09:15 <jbrunet> phh: https://dl.khadas.com/products/vim3l/datasheet/s905d3_datasheet_0.2_wesion.pdf - Check page 840 - table 9-32. PDM input is "IN 4" on this SoC ... assuming your board is indeed an SEI610 with an S905D/X3

09:15 <jbrunet> It also shows up here : https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/amlogic/meson-sm1-sei610.dts?h=v6.7-rc4#n225

09:15 <jbrunet> The error mentioned may happen for several reasons, including incorrect routing. PDM cannot provide S16_LE. `hw_params` will throw a similar error because params setup fails in ASoC.

09:15 <jbrunet> Also I'd recommend setting a rate. PDM won't come up with one on its own. Something like: `amixer sset "TODDR_A SRC SEL" "IN 4"` then `arecord -D hw:0,3 -f S32_LE -c 2 -r48000`

09:15 <jbrunet> `hw:0,5` is most likely TODDR_C. Check `/proc/asound/pcm` against DT. if you tried playing with `TODDR_A SRC SEL`, it did not change anything for you. Try `hw:0,3`

09:28 <phh> thanks for the datasheet and the mention of IN 4 in dts, I indeed failed to notice that. I did try setting 48kHz rate (and other values), sorry for not mentioning that. I'm pretty sure I did try hw:0,3 with TODDR_A set to IN 4, but I'll try again. It's possible I didn't try that whole combination, thanks

09:39 <phh> well, it does work

09:39 <phh> thanks

09:41 <jbrunet> :) There is a lot of knobs to adjust indeed. That's how the HW is ...

09:42 <f_> UCM profiles would be helpful there

09:44 <f_> As for DRAM..I'll probably have to reimplement dual-channel mode..

09:48 <jbrunet> UCM works when the use case is known.

09:48 <jbrunet> Out of that, there is no "one size fits all"

09:48 <jbrunet> That's not entirely obvious on SBCs, especially if it is used out the basic desktop/HDMI UI scenario.

09:48 <jbrunet> Even which TODDR you pick depends on what you intend to do. TODDR_A usually has a bigger FIFO more suited for high throughput capture than the other

09:58 <phh> the thing I don't really understand, is why does the dts doesn't exclusively declare "TODDR_A IN 4" and nothing else? What's the point of exposing 0 and 1? And the other thing is, dts only exposes in 0/1/4, why does the mixer expose them all? and then, there should be some defaults in the dts? ofc ucm is needed for changing usecases/routing, but that can be static

09:58 <phh> that being said I don't understand why that dts has tdmin_a/tdmin_b

10:10 <jbrunet> What you see through alsamixer/amixer is the kcontrol of the mux: This FIFO does have 16 inputs: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/sound/soc/meson/axg-toddr.c?h=v6.7-rc4#n267

10:10 <jbrunet> Depending on the SoC, some inputs are connected, some are not.

10:10 <jbrunet> To help confuse people a bit, the routing table in DT mixes routes internal to the SoC (between the internal components) and external (route to you PDM mics for example) ... and you can only add route for component which are instantiated in the card. Can't put the route for TDM_C if the card is not using it. That why you have this big (ugly) routing table on each card. All cards are differents.

10:10 <jbrunet> I'm working on something to split the internal and external routing in DT so that we can add, once a for all, the internal routes somewhere and only worry about the external one in the board dts.

10:10 <jbrunet> That takes time

10:11 <phh> yeah yeah, I know this has forever been like this on all platforms on Linux, so hard to blame anyone

10:12 <jbrunet> tdmin_a/tdmin_b may be used for Playback loopback on this device

10:18 <phh> ok

10:18 <jbrunet> > there should be some defaults in the dts

10:18 <jbrunet> - Make your configuration as you want it

10:18 <jbrunet> Best way to have sane default is

10:18 <jbrunet> No DT is meant for configuration, and again, sane default depends on what you want to do.

10:18 <jbrunet> - use `alsactl store/restore` save and restore it on boot

10:18 <jbrunet> not meant to :)

10:19 <f_> jbrunet: yeah

10:20 <phh> DT has chosen {} which is literally configuration. It also has CMA sizes which are opiniated configurations

10:33 <f_> (said 'yeah' to >That's not entirely obvious on SBCs, especially...)

11:18 <f_> Set-top box looks like it's dying?

11:20 <f_> Or did I worry for nothing?

11:21 <f_> Was booting BL2 (from USB) and in pmOS screen suddently became garbled. I just rebooted