root/drivers/net/wireless/mediatek/mt76/eeprom.c
// SPDX-License-Identifier: BSD-3-Clause-Clear
/*
 * Copyright (C) 2016 Felix Fietkau <nbd@nbd.name>
 */
#include <linux/of.h>
#include <linux/of_net.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/nvmem-consumer.h>
#include <linux/etherdevice.h>
#include "mt76.h"

static int mt76_get_of_eeprom_data(struct mt76_dev *dev, void *eep, int len)
{
        struct device_node *np = dev->dev->of_node;
        const void *data;
        int size;

        data = of_get_property(np, "mediatek,eeprom-data", &size);
        if (!data)
                return -ENOENT;

        if (size > len)
                return -EINVAL;

        memcpy(eep, data, size);

        return 0;
}

int mt76_get_of_data_from_mtd(struct mt76_dev *dev, void *eep, int offset, int len)
{
#ifdef CONFIG_MTD
        struct device_node *np = dev->dev->of_node;
        struct mtd_info *mtd;
        const __be32 *list;
        const char *part;
        phandle phandle;
        size_t retlen;
        int size;
        int ret;

        list = of_get_property(np, "mediatek,mtd-eeprom", &size);
        if (!list)
                return -ENOENT;

        phandle = be32_to_cpup(list++);
        if (!phandle)
                return -ENOENT;

        np = of_find_node_by_phandle(phandle);
        if (!np)
                return -EINVAL;

        part = of_get_property(np, "label", NULL);
        if (!part)
                part = np->name;

        mtd = get_mtd_device_nm(part);
        if (IS_ERR(mtd)) {
                ret =  PTR_ERR(mtd);
                goto out_put_node;
        }

        if (size <= sizeof(*list)) {
                ret = -EINVAL;
                goto out_put_node;
        }

        offset += be32_to_cpup(list);
        ret = mtd_read(mtd, offset, len, &retlen, eep);
        put_mtd_device(mtd);
        if (mtd_is_bitflip(ret))
                ret = 0;
        if (ret) {
                dev_err(dev->dev, "reading EEPROM from mtd %s failed: %i\n",
                        part, ret);
                goto out_put_node;
        }

        if (retlen < len) {
                ret = -EINVAL;
                goto out_put_node;
        }

        if (of_property_read_bool(dev->dev->of_node, "big-endian")) {
                u8 *data = (u8 *)eep;
                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]);
        }

#ifdef CONFIG_NL80211_TESTMODE
        dev->test_mtd.name = devm_kstrdup(dev->dev, part, GFP_KERNEL);
        if (!dev->test_mtd.name) {
                ret = -ENOMEM;
                goto out_put_node;
        }
        dev->test_mtd.offset = offset;
#endif

out_put_node:
        of_node_put(np);
        return ret;
#else
        return -ENOENT;
#endif
}
EXPORT_SYMBOL_GPL(mt76_get_of_data_from_mtd);

int mt76_get_of_data_from_nvmem(struct mt76_dev *dev, void *eep,
                                const char *cell_name, int len)
{
        struct device_node *np = dev->dev->of_node;
        struct nvmem_cell *cell;
        const void *data;
        size_t retlen;
        int ret = 0;

        cell = of_nvmem_cell_get(np, cell_name);
        if (IS_ERR(cell))
                return PTR_ERR(cell);

        data = nvmem_cell_read(cell, &retlen);
        nvmem_cell_put(cell);

        if (IS_ERR(data))
                return PTR_ERR(data);

        if (retlen < len) {
                ret = -EINVAL;
                goto exit;
        }

        memcpy(eep, data, len);

exit:
        kfree(data);

        return ret;
}
EXPORT_SYMBOL_GPL(mt76_get_of_data_from_nvmem);

static int mt76_get_of_eeprom(struct mt76_dev *dev, void *eep, int len)
{
        struct device_node *np = dev->dev->of_node;
        int ret;

        if (!np)
                return -ENOENT;

        ret = mt76_get_of_eeprom_data(dev, eep, len);
        if (!ret)
                return 0;

        ret = mt76_get_of_data_from_mtd(dev, eep, 0, len);
        if (!ret)
                return 0;

        return mt76_get_of_data_from_nvmem(dev, eep, "eeprom", len);
}

int
mt76_eeprom_override(struct mt76_phy *phy)
{
        struct mt76_dev *dev = phy->dev;
        struct device_node *np = dev->dev->of_node;
        int err;

        err = of_get_mac_address(np, phy->macaddr);
        if (err == -EPROBE_DEFER)
                return err;

        if (!is_valid_ether_addr(phy->macaddr)) {
                eth_random_addr(phy->macaddr);
                dev_info(dev->dev,
                         "Invalid MAC address, using random address %pM\n",
                         phy->macaddr);
        }

