1 // SPDX-License-Identifier: ISC
2 /*
3  * Copyright (c) 2013 Broadcom Corporation
4  */
5 
6 #include <linux/efi.h>
7 #include <linux/kernel.h>
8 #include <linux/slab.h>
9 #include <linux/device.h>
10 #include <linux/firmware.h>
11 #include <linux/module.h>
12 #include <linux/bcm47xx_nvram.h>
13 
14 #include "debug.h"
15 #include "firmware.h"
16 #include "core.h"
17 #include "common.h"
18 #include "chip.h"
19 
20 #define BRCMF_FW_MAX_NVRAM_SIZE			64000
21 #define BRCMF_FW_NVRAM_DEVPATH_LEN		19	/* devpath0=pcie/1/4/ */
22 #define BRCMF_FW_NVRAM_PCIEDEV_LEN		10	/* pcie/1/4/ + \0 */
23 #define BRCMF_FW_DEFAULT_BOARDREV		"boardrev=0xff"
24 
25 enum nvram_parser_state {
26 	IDLE,
27 	KEY,
28 	VALUE,
29 	COMMENT,
30 	END
31 };
32 
33 /**
34  * struct nvram_parser - internal info for parser.
35  *
36  * @state: current parser state.
37  * @data: input buffer being parsed.
38  * @nvram: output buffer with parse result.
39  * @nvram_len: length of parse result.
40  * @line: current line.
41  * @column: current column in line.
42  * @pos: byte offset in input buffer.
43  * @entry: start position of key,value entry.
44  * @multi_dev_v1: detect pcie multi device v1 (compressed).
45  * @multi_dev_v2: detect pcie multi device v2.
46  * @boardrev_found: nvram contains boardrev information.
47  */
48 struct nvram_parser {
49 	enum nvram_parser_state state;
50 	const u8 *data;
51 	u8 *nvram;
52 	u32 nvram_len;
53 	u32 line;
54 	u32 column;
55 	u32 pos;
56 	u32 entry;
57 	bool multi_dev_v1;
58 	bool multi_dev_v2;
59 	bool boardrev_found;
60 };
61 
62 /*
63  * is_nvram_char() - check if char is a valid one for NVRAM entry
64  *
65  * It accepts all printable ASCII chars except for '#' which opens a comment.
66  * Please note that ' ' (space) while accepted is not a valid key name char.
67  */
68 static bool is_nvram_char(char c)
69 {
70 	/* comment marker excluded */
71 	if (c == '#')
72 		return false;
73 
74 	/* key and value may have any other readable character */
75 	return (c >= 0x20 && c < 0x7f);
76 }
77 
78 static bool is_whitespace(char c)
79 {
80 	return (c == ' ' || c == '\r' || c == '\n' || c == '\t');
81 }
82 
83 static enum nvram_parser_state brcmf_nvram_handle_idle(struct nvram_parser *nvp)
84 {
85 	char c;
86 
87 	c = nvp->data[nvp->pos];
88 	if (c == '\n')
89 		return COMMENT;
90 	if (is_whitespace(c) || c == '\0')
91 		goto proceed;
92 	if (c == '#')
93 		return COMMENT;
94 	if (is_nvram_char(c)) {
95 		nvp->entry = nvp->pos;
96 		return KEY;
97 	}
98 	brcmf_dbg(INFO, "warning: ln=%d:col=%d: ignoring invalid character\n",
99 		  nvp->line, nvp->column);
100 proceed:
101 	nvp->column++;
102 	nvp->pos++;
103 	return IDLE;
104 }
105 
106 static enum nvram_parser_state brcmf_nvram_handle_key(struct nvram_parser *nvp)
107 {
108 	enum nvram_parser_state st = nvp->state;
109 	char c;
110 
111 	c = nvp->data[nvp->pos];
112 	if (c == '=') {
113 		/* ignore RAW1 by treating as comment */
114 		if (strncmp(&nvp->data[nvp->entry], "RAW1", 4) == 0)
115 			st = COMMENT;
116 		else
117 			st = VALUE;
