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Date:   Thu, 17 Aug 2023 16:20:31 -0700 (PDT)
From:   Wenli Looi <wlooi@ucalgary.ca>
To:     =?ISO-8859-15?Q?Toke_H=F8iland-J=F8rgensen?= <toke@toke.dk>
cc:     linux-wireless@vger.kernel.org, Kalle Valo <kvalo@kernel.org>,
        Felix Fietkau <nbd@nbd.name>
Subject: Re: [PATCH v3 00/11] wifi: ath9k: add support for QCN550x
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> Did you do any regression tests on other types of ar9300 hardware to
> ensure these patches don't negatively affect existing systems?

I've tried this new driver on a QCA9558 SoC (Netgear EX7300v1) which is
another ar9300 device, and the access point performance didn't seem to
be affected. I could do more detailed tests if desired.

> 
> >   Revert "ath9k_hw: fall back to OTP ROM when platform data has no valid
> >     eeprom data"
> 
> This revert seems a bit dodgy; the commit message states "Users
> currently relying on this silent fallback will need to stop providing
> invalid EEPROM data to the driver." - which kinda sounds like a
> kernel-to-userspace regression to me? Do any such systems actually
> exist?

I'm not sure if such systems exist. They shouldn't for the SoC devices
like QCA9558, because i don't think they support EEPROM at all. It's
possible that they exist for pcie devices, but I expect the vast
majority of users would not be overriding the eeprom. Arguably, if they
are setting qca,no-eeprom and this silent fallback ignores and uses
eeprom anyways, that could be considered a bug that is fixed here? We
could also choose to keep the fallback except for this new device.

I cc'ed Felix Fietkau here. If you remember the context for this change,
that would probably be helpful.