Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/base/devcon.c b/drivers/base/devcon.c
index d427e80..14e2178 100644
--- a/drivers/base/devcon.c
+++ b/drivers/base/devcon.c
@@ -7,10 +7,84 @@
  */
 
 #include <linux/device.h>
+#include <linux/property.h>
 
 static DEFINE_MUTEX(devcon_lock);
 static LIST_HEAD(devcon_list);
 
+static void *
+fwnode_graph_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
+			  void *data, devcon_match_fn_t match)
+{
+	struct device_connection con = { .id = con_id };
+	struct fwnode_handle *ep;
+	void *ret;
+
+	fwnode_graph_for_each_endpoint(fwnode, ep) {
+		con.fwnode = fwnode_graph_get_remote_port_parent(ep);
+		if (!fwnode_device_is_available(con.fwnode))
+			continue;
+
+		ret = match(&con, -1, data);
+		fwnode_handle_put(con.fwnode);
+		if (ret) {
+			fwnode_handle_put(ep);
+			return ret;
+		}
+	}
+	return NULL;
+}
+
+static void *
+fwnode_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
+		    void *data, devcon_match_fn_t match)
+{
+	struct device_connection con = { };
+	void *ret;
+	int i;
+
+	for (i = 0; ; i++) {
+		con.fwnode = fwnode_find_reference(fwnode, con_id, i);
+		if (IS_ERR(con.fwnode))
+			break;
+
+		ret = match(&con, -1, data);
+		fwnode_handle_put(con.fwnode);
+		if (ret)
+			return ret;
+	}
+
+	return NULL;
+}
+
+/**
+ * fwnode_connection_find_match - Find connection from a device node
+ * @fwnode: Device node with the connection
+ * @con_id: Identifier for the connection
+ * @data: Data for the match function
+ * @match: Function to check and convert the connection description
+ *
+ * Find a connection with unique identifier @con_id between @fwnode and another
+ * device node. @match will be used to convert the connection description to
+ * data the caller is expecting to be returned.
+ */
+void *fwnode_connection_find_match(struct fwnode_handle *fwnode,
+				   const char *con_id, void *data,
+				   devcon_match_fn_t match)
+{
+	void *ret;
+
+	if (!fwnode || !match)
+		return NULL;
+
+	ret = fwnode_graph_devcon_match(fwnode, con_id, data, match);
+	if (ret)
+		return ret;
+
+	return fwnode_devcon_match(fwnode, con_id, data, match);
+}
+EXPORT_SYMBOL_GPL(fwnode_connection_find_match);
+
 /**
  * device_connection_find_match - Find physical connection to a device
  * @dev: Device with the connection
@@ -23,10 +97,9 @@
  * caller is expecting to be returned.
  */
 void *device_connection_find_match(struct device *dev, const char *con_id,
-			       void *data,
-			       void *(*match)(struct device_connection *con,
-					      int ep, void *data))
+				   void *data, devcon_match_fn_t match)
 {
+	struct fwnode_handle *fwnode = dev_fwnode(dev);
 	const char *devname = dev_name(dev);
 	struct device_connection *con;
 	void *ret = NULL;
@@ -35,6 +108,10 @@
 	if (!match)
 		return NULL;
 
+	ret = fwnode_connection_find_match(fwnode, con_id, data, match);
+	if (ret)
+		return ret;
+
 	mutex_lock(&devcon_lock);
 
 	list_for_each_entry(con, &devcon_list, list) {
@@ -75,12 +152,30 @@
 	NULL,
 };
 
+static void *device_connection_fwnode_match(struct device_connection *con)
+{
+	struct bus_type *bus;
+	struct device *dev;
+
+	for (bus = generic_match_buses[0]; bus; bus++) {
+		dev = bus_find_device_by_fwnode(bus, con->fwnode);
+		if (dev && !strncmp(dev_name(dev), con->id, strlen(con->id)))
+			return dev;
+
+		put_device(dev);
+	}
+	return NULL;
+}
+
 /* This tries to find the device from the most common bus types by name. */
 static void *generic_match(struct device_connection *con, int ep, void *data)
 {
 	struct bus_type *bus;
 	struct device *dev;
 
+	if (con->fwnode)
+		return device_connection_fwnode_match(con);
+
 	for (bus = generic_match_buses[0]; bus; bus++) {
 		dev = bus_find_device_by_name(bus, NULL, con->endpoint[ep]);
 		if (dev)