118 		if (strncmp(&nvp->data[nvp->entry], "devpath", 7) == 0)
119 			nvp->multi_dev_v1 = true;
120 		if (strncmp(&nvp->data[nvp->entry], "pcie/", 5) == 0)
121 			nvp->multi_dev_v2 = true;
122 		if (strncmp(&nvp->data[nvp->entry], "boardrev", 8) == 0)
123 			nvp->boardrev_found = true;
124 	} else if (!is_nvram_char(c) || c == ' ') {
125 		brcmf_dbg(INFO, "warning: ln=%d:col=%d: '=' expected, skip invalid key entry\n",
126 			  nvp->line, nvp->column);
127 		return COMMENT;
128 	}
129 
130 	nvp->column++;
131 	nvp->pos++;
132 	return st;
133 }
134 
135 static enum nvram_parser_state
136 brcmf_nvram_handle_value(struct nvram_parser *nvp)
137 {
138 	char c;
139 	char *skv;
140 	char *ekv;
141 	u32 cplen;
142 
143 	c = nvp->data[nvp->pos];
144 	if (!is_nvram_char(c)) {
145 		/* key,value pair complete */
146 		ekv = (u8 *)&nvp->data[nvp->pos];
147 		skv = (u8 *)&nvp->data[nvp->entry];
148 		cplen = ekv - skv;
149 		if (nvp->nvram_len + cplen + 1 >= BRCMF_FW_MAX_NVRAM_SIZE)
150 			return END;
151 		/* copy to output buffer */
152 		memcpy(&nvp->nvram[nvp->nvram_len], skv, cplen);
153 		nvp->nvram_len += cplen;
154 		nvp->nvram[nvp->nvram_len] = '\0';
155 		nvp->nvram_len++;
156 		return IDLE;
157 	}
158 	nvp->pos++;
159 	nvp->column++;
160 	return VALUE;
161 }
162 
163 static enum nvram_parser_state
164 brcmf_nvram_handle_comment(struct nvram_parser *nvp)
165 {
166 	char *eoc, *sol;
167 
168 	sol = (char *)&nvp->data[nvp->pos];
169 	eoc = strchr(sol, '\n');
170 	if (!eoc) {
171 		eoc = strchr(sol, '\0');
172 		if (!eoc)
173 			return END;
174 	}
175 
176 	/* eat all moving to next line */
177 	nvp->line++;
178 	nvp->column = 1;
179 	nvp->pos += (eoc - sol) + 1;
180 	return IDLE;
181 }
182 
183 static enum nvram_parser_state brcmf_nvram_handle_end(struct nvram_parser *nvp)
184 {
185 	/* final state */
186 	return END;
187 }
188 
189 static enum nvram_parser_state
190 (*nv_parser_states[])(struct nvram_parser *nvp) = {
191 	brcmf_nvram_handle_idle,
192 	brcmf_nvram_handle_key,
193 	brcmf_nvram_handle_value,
194 	brcmf_nvram_handle_comment,
195 	brcmf_nvram_handle_end
196 };
197 
198 static int brcmf_init_nvram_parser(struct nvram_parser *nvp,
199 				   const u8 *data, size_t data_len)
200 {
201 	size_t size;
202 
203 	memset(nvp, 0, sizeof(*nvp));
204 	nvp->data = data;
205 	/* Limit size to MAX_NVRAM_SIZE, some files contain lot of comment */
206 	if (data_len > BRCMF_FW_MAX_NVRAM_SIZE)
207 		size = BRCMF_FW_MAX_NVRAM_SIZE;
208 	else
209 		size = data_len;
210 	/* Alloc for extra 0 byte + roundup by 4 + length field */
211 	size += 1 + 3 + sizeof(u32);
212 	nvp->nvram = kzalloc(size, GFP_KERNEL);
213 	if (!nvp->nvram)
214 		return -ENOMEM;
215 
216 	nvp->line = 1;
217 	nvp->column = 1;
218 	return 0;
219 }
220 
221 /* brcmf_fw_strip_multi_v1 :Some nvram files contain settings for multiple
222  * devices. Strip it down for one device, use domain_nr/bus_nr to determine
223  * which data is to be returned. v1 is the version where nvram is stored
224  * compressed and "devpath" maps to index for valid entries.
