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 	/* Add space for properties we may add */
211 	size += strlen(BRCMF_FW_DEFAULT_BOARDREV) + 1;
212 	/* Alloc for extra 0 byte + roundup by 4 + length field */
213 	size += 1 + 3 + sizeof(u32);
214 	nvp->nvram = kzalloc(size, GFP_KERNEL);
215 	if (!nvp->nvram)
216 		return -ENOMEM;
217 
218 	nvp->line = 1;
219 	nvp->column = 1;
220 	return 0;
221 }
222 
223 /* brcmf_fw_strip_multi_v1 :Some nvram files contain settings for multiple
224  * devices. Strip it down for one device, use domain_nr/bus_nr to determine
225  * which data is to be returned. v1 is the version where nvram is stored
226  * compressed and "devpath" maps to index for valid entries.
227  */
228 static void brcmf_fw_strip_multi_v1(struct nvram_parser *nvp, u16 domain_nr,
229 				    u16 bus_nr)
230 {
231 	/* Device path with a leading '=' key-value separator */
232 	char pci_path[] = "=pci/?/?";
233 	size_t pci_len;
234 	char pcie_path[] = "=pcie/?/?";
235 	size_t pcie_len;
236 
237 	u32 i, j;
238 	bool found;
239 	u8 *nvram;
240 	u8 id;
241 
242 	nvram = kzalloc(nvp->nvram_len + 1 + 3 + sizeof(u32), GFP_KERNEL);
243 	if (!nvram)
244 		goto fail;
245 
246 	/* min length: devpath0=pcie/1/4/ + 0:x=y */
247 	if (nvp->nvram_len < BRCMF_FW_NVRAM_DEVPATH_LEN + 6)
248 		goto fail;
249 
250 	/* First search for the devpathX and see if it is the configuration
251 	 * for domain_nr/bus_nr. Search complete nvp
252 	 */
253 	snprintf(pci_path, sizeof(pci_path), "=pci/%d/%d", domain_nr,
254 		 bus_nr);
255 	pci_len = strlen(pci_path);
256 	snprintf(pcie_path, sizeof(pcie_path), "=pcie/%d/%d", domain_nr,
257 		 bus_nr);
258 	pcie_len = strlen(pcie_path);
259 	found = false;
260 	i = 0;
261 	while (i < nvp->nvram_len - BRCMF_FW_NVRAM_DEVPATH_LEN) {
262 		/* Format: devpathX=pcie/Y/Z/
263 		 * Y = domain_nr, Z = bus_nr, X = virtual ID
264 		 */
265 		if (strncmp(&nvp->nvram[i], "devpath", 7) == 0 &&
266 		    (!strncmp(&nvp->nvram[i + 8], pci_path, pci_len) ||
267 		     !strncmp(&nvp->nvram[i + 8], pcie_path, pcie_len))) {
268 			id = nvp->nvram[i + 7] - '0';
269 			found = true;
270 			break;
271 		}
272 		while (nvp->nvram[i] != 0)
273 			i++;
274 		i++;
275 	}
276 	if (!found)
277 		goto fail;
278 
279 	/* Now copy all valid entries, release old nvram and assign new one */
280 	i = 0;
281 	j = 0;
282 	while (i < nvp->nvram_len) {
283 		if ((nvp->nvram[i] - '0' == id) && (nvp->nvram[i + 1] == ':')) {
284 			i += 2;
285 			if (strncmp(&nvp->nvram[i], "boardrev", 8) == 0)
286 				nvp->boardrev_found = true;
287 			while (nvp->nvram[i] != 0) {
288 				nvram[j] = nvp->nvram[i];
289 				i++;
290 				j++;
291 			}
292 			nvram[j] = 0;
293 			j++;
294 		}
295 		while (nvp->nvram[i] != 0)
296 			i++;
297 		i++;
298 	}
299 	kfree(nvp->nvram);
300 	nvp->nvram = nvram;
301 	nvp->nvram_len = j;
302 	return;
303 
304 fail:
305 	kfree(nvram);
306 	nvp->nvram_len = 0;
307 }
308 
309 /* brcmf_fw_strip_multi_v2 :Some nvram files contain settings for multiple
310  * devices. Strip it down for one device, use domain_nr/bus_nr to determine
311  * which data is to be returned. v2 is the version where nvram is stored
312  * uncompressed, all relevant valid entries are identified by
313  * pcie/domain_nr/bus_nr:
314  */
315 static void brcmf_fw_strip_multi_v2(struct nvram_parser *nvp, u16 domain_nr,
316 				    u16 bus_nr)
317 {
318 	char prefix[BRCMF_FW_NVRAM_PCIEDEV_LEN];
319 	size_t len;
320 	u32 i, j;
321 	u8 *nvram;
322 
323 	nvram = kzalloc(nvp->nvram_len + 1 + 3 + sizeof(u32), GFP_KERNEL);
324 	if (!nvram) {
325 		nvp->nvram_len = 0;
326 		return;
327 	}
328 
329 	/* Copy all valid entries, release old nvram and assign new one.
