diff --git a/builddefs/generic_features.mk b/builddefs/generic_features.mk
index 4e058dcd2659..00649f734888 100644
--- a/builddefs/generic_features.mk
+++ b/builddefs/generic_features.mk
@@ -30,6 +30,7 @@ GENERIC_FEATURES = \
HAPTIC \
KEY_LOCK \
KEY_OVERRIDE \
+ LAYER_LOCK \
LEADER \
PROGRAMMABLE_BUTTON \
REPEAT_KEY \
diff --git a/data/constants/keycodes/keycodes_0.0.4.hjson b/data/constants/keycodes/keycodes_0.0.4.hjson
new file mode 100644
index 000000000000..63153daa73c8
--- /dev/null
+++ b/data/constants/keycodes/keycodes_0.0.4.hjson
@@ -0,0 +1,11 @@
+{
+ "keycodes": {
+ "0x7C7B": {
+ "group": "quantum",
+ "key": "QK_LAYER_LOCK",
+ "aliases": [
+ "QK_LLCK"
+ ]
+ }
+ }
+}
diff --git a/data/constants/keycodes/keycodes_0.0.4_quantum.hjson b/data/constants/keycodes/keycodes_0.0.4_quantum.hjson
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/data/mappings/info_config.hjson b/data/mappings/info_config.hjson
index ab9a4a0e4527..cdd14e33fbdc 100644
--- a/data/mappings/info_config.hjson
+++ b/data/mappings/info_config.hjson
@@ -49,6 +49,9 @@
"DYNAMIC_KEYMAP_EEPROM_MAX_ADDR": {"info_key": "dynamic_keymap.eeprom_max_addr", "value_type": "int"},
"DYNAMIC_KEYMAP_LAYER_COUNT": {"info_key": "dynamic_keymap.layer_count", "value_type": "int"},
+ // Layer locking
+ "LAYER_LOCK_IDLE_TIMEOUT": {"info_key": "layer_lock.timeout", "value_type": "int"},
+
// Indicators
"LED_CAPS_LOCK_PIN": {"info_key": "indicators.caps_lock"},
"LED_NUM_LOCK_PIN": {"info_key": "indicators.num_lock"},
diff --git a/data/schemas/keyboard.jsonschema b/data/schemas/keyboard.jsonschema
index e32b88133d1a..b79586ad092b 100644
--- a/data/schemas/keyboard.jsonschema
+++ b/data/schemas/keyboard.jsonschema
@@ -271,6 +271,12 @@
}
},
"keycodes": {"$ref": "qmk.definitions.v1#/keycode_decl_array"},
+ "layer_lock": {
+ "type": "object",
+ "properties": {
+ "timeout": {"$ref": "qmk.definitions.v1#/unsigned_int"}
+ }
+ },
"layout_aliases": {
"type": "object",
"additionalProperties": {"$ref": "qmk.definitions.v1#/layout_macro"}
diff --git a/quantum/keyboard.c b/quantum/keyboard.c
index bb44576ba1b5..912087f02437 100644
--- a/quantum/keyboard.c
+++ b/quantum/keyboard.c
@@ -141,6 +141,9 @@ along with this program. If not, see .
#ifdef ACHORDION_ENABLE
# include "process_achordion.h"
#endif
+#if defined(LAYER_LOCK_ENABLE) && LAYER_LOCK_IDLE_TIMEOUT > 0
+# include "layer_lock.h"
+#endif
static uint32_t last_input_modification_time = 0;
uint32_t last_input_activity_time(void) {
@@ -643,6 +646,10 @@ void quantum_task(void) {
#ifdef ACHORDION_ENABLE
achordion_task();
#endif
+
+#if defined(LAYER_LOCK_ENABLE) && LAYER_LOCK_IDLE_TIMEOUT > 0
+ layer_lock_task();
+#endif
}
/** \brief Main task that is repeatedly called as fast as possible. */
diff --git a/quantum/keycodes.h b/quantum/keycodes.h
index bbf10da36d97..d6011d594ecf 100644
--- a/quantum/keycodes.h
+++ b/quantum/keycodes.h
@@ -1,4 +1,4 @@
-// Copyright 2023 QMK
+// Copyright 2024 QMK
// SPDX-License-Identifier: GPL-2.0-or-later
/*******************************************************************************
@@ -723,6 +723,7 @@ enum qk_keycode_defines {
QK_TRI_LAYER_UPPER = 0x7C78,
QK_REPEAT_KEY = 0x7C79,
QK_ALT_REPEAT_KEY = 0x7C7A,
+ QK_LAYER_LOCK = 0x7C7B,
QK_KB_0 = 0x7E00,
QK_KB_1 = 0x7E01,
QK_KB_2 = 0x7E02,
@@ -1366,6 +1367,7 @@ enum qk_keycode_defines {
