net: phy: air_en8811h: Add the Airoha EN8811H PHY driver

Add the driver for the Airoha EN8811H 2.5 Gigabit PHY. The phy supports
100/1000/2500 Mbps with auto negotiation only.

The driver uses two firmware files, for which updated versions are added to
linux-firmware already.

Note: At phy-address + 8 there is another device on the mdio bus, that
belongs to the EN881H. While the original driver writes to it, Airoha
has confirmed this is not needed. Therefore, communication with this
device is not included in this driver.

Signed-off-by: Eric Woudstra <ericwouds@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20240326162305.303598-3-ericwouds@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/phy/Kconfig

@@ -76,6 +76,11 @@ config SFP
 
 comment "MII PHY device drivers"
 
+config AIR_EN8811H_PHY
+	tristate "Airoha EN8811H 2.5 Gigabit PHY"
+	help
+	  Currently supports the Airoha EN8811H PHY.
+
 config AMD_PHY
 	tristate "AMD and Altima PHYs"
 	help

drivers/net/phy/Makefile

@@ -34,6 +34,7 @@ obj-y				+= $(sfp-obj-y) $(sfp-obj-m)
 
 obj-$(CONFIG_ADIN_PHY)		+= adin.o
 obj-$(CONFIG_ADIN1100_PHY)	+= adin1100.o
+obj-$(CONFIG_AIR_EN8811H_PHY)   += air_en8811h.o
 obj-$(CONFIG_AMD_PHY)		+= amd.o
 obj-$(CONFIG_AQUANTIA_PHY)	+= aquantia/
 ifdef CONFIG_AX88796B_RUST_PHY