How to set regulation domain in LWB/LWB5/LWB5+ with latest release 8.5.0.7 and later release in Linux platform?

Answer

(1) By option regdomain

/etc/modprobe.d/brcmfmac.conf

# Sample contents of a brcmfmac.conf file configured for operation in
#  the United States
options brcmfmac regdomain="US"

(2) By device tree

@mmc0 {
  #address-cells = <1>;
  #size-cells = <0>;
  bus-width = <4>;
  non-removable;

  brcmf: wifi@1 {
    reg = <1>;
    compatible = "brcm,bcm4329-fmac";
    laird,regdomain = "US";
  };
};