[PATCH 1/1] device property: Add fwnode_name_eq()

[Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>]

Add fwnode_name_eq() to implement the functionality of of_node_name_eq()
on fwnode property API. The same convention of ending the comparison at
'@' (besides '\0') is applied on also both ACPI and swnode. The function
is intended for comparing unit address-less node names on DT and firmware
or swnodes compliant with DT bindings.

Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
---
Hi Laurent,

Would you be able to use this to replace of_node_name_eq()?

It's fully untested.

I didn't add an op for it as it rather looks like all the implentations
would be the same (but with different container struct).

 drivers/base/property.c  | 28 ++++++++++++++++++++++++++++
 include/linux/property.h |  1 +
 2 files changed, 29 insertions(+)

diff --git a/drivers/base/property.c b/drivers/base/property.c
index 8c40abed7852..766ac3fc8cc5 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -594,6 +594,34 @@ const char *fwnode_get_name_prefix(const struct fwnode_handle *fwnode)
 	return fwnode_call_ptr_op(fwnode, get_name_prefix);
 }
 
+/**
+ * fwnode_name_eq - Return true if node name is equal
+ * @fwnode The firmware node
+ * @name: The name to which to compare the node name
+ *
+ * Compare the name provided as an argument to the name of the node, stopping
+ * the comparison to either '\0' or '@' character, whichever comes first. This
+ * function is generally used for comparing node names while ignoring the
+ * possible unit address of the node.
+ *
+ * Return: true if the node name matches with the name provided in the @name
+ * argument, false otherwise.
+ */
+bool fwnode_name_eq(const struct fwnode_handle *fwnode, const char *name)
+{
+	const char *node_name;
+	unsigned int len;
+
+	node_name = fwnode_get_name(fwnode);
+	if (!node_name)
+		return false;
+
+	len = strchrnul(node_name, '@') - node_name;
+
+	return strlen(name) == len && !strncmp(node_name, name, len);
+}
+EXPORT_SYMBOL_GPL(fwnode_name_eq);
+
 /**
  * fwnode_get_parent - Return parent firwmare node
  * @fwnode: Firmware whose parent is retrieved
diff --git a/include/linux/property.h b/include/linux/property.h
index 083a1f41364b..096ade186601 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -108,6 +108,7 @@ struct fwnode_handle *fwnode_find_reference(const struct fwnode_handle *fwnode,
 
 const char *fwnode_get_name(const struct fwnode_handle *fwnode);
 const char *fwnode_get_name_prefix(const struct fwnode_handle *fwnode);
+bool fwnode_name_eq(const struct fwnode_handle *fwnode, const char *name);
 
 struct fwnode_handle *fwnode_get_parent(const struct fwnode_handle *fwnode);
 struct fwnode_handle *fwnode_get_next_parent(struct fwnode_handle *fwnode);
-- 
2.39.2