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);
123