1// SPDX-License-Identifier: ISC
  2/*
  3 * Copyright (C) 2016 Felix Fietkau <nbd@nbd.name>
  4 */
  5#include <linux/of.h>
  6#include <linux/of_net.h>
  7#include <linux/mtd/mtd.h>
  8#include <linux/mtd/partitions.h>
  9#include <linux/etherdevice.h>
 10#include "mt76.h"
 11
 12static int
 13mt76_get_of_eeprom(struct mt76_dev *dev, int len)
 14{
 15#if defined(CONFIG_OF) && defined(CONFIG_MTD)
 16	struct device_node *np = dev->dev->of_node;
 17	struct mtd_info *mtd;
 18	const __be32 *list;
 19	const char *part;
 20	phandle phandle;
 21	int offset = 0;
 22	int size;
 23	size_t retlen;
 24	int ret;
 25
 26	if (!np)
 27		return -ENOENT;
 28
 29	list = of_get_property(np, "mediatek,mtd-eeprom", &size);
 30	if (!list)
 31		return -ENOENT;
 32
 33	phandle = be32_to_cpup(list++);
 34	if (!phandle)
 35		return -ENOENT;
 36
 37	np = of_find_node_by_phandle(phandle);
 38	if (!np)
 39		return -EINVAL;
 40
 41	part = of_get_property(np, "label", NULL);
 42	if (!part)
 43		part = np->name;
 44
 45	mtd = get_mtd_device_nm(part);
 46	if (IS_ERR(mtd)) {
 47		ret =  PTR_ERR(mtd);
 48		goto out_put_node;
 49	}
 50
 51	if (size <= sizeof(*list)) {
 52		ret = -EINVAL;
 53		goto out_put_node;
 54	}
 55
 56	offset = be32_to_cpup(list);
 57	ret = mtd_read(mtd, offset, len, &retlen, dev->eeprom.data);
 58	put_mtd_device(mtd);
 59	if (ret)
 60		goto out_put_node;
 61
 62	if (retlen < len) {
 63		ret = -EINVAL;
 64		goto out_put_node;
 65	}
 66
 67	if (of_property_read_bool(dev->dev->of_node, "big-endian")) {
 68		u8 *data = (u8 *)dev->eeprom.data;
 69		int i;
 70
 71		/* convert eeprom data in Little Endian */
 72		for (i = 0; i < round_down(len, 2); i += 2)
 73			put_unaligned_le16(get_unaligned_be16(&data[i]),
 74					   &data[i]);
 75	}
 76
 77#ifdef CONFIG_NL80211_TESTMODE
 78	dev->test.mtd_name = devm_kstrdup(dev->dev, part, GFP_KERNEL);
 79	dev->test.mtd_offset = offset;
 80#endif
 81
 82out_put_node:
 83	of_node_put(np);
 84	return ret;
 85#else
 86	return -ENOENT;
 87#endif
 88}
 89
 90void
 91mt76_eeprom_override(struct mt76_dev *dev)
 92{
 93#ifdef CONFIG_OF
 94	struct device_node *np = dev->dev->of_node;
 95	const u8 *mac = NULL;
 96
 97	if (np)
 98		mac = of_get_mac_address(np);
 99	if (!IS_ERR_OR_NULL(mac))
100		ether_addr_copy(dev->macaddr, mac);
101#endif
102
103	if (!is_valid_ether_addr(dev->macaddr)) {
104		eth_random_addr(dev->macaddr);
105		dev_info(dev->dev,
106			 "Invalid MAC address, using random address %pM\n",
107			 dev->macaddr);
108	}
109}
110EXPORT_SYMBOL_GPL(mt76_eeprom_override);
111
112int
113mt76_eeprom_init(struct mt76_dev *dev, int len)
114{
115	dev->eeprom.size = len;
116	dev->eeprom.data = devm_kzalloc(dev->dev, len, GFP_KERNEL);
117	if (!dev->eeprom.data)
118		return -ENOMEM;
119
120	return !mt76_get_of_eeprom(dev, len);
121}
122EXPORT_SYMBOL_GPL(mt76_eeprom_init);