TL_UPPR = QK_TRI_LAYER_UPPER,
QK_REP = QK_REPEAT_KEY,
QK_AREP = QK_ALT_REPEAT_KEY,
+ QK_LLCK = QK_LAYER_LOCK,
};
// Range Helpers
@@ -1417,6 +1419,6 @@ enum qk_keycode_defines {
#define IS_MACRO_KEYCODE(code) ((code) >= QK_MACRO_0 && (code) <= QK_MACRO_31)
#define IS_BACKLIGHT_KEYCODE(code) ((code) >= QK_BACKLIGHT_ON && (code) <= QK_BACKLIGHT_TOGGLE_BREATHING)
#define IS_RGB_KEYCODE(code) ((code) >= RGB_TOG && (code) <= RGB_MODE_TWINKLE)
-#define IS_QUANTUM_KEYCODE(code) ((code) >= QK_BOOTLOADER && (code) <= QK_ALT_REPEAT_KEY)
+#define IS_QUANTUM_KEYCODE(code) ((code) >= QK_BOOTLOADER && (code) <= QK_LAYER_LOCK)
#define IS_KB_KEYCODE(code) ((code) >= QK_KB_0 && (code) <= QK_KB_31)
#define IS_USER_KEYCODE(code) ((code) >= QK_USER_0 && (code) <= QK_USER_31)
diff --git a/quantum/layer_lock.c b/quantum/layer_lock.c
new file mode 100644
index 000000000000..3eaf0305b404
--- /dev/null
+++ b/quantum/layer_lock.c
@@ -0,0 +1,81 @@
+// Copyright 2022-2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "layer_lock.h"
+#include "quantum_keycodes.h"
+
+#ifndef NO_ACTION_LAYER
+// The current lock state. The kth bit is on if layer k is locked.
+layer_state_t locked_layers = 0;
+
+// Layer Lock timer to disable layer lock after X seconds inactivity
+# if defined(LAYER_LOCK_IDLE_TIMEOUT) && LAYER_LOCK_IDLE_TIMEOUT > 0
+uint32_t layer_lock_timer = 0;
+
+void layer_lock_task(void) {
+ if (locked_layers && timer_elapsed32(layer_lock_timer) > LAYER_LOCK_IDLE_TIMEOUT) {
+ layer_lock_all_off();
+ layer_lock_timer = timer_read32();
+ }
+}
+# endif // LAYER_LOCK_IDLE_TIMEOUT > 0
+
+bool is_layer_locked(uint8_t layer) {
+ return locked_layers & ((layer_state_t)1 << layer);
+}
+
+void layer_lock_invert(uint8_t layer) {
+ const layer_state_t mask = (layer_state_t)1 << layer;
+ if ((locked_layers & mask) == 0) { // Layer is being locked.
+# ifndef NO_ACTION_ONESHOT
+ if (layer == get_oneshot_layer()) {
+ reset_oneshot_layer(); // Reset so that OSL doesn't turn layer off.
+ }
+# endif // NO_ACTION_ONESHOT
+ layer_on(layer);
+# if defined(LAYER_LOCK_IDLE_TIMEOUT) && LAYER_LOCK_IDLE_TIMEOUT > 0
+ layer_lock_timer = timer_read32();
+# endif // LAYER_LOCK_IDLE_TIMEOUT > 0
+ } else { // Layer is being unlocked.
+ layer_off(layer);
+ }
+ layer_lock_set_user(locked_layers ^= mask);
+}
+
+// Implement layer_lock_on/off by deferring to layer_lock_invert.
+void layer_lock_on(uint8_t layer) {
+ if (!is_layer_locked(layer)) {
+ layer_lock_invert(layer);
+ }
+}
+
+void layer_lock_off(uint8_t layer) {
+ if (is_layer_locked(layer)) {
+ layer_lock_invert(layer);
+ }
+}
+
+void layer_lock_all_off(void) {
+ layer_and(~locked_layers);
+ locked_layers = 0;
+ layer_lock_set_user(locked_layers);
+}
+
+__attribute__((weak)) bool layer_lock_set_kb(layer_state_t locked_layers) {
+ return layer_lock_set_user(locked_layers);
+}
+__attribute__((weak)) bool layer_lock_set_user(layer_state_t locked_layers) {
+ return true;
+}
+#endif // NO_ACTION_LAYER
diff --git a/quantum/layer_lock.h b/quantum/layer_lock.h
new file mode 100644
index 000000000000..40abfa1ffd44
--- /dev/null
+++ b/quantum/layer_lock.h
@@ -0,0 +1,129 @@
+// Copyright 2022-2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/**
+ * @file layer_lock.h
+ * @brief Layer Lock, a key to stay in the current layer.
