From 812692db171c4a8451fb92953fc82dde5bede69c Mon Sep 17 00:00:00 2001
From: Lorenzo Bianconi <lorenzo@kernel.org>
Date: Wed, 27 Nov 2019 16:46:33 +0200
Subject: [PATCH] mt76: eeprom: add support for big endian eeprom partition

mt76x0e users reported some devices (e.g TP-Link Archer VR200v) have
been flashed with big endian radio partition. Add the possibility to
specify eeprom endianness using big-endian dts property and in case
covert eeprom data in little endian

Tested-by: Kevin Schmidt <kevin.patrick.schmidt@googlemail.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
 eeprom.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/eeprom.c b/eeprom.c
index 4847ed52..831e1e1b 100644
--- a/eeprom.c
+++ b/eeprom.c
@@ -64,6 +64,16 @@ mt76_get_of_eeprom(struct mt76_dev *dev, int len)
 		goto out_put_node;
 	}
 
+	if (of_property_read_bool(dev->dev->of_node, "big-endian")) {
+		u8 *data = (u8 *)dev->eeprom.data;
+		int i;
+
+		/* convert eeprom data in Little Endian */
+		for (i = 0; i < round_down(len, 2); i += 2)
+			put_unaligned_le16(get_unaligned_be16(&data[i]),
+					   &data[i]);
+	}
+
 out_put_node:
 	of_node_put(np);
 	return ret;