225  */
226 static void brcmf_fw_strip_multi_v1(struct nvram_parser *nvp, u16 domain_nr,
227 				    u16 bus_nr)
228 {
229 	/* Device path with a leading '=' key-value separator */
230 	char pci_path[] = "=pci/?/?";
231 	size_t pci_len;
232 	char pcie_path[] = "=pcie/?/?";
233 	size_t pcie_len;
234 
235 	u32 i, j;
236 	bool found;
237 	u8 *nvram;
238 	u8 id;
239 
240 	nvram = kzalloc(nvp->nvram_len + 1 + 3 + sizeof(u32), GFP_KERNEL);
241 	if (!nvram)
242 		goto fail;
243 
244 	/* min length: devpath0=pcie/1/4/ + 0:x=y */
245 	if (nvp->nvram_len < BRCMF_FW_NVRAM_DEVPATH_LEN + 6)
246 		goto fail;
247 
248 	/* First search for the devpathX and see if it is the configuration
249 	 * for domain_nr/bus_nr. Search complete nvp
250 	 */
251 	snprintf(pci_path, sizeof(pci_path), "=pci/%d/%d", domain_nr,
252 		 bus_nr);
253 	pci_len = strlen(pci_path);
254 	snprintf(pcie_path, sizeof(pcie_path), "=pcie/%d/%d", domain_nr,
255 		 bus_nr);
256 	pcie_len = strlen(pcie_path);
257 	found = false;
258 	i = 0;
259 	while (i < nvp->nvram_len - BRCMF_FW_NVRAM_DEVPATH_LEN) {
260 		/* Format: devpathX=pcie/Y/Z/
261 		 * Y = domain_nr, Z = bus_nr, X = virtual ID
262 		 */
263 		if (strncmp(&nvp->nvram[i], "devpath", 7) == 0 &&
264 		    (!strncmp(&nvp->nvram[i + 8], pci_path, pci_len) ||
265 		     !strncmp(&nvp->nvram[i + 8], pcie_path, pcie_len))) {
266 			id = nvp->nvram[i + 7] - '0';
267 			found = true;
268 			break;
269 		}
270 		while (nvp->nvram[i] != 0)
271 			i++;
272 		i++;
273 	}
274 	if (!found)
275 		goto fail;
276 
277 	/* Now copy all valid entries, release old nvram and assign new one */
278 	i = 0;
279 	j = 0;
280 	while (i < nvp->nvram_len) {
281 		if ((nvp->nvram[i] - '0' == id) && (nvp->nvram[i + 1] == ':')) {
282 			i += 2;
283 			if (strncmp(&nvp->nvram[i], "boardrev", 8) == 0)
284 				nvp->boardrev_found = true;
285 			while (nvp->nvram[i] != 0) {
286 				nvram[j] = nvp->nvram[i];
287 				i++;
288 				j++;
289 			}
290 			nvram[j] = 0;
291 			j++;
292 		}
293 		while (nvp->nvram[i] != 0)
294 			i++;
295 		i++;
296 	}
297 	kfree(nvp->nvram);
298 	nvp->nvram = nvram;
299 	nvp->nvram_len = j;
300 	return;
301 
302 fail:
303 	kfree(nvram);
304 	nvp->nvram_len = 0;
305 }
306 
307 /* brcmf_fw_strip_multi_v2 :Some nvram files contain settings for multiple
308  * devices. Strip it down for one device, use domain_nr/bus_nr to determine
309  * which data is to be returned. v2 is the version where nvram is stored
310  * uncompressed, all relevant valid entries are identified by
311  * pcie/domain_nr/bus_nr:
312  */
313 static void brcmf_fw_strip_multi_v2(struct nvram_parser *nvp, u16 domain_nr,
314 				    u16 bus_nr)
315 {
316 	char prefix[BRCMF_FW_NVRAM_PCIEDEV_LEN];
317 	size_t len;
318 	u32 i, j;
319 	u8 *nvram;
320 
321 	nvram = kzalloc(nvp->nvram_len + 1 + 3 + sizeof(u32), GFP_KERNEL);
322 	if (!nvram)
323 		goto fail;
324 
325 	/* Copy all valid entries, release old nvram and assign new one.
326 	 * Valid entries are of type pcie/X/Y/ where X = domain_nr and
327 	 * Y = bus_nr.