+ *
+ * Overview
+ * --------
+ *
+ * Layers are often accessed by holding a button, e.g. with a momentary layer
+ * switch `MO(layer)` or layer tap `LT(layer, key)` key. But you may sometimes
+ * want to "lock" or "toggle" the layer so that it stays on without having to
+ * hold down a button. One way to do that is with a tap-toggle `TT` layer key,
+ * but here is an alternative.
+ *
+ * This library implements a "Layer Lock key". When tapped, it "locks" the
+ * highest layer to stay active, assuming the layer was activated by one of the
+ * following keys:
+ *
+ * * `MO(layer)` momentary layer switch
+ * * `LT(layer, key)` layer tap
+ * * `OSL(layer)` one-shot layer
+ * * `TT(layer)` layer tap toggle
+ * * `LM(layer, mod)` layer-mod key (the layer is locked, but not the mods)
+ *
+ * Tapping the Layer Lock key again unlocks and turns off the layer.
+ *
+ * @note When a layer is "locked", other layer keys such as `TO(layer)` or
+ * manually calling `layer_off(layer)` will override and unlock the layer.
+ *
+ * Configuration
+ * -------------
+ *
+ * Optionally, a timeout may be defined so that Layer Lock disables
+ * automatically if not keys are pressed for `LAYER_LOCK_IDLE_TIMEOUT`
+ * milliseconds. Define `LAYER_LOCK_IDLE_TIMEOUT` in your config.h, for instance
+ *
+ * #define LAYER_LOCK_IDLE_TIMEOUT 60000 // Turn off after 60 seconds.
+ *
+ * and call `layer_lock_task()` from your `matrix_scan_user()` in keymap.c:
+ *
+ * void matrix_scan_user(void) {
+ * layer_lock_task();
+ * // Other tasks...
+ * }
+ *
+ * For full documentation, see
+ *
+ */
+
+#pragma once
+
+#include
+#include
+#include "action_layer.h"
+#include "action_util.h"
+
+/**
+ * Handler function for Layer Lock.
+ *
+ * In your keymap, define a custom keycode to use for Layer Lock. Then handle
+ * Layer Lock from your `process_record_user` function by calling
+ * `process_layer_lock`, passing your custom keycode for the `lock_keycode` arg:
+ *
+ * #include "features/layer_lock.h"
+ *
+ * bool process_record_user(uint16_t keycode, keyrecord_t* record) {
+ * if (!process_layer_lock(keycode, record, LLOCK)) { return false; }
+ * // Your macros ...
+ *
+ * return true;
+ * }
+ */
+
+#ifndef NO_ACTION_LAYER
+/** Returns true if `layer` is currently locked. */
+bool is_layer_locked(uint8_t layer);
+
+/** Locks and turns on `layer`. */
+void layer_lock_on(uint8_t layer);
+
+/** Unlocks and turns off `layer`. */
+void layer_lock_off(uint8_t layer);
+
+/** Unlocks and turns off all locked layers. */
+void layer_lock_all_off(void);
+
+/** Toggles whether `layer` is locked. */
+void layer_lock_invert(uint8_t layer);
+
+/**
+ * Optional callback that gets called when a layer is locked or unlocked.
+ *
+ * This is useful to represent the current lock state, e.g. by setting an LED or
+ * playing a sound. In your keymap, define
+ *
+ * void layer_lock_set_user(layer_state_t locked_layers) {
+ * // Do something like `set_led(is_layer_locked(NAV));`
+ * }
+ *
+ * @param locked_layers Bitfield in which the kth bit represents whether the
+ * kth layer is on.
