driver core: fw_devlink: Consolidate device link flag computation

Consolidate the code that computes the flags to be used when creating a
device link from a fwnode link.

Fixes: 2de9d8e ("driver core: fw_devlink: Improve handling of cyclic dependencies")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Colin Foster <colin.foster@in-advantage.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Luca Weiss <luca.weiss@fairphone.com> # qcom/sm7225-fairphone-fp4
Link: https://lore.kernel.org/r/20230207014207.1678715-8-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Saravana Kannan

drivers/base/core.c

@@ -1727,8 +1727,11 @@ static int __init fw_devlink_strict_setup(char *arg)
 }
 early_param("fw_devlink.strict", fw_devlink_strict_setup);
 
-u32 fw_devlink_get_flags(void)
+static inline u32 fw_devlink_get_flags(u8 fwlink_flags)
 {
+	if (fwlink_flags & FWLINK_FLAG_CYCLE)
+		return FW_DEVLINK_FLAGS_PERMISSIVE | DL_FLAG_CYCLE;
+
 	return fw_devlink_flags;
 }
 
@@ -1938,7 +1941,7 @@ static bool fwnode_ancestor_init_without_drv(struct fwnode_handle *fwnode)
  * fw_devlink_create_devlink - Create a device link from a consumer to fwnode
  * @con: consumer device for the device link
  * @sup_handle: fwnode handle of supplier
- * @flags: devlink flags
+ * @link: fwnode link that's being converted to a device link
  *
  * This function will try to create a device link between the consumer device
  * @con and the supplier device represented by @sup_handle.
@@ -1955,10 +1958,17 @@ static bool fwnode_ancestor_init_without_drv(struct fwnode_handle *fwnode)
  *  possible to do that in the future
  */
 static int fw_devlink_create_devlink(struct device *con,
-				     struct fwnode_handle *sup_handle, u32 flags)
+				     struct fwnode_handle *sup_handle,
+				     struct fwnode_link *link)
 {
 	struct device *sup_dev;
 	int ret = 0;
+	u32 flags;
+
+	if (con->fwnode == link->consumer)
+		flags = fw_devlink_get_flags(link->flags);
+	else
+		flags = FW_DEVLINK_FLAGS_PERMISSIVE;
 
 	/*
 	 * In some cases, a device P might also be a supplier to its child node
@@ -2091,7 +2101,6 @@ static void __fw_devlink_link_to_consumers(struct device *dev)
 	struct fwnode_link *link, *tmp;
 
 	list_for_each_entry_safe(link, tmp, &fwnode->consumers, s_hook) {
-		u32 dl_flags = fw_devlink_get_flags();
 		struct device *con_dev;
 		bool own_link = true;
 		int ret;
@@ -2121,14 +2130,13 @@ static void __fw_devlink_link_to_consumers(struct device *dev)
 				con_dev = NULL;
 			} else {
 				own_link = false;
-				dl_flags = FW_DEVLINK_FLAGS_PERMISSIVE;
 			}
 		}
 
 		if (!con_dev)
 			continue;
 
-		ret = fw_devlink_create_devlink(con_dev, fwnode, dl_flags);
+		ret = fw_devlink_create_devlink(con_dev, fwnode, link);
 		put_device(con_dev);
 		if (!own_link || ret == -EAGAIN)
 			continue;
@@ -2169,19 +2177,13 @@ static void __fw_devlink_link_to_suppliers(struct device *dev,
 	bool own_link = (dev->fwnode == fwnode);
 	struct fwnode_link *link, *tmp;
 	struct fwnode_handle *child = NULL;
-	u32 dl_flags;
-
-	if (own_link)
-		dl_flags = fw_devlink_get_flags();
-	else
-		dl_flags = FW_DEVLINK_FLAGS_PERMISSIVE;
 
 	list_for_each_entry_safe(link, tmp, &fwnode->suppliers, c_hook) {
 		int ret;
 		struct device *sup_dev;
 		struct fwnode_handle *sup = link->supplier;
 
-		ret = fw_devlink_create_devlink(dev, sup, dl_flags);
+		ret = fw_devlink_create_devlink(dev, sup, link);
 		if (!own_link || ret == -EAGAIN)
 			continue;
 

include/linux/fwnode.h

@@ -207,7 +207,6 @@ static inline void fwnode_dev_initialized(struct fwnode_handle *fwnode,
 		fwnode->flags &= ~FWNODE_FLAG_INITIALIZED;
 }
 
-extern u32 fw_devlink_get_flags(void);
 extern bool fw_devlink_is_strict(void);
 int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup);
 void fwnode_links_purge(struct fwnode_handle *fwnode);