added a lock screen key

keyboards/planck/keymaps/callum/keymap.c

@@ -20,7 +20,8 @@ enum planck_keycodes {
   BASE = SAFE_RANGE,
   MOVE,
   SYMB,
-  FUNC
+  FUNC,
+  LOCK
 };
 
 // Fillers to make layering more clear
@@ -87,7 +88,7 @@ const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
  * ,-----------------------------------------------------------------------------------.
  * | F12  |  F1  |  F2  |  F3  |  F4  |  F5  |  F6  |  F7  |  F8  |  F9  | F10  | F11  |
  * |-----------------------------------------------------------------------------------.
- * |      | Play | Prev | Next | BL+  |      |      |      |      |      |      |      |
+ * |      | Play | Prev | Next | BL+  |      |      | Lock |      |      |      |      |
  * |------+------+------+------+------+------|------+------+------+------+------+------|
  * |      | Mute | Vol- | Vol+ | BL-  |      |      |      |      |      |      |      |
  * |------+------+------+------+------+------+------+------+------+------+------+------|
@@ -96,7 +97,7 @@ const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
  */
 [_FUNC] = {
   {KC_F12,  KC_F1,   KC_F2,   KC_F3,   KC_F4,   KC_F5,   KC_F6,   KC_F7,   KC_F8,   KC_F9,   KC_F10,  KC_F11 },
-  {_______, KC_MPLY, KC_MPRV, KC_MNXT, KC_PAUS, _______, _______, _______, _______, _______, _______, _______},
+  {_______, KC_MPLY, KC_MPRV, KC_MNXT, KC_PAUS, _______, _______, LOCK,    _______, _______, _______, _______},
   {_______, KC_MUTE, KC_VOLD, KC_VOLU, KC_SLCK, _______, _______, _______, _______, _______, _______, _______},
   {_______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, RESET  }
 }
@@ -133,6 +134,18 @@ bool process_record_user(uint16_t keycode, keyrecord_t *record) {
       }
       return false;
       break;
+    case LOCK:
+      if (record->event.pressed) {
+        register_code(KC_RSFT);
+        register_code(KC_RGUI);
+        register_code(KC_POWER);
+      } else {
+        unregister_code(KC_POWER);
+        unregister_code(KC_RGUI);
+        unregister_code(KC_RSFT);
+      }
+      return false;
+      break;
   }
   return true;
 }