+ */
+bool layer_lock_set_kb(layer_state_t locked_layers);
+bool layer_lock_set_user(layer_state_t locked_layers);
+
+void layer_lock_task(void);
+#else // NO_ACTION_LAYER
+static inline bool is_layer_locked(uint8_t layer) { return false; }
+static inline void layer_lock_on(uint8_t layer) {}
+static inline void layer_lock_off(uint8_t layer) {}
+static inline void layer_lock_all_off(void) {}
+static inline void layer_lock_invert(uint8_t layer) {}
+static inline bool layer_lock_set_kb(layer_state_t locked_layers) { return true; }
+static inline bool layer_lock_set_user(layer_state_t locked_layers) { return true; }
+static inline void layer_lock_task(void) {}
+#endif // NO_ACTION_LAYER
diff --git a/quantum/process_keycode/process_layer_lock.c b/quantum/process_keycode/process_layer_lock.c
new file mode 100644
index 000000000000..1e36d8844e83
--- /dev/null
+++ b/quantum/process_keycode/process_layer_lock.c
@@ -0,0 +1,95 @@
+// Copyright 2022-2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/**
+ * @file layer_lock.c
+ * @brief Layer Lock implementation
+ *
+ * For full documentation, see
+ *
+ */
+
+#include "layer_lock.h"
+#include "process_layer_lock.h"
+#include "quantum_keycodes.h"
+#include "action_util.h"
+
+// The current lock state. The kth bit is on if layer k is locked.
+extern layer_state_t locked_layers;
+#if defined(LAYER_LOCK_IDLE_TIMEOUT) && LAYER_LOCK_IDLE_TIMEOUT > 0
+extern uint32_t layer_lock_timer;
+#endif
+
+// Handles an event on an `MO` or `TT` layer switch key.
+static bool handle_mo_or_tt(uint8_t layer, keyrecord_t* record) {
+ if (is_layer_locked(layer)) {
+ if (record->event.pressed) { // On press, unlock the layer.
+ layer_lock_invert(layer);
+ }
+ return false; // Skip default handling.
+ }
+ return true;
+}
+
+bool process_layer_lock(uint16_t keycode, keyrecord_t* record) {
+#ifndef NO_ACTION_LAYER
+# if defined(LAYER_LOCK_IDLE_TIMEOUT) && LAYER_LOCK_IDLE_TIMEOUT > 0
+ layer_lock_timer = timer_read32();
+# endif // LAYER_LOCK_IDLE_TIMEOUT > 0
+
+ // The intention is that locked layers remain on. If something outside of
+ // this feature turned any locked layers off, unlock them.
+ if ((locked_layers & ~layer_state) != 0) {
+ layer_lock_set_kb(locked_layers &= layer_state);
+ }
+
+ if (keycode == QK_LAYER_LOCK) {
+ if (record->event.pressed) { // The layer lock key was pressed.
+ layer_lock_invert(get_highest_layer(layer_state));
+ }
+ return false;
+ }
+
+ switch (keycode) {
+ case QK_MOMENTARY ... QK_MOMENTARY_MAX: // `MO(layer)` keys.
+ return handle_mo_or_tt(QK_MOMENTARY_GET_LAYER(keycode), record);
+
+ case QK_LAYER_TAP_TOGGLE ... QK_LAYER_TAP_TOGGLE_MAX: // `TT(layer)`.
+ return handle_mo_or_tt(QK_LAYER_TAP_TOGGLE_GET_LAYER(keycode), record);
+
+ case QK_LAYER_MOD ... QK_LAYER_MOD_MAX: { // `LM(layer, mod)`.
+ uint8_t layer = QK_LAYER_MOD_GET_LAYER(keycode);
+ if (is_layer_locked(layer)) {
+ if (record->event.pressed) { // On press, unlock the layer.
+ layer_lock_invert(layer);
+ } else { // On release, clear the mods.
+ clear_mods();
+ send_keyboard_report();
+ }
+ return false; // Skip default handling.
+ }
+ } break;
+
+# ifndef NO_ACTION_TAPPING
+ case QK_LAYER_TAP ... QK_LAYER_TAP_MAX: // `LT(layer, key)` keys.
+ if (record->tap.count == 0 && !record->event.pressed && is_layer_locked(QK_LAYER_TAP_GET_LAYER(keycode))) {
+ // Release event on a held layer-tap key where the layer is locked.
+ return false; // Skip default handling so that layer stays on.
+ }
+ break;
+# endif // NO_ACTION_TAPPING
+ }
+#endif // NO_ACTION_LAYER
+ return true;
+}
diff --git a/quantum/process_keycode/process_layer_lock.h b/quantum/process_keycode/process_layer_lock.h
new file mode 100644
index 000000000000..b54c0f6f1062
--- /dev/null
+++ b/quantum/process_keycode/process_layer_lock.h
@@ -0,0 +1,69 @@
+// Copyright 2022-2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/**
+ * @file layer_lock.h
+ * @brief Layer Lock, a key to stay in the current layer.
