[Letux-kernel] [PATCH 0/8] Get sound playback working on the Pandora again

[H. Nikolaus Schaller]

Hi Grond,

> Am 31.12.2021 um 01:41 schrieb Grond <grond66 at riseup.net>:
> 
> Hello all.
> 
> A somewhat belated Christmas gift for those using the letux kernel on
> their Pandoras: I have managed to get sound playback to work again. I
> will be replying to this mail with the actual patches.
> 
> Note that these changes only fix playback. Recording sound does not
> currently work for as yet unknown reasons. However, given the (mind
> boggling) number of ALSA kcontrols exposed by the TWL4030's sound
> capture codec, it is likely that there is just a switch that is turned
> off somewhere.
> 
> If whoever is responsible for merging these sorts of things could tell
> me what to do next (feedback, etc), that would be great.
> 
> Thanks,
> 	--Grond
> 
> Grond (8):
>  arm: dts: omap3pandora: Don't use DMA channels for unused SPI masters
>  ASoC: pcm1773-codec: write a driver for the PCM1773 chip from TI
>  arm: dts: omap3pandora: Add device node for PCM1773 codec
>  ASoC: twl4030-codec: Allow setting APLL rate through the .set_sysclk()
>    interface
>  regulator: twl: Expose the TWL4030's REGEN signal as a regulator
>  arm: dts: omap3pandora: Populate DT data for the TWL4030's REGEN
>    regulator
>  ASoC: omap3pandora: Rewrite sound card driver as a platform driver
>  arm: dts: omap3pandora: Create new DT node for the sound card driver
> 
> .../bindings/regulator/twl-regulator.txt      |  12 +
> arch/arm/boot/dts/omap3-pandora-common.dtsi   |  39 ++
> arch/arm/boot/dts/twl4030.dtsi                |  14 +
> drivers/regulator/twl-regulator.c             |  51 +++
> include/linux/mfd/twl.h                       |   3 +
> include/linux/mfd/twl4030-audio.h             |   3 +
> sound/soc/codecs/Kconfig                      |   5 +
> sound/soc/codecs/Makefile                     |   2 +
> sound/soc/codecs/pcm1773.c                    | 174 +++++++
> sound/soc/codecs/twl4030.c                    | 138 ++++--
> sound/soc/ti/omap3pandora.c                   | 430 +++++++++++++-----
> 11 files changed, 725 insertions(+), 146 deletions(-)
> create mode 100644 sound/soc/codecs/pcm1773.c

That is great! I have added it to the latest letux tree and after configuring
the pcm1773 I can see a sound card and aplay is even doing something.

But I haven't tested much. A first observation was that loudness is changing
but it may be the simple audio file I had tried.

Anyways I want to add it to the next letux-5.16 release which I think will
come tomorrow. And backport to LTS kernels 5.15.y, 5.10.y and 5.4.y.

BR and thanks and a (late) happy new year!

Nikolaus