[PATCH 1/2] arm64: dts: mediatek: mt7622: set PHY address of MT7531 switch to 0x1f

Florian Fainelli f.fainelli at gmail.com
Fri Mar 15 10:26:41 PDT 2024


On 3/14/24 05:20, Arınç ÜNAL via B4 Relay wrote:
> From: Arınç ÜNAL <arinc.unal at arinc9.com>
> 
> The MT7531 switch listens on PHY address 0x1f on an MDIO bus. I've got two
> findings that support this. There's no bootstrapping option to change the
> PHY address of the switch. The Linux driver hardcodes 0x1f as the PHY
> address of the switch. So the reg property on the device tree is currently
> ignored by the Linux driver.
> 
> Therefore, describe the correct PHY address on boards that have this
> switch.

Can we call it a pseudo PHY to use a similar terminology as what is done 
through drivers/net/dsa/{bcm_sf2,b53}*?

This is not a real PHY as in it has no actual transceiver/digital signal 
processing logic, this is a piece of logic that snoops for MDIO 
transactions at that specific address and lets you access the switch's 
internal register as if it was a MDIO device.

LGTM otherwise!
-- 
Florian




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