Hi Arnaud
Thank you for checking/testing driver
In our sound card (described here: https://github.com/STMicroelectronics/linux/blob/v4.19-stm32mp/arch/arm/boot...)
We declare a normal sound card using the WM8994 codec:
Playback: CPU-DAI (SAI2a)-> CODEC-DAI/port0 Record: CPU-DAI (SAI2B)<- CODEC-DAI/port1 ...
The WM8994 codec is declared with 2 ports as it supports 2 interfaces.
When we probe the sound card we are detecting a wrong dai link type because the condition if (of_get_child_count(codec_port) > 1) return true. The dai link is detected as DPCM instead of the expected normal link.
It seems difficult to use WM8994 on my test environment. And I tried to add 2 ports on my sound codec driver/DT, but I can't reproduce your issue. But, I want to solve your issue.
In my understanding, in your case, cpu/codec will be below.
for Playback cpu_ep = sai2a_endpoint codec_ep = wm8994_tx_endpoint codec_port = wm8994_tx_port
for Record cpu_ep = sai2b_endpoint codec_ep = wm8994_rx_endpoint codec_port = wm8994_rx_port
Please could you elaborate a little bit on this criteria for the normal/DPCM selection?
What is you feeling about this limitation. Do you see a way to refine the condition to allow normal sound card with multi-port codecs. Or do we have to migrate our sound card to DPCM.
If it was DPCM, 1 port is connected from multiple "endpoint". So, audio-graph-card is checking if it was "multi-endpoint" or not. "multi-port" is not related to this judgment.
And in your case, if my understanding was correct, wm8994_tx/rx only have single-endpoint. so, if (of_get_child_count(codec_port) > 1) return true is a little bit strange for me. Can you check what is this codec_port ? I think you can use printk("%pOF\n", codec_port) for it.