328 	 */
329 	snprintf(prefix, sizeof(prefix), "pcie/%d/%d/", domain_nr, bus_nr);
330 	len = strlen(prefix);
331 	i = 0;
332 	j = 0;
333 	while (i < nvp->nvram_len - len) {
334 		if (strncmp(&nvp->nvram[i], prefix, len) == 0) {
335 			i += len;
336 			if (strncmp(&nvp->nvram[i], "boardrev", 8) == 0)
337 				nvp->boardrev_found = true;
338 			while (nvp->nvram[i] != 0) {
339 				nvram[j] = nvp->nvram[i];
340 				i++;
341 				j++;
342 			}
343 			nvram[j] = 0;
344 			j++;
345 		}
346 		while (nvp->nvram[i] != 0)
347 			i++;
348 		i++;
349 	}
350 	kfree(nvp->nvram);
351 	nvp->nvram = nvram;
352 	nvp->nvram_len = j;
353 	return;
354 fail:
355 	kfree(nvram);
356 	nvp->nvram_len = 0;
357 }
358 
359 static void brcmf_fw_add_defaults(struct nvram_parser *nvp)
360 {
361 	if (nvp->boardrev_found)
362 		return;
363 
364 	memcpy(&nvp->nvram[nvp->nvram_len], &BRCMF_FW_DEFAULT_BOARDREV,
365 	       strlen(BRCMF_FW_DEFAULT_BOARDREV));
366 	nvp->nvram_len += strlen(BRCMF_FW_DEFAULT_BOARDREV);
367 	nvp->nvram[nvp->nvram_len] = '\0';
368 	nvp->nvram_len++;
369 }
370 
371 /* brcmf_nvram_strip :Takes a buffer of "<var>=<value>\n" lines read from a fil
372  * and ending in a NUL. Removes carriage returns, empty lines, comment lines,
373  * and converts newlines to NULs. Shortens buffer as needed and pads with NULs.
374  * End of buffer is completed with token identifying length of buffer.
375  */
376 static void *brcmf_fw_nvram_strip(const u8 *data, size_t data_len,
377 				  u32 *new_length, u16 domain_nr, u16 bus_nr)
378 {
379 	struct nvram_parser nvp;
380 	u32 pad;
381 	u32 token;
382 	__le32 token_le;
383 
384 	if (brcmf_init_nvram_parser(&nvp, data, data_len) < 0)
385 		return NULL;
386 
387 	while (nvp.pos < data_len) {
388 		nvp.state = nv_parser_states[nvp.state](&nvp);
389 		if (nvp.state == END)
390 			break;
391 	}
392 	if (nvp.multi_dev_v1) {
393 		nvp.boardrev_found = false;
394 		brcmf_fw_strip_multi_v1(&nvp, domain_nr, bus_nr);
395 	} else if (nvp.multi_dev_v2) {
396 		nvp.boardrev_found = false;
397 		brcmf_fw_strip_multi_v2(&nvp, domain_nr, bus_nr);
398 	}
399 
400 	if (nvp.nvram_len == 0) {
401 		kfree(nvp.nvram);
402 		return NULL;
403 	}
404 
405 	brcmf_fw_add_defaults(&nvp);
406 
407 	pad = nvp.nvram_len;
408 	*new_length = roundup(nvp.nvram_len + 1, 4);
409 	while (pad != *new_length) {
410 		nvp.nvram[pad] = 0;
411 		pad++;
412 	}
413 
414 	token = *new_length / 4;
415 	token = (~token << 16) | (token & 0x0000FFFF);
416 	token_le = cpu_to_le32(token);
417 
418 	memcpy(&nvp.nvram[*new_length], &token_le, sizeof(token_le));
419 	*new_length += sizeof(token_le);
420 
421 	return nvp.nvram;
422 }
423 
424 void brcmf_fw_nvram_free(void *nvram)
425 {
426 	kfree(nvram);
427 }
428 
429 struct brcmf_fw {
430 	struct device *dev;
431 	struct brcmf_fw_request *req;
432 	u32 curpos;
433 	void (*done)(struct device *dev, int err, struct brcmf_fw_request *req);
434 };
435 
436 static void brcmf_fw_request_done(const struct firmware *fw, void *ctx);
437 
438 #ifdef CONFIG_EFI
439 /* In some cases the EFI-var stored nvram contains "ccode=ALL" or "ccode=XV"
440  * to specify "worldwide" compatible settings, but these 2 ccode-s do not work
441  * properly. "ccode=ALL" causes channels 12 and 13 to not be available,
442  * "ccode=XV" causes all 5GHz channels to not be available. So we replace both
443  * with "ccode=X2" which allows channels 12+13 and 5Ghz channels in
444  * no-Initiate-Radiation mode. This means that we will never send on these
445  * channels without first having received valid wifi traffic on the channel.
