displayio: implement, use allocate_new_display_bus_or_raise

2 files changed, 19 insertions, 0 deletions

diff --git a/shared-module/displayio/__init__.c b/shared-module/displayio/__init__.c
index fd58a0322..4844dfe60 100644
--- a/shared-module/displayio/__init__.c
+++ b/shared-module/displayio/__init__.c
@@ -326,3 +326,20 @@ primary_display_t *allocate_display_or_raise() {
 }
 
 }
+primary_display_t *allocate_display_bus(void) {
+    for (uint8_t i = 0; i < CIRCUITPY_DISPLAY_LIMIT; i++) {
+        mp_const_obj_t display_type = displays[i].display.base.type;
+        if (display_type == NULL || display_type == &mp_type_NoneType) {
+            return &displays[i];
+        }
+    }
+    return NULL;
+}
+
+primary_display_t *allocate_display_bus_or_raise(void) {
+    primary_display_t *result = allocate_display_bus();
+    if (result) {
+        return result;
+    }
+    mp_raise_RuntimeError(translate("Too many display busses"));
+}
diff --git a/shared-module/displayio/__init__.h b/shared-module/displayio/__init__.h
index 4e1297c8d..638c2091e 100644
--- a/shared-module/displayio/__init__.h
+++ b/shared-module/displayio/__init__.h
@@ -56,5 +56,7 @@ void displayio_gc_collect(void);
 
 primary_display_t *allocate_display(void);
 primary_display_t *allocate_display_or_raise(void);
+primary_display_t *allocate_display_bus(void);
+primary_display_t *allocate_display_bus_or_raise(void);
 
 #endif // MICROPY_INCLUDED_SHARED_MODULE_DISPLAYIO___INIT___H