xref: /linux/drivers/net/wireless/mediatek/mt76/eeprom.c (revision 65aa371ea52a92dd10826a2ea74bd2c395ee90a8)
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 
12 int mt76_get_of_eeprom(struct mt76_dev *dev, void *eep, int offset, int len)
13 {
14 #if defined(CONFIG_OF) && defined(CONFIG_MTD)
15 	struct device_node *np = dev->dev->of_node;
16 	struct mtd_info *mtd;
17 	const __be32 *list;
18 	const void *data;
19 	const char *part;
20 	phandle phandle;
21 	int size;
22 	size_t retlen;
23 	int ret;
24 
25 	if (!np)
26 		return -ENOENT;
27 
28 	data = of_get_property(np, "mediatek,eeprom-data", &size);
29 	if (data) {
30 		if (size > len)
31 			return -EINVAL;
32 
33 		memcpy(eep, data, size);
34 
35 		return 0;
36 	}
37 
38 	list = of_get_property(np, "mediatek,mtd-eeprom", &size);
39 	if (!list)
40 		return -ENOENT;
41 
42 	phandle = be32_to_cpup(list++);
43 	if (!phandle)
44 		return -ENOENT;
45 
46 	np = of_find_node_by_phandle(phandle);
47 	if (!np)
48 		return -EINVAL;
49 
50 	part = of_get_property(np, "label", NULL);
51 	if (!part)
52 		part = np->name;
53 
54 	mtd = get_mtd_device_nm(part);
55 	if (IS_ERR(mtd)) {
56 		ret =  PTR_ERR(mtd);
57 		goto out_put_node;
58 	}
59 
60 	if (size <= sizeof(*list)) {
61 		ret = -EINVAL;
62 		goto out_put_node;
63 	}
64 
65 	offset = be32_to_cpup(list);
66 	ret = mtd_read(mtd, offset, len, &retlen, eep);
67 	put_mtd_device(mtd);
68 	if (ret)
69 		goto out_put_node;
70 
71 	if (retlen < len) {
72 		ret = -EINVAL;
73 		goto out_put_node;
74 	}
75 
76 	if (of_property_read_bool(dev->dev->of_node, "big-endian")) {
77 		u8 *data = (u8 *)eep;
78 		int i;
79 
80 		/* convert eeprom data in Little Endian */
81 		for (i = 0; i < round_down(len, 2); i += 2)
82 			put_unaligned_le16(get_unaligned_be16(&data[i]),
83 					   &data[i]);
84 	}
85 
86 #ifdef CONFIG_NL80211_TESTMODE
87 	dev->test_mtd.name = devm_kstrdup(dev->dev, part, GFP_KERNEL);
88 	dev->test_mtd.offset = offset;
89 #endif
90 
91 out_put_node:
92 	of_node_put(np);
93 	return ret;
94 #else
95 	return -ENOENT;
96 #endif
97 }
98 EXPORT_SYMBOL_GPL(mt76_get_of_eeprom);
99 
100 void
101 mt76_eeprom_override(struct mt76_phy *phy)
102 {
103 	struct mt76_dev *dev = phy->dev;
104 	struct device_node *np = dev->dev->of_node;
105 
106 	of_get_mac_address(np, phy->macaddr);
107 
108 	if (!is_valid_ether_addr(phy->macaddr)) {
109 		eth_random_addr(phy->macaddr);
110 		dev_info(dev->dev,
111 			 "Invalid MAC address, using random address %pM\n",
112 			 phy->macaddr);
113 	}
114 }
115 EXPORT_SYMBOL_GPL(mt76_eeprom_override);
116 
117 static bool mt76_string_prop_find(struct property *prop, const char *str)
118 {
119 	const char *cp = NULL;
120 
121 	if (!prop || !str || !str[0])
122 		return false;
123 
124 	while ((cp = of_prop_next_string(prop, cp)) != NULL)
125 		if (!strcasecmp(cp, str))
126 			return true;
127 
128 	return false;
129 }
130 
131 static struct device_node *