330 	 * Valid entries are of type pcie/X/Y/ where X = domain_nr and
331 	 * Y = bus_nr.
332 	 */
333 	snprintf(prefix, sizeof(prefix), "pcie/%d/%d/", domain_nr, bus_nr);
334 	len = strlen(prefix);
335 	i = 0;
336 	j = 0;
337 	while (i < nvp->nvram_len - len) {
338 		if (strncmp(&nvp->nvram[i], prefix, len) == 0) {
339 			i += len;
340 			if (strncmp(&nvp->nvram[i], "boardrev", 8) == 0)
341 				nvp->boardrev_found = true;
342 			while (nvp->nvram[i] != 0) {
343 				nvram[j] = nvp->nvram[i];
344 				i++;
345 				j++;
346 			}
347 			nvram[j] = 0;
348 			j++;
349 		}
350 		while (nvp->nvram[i] != 0)
351 			i++;
352 		i++;
353 	}
354 	kfree(nvp->nvram);
355 	nvp->nvram = nvram;
356 	nvp->nvram_len = j;
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 #ifdef CONFIG_EFI
437 /* In some cases the EFI-var stored nvram contains "ccode=ALL" or "ccode=XV"
438  * to specify "worldwide" compatible settings, but these 2 ccode-s do not work
439  * properly. "ccode=ALL" causes channels 12 and 13 to not be available,
440  * "ccode=XV" causes all 5GHz channels to not be available. So we replace both
441  * with "ccode=X2" which allows channels 12+13 and 5Ghz channels in
442  * no-Initiate-Radiation mode. This means that we will never send on these
443  * channels without first having received valid wifi traffic on the channel.
444  */
445 static void brcmf_fw_fix_efi_nvram_ccode(char *data, unsigned long data_len)
446 {
447 	char *ccode;
448 
449 	ccode = strnstr((char *)data, "ccode=ALL", data_len);
450 	if (!ccode)
451 		ccode = strnstr((char *)data, "ccode=XV\r", data_len);
452 	if (!ccode)
453 		return;
454 
455 	ccode[6] = 'X';
456 	ccode[7] = '2';
457 	ccode[8] = '\r';
458 }
459 
460 static u8 *brcmf_fw_nvram_from_efi(size_t *data_len_ret)
461 {
462 	efi_guid_t guid = EFI_GUID(0x74b00bd9, 0x805a, 0x4d61, 0xb5, 0x1f,
463 				   0x43, 0x26, 0x81, 0x23, 0xd1, 0x13);
464 	unsigned long data_len = 0;
465 	efi_status_t status;
466 	u8 *data = NULL;
467 
468 	if (!efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE))
469 		return NULL;
470 
471 	status = efi.get_variable(L"nvram", &guid, NULL, &data_len, NULL);
472 	if (status != EFI_BUFFER_TOO_SMALL)
473 		goto fail;
474 
475 	data = kmalloc(data_len, GFP_KERNEL);
476 	if (!data)
477 		goto fail;
478 
479 	status = efi.get_variable(L"nvram", &guid, NULL, &data_len, data);
480 	if (status != EFI_SUCCESS)
481 		goto fail;
482 
483 	brcmf_fw_fix_efi_nvram_ccode(data, data_len);
484 	brcmf_info("Using nvram EFI variable\n");
485 
486 	*data_len_ret = data_len;
487 	return data;
488 fail:
489 	kfree(data);
490 	return NULL;
491 }
492 #else
493 static inline u8 *brcmf_fw_nvram_from_efi(size_t *data_len) { return NULL; }
494 #endif
495 
496 static void brcmf_fw_free_request(struct brcmf_fw_request *req)
497 {
498 	struct brcmf_fw_item *item;
499 	int i;
500 
501 	for (i = 0, item = &req->items[0]; i < req->n_items; i++, item++) {
502 		if (item->type == BRCMF_FW_TYPE_BINARY)
503 			release_firmware(item->binary);
504 		else if (item->type == BRCMF_FW_TYPE_NVRAM)
505 			brcmf_fw_nvram_free(item->nv_data.data);
506 	}
507 	kfree(req);
508 }
509 
510 static int brcmf_fw_request_nvram_done(const struct firmware *fw, void *ctx)
511 {
512 	struct brcmf_fw *fwctx = ctx;
513 	struct brcmf_fw_item *cur;
514 	bool free_bcm47xx_nvram = false;
