Subject: Re: [PATCH 1/3] ALSA: hda/tegra: Skip reset on BPMP devices
To:     Jon Hunter <jonathanh@nvidia.com>,
        Sameer Pujar <spujar@nvidia.com>, tiwai@suse.com,
        broonie@kernel.org, lgirdwood@gmail.com, robh+dt@kernel.org,
        thierry.reding@gmail.com, perex@perex.cz
Cc:     alsa-devel@alsa-project.org, devicetree@vger.kernel.org,
        linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org
References: <1638858770-22594-1-git-send-email-spujar@nvidia.com>
 <1638858770-22594-2-git-send-email-spujar@nvidia.com>
 <7742adae-cdbe-a9ea-2cef-f63363298d73@gmail.com>
 <2f29f787-7c77-a56e-3b90-0fc452fd1c88@gmail.com>
 <9c21aa0d-b7e6-17b8-cd1a-f12a2b2a1a57@gmail.com>
 <5e50e8a1-5436-b543-f15d-50c5089304e3@nvidia.com>
From:   Dmitry Osipenko <digetx@gmail.com>
Message-ID: <9da3de11-b6c5-b2ac-f4cf-e14c73ec134a@gmail.com>
Date:   Tue, 7 Dec 2021 14:57:54 +0300
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07.12.2021 14:02, Jon Hunter пишет:
> 
> On 07/12/2021 10:58, Dmitry Osipenko wrote:
>> 07.12.2021 13:44, Dmitry Osipenko пишет:
>>> 07.12.2021 13:22, Dmitry Osipenko пишет:
>>>> 07.12.2021 09:32, Sameer Pujar пишет:
>>>>> HDA regression is recently reported on Tegra194 based platforms.
>>>>> This happens because "hda2codec_2x" reset does not really exist
>>>>> in Tegra194 and it causes probe failure. All the HDA based audio
>>>>> tests fail at the moment. This underlying issue is exposed by
>>>>> commit c045ceb5a145 ("reset: tegra-bpmp: Handle errors in BPMP
>>>>> response") which now checks return code of BPMP command response.
>>
>> I see that this BPMP commit already has been reverted. There is no
>> problem in this hda_tegra driver at all.
> 
> That is temporary until this fix is merged and then we will revert the
> revert.

It's the device-tree that is broken, not the driver. If you don't care
about broken HDMI audio using outdated dtb, then there is nothing to fix
in the code.

Otherwise, the fix is to skip the non-existent reset.

You could add workaround to the BPMP reset driver by making it always
return success for TEGRA194_RESET_HDA2CODEC_2X invocation instead of
making the FW call for that reset.