[PATCH v3 0/3] ASoC: mchp-pdmc: fix poc noises when starting capture

Mark Brown broonie at kernel.org
Tue Feb 28 10:00:41 PST 2023


On Tue, 28 Feb 2023 13:01:42 +0200, Claudiu Beznea wrote:
> To start capture on Microchip PDMC the enable bits for each supported
> microphone need to be set. After this bit is set the PDMC starts to
> receive data from microphones and it considers this data as valid data.
> Thus if microphones are not ready the PDMC captures anyway data from its
> lines. This data is interpreted by the human ear as poc noises.
> 
> To avoid this the following software workaround need to be applied when
> starting capture:
> 1/ enable PDMC channel
> 2/ wait 150ms
> 3/ execute 16 dummy reads from RHR
> 4/ clear interrupts
> 5/ enable interrupts
> 6/ enable DMA channel
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next

Thanks!

[1/3] ASoC: soc-pcm: add option to start DMA after DAI
      commit: 54fc4b72b630e1cb92a21140084c6852babbb234
[2/3] ASoC: dt-bindings: sama7g5-pdmc: add microchip,startup-delay-us binding
      commit: 143a2f011c4471511887807822d3fd71f25f5169
[3/3] ASoC: mchp-pdmc: fix poc noise at capture startup
      commit: c5682e2ba1327d08987a7cabc7b5b40bf3bc131f

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark




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