[RFC PATCH net-next v3 11/15] net: dsa: mt7530: skip locking if MDIO bus isn't present

[Andrew Lunn]

On Wed, Mar 29, 2023 at 04:59:47PM +0100, Daniel Golle wrote:
> As MT7530 and MT7531 internally use 32-bit wide registers, each access
> to any register of the switch requires several operations on the MDIO
> bus. Hence if there is congruent access, e.g. due to PCS or PHY
> polling, this can mess up and interfere with another ongoing register
> access sequence.
> 
> However, the MDIO bus mutex is only relevant for MDIO-connected
> switches. Prepare switches which have there registers directly mapped
> into the SoCs register space via MMIO which do not require such
> locking. There we can simply use regmap's default locking mechanism.
> 
> Hence guard mutex operations to only be performed in case of MDIO
> connected switches.
> 
> Signed-off-by: Daniel Golle <daniel at makrotopia.org>

Reviewed-by: Andrew Lunn <andrew at lunn.ch>

    Andrew