lantiq: fritz_cal_extract with reverse option for AVM FritzBox 7430

This implementation of fritz_cal_extract can also retrieve firmware
data stored in reverse byte order, as found in the AVM 7430 device.

This is done by intermediate storage in a buffer presumably large enough
to hold the complete data set. Currently, this buffer size is 128kB + 1kB
(some extra space for skipped data).

In the usual case of "forward" data, this implementation should behave
like the original implementation in all common cases. limit [-l] will
determine the amount of data read and size of buffer allocated.

However, if you are reading reversed data or didn't set a limit, the buffer
may be too small to hold all data. In this case, you can choose a higher
limit [-l] to enforce a sufficient buffer size.

Signed-off-by: Dustin Gathmann <[email protected]>

target/linux/lantiq/xrx200/base-files/etc/hotplug.d/firmware/12-ath9k-eeprom

@@ -22,11 +22,14 @@ case "$FIRMWARE" in
 			avm,fritz7360sl)
 				caldata_extract "urlader" 0x985 0x1000
 				;;
-			avm,fritz7412|\
-			avm,fritz7430)
+			avm,fritz7412)
 				/usr/bin/fritz_cal_extract -i 1 -s 0x1e000 -e 0x207 -l 5120 -o /lib/firmware/$FIRMWARE $(find_mtd_chardev "urlader") || \
 				/usr/bin/fritz_cal_extract -i 1 -s 0x1e800 -e 0x207 -l 5120 -o /lib/firmware/$FIRMWARE $(find_mtd_chardev "urlader")
 				;;
+			avm,fritz7430)
+				/usr/bin/fritz_cal_extract -r -i 4 -s 0x1e000 -e 0x207 -l 5120 -o /lib/firmware/$FIRMWARE $(find_mtd_chardev "urlader") || \
+				/usr/bin/fritz_cal_extract -r -i 4 -s 0x1e800 -e 0x207 -l 5120 -o /lib/firmware/$FIRMWARE $(find_mtd_chardev "urlader")
+				;;
 			bt,homehub-v5a)
 				caldata_extract_ubi "caldata" 0x1000 0x1000
 				ath9k_patch_mac_crc $(macaddr_add $(mtd_get_mac_binary_ubi caldata 0x110c) 2) 0x10c