linux-kernel - Re: [PATCH v3] ASoC: fsl_sai: Force a software reset when starting in consumer mode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <fe9956b2-4d71-4a57-ab70-6ff64c4525cf@app.fastmail.com>
Date: Thu, 26 Jun 2025 08:27:58 -0400
From: "Arun Raghavan" <arun@...nraghavan.net>
To: "Fabio Estevam" <festevam@...il.com>
Cc: "Shengjiu Wang" <shengjiu.wang@...il.com>,
 "Xiubo Li" <Xiubo.Lee@...il.com>, "Nicolin Chen" <nicoleotsuka@...il.com>,
 "Liam Girdwood" <lgirdwood@...il.com>, "Mark Brown" <broonie@...nel.org>,
 "Jaroslav Kysela" <perex@...ex.cz>, "Takashi Iwai" <tiwai@...e.com>,
 "Pieterjan Camerlynck" <p.camerlynck@...evic.com>,
 linux-sound@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
 linux-kernel@...r.kernel.org, "Arun Raghavan" <arun@...mptotic.io>
Subject: Re: [PATCH v3] ASoC: fsl_sai: Force a software reset when starting in consumer
 mode

On Thu, 26 Jun 2025, at 7:58 AM, Fabio Estevam wrote:
> Hi Arun,
>
> On Thu, Jun 26, 2025 at 8:52 AM Arun Raghavan
> <arun@...nraghavan.net> wrote:
>>
>> From: Arun Raghavan <arun@...mptotic.io>
>>
>> On an imx8mm platform with an external clock provider, when running
>> the receiver (arecord) and triggering an xrun with xrun_injection, we
>> see a channel swap/offset. This happens sometimes when running only
>> the receiver, but occurs reliably if a transmitter (aplay) is also
>> concurrently running.
>>
>> It seems that the SAI loses track of frame sync during the trigger
>> stop -> trigger start cycle that occurs during an xrun. Doing just a
>> FIFO reset in this case does not suffice, and only a software reset
>> seems to get it back on track.
>>
>> This looks like the same h/w bug that is already handled for the
>> producer case, so we now do the reset unconditionally on config
>> disable.
>>
>> Signed-off-by: Arun Raghavan <arun@...mptotic.io> Reported-by:
>> Pieterjan Camerlynck <p.camerlynck@...evic.com>
>
> What about adding a Fixes tag and Cc stable so that it gets backported
> to the stable trees?

Sure! Will send in a v4 with both of these.

The commit that added the initial fix (3e3f8bd56955 ("ASoC: fsl_sai: fix
no frame clk in master mode")) refers to an errata, but I could find
anything in a couple of imx8* errata I checked.

I was wondering if there's any public documentation of this that I can
refer (and link) to?

Cheers,
Arun