[PATCH 2/2] eth phy: add mdio bus char device interface

[Wei Li]

Add the notifier for the change of mdio bus, since i wanna that a char device
represents a mii_bus not a mdio_device.

Signed-off-by: Wei Li <liwei1...@163.com>
---
 drivers/net/phy/mdio_bus.c | 21 ++++++++++++++++++++-
 include/linux/mdio.h       |  1 +
 include/linux/phy.h        |  2 ++
 3 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index 24b5511..3821dc8 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -240,10 +240,25 @@ static void mdiobus_release(struct device *d)
        kfree(bus);
 }
 
-static struct class mdio_bus_class = {
+struct class mdio_bus_class = {
        .name           = "mdio_bus",
        .dev_release    = mdiobus_release,
 };
+EXPORT_SYMBOL_GPL(mdio_bus_class);
+
+static BLOCKING_NOTIFIER_HEAD(mdio_bus_notifier_list);
+
+int mdiobus_register_notifier(struct notifier_block *nb)
+{
+    return blocking_notifier_chain_register(
+                               &mdio_bus_notifier_list, nb);
+}
+
+int mdiobus_unregister_notifier(struct notifier_block *nb)
+{
+    return blocking_notifier_chain_unregister(
+                               &mdio_bus_notifier_list, nb);
+}
 
 #if IS_ENABLED(CONFIG_OF_MDIO)
 /* Helper function for of_mdio_find_bus */
@@ -418,6 +433,8 @@ int __mdiobus_register(struct mii_bus *bus, struct module 
*owner)
        mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device);
 
        bus->state = MDIOBUS_REGISTERED;
+       blocking_notifier_call_chain(&mdio_bus_notifier_list,
+                                       BUS_NOTIFY_ADD_DEVICE, &bus->dev);
        pr_info("%s: probed\n", bus->name);
        return 0;
 
@@ -446,6 +463,8 @@ void mdiobus_unregister(struct mii_bus *bus)
        int i;
 
        BUG_ON(bus->state != MDIOBUS_REGISTERED);
+       blocking_notifier_call_chain(&mdio_bus_notifier_list,
+                                       BUS_NOTIFY_DEL_DEVICE, &bus->dev);
        bus->state = MDIOBUS_UNREGISTERED;
 
        for (i = 0; i < PHY_MAX_ADDR; i++) {
diff --git a/include/linux/mdio.h b/include/linux/mdio.h
index 2cfffe5..29ab455 100644
--- a/include/linux/mdio.h
+++ b/include/linux/mdio.h
@@ -79,6 +79,7 @@ void mdio_device_reset(struct mdio_device *mdiodev, int 
value);
 int mdio_driver_register(struct mdio_driver *drv);
 void mdio_driver_unregister(struct mdio_driver *drv);
 int mdio_device_bus_match(struct device *dev, struct device_driver *drv);
+extern struct class mdio_bus_class;
 
 static inline bool mdio_phy_id_is_c45(int phy_id)
 {
diff --git a/include/linux/phy.h b/include/linux/phy.h
index f0b5870..39f2609 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -246,6 +246,8 @@ int __mdiobus_register(struct mii_bus *bus, struct module 
*owner);
 #define mdiobus_register(bus) __mdiobus_register(bus, THIS_MODULE)
 void mdiobus_unregister(struct mii_bus *bus);
 void mdiobus_free(struct mii_bus *bus);
+int mdiobus_register_notifier(struct notifier_block *nb);
+int mdiobus_unregister_notifier(struct notifier_block *nb);
 struct mii_bus *devm_mdiobus_alloc_size(struct device *dev, int sizeof_priv);
 static inline struct mii_bus *devm_mdiobus_alloc(struct device *dev)
 {
-- 
2.1.4