Allow for building layouts from keymap.json files.

build_layout.mk

@@ -3,8 +3,14 @@ LAYOUTS_REPOS := $(patsubst %/,%,$(sort $(dir $(wildcard $(LAYOUTS_PATH)/*/))))
 
 define SEARCH_LAYOUTS_REPO
     LAYOUT_KEYMAP_PATH := $$(LAYOUTS_REPO)/$$(LAYOUT)/$$(KEYMAP)
+    LAYOUT_KEYMAP_JSON := $$(LAYOUT_KEYMAP_PATH)/keymap.json
     LAYOUT_KEYMAP_C := $$(LAYOUT_KEYMAP_PATH)/keymap.c
-    ifneq ("$$(wildcard $$(LAYOUT_KEYMAP_C))","")
+    ifneq ("$$(wildcard $$(LAYOUT_KEYMAP_JSON))","")
+        -include $$(LAYOUT_KEYMAP_PATH)/rules.mk
+        KEYMAP_C := $(KEYBOARD_OUTPUT)/src/keymap.c
+        KEYMAP_JSON := $$(LAYOUT_KEYMAP_JSON)
+        KEYMAP_PATH := $$(LAYOUT_KEYMAP_PATH)
+    else ifneq ("$$(wildcard $$(LAYOUT_KEYMAP_C))","")
         -include $$(LAYOUT_KEYMAP_PATH)/rules.mk
         KEYMAP_C := $$(LAYOUT_KEYMAP_C)
         KEYMAP_PATH := $$(LAYOUT_KEYMAP_PATH)
@@ -24,4 +30,7 @@ ifneq ($(FORCE_LAYOUT),)
     endif
 endif
 
-$(foreach LAYOUT,$(LAYOUTS),$(eval $(call SEARCH_LAYOUTS)))
+$(foreach LAYOUT,$(LAYOUTS),$(eval $(call SEARCH_LAYOUTS)))
+
+# Use rule from build_json.mk, but update prerequisite in case KEYMAP_JSON was updated
+$(KEYBOARD_OUTPUT)/src/keymap.c: $(KEYMAP_JSON)