state: add deep probe aware helpers to get state

state_by_name itself can't be made deep probe aware as it doesn't have
enough information on what to probe. Board code calling it must instead
itself ensure that the state has been proved (either via initcall
ordering or by calling e.g. of_ensure_probed_by_alias). For
state_by_node we can do it better: We can ensure probe of the supplied
device node. For most purposes, users just want to probe the default
state. This can now be done with state_by_alias("state").

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Link: https://lore.barebox.org/20220202111932.1227416-1-a.fatoum@pengutronix.de
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 19 insertions, 1 deletions

diff --git a/common/state/state.c b/common/state/state.c
index 8c34ae83e5..a614c849c7 100644
--- a/common/state/state.c
+++ b/common/state/state.c
@@ -704,10 +704,12 @@ struct state *state_by_name(const char *name)
  *
  * @node	The of node of the state instance
  */
-struct state *state_by_node(const struct device_node *node)
+struct state *state_by_node(struct device_node *node)
 {
 	struct state *state;
 
+	of_device_ensure_probed(node);
+
 	list_for_each_entry(state, &state_list, list) {
 		if (!strcmp(state->of_path, node->full_name))
 			return state;
@@ -716,6 +718,22 @@ struct state *state_by_node(const struct device_node *node)
 	return NULL;
 }
 
+/*
+ * state_by_alias - find a state instance by alias
+ *
+ * @name	The DT alias of the state instance
+ */
+struct state *state_by_alias(const char *alias)
+{
+	struct device_node *node;
+
+	node = of_find_node_by_alias(NULL, alias);
+	if (!node)
+		return NULL;
+
+	return state_by_node(node);
+}
+
 int state_read_mac(struct state *state, const char *name, u8 *buf)
 {
 	struct state_variable *svar;