Merge patch series "net: ksz9477: add support for KSZ GbE switches using SPI bus"

Merge patch series "net: ksz9477: add support for KSZ GbE switches using SPI bus"

Romain Naour <romain.naour@smile.fr> says:

We are using a custom board where an ethernet switch device KSZ9896 is
available. This family of devices can use several types of serial bus
as management interface: mdio, i2c or SPI. Due to board design
constraints and because we initially planned to use this device only
from Linux, the SPI bus was used.

Luckily we are using a recent enough u-boot release where KSZ9477
driver is available... but only for the i2c interface. Indeed, unlike
the kernel driver, the KSZ9477 driver doesn't use the regmap API to
access the underlying bus since the regmap API is limited to direct
memory access [1].

Until regmap API with bus support is available in U-boot, we introduced
struct ksz_phy_ops to store low-level ksz bus operations (I2C or SPI).

This series has been tested on the current master branch (after v2024.10
release).

[1] https://source.denx.de/u-boot/u-boot/-/blob/v2024.10-rc5/drivers/core/Kconfig?ref_type=tags#L188

Link: https://lore.kernel.org/r/20241008075435.1572727-1-romain.naour@smile.fr