132 mt76_find_power_limits_node(struct mt76_dev *dev)
133 {
134 	struct device_node *np = dev->dev->of_node;
135 	const char *const region_names[] = {
136 		[NL80211_DFS_ETSI] = "etsi",
137 		[NL80211_DFS_FCC] = "fcc",
138 		[NL80211_DFS_JP] = "jp",
139 	};
140 	struct device_node *cur, *fallback = NULL;
141 	const char *region_name = NULL;
142 
143 	if (dev->region < ARRAY_SIZE(region_names))
144 		region_name = region_names[dev->region];
145 
146 	np = of_get_child_by_name(np, "power-limits");
147 	if (!np)
148 		return NULL;
149 
150 	for_each_child_of_node(np, cur) {
151 		struct property *country = of_find_property(cur, "country", NULL);
152 		struct property *regd = of_find_property(cur, "regdomain", NULL);
153 
154 		if (!country && !regd) {
155 			fallback = cur;
156 			continue;
157 		}
158 
159 		if (mt76_string_prop_find(country, dev->alpha2) ||
160 		    mt76_string_prop_find(regd, region_name))
161 			return cur;
162 	}
163 
164 	return fallback;
165 }
166 
167 static const __be32 *
168 mt76_get_of_array(struct device_node *np, char *name, size_t *len, int min)
169 {
170 	struct property *prop = of_find_property(np, name, NULL);
171 
172 	if (!prop || !prop->value || prop->length < min * 4)
173 		return NULL;
174 
175 	*len = prop->length;
176 
177 	return prop->value;
178 }
179 
180 static struct device_node *
181 mt76_find_channel_node(struct device_node *np, struct ieee80211_channel *chan)
182 {
183 	struct device_node *cur;
184 	const __be32 *val;
185 	size_t len;
186 
187 	for_each_child_of_node(np, cur) {
188 		val = mt76_get_of_array(cur, "channels", &len, 2);
189 		if (!val)
190 			continue;
191 
192 		while (len >= 2 * sizeof(*val)) {
193 			if (chan->hw_value >= be32_to_cpu(val[0]) &&
194 			    chan->hw_value <= be32_to_cpu(val[1]))
195 				return cur;
196 
197 			val += 2;
198 			len -= 2 * sizeof(*val);
199 		}
200 	}
201 
202 	return NULL;
203 }
204 
205 static s8
206 mt76_get_txs_delta(struct device_node *np, u8 nss)
207 {
208 	const __be32 *val;
209 	size_t len;
210 
211 	val = mt76_get_of_array(np, "txs-delta", &len, nss);
212 	if (!val)
213 		return 0;
214 
215 	return be32_to_cpu(val[nss - 1]);
216 }
217 
218 static void
219 mt76_apply_array_limit(s8 *pwr, size_t pwr_len, const __be32 *data,
220 		       s8 target_power, s8 nss_delta, s8 *max_power)
221 {
222 	int i;
223 
224 	if (!data)
225 		return;
226 
227 	for (i = 0; i < pwr_len; i++) {
228 		pwr[i] = min_t(s8, target_power,
229 			       be32_to_cpu(data[i]) + nss_delta);
230 		*max_power = max(*max_power, pwr[i]);
231 	}
232 }
233 
234 static void
235 mt76_apply_multi_array_limit(s8 *pwr, size_t pwr_len, s8 pwr_num,
236 			     const __be32 *data, size_t len, s8 target_power,
237 			     s8 nss_delta, s8 *max_power)
238 {
239 	int i, cur;
240 
241 	if (!data)
242 		return;
243 
244 	len /= 4;
245 	cur = be32_to_cpu(data[0]);
246 	for (i = 0; i < pwr_num; i++) {
247 		if (len < pwr_len + 1)
