net: phy: Allow pre-declaration of MDIO devices

Allow board support code to collect pre-declarations for MDIO devices by
registering them with mdiobus_register_board_info(). SPI and I2C buses
have a similar feature, we were missing this for MDIO devices, but this
is particularly useful for e.g: MDIO-connected switches which need to
provide their port layout (often board-specific) to a MDIO Ethernet
switch driver.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 19 insertions, 0 deletions

diff --git a/include/linux/phy.h b/include/linux/phy.h
index 28ae9eafec19..d9bdf53e0514 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -886,6 +886,25 @@ void mdio_bus_exit(void);
 
 extern struct bus_type mdio_bus_type;
 
+struct mdio_board_info {
+        const char      *bus_id;
+        char            modalias[MDIO_NAME_SIZE];
+        int             mdio_addr;
+        const void      *platform_data;
+};
+
+#if IS_ENABLED(CONFIG_PHYLIB)
+int mdiobus_register_board_info(const struct mdio_board_info *info,
+                                unsigned int n);
+#else
+static inline int mdiobus_register_board_info(const struct mdio_board_info *i,
+                                              unsigned int n)
+{
+        return 0;
+}
+#endif
+
+
 /**
  * module_phy_driver() - Helper macro for registering PHY drivers
  * @__phy_drivers: array of PHY drivers to register