Initial refactor to have a shield/board have one default keymap.

* Start of work of focusing on out-of-tree user keymaps.

Add ZMK_CONFIG support.

* General external configuration supported via ZMK_CONFIG,
  which should point to a configuration directory.
* Priority order of overlay files to select.
  * ${SHIELD}_${BOARD}.overlay
  * ${SHIELD}.overlay
  * ${BOARD}.overlay
  * default.overlay
* Equivalent search order for .conf files for initial Kconfig
  values.

3 files changed, 85 insertions, 0 deletions

diff --git a/app/boards/shields/petejohanson_proton_handwire/keymap/include/keymap.h b/app/boards/shields/petejohanson_proton_handwire/keymap/include/keymap.h
new file mode 100644
index 0000000..0fd2f9f
--- /dev/null
+++ b/app/boards/shields/petejohanson_proton_handwire/keymap/include/keymap.h
@@ -0,0 +1,9 @@
+
+#include <dt-bindings/zmk/keys.h>
+
+#define DEFAULT 0
+#define RAISE 1
+#define LOWER 2
+
+#define CC_RAIS ZC_CSTM(RAISE)
+#define CC_LOWR ZC_CSTM(LOWER)
diff --git a/app/boards/shields/petejohanson_proton_handwire/keymap/keymap.c b/app/boards/shields/petejohanson_proton_handwire/keymap/keymap.c
new file mode 100644
index 0000000..bde15ac
--- /dev/null
+++ b/app/boards/shields/petejohanson_proton_handwire/keymap/keymap.c
@@ -0,0 +1,34 @@
+
+#include <zmk/keys.h>
+#include <zmk/keymap.h>
+#include <keymap.h>
+
+bool zmk_handle_key_user(struct zmk_key_event *key_event)
+{
+	switch (key_event->key)
+	{
+	case CC_LOWR:
+		if (key_event->pressed)
+		{
+			zmk_keymap_layer_activate(LOWER);
+		}
+		else
+		{
+			zmk_keymap_layer_deactivate(LOWER);
+		}
+
+		return false;
+	case CC_RAIS:
+		if (key_event->pressed)
+		{
+			zmk_keymap_layer_activate(RAISE);
+		}
+		else
+		{
+			zmk_keymap_layer_deactivate(RAISE);
+		}
+		return false;
+	}
+
+	return true;
+};
diff --git a/app/boards/shields/petejohanson_proton_handwire/keymap/keymap.overlay b/app/boards/shields/petejohanson_proton_handwire/keymap/keymap.overlay
new file mode 100644
index 0000000..c1bd542
--- /dev/null
+++ b/app/boards/shields/petejohanson_proton_handwire/keymap/keymap.overlay
@@ -0,0 +1,42 @@
+#include <dt-bindings/zmk/keys.h>
+#include <keymap.h>
+
+/ {
+	chosen {
+		zmk,keymap = &keymap0;
+	};
+	keymap0: keymap {
+		compatible = "zmk,keymap";
+		label ="Default keymap";
+		layers = <&default &lower &raise>;
+	};
+
+	layers {
+		compatible = "zmk,layers";
+
+		default: layer_0 {
+			label = "DEFAULT";
+			keys =
+	<
+	KC_A MT(MOD_LSFT, KC_B)
+	CC_RAIS CC_LOWR
+	>;
+		};
+
+		lower: layer_1 {
+			label = "LOWER";
+			keys = <
+			KC_MPLY KC_MNXT
+			ZC_TRNS ZC_TRNS
+			>;
+		};
+
+		raise: layer_2 {
+			label = "RAISE";
+			keys = <
+			KC_C KC_D
+			ZC_TRNS ZC_TRNS
+			>;
+		};
+	};
+};