Other Parts Discussed in Thread: PCA9535
1. am 335x processor sdk 9.1 or 9.3 cross-compile tool
why choose to use external-toolchain-dir/arm-gnu-toolchain-11.3.rel1-x86_64-arm-none-linux-gnueabihf/bin/arm-none-linux-gnueabihf- instead of built-in one (just the built-in one has compilation issues ?);
In sdk9.3 of the AM57 processor, we use the built-in one, if so, different processors will face the problem of compiling the toolchain
2. The gpio num is different the same config in dts between sdk 6.3 and sdk 9.1/9.3
such as in sdk 6.3: 
while use sdk9.1 ：
The gpio numbers of the I2C external expansion IO PCA9535 in sdk 6.3 have changed from 496-511 to 2026-2041 in SDK 9.1 ，Can we keep it consistent with the old sdk through simple modifications
