avionic design with actual uboot and tooling

submodule of avionic design uboot bootloader and with included tools to
get you started , read readme.md and readme-tk1-loader.md

u-boot/drivers/led/led-uclass.c

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <led.h>
+#include <dm/root.h>
+#include <dm/uclass-internal.h>
+
+int led_get_by_label(const char *label, struct udevice **devp)
+{
+	struct udevice *dev;
+	struct uclass *uc;
+	int ret;
+
+	ret = uclass_get(UCLASS_LED, &uc);
+	if (ret)
+		return ret;
+	uclass_foreach_dev(dev, uc) {
+		struct led_uclass_plat *uc_plat = dev_get_uclass_platdata(dev);
+
+		/* Ignore the top-level LED node */
+		if (uc_plat->label && !strcmp(label, uc_plat->label))
+			return uclass_get_device_tail(dev, 0, devp);
+	}
+
+	return -ENODEV;
+}
+
+int led_set_on(struct udevice *dev, int on)
+{
+	struct led_ops *ops = led_get_ops(dev);
+
+	if (!ops->set_on)
+		return -ENOSYS;
+
+	return ops->set_on(dev, on);
+}
+
+UCLASS_DRIVER(led) = {
+	.id		= UCLASS_LED,
+	.name		= "led",
+	.per_device_platdata_auto_alloc_size = sizeof(struct led_uclass_plat),
+};