        return 0;
}
EXPORT_SYMBOL_GPL(mt76_eeprom_override);

static bool mt76_string_prop_find(struct property *prop, const char *str)
{
        const char *cp = NULL;

        if (!prop || !str || !str[0])
                return false;

        while ((cp = of_prop_next_string(prop, cp)) != NULL)
                if (!strcasecmp(cp, str))
                        return true;

        return false;
}

struct device_node *
mt76_find_power_limits_node(struct mt76_dev *dev)
{
        struct device_node *np = dev->dev->of_node;
        const char *const region_names[] = {
                [NL80211_DFS_UNSET] = "ww",
                [NL80211_DFS_ETSI] = "etsi",
                [NL80211_DFS_FCC] = "fcc",
                [NL80211_DFS_JP] = "jp",
        };
        struct device_node *cur, *fallback = NULL;
        const char *region_name = NULL;

        if (dev->region < ARRAY_SIZE(region_names))
                region_name = region_names[dev->region];

        np = of_get_child_by_name(np, "power-limits");
        if (!np)
                return NULL;

        for_each_child_of_node(np, cur) {
                struct property *country = of_find_property(cur, "country", NULL);
                struct property *regd = of_find_property(cur, "regdomain", NULL);

                if (!country && !regd) {
                        fallback = cur;
                        continue;
                }

                if (mt76_string_prop_find(country, dev->alpha2) ||
                    mt76_string_prop_find(regd, region_name)) {
                        of_node_put(np);
                        return cur;
                }
        }

        of_node_put(np);
        return fallback;
}
EXPORT_SYMBOL_GPL(mt76_find_power_limits_node);

static const __be32 *
mt76_get_of_array(struct device_node *np, char *name, size_t *len, int min)
{
        struct property *prop = of_find_property(np, name, NULL);

        if (!prop || !prop->value || prop->length < min * 4)
                return NULL;

        *len = prop->length;

        return prop->value;
}

static const s8 *
mt76_get_of_array_s8(struct device_node *np, char *name, size_t *len, int min)
{
        struct property *prop = of_find_property(np, name, NULL);

        if (!prop || !prop->value || prop->length < min)
                return NULL;

        *len = prop->length;

        return prop->value;
}

struct device_node *
mt76_find_channel_node(struct device_node *np, struct ieee80211_channel *chan)
{
        struct device_node *cur;
        const __be32 *val;
        size_t len;

        for_each_child_of_node(np, cur) {
                val = mt76_get_of_array(cur, "channels", &len, 2);
                if (!val)
                        continue;

                while (len >= 2 * sizeof(*val)) {
                        if (chan->hw_value >= be32_to_cpu(val[0]) &&
                            chan->hw_value <= be32_to_cpu(val[1]))
                                return cur;

                        val += 2;
                        len -= 2 * sizeof(*val);
                }
        }

        return NULL;
}
EXPORT_SYMBOL_GPL(mt76_find_channel_node);


static s8
mt76_get_txs_delta(struct device_node *np, u8 nss)
{
        const __be32 *val;
        size_t len;

        val = mt76_get_of_array(np, "txs-delta", &len, nss);
        if (!val)
                return 0;

        return be32_to_cpu(val[nss - 1]);
}

static void
mt76_apply_array_limit(s8 *pwr, size_t pwr_len, const s8 *data,
                       s8 target_power, s8 nss_delta, s8 *max_power)
{
        int i;

        if (!data)
                return;

        for (i = 0; i < pwr_len; i++) {
                pwr[i] = min_t(s8, target_power, data[i] + nss_delta);
                *max_power = max(*max_power, pwr[i]);
        }
}

static void
mt76_apply_multi_array_limit(s8 *pwr, size_t pwr_len, s8 pwr_num,
                             const s8 *data, size_t len, s8 target_power,
                             s8 nss_delta)
{
        int i, cur;
        s8 max_power = -128;

        if (!data)
                return;

        cur = data[0];
        for (i = 0; i < pwr_num; i++) {
                if (len < pwr_len + 1)
                        break;

                mt76_apply_array_limit(pwr + pwr_len * i, pwr_len, data + 1,
                                       target_power, nss_delta, &max_power);
                if (--cur > 0)
                        continue;

                data += pwr_len + 1;
                len -= pwr_len + 1;
                if (!len)
                        break;

                cur = data[0];
        }
}

s8 mt76_get_rate_power_limits(struct mt76_phy *phy,
                              struct ieee80211_channel *chan,
                              struct mt76_power_limits *dest,
                              s8 target_power)
{
        struct mt76_dev *dev = phy->dev;
        struct device_node *np;
        const s8 *val;
        char name[16];
        u32 mcs_rates = dev->drv->mcs_rates;
        u32 ru_rates = ARRAY_SIZE(dest->ru[0]);
        char band;
        size_t len;
        s8 max_power = 0;
        s8 max_power_backoff = -127;
        s8 txs_delta;
        int n_chains = hweight16(phy->chainmask);
        s8 target_power_combine = target_power + mt76_tx_power_path_delta(n_chains);