+ *
+ * Overview
+ * --------
+ *
+ * Layers are often accessed by holding a button, e.g. with a momentary layer
+ * switch `MO(layer)` or layer tap `LT(layer, key)` key. But you may sometimes
+ * want to "lock" or "toggle" the layer so that it stays on without having to
+ * hold down a button. One way to do that is with a tap-toggle `TT` layer key,
+ * but here is an alternative.
+ *
+ * This library implements a "Layer Lock key". When tapped, it "locks" the
+ * highest layer to stay active, assuming the layer was activated by one of the
+ * following keys:
+ *
+ * * `MO(layer)` momentary layer switch
+ * * `LT(layer, key)` layer tap
+ * * `OSL(layer)` one-shot layer
+ * * `TT(layer)` layer tap toggle
+ * * `LM(layer, mod)` layer-mod key (the layer is locked, but not the mods)
+ *
+ * Tapping the Layer Lock key again unlocks and turns off the layer.
+ *
+ * @note When a layer is "locked", other layer keys such as `TO(layer)` or
+ * manually calling `layer_off(layer)` will override and unlock the layer.
+ *
+ * Configuration
+ * -------------
+ *
+ * Optionally, a timeout may be defined so that Layer Lock disables
+ * automatically if not keys are pressed for `LAYER_LOCK_IDLE_TIMEOUT`
+ * milliseconds. Define `LAYER_LOCK_IDLE_TIMEOUT` in your config.h, for instance
+ *
+ * #define LAYER_LOCK_IDLE_TIMEOUT 60000 // Turn off after 60 seconds.
+ *
+ * and call `layer_lock_task()` from your `matrix_scan_user()` in keymap.c:
+ *
+ * void matrix_scan_user(void) {
+ * layer_lock_task();
+ * // Other tasks...
+ * }
+ *
+ * For full documentation, see
+ *
+ */
+
+#pragma once
+
+#include
+#include
+#include "action.h"
+
+bool process_layer_lock(uint16_t keycode, keyrecord_t* record);
diff --git a/quantum/quantum.c b/quantum/quantum.c
index 00b4de6b1e58..973fe57045d8 100644
--- a/quantum/quantum.c
+++ b/quantum/quantum.c
@@ -72,6 +72,9 @@
#ifdef VELOCIKEY_ENABLE
# include "velocikey.h"
#endif
+#ifdef LAYER_LOCK_ENABLE
+# include "process_layer_lock.h"
+#endif
#ifdef AUDIO_ENABLE
# ifndef GOODBYE_SONG
@@ -397,6 +400,9 @@ bool process_record_quantum(keyrecord_t *record) {
#endif
#ifdef TRI_LAYER_ENABLE
process_tri_layer(keycode, record) &&
+#endif
+#ifdef LAYER_LOCK_ENABLE
+ process_layer_lock(keycode, record) &&
#endif
true)) {
return false;
diff --git a/quantum/quantum.h b/quantum/quantum.h
index 30e86b43007f..4503f356494b 100644
--- a/quantum/quantum.h
+++ b/quantum/quantum.h
@@ -234,7 +234,9 @@ extern layer_state_t layer_state;
# include "repeat_key.h"
# include "process_repeat_key.h"
#endif
-
+#ifdef LAYER_LOCK_ENABLE
+# include "layer_lock.h"
+#endif
void set_single_persistent_default_layer(uint8_t default_layer);
#define IS_LAYER_ON(layer) layer_state_is(layer)
diff --git a/tests/test_common/keycode_table.cpp b/tests/test_common/keycode_table.cpp
index 9ed80cdbcf66..ac4530bb8867 100644
--- a/tests/test_common/keycode_table.cpp
+++ b/tests/test_common/keycode_table.cpp
@@ -1,4 +1,4 @@
-// Copyright 2023 QMK
+// Copyright 2024 QMK
// SPDX-License-Identifier: GPL-2.0-or-later
/*******************************************************************************
@@ -665,6 +665,7 @@ std::map KEYCODE_ID_TABLE = {
{QK_TRI_LAYER_UPPER, "QK_TRI_LAYER_UPPER"},
{QK_REPEAT_KEY, "QK_REPEAT_KEY"},
{QK_ALT_REPEAT_KEY, "QK_ALT_REPEAT_KEY"},
+ {QK_LAYER_LOCK, "QK_LAYER_LOCK"},
{QK_KB_0, "QK_KB_0"},
{QK_KB_1, "QK_KB_1"},
{QK_KB_2, "QK_KB_2"},