515 	bool kfree_nvram = false;
516 	u32 nvram_length = 0;
517 	void *nvram = NULL;
518 	u8 *data = NULL;
519 	size_t data_len;
520 
521 	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(fwctx->dev));
522 
523 	cur = &fwctx->req->items[fwctx->curpos];
524 
525 	if (fw && fw->data) {
526 		data = (u8 *)fw->data;
527 		data_len = fw->size;
528 	} else {
529 		if ((data = bcm47xx_nvram_get_contents(&data_len)))
530 			free_bcm47xx_nvram = true;
531 		else if ((data = brcmf_fw_nvram_from_efi(&data_len)))
532 			kfree_nvram = true;
533 		else if (!(cur->flags & BRCMF_FW_REQF_OPTIONAL))
534 			goto fail;
535 	}
536 
537 	if (data)
538 		nvram = brcmf_fw_nvram_strip(data, data_len, &nvram_length,
539 					     fwctx->req->domain_nr,
540 					     fwctx->req->bus_nr);
541 
542 	if (free_bcm47xx_nvram)
543 		bcm47xx_nvram_release_contents(data);
544 	if (kfree_nvram)
545 		kfree(data);
546 
547 	release_firmware(fw);
548 	if (!nvram && !(cur->flags & BRCMF_FW_REQF_OPTIONAL))
549 		goto fail;
550 
551 	brcmf_dbg(TRACE, "nvram %p len %d\n", nvram, nvram_length);
552 	cur->nv_data.data = nvram;
553 	cur->nv_data.len = nvram_length;
554 	return 0;
555 
556 fail:
557 	return -ENOENT;
558 }
559 
560 static int brcmf_fw_complete_request(const struct firmware *fw,
561 				     struct brcmf_fw *fwctx)
562 {
563 	struct brcmf_fw_item *cur = &fwctx->req->items[fwctx->curpos];
564 	int ret = 0;
565 
566 	brcmf_dbg(TRACE, "firmware %s %sfound\n", cur->path, fw ? "" : "not ");
567 
568 	switch (cur->type) {
569 	case BRCMF_FW_TYPE_NVRAM:
570 		ret = brcmf_fw_request_nvram_done(fw, fwctx);
571 		break;
572 	case BRCMF_FW_TYPE_BINARY:
573 		if (fw)
574 			cur->binary = fw;
575 		else
576 			ret = -ENOENT;
577 		break;
578 	default:
579 		/* something fishy here so bail out early */
580 		brcmf_err("unknown fw type: %d\n", cur->type);
581 		release_firmware(fw);
582 		ret = -EINVAL;
583 	}
584 
585 	return (cur->flags & BRCMF_FW_REQF_OPTIONAL) ? 0 : ret;
586 }
587 
588 static char *brcm_alt_fw_path(const char *path, const char *board_type)
589 {
590 	char alt_path[BRCMF_FW_NAME_LEN];
591 	char suffix[5];
592 
593 	strscpy(alt_path, path, BRCMF_FW_NAME_LEN);
594 	/* At least one character + suffix */
595 	if (strlen(alt_path) < 5)
596 		return NULL;
597 
598 	/* strip .txt or .bin at the end */
599 	strscpy(suffix, alt_path + strlen(alt_path) - 4, 5);
600 	alt_path[strlen(alt_path) - 4] = 0;
601 	strlcat(alt_path, ".", BRCMF_FW_NAME_LEN);
602 	strlcat(alt_path, board_type, BRCMF_FW_NAME_LEN);
603 	strlcat(alt_path, suffix, BRCMF_FW_NAME_LEN);
604 
605 	return kstrdup(alt_path, GFP_KERNEL);
606 }
607 
608 static int brcmf_fw_request_firmware(const struct firmware **fw,
609 				     struct brcmf_fw *fwctx)
610 {
611 	struct brcmf_fw_item *cur = &fwctx->req->items[fwctx->curpos];
612 	int ret;
613 
614 	/* Files can be board-specific, first try a board-specific path */
615 	if (cur->type == BRCMF_FW_TYPE_NVRAM && fwctx->req->board_type) {
616 		char *alt_path;
617 
618 		alt_path = brcm_alt_fw_path(cur->path, fwctx->req->board_type);
619 		if (!alt_path)
620 			goto fallback;
621 
622 		ret = request_firmware(fw, alt_path, fwctx->dev);
623 		kfree(alt_path);
624 		if (ret == 0)
625 			return ret;
626 	}
627 
628 fallback:
629 	return request_firmware(fw, cur->path, fwctx->dev);
630 }
631 
