xref: /linux/drivers/net/wireless/mediatek/mt76/eeprom.c (revision 4b660dbd9ee2059850fd30e0df420ca7a38a1856)
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/nvmem-consumer.h>
10 #include <linux/etherdevice.h>
11 #include "mt76.h"
12 
13 static int mt76_get_of_eeprom_data(struct mt76_dev *dev, void *eep, int len)
14 {
15 	struct device_node *np = dev->dev->of_node;
16 	const void *data;
17 	int size;
18 
19 	data = of_get_property(np, "mediatek,eeprom-data", &size);
20 	if (!data)
21 		return -ENOENT;
22 
23 	if (size > len)
24 		return -EINVAL;
25 
26 	memcpy(eep, data, size);
27 
28 	return 0;
29 }
30 
31 int mt76_get_of_data_from_mtd(struct mt76_dev *dev, void *eep, int offset, int len)
32 {
33 #ifdef CONFIG_MTD
34 	struct device_node *np = dev->dev->of_node;
35 	struct mtd_info *mtd;
36 	const __be32 *list;
37 	const char *part;
38 	phandle phandle;
39 	size_t retlen;
40 	int size;
41 	int ret;
42 
43 	list = of_get_property(np, "mediatek,mtd-eeprom", &size);
44 	if (!list)
45 		return -ENOENT;
46 
47 	phandle = be32_to_cpup(list++);
48 	if (!phandle)
49 		return -ENOENT;
50 
51 	np = of_find_node_by_phandle(phandle);
52 	if (!np)
53 		return -EINVAL;
54 
55 	part = of_get_property(np, "label", NULL);
56 	if (!part)
57 		part = np->name;
58 
59 	mtd = get_mtd_device_nm(part);
60 	if (IS_ERR(mtd)) {
61 		ret =  PTR_ERR(mtd);
62 		goto out_put_node;
63 	}
64 
65 	if (size <= sizeof(*list)) {
66 		ret = -EINVAL;
67 		goto out_put_node;
68 	}
69 
70 	offset += be32_to_cpup(list);
71 	ret = mtd_read(mtd, offset, len, &retlen, eep);
72 	put_mtd_device(mtd);
73 	if (mtd_is_bitflip(ret))
74 		ret = 0;
75 	if (ret) {
76 		dev_err(dev->dev, "reading EEPROM from mtd %s failed: %i\n",
77 			part, ret);
78 		goto out_put_node;
79 	}
80 
81 	if (retlen < len) {
82 		ret = -EINVAL;
83 		goto out_put_node;
84 	}
85 
86 	if (of_property_read_bool(dev->dev->of_node, "big-endian")) {
87 		u8 *data = (u8 *)eep;
88 		int i;
89 
90 		/* convert eeprom data in Little Endian */
91 		for (i = 0; i < round_down(len, 2); i += 2)
92 			put_unaligned_le16(get_unaligned_be16(&data[i]),
93 					   &data[i]);
94 	}
95 
96 #ifdef CONFIG_NL80211_TESTMODE
97 	dev->test_mtd.name = devm_kstrdup(dev->dev, part, GFP_KERNEL);
98 	dev->test_mtd.offset = offset;
99 #endif
100 
101 out_put_node:
102 	of_node_put(np);
103 	return ret;
104 #else
105 	return -ENOENT;
106 #endif
107 }
108 EXPORT_SYMBOL_GPL(mt76_get_of_data_from_mtd);
109 
110 int mt76_get_of_data_from_nvmem(struct mt76_dev *dev, void *eep,
111 				const char *cell_name, int len)
112 {
113 	struct device_node *np = dev->dev->of_node;
114 	struct nvmem_cell *cell;
115 	const void *data;
116 	size_t retlen;
117 	int ret = 0;
118 
119 	cell = of_nvmem_cell_get(np, cell_name);
120 	if (IS_ERR(cell))
121 		return PTR_ERR(cell);
122 
123 	data = nvmem_cell_read(cell, &retlen);
124 	nvmem_cell_put(cell);
125 
126 	if (IS_ERR(data))
127 		return PTR_ERR(data);
128 
129 	if (retlen < len) {
130 		ret = -EINVAL;
131 		goto exit;
132 	}
133 
134 	memcpy(eep, data, len);
135 
136 exit:
137 	kfree(data);
138 
139 	return ret;
140 }
141 EXPORT_SYMBOL_GPL(mt76_get_of_data_from_nvmem);
142 
143 static int mt76_get_of_eeprom(struct mt76_dev *dev, void *eep, int len)
144 {
145 	struct device_node *np = dev->dev->of_node;
146 	int ret;
147 
148 	if (!np)
149 		return -ENOENT;
150 
151 	ret = mt76_get_of_eeprom_data(dev, eep, len);
152 	if (!ret)
153 		return 0;
154 
155 	ret = mt76_get_of_data_from_mtd(dev, eep, 0, len);
