spi-bridge with recent OpenWrt

I'm involved in project which uses the WrtNode2R as a data-hub for renewable energy application based on recent LEDE/OpenWrt. I did my best to fix things so I can use Kernel 4.14:
One remaining issue is spi-bridge communication with RTThread. I managed to get all packages from https://github.com/WRTnode/openwrt-packages.git built with only very little modifications (removing references to missing error.h header). However, spi-bridge doesn't work when using OpenWrt's spi-mt7621.c driver:
root@OpenWrt:/# spi-bridge status
spi bridge send cmd error.
spi bridge read status error.
When using the stock OpenWrt ChaosCalmer 15.05 which came on the board, it works
root@OpenWrt:/# spi-bridge status

Unfortunately, the repository on github only contains a binary blob
which cannot be used with recent kernels...

Please share the modifications made to ralink_spi_bbu driver or give me a hint what is needed as otherwise I'll have to revert to bit-banging SPI which is extremely slow :/

xzmu - 10w


this driver use bit-banging SPI driver for CS1,it's slow too



xzmu: so the m25p80 is used with ramips-spi in hardware as and for using the stm32 the direct does bit-banging... obviously pinctrl mapping in sysctrl need to be changed for that as well, but yes, it's as good as it can get on MT76x8 hardware...