {
+        ble_last_time_connected = k_uptime_get();
+    }
+    return ble_last_time_connected;
+#endif
+}
+#endif
+
 bool is_usb_power_present(void) {
 #if IS_ENABLED(CONFIG_USB_DEVICE_STACK)
+    return false;
     return zmk_usb_is_powered();
 #else
     return false;
@@ -69,7 +93,11 @@ void activity_work_handler(struct k_work *work) {
     int32_t current = k_uptime_get();
     int32_t inactive_time = current - activity_last_uptime;
 #if IS_ENABLED(CONFIG_ZMK_SLEEP)
-    if (inactive_time > MAX_SLEEP_MS && !is_usb_power_present()) {
+    if ((inactive_time > MAX_SLEEP_MS && !is_usb_power_present())
+#if IS_ENABLED(CONFIG_ZMK_SLEEP_ON_BLE_DISCONNECT)
+        || (current - get_latest_ble_connection_active_timestamp()) > MAX_DISCONNECT_MS
+#endif
+    ) {
         // Put devices in suspend power mode before sleeping
         set_state(ZMK_ACTIVITY_SLEEP);
 
diff --git a/app/src/behaviors/behavior_soft_off.c b/app/src/behaviors/behavior_soft_off.c
index fcffd09ae5e..5b8f5b2a29c 100644
--- a/app/src/behaviors/behavior_soft_off.c
+++ b/app/src/behaviors/behavior_soft_off.c
@@ -12,6 +12,7 @@
 
 #include <zmk/pm.h>
 #include <zmk/behavior.h>
+#include <zmk/split/bluetooth/peripheral.h>
 
 LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
 
@@ -24,8 +25,6 @@ struct behavior_soft_off_data {
     uint32_t press_start;
 };
 
-#define IS_SPLIT_PERIPHERAL                                                                        \
-    (IS_ENABLED(CONFIG_ZMK_SPLIT) && !IS_ENABLED(CONFIG_ZMK_SPLIT_ROLE_CENTRAL))
 
 static int behavior_soft_off_init(const struct device *dev) { return 0; };