Subject: Re: wifi: mt76: mt7915e: mt7916 5GHz and 6GHz stopped working
To:     Florian Schmidt <florian@fls.name>,
        "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>
References: <c7fc198f2a4ed9c1345a05c0397a9fc5@mail.infomaniak.com>
From:   Ben Greear <greearb@candelatech.com>
Organization: Candela Technologies
Message-ID: <519290aa-3b88-2c21-7ca3-10186d9e807a@candelatech.com>
Date:   Mon, 23 Jan 2023 06:43:08 -0800
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On 1/23/23 5:32 AM, Florian Schmidt wrote:
> Hi all,
> 
> Using current firmware and kernel 6.1 (or 6.2-rc4 from wireless-testing), the 5 and 6GHz stopped working on MT7916  (from AsiaRF). It used to work with older firmware and kernel.
> 
> As a workaround, reverting to the older firmware seems to work. I can also get the 5GHz (but not the 6GHz!) to work building the driver using the workaround described on this dd-wrt bug report: https://github.com/openwrt/mt76/issues/720
> 
> How can I be of any assist investigating and fixing this issue?
> 
> Thanks,
> Florian
> 

We have a patch to hack the driver to allow one or the other with new
firmware.  Can post a version for 5.19 kernel soon, and we'll rebase on
something newer at some point soon.

Looks like root cause is that the mtk firmware added restrictions and cannot
be made to properly calibrate on both bands without a reboot.

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com