dm: core: Support writing a boolean

Add functions to write a boolean property. This involves deleting it if
the value is false.

Add a new ofnode_has_property() as well. Add a comment about the behaviour
of of_read_property() when the property value is empty.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 34 insertions, 2 deletions

diff --git a/drivers/core/ofnode.c b/drivers/core/ofnode.c
index 39ba480c8f8..4dcb3dd1c03 100644
--- a/drivers/core/ofnode.c
+++ b/drivers/core/ofnode.c
@@ -491,12 +491,12 @@ u64 ofnode_read_u64_default(ofnode node, const char *propname, u64 def)
 
 bool ofnode_read_bool(ofnode node, const char *propname)
 {
-	const void *prop;
+	bool prop;
 
 	assert(ofnode_valid(node));
 	debug("%s: %s: ", __func__, propname);
 
-	prop = ofnode_get_property(node, propname, NULL);
+	prop = ofnode_has_property(node, propname);
 
 	debug("%s\n", prop ? "true" : "false");
 
@@ -1168,6 +1168,14 @@ const void *ofnode_get_property(ofnode node, const char *propname, int *lenp)
 				   propname, lenp);
 }
 
+bool ofnode_has_property(ofnode node, const char *propname)
+{
+	if (ofnode_is_np(node))
+		return of_find_property(ofnode_to_np(node), propname, NULL);
+	else
+		return ofnode_get_property(node, propname, NULL);
+}
+
 int ofnode_first_property(ofnode node, struct ofprop *prop)
 {
 	prop->node = node;
@@ -1616,6 +1624,30 @@ int ofnode_write_u32(ofnode node, const char *propname, u32 value)
 	return ofnode_write_prop(node, propname, val, sizeof(value), false);
 }
 
+int ofnode_write_bool(ofnode node, const char *propname, bool value)
+{
+	if (value)
+		return ofnode_write_prop(node, propname, NULL, 0, false);
+	else
+		return ofnode_delete_prop(node, propname);
+}
+
+int ofnode_delete_prop(ofnode node, const char *propname)
+{
+	if (ofnode_is_np(node)) {
+		struct property *prop;
+		int len;
+
+		prop = of_find_property(ofnode_to_np(node), propname, &len);
+		if (prop)
+			return of_remove_property(ofnode_to_np(node), prop);
+		return 0;
+	} else {
+		return fdt_delprop(ofnode_to_fdt(node), ofnode_to_offset(node),
+				   propname);
+	}
+}
+
 int ofnode_set_enabled(ofnode node, bool value)
 {
 	assert(ofnode_valid(node));