        if (!mcs_rates)
                mcs_rates = 10;

        memset(dest, target_power, sizeof(*dest) - sizeof(dest->path));
        memset(&dest->path, 0, sizeof(dest->path));

        if (!IS_ENABLED(CONFIG_OF))
                return target_power;

        np = mt76_find_power_limits_node(dev);
        if (!np)
                return target_power;

        switch (chan->band) {
        case NL80211_BAND_2GHZ:
                band = '2';
                break;
        case NL80211_BAND_5GHZ:
                band = '5';
                break;
        case NL80211_BAND_6GHZ:
                band = '6';
                break;
        default:
                return target_power;
        }

        snprintf(name, sizeof(name), "txpower-%cg", band);
        np = of_get_child_by_name(np, name);
        if (!np)
                return target_power;

        np = mt76_find_channel_node(np, chan);
        if (!np)
                return target_power;

        txs_delta = mt76_get_txs_delta(np, hweight16(phy->chainmask));

        val = mt76_get_of_array_s8(np, "rates-cck", &len, ARRAY_SIZE(dest->cck));
        mt76_apply_array_limit(dest->cck, ARRAY_SIZE(dest->cck), val,
                               target_power, txs_delta, &max_power);

        val = mt76_get_of_array_s8(np, "rates-ofdm",
                                   &len, ARRAY_SIZE(dest->ofdm));
        mt76_apply_array_limit(dest->ofdm, ARRAY_SIZE(dest->ofdm), val,
                               target_power, txs_delta, &max_power);

        val = mt76_get_of_array_s8(np, "rates-mcs", &len, mcs_rates + 1);
        mt76_apply_multi_array_limit(dest->mcs[0], ARRAY_SIZE(dest->mcs[0]),
                                     ARRAY_SIZE(dest->mcs), val, len,
                                     target_power, txs_delta);

        val = mt76_get_of_array_s8(np, "rates-ru", &len, ru_rates + 1);
        mt76_apply_multi_array_limit(dest->ru[0], ARRAY_SIZE(dest->ru[0]),
                                     ARRAY_SIZE(dest->ru), val, len,
                                     target_power, txs_delta);

        max_power_backoff = max_power;
        val = mt76_get_of_array_s8(np, "paths-cck", &len, ARRAY_SIZE(dest->path.cck));
        mt76_apply_array_limit(dest->path.cck, ARRAY_SIZE(dest->path.cck), val,
                               target_power_combine, txs_delta, &max_power_backoff);

        val = mt76_get_of_array_s8(np, "paths-ofdm", &len, ARRAY_SIZE(dest->path.ofdm));
        mt76_apply_array_limit(dest->path.ofdm, ARRAY_SIZE(dest->path.ofdm), val,
                               target_power_combine, txs_delta, &max_power_backoff);

        val = mt76_get_of_array_s8(np, "paths-ofdm-bf", &len, ARRAY_SIZE(dest->path.ofdm_bf));
        mt76_apply_array_limit(dest->path.ofdm_bf, ARRAY_SIZE(dest->path.ofdm_bf), val,
                               target_power_combine, txs_delta, &max_power_backoff);

        val = mt76_get_of_array_s8(np, "paths-ru", &len, ARRAY_SIZE(dest->path.ru[0]) + 1);
        mt76_apply_multi_array_limit(dest->path.ru[0], ARRAY_SIZE(dest->path.ru[0]),
                                     ARRAY_SIZE(dest->path.ru), val, len,
                                     target_power_combine, txs_delta);

        val = mt76_get_of_array_s8(np, "paths-ru-bf", &len, ARRAY_SIZE(dest->path.ru_bf[0]) + 1);
        mt76_apply_multi_array_limit(dest->path.ru_bf[0], ARRAY_SIZE(dest->path.ru_bf[0]),
                                     ARRAY_SIZE(dest->path.ru_bf), val, len,
                                     target_power_combine, txs_delta);

        return max_power;
}
EXPORT_SYMBOL_GPL(mt76_get_rate_power_limits);

int
mt76_eeprom_init(struct mt76_dev *dev, int len)
{
        dev->eeprom.size = len;
        dev->eeprom.data = devm_kzalloc(dev->dev, len, GFP_KERNEL);
        if (!dev->eeprom.data)
                return -ENOMEM;

        return !mt76_get_of_eeprom(dev, dev->eeprom.data, len);
}
EXPORT_SYMBOL_GPL(mt76_eeprom_init);