feat: Add &studio_unlock behavior.

* New behavior allows unlocking the keyboard to allow ZMK Studio to
  make changes.

app/CMakeLists.txt

@@ -63,6 +63,7 @@ if ((NOT CONFIG_ZMK_SPLIT) OR CONFIG_ZMK_SPLIT_ROLE_CENTRAL)
   target_sources_ifdef(CONFIG_ZMK_BEHAVIOR_SENSOR_ROTATE_VAR app PRIVATE src/behaviors/behavior_sensor_rotate_var.c)
   target_sources_ifdef(CONFIG_ZMK_BEHAVIOR_SENSOR_ROTATE_COMMON app PRIVATE src/behaviors/behavior_sensor_rotate_common.c)
   target_sources_ifdef(CONFIG_ZMK_BEHAVIOR_MOUSE_KEY_PRESS app PRIVATE src/behaviors/behavior_mouse_key_press.c)
+  target_sources_ifdef(CONFIG_ZMK_BEHAVIOR_STUDIO_UNLOCK app PRIVATE src/behaviors/behavior_studio_unlock.c)
   target_sources(app PRIVATE src/combo.c)
   target_sources(app PRIVATE src/behaviors/behavior_tap_dance.c)
   target_sources(app PRIVATE src/behavior_queue.c)

app/Kconfig.behaviors

@@ -71,6 +71,11 @@ config ZMK_BEHAVIOR_SENSOR_ROTATE_VAR
     depends on DT_HAS_ZMK_BEHAVIOR_SENSOR_ROTATE_VAR_ENABLED
     select ZMK_BEHAVIOR_SENSOR_ROTATE_COMMON
 
+config ZMK_BEHAVIOR_STUDIO_UNLOCK
+    bool
+    default y
+    depends on DT_HAS_ZMK_BEHAVIOR_STUDIO_UNLOCK_ENABLED && ZMK_STUDIO
+
 config ZMK_BEHAVIOR_MACRO
     bool
     default y

app/dts/behaviors.dtsi

@@ -21,3 +21,4 @@
 #include <behaviors/macros.dtsi>
 #include <behaviors/mouse_key_press.dtsi>
 #include <behaviors/soft_off.dtsi>
+#include <behaviors/studio_unlock.dtsi>

app/dts/behaviors/studio_unlock.dtsi

@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2020 The ZMK Contributors
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+/ {
+    behaviors {
+        studio_unlock: studio_unlock {
+            compatible = "zmk,behavior-studio-unlock";
+            #binding-cells = <0>;
+            display-name = "Studio Unlock";
+        };
+    };
+
+};
+

app/dts/bindings/behaviors/zmk,behavior-studio-unlock.yaml

@@ -0,0 +1,8 @@
+# Copyright (c) 2020 The ZMK Contributors
+# SPDX-License-Identifier: MIT
+
+description: Studio Unlock Behavior
+
+compatible: "zmk,behavior-studio-unlock"
+
+include: zero_param.yaml

app/src/behaviors/behavior_studio_unlock.c

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2020 The ZMK Contributors
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#define DT_DRV_COMPAT zmk_behavior_studio_unlock
+
+#include <zephyr/device.h>
+#include <drivers/behavior.h>
+#include <zephyr/logging/log.h>
+
+#include <zmk/behavior.h>
+#include <zmk/studio/core.h>
+
+LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
+
+#if DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT)
+
+static int behavior_studio_unlock_init(const struct device *dev) { return 0; };
+
+static int on_keymap_binding_pressed(struct zmk_behavior_binding *binding,
+                                     struct zmk_behavior_binding_event event) {
+    zmk_studio_core_unlock();
+
+    return ZMK_BEHAVIOR_OPAQUE;
+}
+
+static int on_keymap_binding_released(struct zmk_behavior_binding *binding,
+                                      struct zmk_behavior_binding_event event) {
+    return ZMK_BEHAVIOR_OPAQUE;
+}
+
+static const struct behavior_driver_api behavior_studio_unlock_driver_api = {
+    .binding_pressed = on_keymap_binding_pressed,
+    .binding_released = on_keymap_binding_released,
+#if IS_ENABLED(CONFIG_ZMK_BEHAVIOR_METADATA)
+    .get_parameter_metadata = zmk_behavior_get_empty_param_metadata,
+#endif // IS_ENABLED(CONFIG_ZMK_BEHAVIOR_METADATA)
+};
+
+BEHAVIOR_DT_INST_DEFINE(0, behavior_studio_unlock_init, NULL, NULL, NULL, POST_KERNEL,
+                        CONFIG_KERNEL_INIT_PRIORITY_DEFAULT, &behavior_studio_unlock_driver_api);
+
+#endif /* DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT) */

docs/docs/behaviors/studio-unlock.md

@@ -0,0 +1,25 @@
+---
+title: Studio Unlock Behavior
+sidebar_label: Studio Lock
+---
+
+:::warn
+ZMK Studio is still in active development. This behavior is documented in preparation for it's general availability.
+:::
+
+## Summary
+
+## Studio Unlock
+
+The studio unlock behavior is used to grant ZMK Studio access to make changes to your ZMK device. The device will remain unlocked until a certain amount of time of inactivity in ZMK Studio, or on disconnect. Those trigger events for relocking can be configured with [studio configuration](../config/studio.md).
+
+### Behavior Binding
+
+- Reference: `&studio_unlock`
+- Parameters: None
+
+Example:
+
+```dts
+&studio_unlock
+```