156 	if (!ret)
157 		return 0;
158 
159 	return mt76_get_of_data_from_nvmem(dev, eep, "eeprom", len);
160 }
161 
162 void
163 mt76_eeprom_override(struct mt76_phy *phy)
164 {
165 	struct mt76_dev *dev = phy->dev;
166 	struct device_node *np = dev->dev->of_node;
167 
168 	of_get_mac_address(np, phy->macaddr);
169 
170 	if (!is_valid_ether_addr(phy->macaddr)) {
171 		eth_random_addr(phy->macaddr);
172 		dev_info(dev->dev,
173 			 "Invalid MAC address, using random address %pM\n",
174 			 phy->macaddr);
175 	}
176 }
177 EXPORT_SYMBOL_GPL(mt76_eeprom_override);
178 
179 static bool mt76_string_prop_find(struct property *prop, const char *str)
180 {
181 	const char *cp = NULL;
182 
183 	if (!prop || !str || !str[0])
184 		return false;
185 
186 	while ((cp = of_prop_next_string(prop, cp)) != NULL)
187 		if (!strcasecmp(cp, str))
188 			return true;
189 
190 	return false;
191 }
192 
193 struct device_node *
194 mt76_find_power_limits_node(struct mt76_dev *dev)
195 {
196 	struct device_node *np = dev->dev->of_node;
197 	const char *const region_names[] = {
198 		[NL80211_DFS_UNSET] = "ww",
199 		[NL80211_DFS_ETSI] = "etsi",
200 		[NL80211_DFS_FCC] = "fcc",
201 		[NL80211_DFS_JP] = "jp",
202 	};
203 	struct device_node *cur, *fallback = NULL;
204 	const char *region_name = NULL;
205 
206 	if (dev->region < ARRAY_SIZE(region_names))
207 		region_name = region_names[dev->region];
208 
209 	np = of_get_child_by_name(np, "power-limits");
210 	if (!np)
211 		return NULL;
212 
213 	for_each_child_of_node(np, cur) {
214 		struct property *country = of_find_property(cur, "country", NULL);
215 		struct property *regd = of_find_property(cur, "regdomain", NULL);
216 
217 		if (!country && !regd) {
218 			fallback = cur;
219 			continue;
220 		}
221 
222 		if (mt76_string_prop_find(country, dev->alpha2) ||
223 		    mt76_string_prop_find(regd, region_name)) {
224 			of_node_put(np);
225 			return cur;
226 		}
227 	}
228 
229 	of_node_put(np);
230 	return fallback;
231 }
232 EXPORT_SYMBOL_GPL(mt76_find_power_limits_node);
233 
234 static const __be32 *
235 mt76_get_of_array(struct device_node *np, char *name, size_t *len, int min)
236 {
237 	struct property *prop = of_find_property(np, name, NULL);
238 
239 	if (!prop || !prop->value || prop->length < min * 4)
240 		return NULL;
241 
242 	*len = prop->length;
243 
244 	return prop->value;
245 }
246 
247 struct device_node *
248 mt76_find_channel_node(struct device_node *np, struct ieee80211_channel *chan)
249 {
250 	struct device_node *cur;
251 	const __be32 *val;
252 	size_t len;
253 
254 	for_each_child_of_node(np, cur) {
255 		val = mt76_get_of_array(cur, "channels", &len, 2);
256 		if (!val)
257 			continue;
258 
259 		while (len >= 2 * sizeof(*val)) {
260 			if (chan->hw_value >= be32_to_cpu(val[0]) &&
261 			    chan->hw_value <= be32_to_cpu(val[1]))
262 				return cur;
263 
264 			val += 2;
265 			len -= 2 * sizeof(*val);
266 		}
267 	}
268 
269 	return NULL;
270 }
271 EXPORT_SYMBOL_GPL(mt76_find_channel_node);
272 
273 
274 static s8
275 mt76_get_txs_delta(struct device_node *np, u8 nss)
276 {
277 	const __be32 *val;
278 	size_t len;
279 
280 	val = mt76_get_of_array(np, "txs-delta", &len, nss);
281 	if (!val)
282 		return 0;
283 
284 	return be32_to_cpu(val[nss - 1]);
285 }
286 
287 static void
288 mt76_apply_array_limit(s8 *pwr, size_t pwr_len, const __be32 *data,
289 		       s8 target_power, s8 nss_delta, s8 *max_power)
290 {
291 	int i;
292 
293 	if (!data)
