kernel-module-qualcomm: load specific firmware file per region

The country region is programmed in the OTP bits. Based on that value we need
to load the firmware file for the specific country region.

https://jira.digi.com/browse/DEL-2774

Signed-off-by: Isaac Hermida <isaac.hermida@digi.com>

meta-digi-arm/recipes-kernel/kernel-module-qualcomm/kernel-module-qualcomm/qualcomm-pre-up

@@ -17,7 +17,8 @@
 
 [ "${IFACE}" != "wlan0" ] && exit 0
 
-MACFILE="/lib/firmware/wlan/wlan_mac.bin"
+FIRMWARE_DIR="/lib/firmware"
+MACFILE="${FIRMWARE_DIR}/wlan/wlan_mac.bin"
 TMP_MACFILE="$(mktemp -t wlan_mac.XXXXXX)"
 
 # Read the MACs from DeviceTree. We can have up to four wireless interfaces
@@ -49,6 +50,31 @@ if ! cmp -s ${TMP_MACFILE} ${MACFILE}; then
 fi
 rm -f ${TMP_MACFILE}
 
+REGION_CODE="$(cat /proc/device-tree/digi,hwid,cert 2>/dev/null)"
+US_CODE="0x0"
+WW_CODE="0x1"
+JP_CODE="0x2"
+BDATA_LINK="${FIRMWARE_DIR}/bdwlan30.bin"
+# Create a symbolic link to the FW file for the specific country region.
+BDATA_SOURCE="${FIRMWARE_DIR}/bdwlan30_US.bin"
+case "${REGION_CODE}" in
+	${US_CODE})
+		logger -t qca6564 "Setting US wireless region";;
+	${WW_CODE}|${JP_CODE})
+		logger -t qca6564 "Setting WW (world wide) wireless region"
+		BDATA_SOURCE="${FIRMWARE_DIR}/bdwlan30_World.bin";;
+	"")
+		logger -t qca6564 "[WARN] region code not found, using US";;
+	*)
+		logger -t qca6564 "[WARN] Invalid region code, using US";;
+esac
+
+# We don't want to rewrite NAND every time we boot so only
+# change the link if it is wrong.
+if [ ! -e "${BDATA_LINK}" ] || ! cmp -s "${BDATA_LINK}" "${BDATA_SOURCE}"; then
+	ln -sf "${BDATA_SOURCE}" "${BDATA_LINK}"
+fi
+
 # Check the version of modprobe installed to compound the arguments.
 if readlink -f $(which modprobe) | grep -qs kmod; then
 	MODPROBE_ARGS="-i"