Atheros Country Code ART bypass passing a custom Country Name when loading the driver (e.g.: insmod ath cn=AU)

regd_diff.c

char *user_country_name = "";                              // [MOD]
module_param_named(cn, user_country_name, charp, S_IRUGO); // [MOD]
MODULE_PARM_DESC(cn, "Country Name");                      // [MOD]

static int __ath_regd_init(struct ath_regulatory *reg)
{
	struct country_code_to_enum_rd *country = NULL;
	u16 regdmn;

	if (!reg)
		return -EINVAL;

	ath_regd_sanitize(reg);

	printk(KERN_DEBUG "ath: EEPROM regdomain: 0x%0x\n", reg->current_rd);

	if (!ath_regd_is_eeprom_valid(reg)) {
		pr_err("Invalid EEPROM contents\n");
		return -EINVAL;
	}

	regdmn = ath_regd_get_eepromRD(reg);
	reg->country_code = ath_regd_find_country_by_name(user_country_name); // [MOD]
	if (reg->country_code != (u16) -1)                                    // [MOD]
	    printk(KERN_DEBUG "ath: User Override Country Code\n");           // [MOD]
	else                                                                  // [MOD]
  	    reg->country_code = ath_regd_get_default_country(regdmn);

	if (reg->country_code == CTRY_DEFAULT &&
	    regdmn == CTRY_DEFAULT) {
		printk(KERN_DEBUG "ath: EEPROM indicates default "
		       "country code should be used\n");
		reg->country_code = CTRY_UNITED_STATES;
	}
  
// [...]

LEDE instruction:

1. Clone LEDE project
   git clone https://github.com/lede-project/source.git
cd source

2. Build for your target
   make menuconfig (select your target)
   make package/kernel/mac80211/compile

3. Patch the driver with my diff
   You have to edit __ath_regd_init function in this file:
   build_dir/target-[ARCH]/linux-ar71xx_generic/backports-[VER]/drivers/net/wireless/ath/regd.c
   (Add lines with // [MOD] comment)

4. Build and flash the firmware
   Build the firmware
   make -j9
   (Where 9 is your cpu's threads number + 1)
   Then flash the router
   On PC: nc -l -p 1234 -q 0 < bin/targets/ar71xx/generic/lede-ar71xx-generic-[MODEL]-squashfs-sysupgrade.bin
   On router: nc 192.168.1.X 1234 > /tmp/fw.bin && sysupgrade /tmp/fw.bin

5. Add driver parameter
   After the router reboot, create the file /etc/modules.d/ath
   echo "ath cn=AU" > /etc/modules.d/ath
   So when LEDE starts up, the ath module will be loaded with cn (Country Name) parameter.

6. Check the Mod
   reboot the router and check log messages:
   dmesg | grep ath
   You should see

ath: EEPROM regdomain: 0x0
ath: User Override Country Code
ath: doing EEPROM country->regdmn map search
ath: country maps to regdmn code: 0x21
ath: Country alpha2 being used: AU
ath: Regpair used: 0x21

7. Check Reg Domain
   You can check the reg domain
   iw reg get
   and you should see

global
country AU: DFS-ETSI

phy#0
country AU: DFS-ETSI