446  */
447 static void brcmf_fw_fix_efi_nvram_ccode(char *data, unsigned long data_len)
448 {
449 	char *ccode;
450 
451 	ccode = strnstr((char *)data, "ccode=ALL", data_len);
452 	if (!ccode)
453 		ccode = strnstr((char *)data, "ccode=XV\r", data_len);
454 	if (!ccode)
455 		return;
456 
457 	ccode[6] = 'X';
458 	ccode[7] = '2';
459 	ccode[8] = '\r';
460 }
461 
462 static u8 *brcmf_fw_nvram_from_efi(size_t *data_len_ret)
463 {
464 	const u16 name[] = { 'n', 'v', 'r', 'a', 'm', 0 };
465 	struct efivar_entry *nvram_efivar;
466 	unsigned long data_len = 0;
467 	u8 *data = NULL;
468 	int err;
469 
470 	nvram_efivar = kzalloc(sizeof(*nvram_efivar), GFP_KERNEL);
471 	if (!nvram_efivar)
472 		return NULL;
473 
474 	memcpy(&nvram_efivar->var.VariableName, name, sizeof(name));
475 	nvram_efivar->var.VendorGuid = EFI_GUID(0x74b00bd9, 0x805a, 0x4d61,
476 						0xb5, 0x1f, 0x43, 0x26,
477 						0x81, 0x23, 0xd1, 0x13);
478 
479 	err = efivar_entry_size(nvram_efivar, &data_len);
480 	if (err)
481 		goto fail;
482 
483 	data = kmalloc(data_len, GFP_KERNEL);
484 	if (!data)
485 		goto fail;
486 
487 	err = efivar_entry_get(nvram_efivar, NULL, &data_len, data);
488 	if (err)
489 		goto fail;
490 
491 	brcmf_fw_fix_efi_nvram_ccode(data, data_len);
492 	brcmf_info("Using nvram EFI variable\n");
493 
494 	kfree(nvram_efivar);
495 	*data_len_ret = data_len;
496 	return data;
497 
498 fail:
499 	kfree(data);
500 	kfree(nvram_efivar);
501 	return NULL;
502 }
503 #else
504 static inline u8 *brcmf_fw_nvram_from_efi(size_t *data_len) { return NULL; }
505 #endif
506 
507 static void brcmf_fw_free_request(struct brcmf_fw_request *req)
508 {
509 	struct brcmf_fw_item *item;
510 	int i;
511 
512 	for (i = 0, item = &req->items[0]; i < req->n_items; i++, item++) {
513 		if (item->type == BRCMF_FW_TYPE_BINARY)
514 			release_firmware(item->binary);
515 		else if (item->type == BRCMF_FW_TYPE_NVRAM)
516 			brcmf_fw_nvram_free(item->nv_data.data);
517 	}
518 	kfree(req);
519 }
520 
521 static int brcmf_fw_request_nvram_done(const struct firmware *fw, void *ctx)
522 {
523 	struct brcmf_fw *fwctx = ctx;
524 	struct brcmf_fw_item *cur;
525 	bool free_bcm47xx_nvram = false;
526 	bool kfree_nvram = false;
527 	u32 nvram_length = 0;
528 	void *nvram = NULL;
529 	u8 *data = NULL;
530 	size_t data_len;
531 
532 	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(fwctx->dev));
533 
534 	cur = &fwctx->req->items[fwctx->curpos];
535 
536 	if (fw && fw->data) {
537 		data = (u8 *)fw->data;
538 		data_len = fw->size;
539 	} else {
540 		if ((data = bcm47xx_nvram_get_contents(&data_len)))
541 			free_bcm47xx_nvram = true;
542 		else if ((data = brcmf_fw_nvram_from_efi(&data_len)))
543 			kfree_nvram = true;
544 		else if (!(cur->flags & BRCMF_FW_REQF_OPTIONAL))
545 			goto fail;
546 	}
547 
548 	if (data)
549 		nvram = brcmf_fw_nvram_strip(data, data_len, &nvram_length,