294 		return;
295 
296 	for (i = 0; i < pwr_len; i++) {
297 		pwr[i] = min_t(s8, target_power,
298 			       be32_to_cpu(data[i]) + nss_delta);
299 		*max_power = max(*max_power, pwr[i]);
300 	}
301 }
302 
303 static void
304 mt76_apply_multi_array_limit(s8 *pwr, size_t pwr_len, s8 pwr_num,
305 			     const __be32 *data, size_t len, s8 target_power,
306 			     s8 nss_delta, s8 *max_power)
307 {
308 	int i, cur;
309 
310 	if (!data)
311 		return;
312 
313 	len /= 4;
314 	cur = be32_to_cpu(data[0]);
315 	for (i = 0; i < pwr_num; i++) {
316 		if (len < pwr_len + 1)
317 			break;
318 
319 		mt76_apply_array_limit(pwr + pwr_len * i, pwr_len, data + 1,
320 				       target_power, nss_delta, max_power);
321 		if (--cur > 0)
322 			continue;
323 
324 		data += pwr_len + 1;
325 		len -= pwr_len + 1;
326 		if (!len)
327 			break;
328 
329 		cur = be32_to_cpu(data[0]);
330 	}
331 }
332 
333 s8 mt76_get_rate_power_limits(struct mt76_phy *phy,
334 			      struct ieee80211_channel *chan,
335 			      struct mt76_power_limits *dest,
336 			      s8 target_power)
337 {
338 	struct mt76_dev *dev = phy->dev;
339 	struct device_node *np;
340 	const __be32 *val;
341 	char name[16];
342 	u32 mcs_rates = dev->drv->mcs_rates;
343 	u32 ru_rates = ARRAY_SIZE(dest->ru[0]);
344 	char band;
345 	size_t len;
346 	s8 max_power = 0;
347 	s8 txs_delta;
348 
349 	if (!mcs_rates)
350 		mcs_rates = 10;
351 
352 	memset(dest, target_power, sizeof(*dest));
353 
354 	if (!IS_ENABLED(CONFIG_OF))
355 		return target_power;
356 
357 	np = mt76_find_power_limits_node(dev);
358 	if (!np)
359 		return target_power;
360 
361 	switch (chan->band) {
362 	case NL80211_BAND_2GHZ:
363 		band = '2';
364 		break;
365 	case NL80211_BAND_5GHZ:
366 		band = '5';
367 		break;
368 	case NL80211_BAND_6GHZ:
369 		band = '6';
370 		break;
371 	default:
372 		return target_power;
373 	}
374 
375 	snprintf(name, sizeof(name), "txpower-%cg", band);
376 	np = of_get_child_by_name(np, name);
377 	if (!np)
378 		return target_power;
379 
380 	np = mt76_find_channel_node(np, chan);
381 	if (!np)
382 		return target_power;
383 
384 	txs_delta = mt76_get_txs_delta(np, hweight16(phy->chainmask));
385 
386 	val = mt76_get_of_array(np, "rates-cck", &len, ARRAY_SIZE(dest->cck));
387 	mt76_apply_array_limit(dest->cck, ARRAY_SIZE(dest->cck), val,
388 			       target_power, txs_delta, &max_power);
389 
390 	val = mt76_get_of_array(np, "rates-ofdm",
391 				&len, ARRAY_SIZE(dest->ofdm));
392 	mt76_apply_array_limit(dest->ofdm, ARRAY_SIZE(dest->ofdm), val,
393 			       target_power, txs_delta, &max_power);
394 
395 	val = mt76_get_of_array(np, "rates-mcs", &len, mcs_rates + 1);
396 	mt76_apply_multi_array_limit(dest->mcs[0], ARRAY_SIZE(dest->mcs[0]),
397 				     ARRAY_SIZE(dest->mcs), val, len,
398 				     target_power, txs_delta, &max_power);
399 
400 	val = mt76_get_of_array(np, "rates-ru", &len, ru_rates + 1);
401 	mt76_apply_multi_array_limit(dest->ru[0], ARRAY_SIZE(dest->ru[0]),
402 				     ARRAY_SIZE(dest->ru), val, len,
403 				     target_power, txs_delta, &max_power);
404 
405 	return max_power;
406 }
407 EXPORT_SYMBOL_GPL(mt76_get_rate_power_limits);
408 
409 int
410 mt76_eeprom_init(struct mt76_dev *dev, int len)
411 {
412 	dev->eeprom.size = len;
413 	dev->eeprom.data = devm_kzalloc(dev->dev, len, GFP_KERNEL);
414 	if (!dev->eeprom.data)
415 		return -ENOMEM;
416 
417 	return !mt76_get_of_eeprom(dev, dev->eeprom.data, len);
418 }
419 EXPORT_SYMBOL_GPL(mt76_eeprom_init);
420