underglow-layer: use devicetree & clean up code

app/src/rgb_underglow_layer.c

@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2020 The ZMK Contributors
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#include <zephyr/device.h>
+#include <drivers/behavior.h>
+#include <zephyr/sys/util.h>
+#include <zephyr/bluetooth/bluetooth.h>
+#include <zephyr/logging/log.h>
+LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
+
+#include <zmk/matrix.h>
+#include <zmk/keymap.h>
+#include <zmk/rgb_underglow_layer.h>
+
+#if !IS_ENABLED(CONFIG_ZMK_SPLIT_ROLE_CENTRAL)
+#include <zmk/split/bluetooth/peripheral_layers.h>
+#endif
+
+#define DT_DRV_COMPAT zmk_underglow_layer
+
+#define LAYER_ID(node) DT_PROP(node, layer_id)
+#define RGB_BINDINGS(node) DT_PROP(node, bindings)
+
+static uint32_t zmk_rgbmap[ZMK_RGBMAP_LAYERS_LEN][ZMK_KEYMAP_LEN] = {
+    DT_INST_FOREACH_CHILD_SEP(0, RGB_BINDINGS, (, ))
+};
+
+static int zmk_rgbmap_ids[ZMK_RGBMAP_LAYERS_LEN] = {
+    DT_INST_FOREACH_CHILD_SEP(0, LAYER_ID, (, ))};
+
+
+const int zmk_rgbmap_id(uint8_t layer) {
+    for (uint8_t i = 0; i < ZMK_RGBMAP_LAYERS_LEN; i++) {
+        if (zmk_rgbmap_ids[i] == layer) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+uint32_t *rgb_underglow_get_bindings(void) {
+    uint8_t layer = rgb_underglow_top_layer();
+    int rgblayer = zmk_rgbmap_id(layer);
+    if (rgblayer == -1){
+        return NULL;
+    } else {
+        return zmk_rgbmap[rgblayer];
+    }
+}
+
+uint8_t rgb_underglow_top_layer(void) {
+    for (uint8_t layer = ZMK_KEYMAP_LAYERS_LEN - 1; layer > 0; layer--) {
+#if IS_ENABLED(CONFIG_ZMK_SPLIT_ROLE_CENTRAL)
+        if (zmk_keymap_layer_active(layer)) {
+#else
+        if (peripheral_layer_active(layer)) {
+#endif
+            return layer;
+        }
+    }
+    return -1;
+}