550 					     fwctx->req->domain_nr,
551 					     fwctx->req->bus_nr);
552 
553 	if (free_bcm47xx_nvram)
554 		bcm47xx_nvram_release_contents(data);
555 	if (kfree_nvram)
556 		kfree(data);
557 
558 	release_firmware(fw);
559 	if (!nvram && !(cur->flags & BRCMF_FW_REQF_OPTIONAL))
560 		goto fail;
561 
562 	brcmf_dbg(TRACE, "nvram %p len %d\n", nvram, nvram_length);
563 	cur->nv_data.data = nvram;
564 	cur->nv_data.len = nvram_length;
565 	return 0;
566 
567 fail:
568 	return -ENOENT;
569 }
570 
571 static int brcmf_fw_complete_request(const struct firmware *fw,
572 				     struct brcmf_fw *fwctx)
573 {
574 	struct brcmf_fw_item *cur = &fwctx->req->items[fwctx->curpos];
575 	int ret = 0;
576 
577 	brcmf_dbg(TRACE, "firmware %s %sfound\n", cur->path, fw ? "" : "not ");
578 
579 	switch (cur->type) {
580 	case BRCMF_FW_TYPE_NVRAM:
581 		ret = brcmf_fw_request_nvram_done(fw, fwctx);
582 		break;
583 	case BRCMF_FW_TYPE_BINARY:
584 		if (fw)
585 			cur->binary = fw;
586 		else
587 			ret = -ENOENT;
588 		break;
589 	default:
590 		/* something fishy here so bail out early */
591 		brcmf_err("unknown fw type: %d\n", cur->type);
592 		release_firmware(fw);
593 		ret = -EINVAL;
594 	}
595 
596 	return (cur->flags & BRCMF_FW_REQF_OPTIONAL) ? 0 : ret;
597 }
598 
599 static int brcmf_fw_request_firmware(const struct firmware **fw,
600 				     struct brcmf_fw *fwctx)
601 {
602 	struct brcmf_fw_item *cur = &fwctx->req->items[fwctx->curpos];
603 	int ret;
604 
605 	/* nvram files are board-specific, first try a board-specific path */
606 	if (cur->type == BRCMF_FW_TYPE_NVRAM && fwctx->req->board_type) {
607 		char alt_path[BRCMF_FW_NAME_LEN];
608 
609 		strlcpy(alt_path, cur->path, BRCMF_FW_NAME_LEN);
610 		/* strip .txt at the end */
611 		alt_path[strlen(alt_path) - 4] = 0;
612 		strlcat(alt_path, ".", BRCMF_FW_NAME_LEN);
613 		strlcat(alt_path, fwctx->req->board_type, BRCMF_FW_NAME_LEN);
614 		strlcat(alt_path, ".txt", BRCMF_FW_NAME_LEN);
615 
616 		ret = request_firmware(fw, alt_path, fwctx->dev);
617 		if (ret == 0)
618 			return ret;
619 	}
620 
621 	return request_firmware(fw, cur->path, fwctx->dev);
622 }
623 
624 static void brcmf_fw_request_done(const struct firmware *fw, void *ctx)
625 {
626 	struct brcmf_fw *fwctx = ctx;
627 	int ret;
628 
629 	ret = brcmf_fw_complete_request(fw, fwctx);
630 
631 	while (ret == 0 && ++fwctx->curpos < fwctx->req->n_items) {
632 		brcmf_fw_request_firmware(&fw, fwctx);
633 		ret = brcmf_fw_complete_request(fw, ctx);
634 	}
635 
636 	if (ret) {
637 		brcmf_fw_free_request(fwctx->req);
638 		fwctx->req = NULL;
639 	}
640 	fwctx->done(fwctx->dev, ret, fwctx->req);
641 	kfree(fwctx);
642 }
643 
644 static bool brcmf_fw_request_is_valid(struct brcmf_fw_request *req)
645 {
646 	struct brcmf_fw_item *item;
647 	int i;
648 
649 	if (!req->n_items)
650 		return false;
