Re: [PATCH] net: phy: realtek: add support for RTL8366S Gigabit PHY

[Mark Mentovai <mark@mentovai.com>]

Simon Horman wrote:
> On Thu, Jul 25, 2024 at 01:05:19PM -0400, Mark Mentovai wrote:
>> The PHY built in to the Realtek RTL8366S switch controller was
>> previously supported by genphy_driver. This PHY does not implement MMD
>> operations. Since 9b01c885be36 (2023-02-13, in 6.3), MMD register reads
>> have been made during phy_probe to determine EEE support. For
>> genphy_driver, these reads are transformed into 802.3 annex 22D clause
>> 45-over-clause 22 mmd_phy_indirect operations that perform MII register
>> writes to MII_MMD_CTRL and MII_MMD_DATA. This overwrites those two MII
>> registers, which on this PHY are reserved and have another function,
>> rendering the PHY unusable while so configured.
>>
>> Proper support for this PHY is restored by providing a phy_driver that
>> declares MMD operations as unsupported by using the helper functions
>> provided for that purpose, while remaining otherwise identical to
>> genphy_driver.
>>
>> Fixes: 9b01c885be36 ("net: phy: c22: migrate to genphy_c45_write_eee_adv()")
>> Fixes: https://github.com/openwrt/openwrt/issues/15981
>
> nit: AFAIK, the line immediately above is not a correct use of the Fixes
>     tag. I think Link or Closes would be appropriate instead.
>
>> Link: https://github.com/openwrt/openwrt/issues/15739
>> Reported-by: Russell Senior <russell@personaltelco.net>
>> Signed-off-by: Mark Mentovai <mark@mentovai.com>
>
> Also, as a fix, this should be targeted at the net tree.
>
> 	Subject: [PATCH net] ...
>
> Please see https://docs.kernel.org/process/maintainer-netdev.html

Thanks for your feedback, Simon. I've sent an updated (v2) patch, now at 
https://lore.kernel.org/netdev/20240725204147.69730-1-mark@mentovai.com/.