Merge branch 'autoload-dsa-tagging-driver-when-dynamically-changing-protocol'

Vladimir Oltean says:

====================
Autoload DSA tagging driver when dynamically changing protocol

This patch set solves the issue reported by Michael and Heiko here:
https://lore.kernel.org/lkml/20221027113248.420216-1-michael@walle.cc/
making full use of Michael's suggestion of having two modaliases: one
gets used for loading the tagging protocol when it's the default one
reported by the switch driver, the other gets loaded at user's request,
by name.

  # modinfo tag_ocelot
  filename:       /lib/modules/6.1.0-rc4+/kernel/net/dsa/tag_ocelot.ko
  license:        GPL v2
  alias:          dsa_tag:seville
  alias:          dsa_tag:id-21
  alias:          dsa_tag:ocelot
  alias:          dsa_tag:id-15
  depends:        dsa_core
  intree:         Y
  name:           tag_ocelot
  vermagic:       6.1.0-rc4+ SMP preempt mod_unload modversions aarch64

Tested on NXP LS1028A-RDB with the following device tree addition:

&mscc_felix_port4 {
	dsa-tag-protocol = "ocelot-8021q";
};

&mscc_felix_port5 {
	dsa-tag-protocol = "ocelot-8021q";
};

CONFIG_NET_DSA and everything that depends on it is built as module.
Everything auto-loads, and "cat /sys/class/net/eno2/dsa/tagging" shows
"ocelot-8021q". Traffic works as well. Furthermore, "echo ocelot-8021q"
into the aforementioned sysfs file now auto-loads the driver for it.
====================

Link: https://lore.kernel.org/r/20221115011847.2843127-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 0 insertions, 70 deletions

diff --git a/include/net/dsa.h b/include/net/dsa.h
index dde364688739..82da44561f4c 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -118,10 +118,6 @@ struct dsa_netdevice_ops {
 			     int cmd);
 };
 
-#define DSA_TAG_DRIVER_ALIAS "dsa_tag-"
-#define MODULE_ALIAS_DSA_TAG_DRIVER(__proto)				\
-	MODULE_ALIAS(DSA_TAG_DRIVER_ALIAS __stringify(__proto##_VALUE))
-
 struct dsa_lag {
 	struct net_device *dev;
 	unsigned int id;
@@ -1400,70 +1396,4 @@ static inline bool dsa_slave_dev_check(const struct net_device *dev)
 netdev_tx_t dsa_enqueue_skb(struct sk_buff *skb, struct net_device *dev);
 void dsa_port_phylink_mac_change(struct dsa_switch *ds, int port, bool up);
 
-struct dsa_tag_driver {
-	const struct dsa_device_ops *ops;
-	struct list_head list;
-	struct module *owner;
-};
-
-void dsa_tag_drivers_register(struct dsa_tag_driver *dsa_tag_driver_array[],
-			      unsigned int count,
-			      struct module *owner);
-void dsa_tag_drivers_unregister(struct dsa_tag_driver *dsa_tag_driver_array[],
-				unsigned int count);
-
-#define dsa_tag_driver_module_drivers(__dsa_tag_drivers_array, __count)	\
-static int __init dsa_tag_driver_module_init(void)			\
-{									\
-	dsa_tag_drivers_register(__dsa_tag_drivers_array, __count,	\
-				 THIS_MODULE);				\
-	return 0;							\
-}									\
-module_init(dsa_tag_driver_module_init);				\
-									\
-static void __exit dsa_tag_driver_module_exit(void)			\
-{									\
-	dsa_tag_drivers_unregister(__dsa_tag_drivers_array, __count);	\
-}									\
-module_exit(dsa_tag_driver_module_exit)
-
-/**
- * module_dsa_tag_drivers() - Helper macro for registering DSA tag
- * drivers
- * @__ops_array: Array of tag driver structures
- *
- * Helper macro for DSA tag drivers which do not do anything special
- * in module init/exit. Each module may only use this macro once, and
- * calling it replaces module_init() and module_exit().
- */
-#define module_dsa_tag_drivers(__ops_array)				\
-dsa_tag_driver_module_drivers(__ops_array, ARRAY_SIZE(__ops_array))
-
-#define DSA_TAG_DRIVER_NAME(__ops) dsa_tag_driver ## _ ## __ops
-
-/* Create a static structure we can build a linked list of dsa_tag
- * drivers
- */
-#define DSA_TAG_DRIVER(__ops)						\
-static struct dsa_tag_driver DSA_TAG_DRIVER_NAME(__ops) = {		\
-	.ops = &__ops,							\
-}
-
-/**
- * module_dsa_tag_driver() - Helper macro for registering a single DSA tag
- * driver
- * @__ops: Single tag driver structures
- *
- * Helper macro for DSA tag drivers which do not do anything special
- * in module init/exit. Each module may only use this macro once, and
- * calling it replaces module_init() and module_exit().
- */
-#define module_dsa_tag_driver(__ops)					\
-DSA_TAG_DRIVER(__ops);							\
-									\
-static struct dsa_tag_driver *dsa_tag_driver_array[] =	{		\
-	&DSA_TAG_DRIVER_NAME(__ops)					\
-};									\
-module_dsa_tag_drivers(dsa_tag_driver_array)
 #endif
-