248 			break;
249 
250 		mt76_apply_array_limit(pwr + pwr_len * i, pwr_len, data + 1,
251 				       target_power, nss_delta, max_power);
252 		if (--cur > 0)
253 			continue;
254 
255 		data += pwr_len + 1;
256 		len -= pwr_len + 1;
257 		if (!len)
258 			break;
259 
260 		cur = be32_to_cpu(data[0]);
261 	}
262 }
263 
264 s8 mt76_get_rate_power_limits(struct mt76_phy *phy,
265 			      struct ieee80211_channel *chan,
266 			      struct mt76_power_limits *dest,
267 			      s8 target_power)
268 {
269 	struct mt76_dev *dev = phy->dev;
270 	struct device_node *np;
271 	const __be32 *val;
272 	char name[16];
273 	u32 mcs_rates = dev->drv->mcs_rates;
274 	u32 ru_rates = ARRAY_SIZE(dest->ru[0]);
275 	char band;
276 	size_t len;
277 	s8 max_power = 0;
278 	s8 txs_delta;
279 
280 	if (!mcs_rates)
281 		mcs_rates = 10;
282 
283 	memset(dest, target_power, sizeof(*dest));
284 
285 	if (!IS_ENABLED(CONFIG_OF))
286 		return target_power;
287 
288 	np = mt76_find_power_limits_node(dev);
289 	if (!np)
290 		return target_power;
291 
292 	switch (chan->band) {
293 	case NL80211_BAND_2GHZ:
294 		band = '2';
295 		break;
296 	case NL80211_BAND_5GHZ:
297 		band = '5';
298 		break;
299 	case NL80211_BAND_6GHZ:
300 		band = '6';
301 		break;
302 	default:
303 		return target_power;
304 	}
305 
306 	snprintf(name, sizeof(name), "txpower-%cg", band);
307 	np = of_get_child_by_name(np, name);
308 	if (!np)
309 		return target_power;
310 
311 	np = mt76_find_channel_node(np, chan);
312 	if (!np)
313 		return target_power;
314 
315 	txs_delta = mt76_get_txs_delta(np, hweight8(phy->antenna_mask));
316 
317 	val = mt76_get_of_array(np, "rates-cck", &len, ARRAY_SIZE(dest->cck));
318 	mt76_apply_array_limit(dest->cck, ARRAY_SIZE(dest->cck), val,
319 			       target_power, txs_delta, &max_power);
320 
321 	val = mt76_get_of_array(np, "rates-ofdm",
322 				&len, ARRAY_SIZE(dest->ofdm));
323 	mt76_apply_array_limit(dest->ofdm, ARRAY_SIZE(dest->ofdm), val,
324 			       target_power, txs_delta, &max_power);
325 
326 	val = mt76_get_of_array(np, "rates-mcs", &len, mcs_rates + 1);
327 	mt76_apply_multi_array_limit(dest->mcs[0], ARRAY_SIZE(dest->mcs[0]),
328 				     ARRAY_SIZE(dest->mcs), val, len,
329 				     target_power, txs_delta, &max_power);
330 
331 	val = mt76_get_of_array(np, "rates-ru", &len, ru_rates + 1);
332 	mt76_apply_multi_array_limit(dest->ru[0], ARRAY_SIZE(dest->ru[0]),
333 				     ARRAY_SIZE(dest->ru), val, len,
334 				     target_power, txs_delta, &max_power);
335 
336 	return max_power;
337 }
338 EXPORT_SYMBOL_GPL(mt76_get_rate_power_limits);
339 
340 int
341 mt76_eeprom_init(struct mt76_dev *dev, int len)
342 {
343 	dev->eeprom.size = len;
344 	dev->eeprom.data = devm_kzalloc(dev->dev, len, GFP_KERNEL);
345 	if (!dev->eeprom.data)
346 		return -ENOMEM;
347 
348 	return !mt76_get_of_eeprom(dev, dev->eeprom.data, 0, len);
349 }
350 EXPORT_SYMBOL_GPL(mt76_eeprom_init);
351