driver core: Delete pointless parameter in fwnode_operations.add_links

[linux-2.6-microblaze.git] / include / linux / fwnode.h

diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h
index 9506f8e..fde4ad9 100644 (file)
--- a/include/linux/fwnode.h
+++ b/include/linux/fwnode.h
@@ -10,14 +10,32 @@
 #define _LINUX_FWNODE_H_
 
 #include <linux/types.h>
+#include <linux/list.h>
 
 struct fwnode_operations;
 struct device;
 
+/*
+ * fwnode link flags
+ *
+ * LINKS_ADDED: The fwnode has already be parsed to add fwnode links.
+ */
+#define FWNODE_FLAG_LINKS_ADDED                BIT(0)
+
 struct fwnode_handle {
        struct fwnode_handle *secondary;
        const struct fwnode_operations *ops;
        struct device *dev;
+       struct list_head suppliers;
+       struct list_head consumers;
+       u8 flags;
+};
+
+struct fwnode_link {
+       struct fwnode_handle *supplier;
+       struct list_head s_hook;
+       struct fwnode_handle *consumer;
+       struct list_head c_hook;
 };
 
 /**
@@ -68,44 +86,8 @@ struct fwnode_reference_args {
  *                            endpoint node.
  * @graph_get_port_parent: Return the parent node of a port node.
  * @graph_parse_endpoint: Parse endpoint for port and endpoint id.
- * @add_links: Called after the device corresponding to the fwnode is added
- *             using device_add(). The function is expected to create device
- *             links to all the suppliers of the device that are available at
- *             the time this function is called.  The function must NOT stop
- *             at the first failed device link if other unlinked supplier
- *             devices are present in the system.  This is necessary for the
- *             driver/bus sync_state() callbacks to work correctly.
- *
- *             For example, say Device-C depends on suppliers Device-S1 and
- *             Device-S2 and the dependency is listed in that order in the
- *             firmware.  Say, S1 gets populated from the firmware after
- *             late_initcall_sync().  Say S2 is populated and probed way
- *             before that in device_initcall(). When C is populated, if this
- *             add_links() function doesn't continue past a "failed linking to
- *             S1" and continue linking C to S2, then S2 will get a
- *             sync_state() callback before C is probed. This is because from
- *             the perspective of S2, C was never a consumer when its
- *             sync_state() evaluation is done. To avoid this, the add_links()
- *             function has to go through all available suppliers of the
- *             device (that corresponds to this fwnode) and link to them
- *             before returning.
- *
- *             If some suppliers are not yet available (indicated by an error
- *             return value), this function will be called again when other
- *             devices are added to allow creating device links to any newly
- *             available suppliers.
- *
- *             Return 0 if device links have been successfully created to all
- *             the known suppliers of this device or if the supplier
- *             information is not known.
- *
- *             Return -ENODEV if the suppliers needed for probing this device
- *             have not been registered yet (because device links can only be
- *             created to devices registered with the driver core).
- *
- *             Return -EAGAIN if some of the suppliers of this device have not
- *             been registered yet, but none of those suppliers are necessary
- *             for probing the device.
+ * @add_links: Create fwnode links to all the suppliers of the fwnode. Return
+ *             zero on success, a negative error code otherwise.
  */
 struct fwnode_operations {
        struct fwnode_handle *(*get)(struct fwnode_handle *fwnode);
@@ -145,8 +127,7 @@ struct fwnode_operations {
        (*graph_get_port_parent)(struct fwnode_handle *fwnode);
        int (*graph_parse_endpoint)(const struct fwnode_handle *fwnode,
                                    struct fwnode_endpoint *endpoint);
-       int (*add_links)(const struct fwnode_handle *fwnode,
-                        struct device *dev);
+       int (*add_links)(struct fwnode_handle *fwnode);
 };
 
 #define fwnode_has_op(fwnode, op)                              \
@@ -170,8 +151,16 @@ struct fwnode_operations {
        } while (false)
 #define get_dev_from_fwnode(fwnode)    get_device((fwnode)->dev)
 
+static inline void fwnode_init(struct fwnode_handle *fwnode,
+                              const struct fwnode_operations *ops)
+{
+       fwnode->ops = ops;
+       INIT_LIST_HEAD(&fwnode->consumers);
+       INIT_LIST_HEAD(&fwnode->suppliers);
+}
+
 extern u32 fw_devlink_get_flags(void);
-void fw_devlink_pause(void);
-void fw_devlink_resume(void);
+int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup);
+void fwnode_links_purge(struct fwnode_handle *fwnode);
 
 #endif