Re: [PATCH] net: dsa: add return value check of genphy_read_status()

From: Alexandra Diupina
Date: Thu Mar 21 2024 - 08:07:26 EST




21/03/24 02:48, Florian Fainelli пишет:


On 15/03/2024 03:25, Александра Дюпина wrote:
Hello, Andrew!

(please do not top-post)


The dsa_register_switch() function is used in various DSA
drivers (in probe function), so it is necessary to check all
possible errors. If the return value (may be an error code)
of genphy_read_status() is not checked in
dsa_shared_port_fixed_link_register_of(), a possible error
in dsa_register_switch() may be missed.

This is not a path that will fail, because the fixed PHY emulation layer is not a real piece of hardware, therefore no MDIO read could really cause a problem here. I don't have a strong opinion however if you want to propagate it properly.

Hi, Florian!
I would like to make sure that I have understood you correctly. Checking the return value of genphy_read_status() in dsa_shared_port_fixed_link_register_of() is not needed because dsa_shared_port_fixed_link_register_of() is called if of_phy_is_fixed_link()==true (this means that the PHY emulation layer is used, link is registered by of_phy_register_fixed_link() without errors and therefore there cannot be an error in genphy_read_status()). Right?