651 
652 	for (i = 0, item = &req->items[0]; i < req->n_items; i++, item++) {
653 		if (!item->path)
654 			return false;
655 	}
656 	return true;
657 }
658 
659 int brcmf_fw_get_firmwares(struct device *dev, struct brcmf_fw_request *req,
660 			   void (*fw_cb)(struct device *dev, int err,
661 					 struct brcmf_fw_request *req))
662 {
663 	struct brcmf_fw_item *first = &req->items[0];
664 	struct brcmf_fw *fwctx;
665 	int ret;
666 
667 	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(dev));
668 	if (!fw_cb)
669 		return -EINVAL;
670 
671 	if (!brcmf_fw_request_is_valid(req))
672 		return -EINVAL;
673 
674 	fwctx = kzalloc(sizeof(*fwctx), GFP_KERNEL);
675 	if (!fwctx)
676 		return -ENOMEM;
677 
678 	fwctx->dev = dev;
679 	fwctx->req = req;
680 	fwctx->done = fw_cb;
681 
682 	ret = request_firmware_nowait(THIS_MODULE, true, first->path,
683 				      fwctx->dev, GFP_KERNEL, fwctx,
684 				      brcmf_fw_request_done);
685 	if (ret < 0)
686 		brcmf_fw_request_done(NULL, fwctx);
687 
688 	return 0;
689 }
690 
691 struct brcmf_fw_request *
692 brcmf_fw_alloc_request(u32 chip, u32 chiprev,
693 		       const struct brcmf_firmware_mapping mapping_table[],
694 		       u32 table_size, struct brcmf_fw_name *fwnames,
695 		       u32 n_fwnames)
696 {
697 	struct brcmf_fw_request *fwreq;
698 	char chipname[12];
699 	const char *mp_path;
700 	size_t mp_path_len;
701 	u32 i, j;
702 	char end = '\0';
703 
704 	for (i = 0; i < table_size; i++) {
705 		if (mapping_table[i].chipid == chip &&
706 		    mapping_table[i].revmask & BIT(chiprev))
707 			break;
708 	}
709 
710 	brcmf_chip_name(chip, chiprev, chipname, sizeof(chipname));
711 
712 	if (i == table_size) {
713 		brcmf_err("Unknown chip %s\n", chipname);
714 		return NULL;
715 	}
716 
717 	fwreq = kzalloc(struct_size(fwreq, items, n_fwnames), GFP_KERNEL);
718 	if (!fwreq)
719 		return NULL;
720 
721 	brcmf_info("using %s for chip %s\n",
722 		   mapping_table[i].fw_base, chipname);
723 
724 	mp_path = brcmf_mp_global.firmware_path;
725 	mp_path_len = strnlen(mp_path, BRCMF_FW_ALTPATH_LEN);
726 	if (mp_path_len)
727 		end = mp_path[mp_path_len - 1];
728 
729 	fwreq->n_items = n_fwnames;
730 
731 	for (j = 0; j < n_fwnames; j++) {
732 		fwreq->items[j].path = fwnames[j].path;
733 		fwnames[j].path[0] = '\0';
734 		/* check if firmware path is provided by module parameter */
735 		if (brcmf_mp_global.firmware_path[0] != '\0') {
736 			strlcpy(fwnames[j].path, mp_path,
737 				BRCMF_FW_NAME_LEN);
738 
739 			if (end != '/') {
740 				strlcat(fwnames[j].path, "/",
741 					BRCMF_FW_NAME_LEN);
742 			}
743 		}
744 		strlcat(fwnames[j].path, mapping_table[i].fw_base,
745 			BRCMF_FW_NAME_LEN);
746 		strlcat(fwnames[j].path, fwnames[j].extension,
747 			BRCMF_FW_NAME_LEN);
748 		fwreq->items[j].path = fwnames[j].path;
749 	}
750 
751 	return fwreq;
752 }
753