Non-volatile memory data repository pattern (#24356)

* First batch of eeconfig conversions.

* Offset and length for datablocks.

* `via`, `dynamic_keymap`.

* Fix filename.

* Commentary.

* wilba leds

* satisfaction75

* satisfaction75

* more keyboard whack-a-mole

* satisfaction75

* omnikeyish

* more whack-a-mole

* `generic_features.mk` to automatically pick up nvm repositories

* thievery

* deferred variable resolve

* whitespace

* convert api to structs/unions

* convert api to structs/unions

* convert api to structs/unions

* fixups

* code-side docs

* code size fix

* rollback

* nvm_xxxxx_erase

* Updated location of eeconfig magic numbers so non-EEPROM nvm drivers can use them too.

* Fixup build.

* Fixup compilation error with encoders.

* Build fixes.

* Add `via_ci` keymap to onekey to exercise VIA bindings (and thus dynamic keymap et.al.), fixup compilation errors based on preprocessor+sizeof.

* Build failure rectification.

keyboards/handwired/onekey/keymaps/via_ci/config.h

@@ -0,0 +1,4 @@
+// Copyright 2025 Nick Brassel (@tzarc)
+// SPDX-License-Identifier: GPL-2.0-or-later
+#pragma once
+#define TRANSIENT_EEPROM_SIZE 160

keyboards/handwired/onekey/keymaps/via_ci/keymap.c

@@ -0,0 +1,30 @@
+// Copyright 2025 Nick Brassel (@tzarc)
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include QMK_KEYBOARD_H
+
+enum custom_keycodes {
+    KC_HELLO = SAFE_RANGE,
+};
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+    LAYOUT_ortho_1x1(KC_HELLO)
+};
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+    switch (keycode) {
+        case KC_HELLO:
+            if (record->event.pressed) {
+                send_string_P("Hello world!");
+            }
+            return false;
+    }
+    return true;
+}
+
+void keyboard_post_init_user(void) {
+  // Customise these values to desired behaviour
+  debug_enable=true;
+  debug_matrix=true;
+  //debug_keyboard=true;
+  //debug_mouse=true;
+}

keyboards/handwired/onekey/keymaps/via_ci/keymap.json

@@ -0,0 +1,7 @@
+{
+    "config": {
+        "features": {
+            "via": true
+        }
+    }
+}

keyboards/handwired/onekey/teensy_32/rules.mk

@@ -0,0 +1 @@
+EEPROM_DRIVER = transient

keyboards/handwired/onekey/teensy_lc/rules.mk

@@ -1,2 +1,2 @@
 USE_CHIBIOS_CONTRIB = yes
-
+EEPROM_DRIVER = transient

keyboards/handwired/ortho_brass/keymaps/default/keymap.c

@@ -182,9 +182,9 @@ bool process_record_user(uint16_t keycode, keyrecord_t *record) {
                 if (!eeconfig_is_enabled()) {
                     eeconfig_init();
                 }
-                keymap_config.raw  = eeconfig_read_keymap();
+                eeconfig_read_keymap(&keymap_config);
                 keymap_config.nkro = 1;
-                eeconfig_update_keymap(keymap_config.raw);
+                eeconfig_update_keymap(&keymap_config);
             }
             return false;
             break;