LXR linux/drivers/net/wireless/mediatek/mt76/eeprom.c

   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