If someone can show me a method to enable device tree overlays on-the-fly on mainline Linux 6.5.y, I am open to try it. I have however never seen such, despite for a very short time on Raspberry Pi with their vendor kernel/bootloader and "dtoverlay" command, which worked with only a very small number of their overlays, while in most cases it just caused kernel errors and did not enable the intended functionality. From that point on I was pretty sure that there is no reliable way to enable kernel device tree overlays on-the-fly, but I am open to be proven wrong.
In the meantime, even extlinux has support for (not on-the-fly) device tree overlays with fdtoverlay setting, so theoretically we could add some. Our U-Boot might be too old, as it is still a fork based on 2022.10, but I should be able to switch to mainline U-Boot, now that it supports adding (the sadly needed) SPL and DDR blobs properly.
But, it might be easier to enable I2S/SPI/... interfaces just OOTB, as long as they do not collide and the GPIO pins do not have conflicting uses.
In the meantime, even extlinux has support for (not on-the-fly) device tree overlays with fdtoverlay setting, so theoretically we could add some. Our U-Boot might be too old, as it is still a fork based on 2022.10, but I should be able to switch to mainline U-Boot, now that it supports adding (the sadly needed) SPL and DDR blobs properly.
But, it might be easier to enable I2S/SPI/... interfaces just OOTB, as long as they do not collide and the GPIO pins do not have conflicting uses.