Re: [PATCH 1/2] ASoC: simple-card-utils: add ignore_zero_sysclk flag

[Sheetal .]

On 18-03-2026 04:32, Kuninori Morimoto wrote:
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>
>
> Hi
>
> > > Commit 2458adb8f92a ("SoC: simple-card-utils: set 0Hz to
> > > sysclk when shutdown") updated the simple-card-util driver to
> > > send 0Hz frequency requests during stream shutdown, which can
> > > request frequencies lower than a platform may support.
> >
> > > Add ignore_zero_sysclk flag to struct simple_util_priv to allow drivers
> > > to ignore these 0Hz sysclk requests when they would result in a clock
> > > frequency below the hardware's minimum allowed rate.
> >
> > If the driver simply can't tolerate disabling the sysclk it seems like
> > it would be easier to just have the driver directly ignore attempts to
> > do so rather than adding this flag which the driver has to set only to
> > get it passed in?
>
> Agree.
> I think this commit can help you ?
>
>          1e1a2ef95b571825ca9c0113f6bef51e9cec98b0
>          ("ASoC: da7213: Avoid setting PLL when closing audio stream")
>
> Thank you for your help !!


Thank you for the feedback and the da7213 reference.

The concern with the per-codec approach is that this affects any codec 
with a set_dai_sysclk that forwards the frequency to clk_set_rate(). 
Since any codec can be connected to Tegra platforms, and MCLK is 
provided by the SoC to external codecs, when clk_set_rate(..., 0) 
reaches the BPMP firmware, it raises a fault for rates below the 
hardware minimum. Fixing this per-codec would require individual patches 
for each.


> Best regards
> ---
> Kuninori Morimoto