Re: [PATCH v2] ASoC: meson: aiu: fifo-spdif: soft reset the S/PDIF datapath on start/stop

[Ferass El Hafidi]

Hi Christian,

On Sat, 27 Jun 2026 12:50, Christian Hewitt <christianshewitt@xxxxxxxxx> wrote:
> The I2S FIFO soft-resets its fast domain on start (AIU_RST_SOFT bit 0 +
> AIU_I2S_SYNC read in aiu_fifo_i2s_trigger), mirroring the downstream
> vendor driver's audio_out_i2s_enable(). The S/PDIF FIFO has no equivalent:
> it only toggles the IEC958 DCU, so a stale datapath FIFO can be replayed,
> producing the "machine gun noise" buffer underrun - on start when switching
> outputs, and on stop when playback ends. The latter is audible on devices
> with an always-on S/PDIF-fed DAC (e.g. the ES7144 on the WeTek Play2).
>
> The vendor driver resets the IEC958 fast domain (AIU_RST_SOFT bit 2) on
> both enable and disable (audio_hw_958_enable), and when reconfiguring
> (audio_hw_958_reset clears AIU_958_DCU_FF_CTRL then resets). Do the same:
> reset before enabling the DCU on start, and after disabling it on stop.
>
> Fixes: 6ae9ca9ce986bf ("ASoC: meson: aiu: add i2s and spdif support")
> Signed-off-by: Christian Hewitt <christianshewitt@xxxxxxxxx>

You may have forgotten to add Martin's R-b here.

Best regards,
Ferass