MAX98090 was a reference codec in Nvidia Tegra chipset.
You can find machine code for Nvidia chipset from below link.
https://github.com/torvalds/linux/blob/master/sound/soc/tegra/tegra_max98090.c
Some more in the Kernel v4.14.98Mediatek
https://elixir.bootlin.com/linux/v4.14.98/source/sound/soc/mediatek/mt8173/mt8173-max98090.c
Intel
https://elixir.bootlin.com/linux/v4.14.98/source/sound/soc/intel/boards/cht_bsw_max98090_ti.c
Samsung Exynos
https://github.com/hardkernel/linux/blob/odroid-3.0.y/sound/soc/samsung/odroid_max98090.c
Rockchip
https://elixir.bootlin.com/linux/v4.14.98/source/sound/soc/rockchip/rockchip_max98090.c