[PATCH v3 7/7] of_overlay: Add option to apply overlay to live tree

[Sascha Hauer <s.hauer@pengutronix.de>]

The of_overlay command currently only supports applying overlays to the
Linux device tree. Add an option to apply an overlay to the live tree.
Using this option will apply the overlay and also triggers rescanning
the device tree in case new devices have been added.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 commands/of_overlay.c | 38 ++++++++++++++++++++++++++++++++++----
 1 file changed, 34 insertions(+), 4 deletions(-)

diff --git a/commands/of_overlay.c b/commands/of_overlay.c
index b3660b4bf1..1d68e31ef2 100644
--- a/commands/of_overlay.c
+++ b/commands/of_overlay.c
@@ -17,10 +17,20 @@ static int do_of_overlay(int argc, char *argv[])
 	struct fdt_header *fdt;
 	struct device_node *overlay;
 	size_t size;
+	bool live_tree = false;
+	int opt;
 
-	if (argc != 2)
+	if (argc < 2)
 		return COMMAND_ERROR_USAGE;
 
+	while ((opt = getopt(argc, argv, "l")) > 0) {
+		switch (opt) {
+		case 'l':
+			live_tree = true;
+			break;
+		}
+	}
+
 	fdt = read_file(argv[optind], &size);
 	if (!fdt) {
 		printf("cannot read %s\n", argv[optind]);
@@ -32,7 +42,14 @@ static int do_of_overlay(int argc, char *argv[])
 	if (IS_ERR(overlay))
 		return PTR_ERR(overlay);
 
-	ret = of_register_overlay(overlay);
+	if (live_tree) {
+		ret = of_overlay_apply_tree(of_get_root_node(), overlay);
+		if (!ret)
+			ret = of_probe();
+	} else {
+		ret = of_register_overlay(overlay);
+	}
+
 	if (ret) {
 		printf("cannot apply oftree overlay: %s\n", strerror(-ret));
 		goto err;
@@ -45,9 +62,22 @@ err:
 	return ret;
 }
 
+BAREBOX_CMD_HELP_START(of_overlay)
+BAREBOX_CMD_HELP_TEXT("Register a device tree overlay file (dtbo) with barebox.")
+BAREBOX_CMD_HELP_TEXT("By default the overlay is registered as a fixup and the")
+BAREBOX_CMD_HELP_TEXT("overlay will then be applied to the Linux device tree.")
+BAREBOX_CMD_HELP_TEXT("With -l given the overlay is applied to the barebox live")
+BAREBOX_CMD_HELP_TEXT("tree instead. This involves probing new devices added in")
+BAREBOX_CMD_HELP_TEXT("the overlay file.")
+BAREBOX_CMD_HELP_TEXT("")
+BAREBOX_CMD_HELP_TEXT("Options:")
+BAREBOX_CMD_HELP_OPT("-l", "apply to barebox live tree")
+BAREBOX_CMD_HELP_END
+
 BAREBOX_CMD_START(of_overlay)
 	.cmd = do_of_overlay,
-	BAREBOX_CMD_DESC("register device tree overlay as fixup")
-	BAREBOX_CMD_OPTS("FILE")
+	BAREBOX_CMD_DESC("register device tree overlay")
+	BAREBOX_CMD_OPTS("[-l] FILE")
 	BAREBOX_CMD_GROUP(CMD_GRP_MISC)
+	BAREBOX_CMD_HELP(cmd_of_overlay_help)
 BAREBOX_CMD_END
-- 
2.30.2