632 static void brcmf_fw_request_done(const struct firmware *fw, void *ctx)
633 {
634 	struct brcmf_fw *fwctx = ctx;
635 	int ret;
636 
637 	ret = brcmf_fw_complete_request(fw, fwctx);
638 
639 	while (ret == 0 && ++fwctx->curpos < fwctx->req->n_items) {
640 		brcmf_fw_request_firmware(&fw, fwctx);
641 		ret = brcmf_fw_complete_request(fw, ctx);
642 	}
643 
644 	if (ret) {
645 		brcmf_fw_free_request(fwctx->req);
646 		fwctx->req = NULL;
647 	}
648 	fwctx->done(fwctx->dev, ret, fwctx->req);
649 	kfree(fwctx);
650 }
651 
652 static void brcmf_fw_request_done_alt_path(const struct firmware *fw, void *ctx)
653 {
654 	struct brcmf_fw *fwctx = ctx;
655 	struct brcmf_fw_item *first = &fwctx->req->items[0];
656 	int ret = 0;
657 
658 	/* Fall back to canonical path if board firmware not found */
659 	if (!fw)
660 		ret = request_firmware_nowait(THIS_MODULE, true, first->path,
661 					      fwctx->dev, GFP_KERNEL, fwctx,
662 					      brcmf_fw_request_done);
663 
664 	if (fw || ret < 0)
665 		brcmf_fw_request_done(fw, ctx);
666 }
667 
668 static bool brcmf_fw_request_is_valid(struct brcmf_fw_request *req)
669 {
670 	struct brcmf_fw_item *item;
671 	int i;
672 
673 	if (!req->n_items)
674 		return false;
675 
676 	for (i = 0, item = &req->items[0]; i < req->n_items; i++, item++) {
677 		if (!item->path)
678 			return false;
679 	}
680 	return true;
681 }
682 
683 int brcmf_fw_get_firmwares(struct device *dev, struct brcmf_fw_request *req,
684 			   void (*fw_cb)(struct device *dev, int err,
685 					 struct brcmf_fw_request *req))
686 {
687 	struct brcmf_fw_item *first = &req->items[0];
688 	struct brcmf_fw *fwctx;
689 	char *alt_path = NULL;
690 	int ret;
691 
692 	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(dev));
693 	if (!fw_cb)
694 		return -EINVAL;
695 
696 	if (!brcmf_fw_request_is_valid(req))
697 		return -EINVAL;
698 
699 	fwctx = kzalloc(sizeof(*fwctx), GFP_KERNEL);
700 	if (!fwctx)
701 		return -ENOMEM;
702 
703 	fwctx->dev = dev;
704 	fwctx->req = req;
705 	fwctx->done = fw_cb;
706 
707 	/* First try alternative board-specific path if any */
708 	if (fwctx->req->board_type)
709 		alt_path = brcm_alt_fw_path(first->path,
710 					    fwctx->req->board_type);
711 	if (alt_path) {
712 		ret = request_firmware_nowait(THIS_MODULE, true, alt_path,
713 					      fwctx->dev, GFP_KERNEL, fwctx,
714 					      brcmf_fw_request_done_alt_path);
715 		kfree(alt_path);
716 	} else {
717 		ret = request_firmware_nowait(THIS_MODULE, true, first->path,
718 					      fwctx->dev, GFP_KERNEL, fwctx,
719 					      brcmf_fw_request_done);
720 	}
721 	if (ret < 0)
722 		brcmf_fw_request_done(NULL, fwctx);
723 
724 	return 0;
725 }
726 
727 struct brcmf_fw_request *
728 brcmf_fw_alloc_request(u32 chip, u32 chiprev,
729 		       const struct brcmf_firmware_mapping mapping_table[],
730 		       u32 table_size, struct brcmf_fw_name *fwnames,
731 		       u32 n_fwnames)
732 {
733 	struct brcmf_fw_request *fwreq;
734 	char chipname[12];
735 	const char *mp_path;
736 	size_t mp_path_len;
737 	u32 i, j;
738 	char end = '\0';
739 
740 	for (i = 0; i < table_size; i++) {
741 		if (mapping_table[i].chipid == chip &&
742 		    mapping_table[i].revmask & BIT(chiprev))
743 			break;
744 	}
745 
746 	brcmf_chip_name(chip, chiprev, chipname, sizeof(chipname));
747 
748 	if (i == table_size) {
749 		brcmf_err("Unknown chip %s\n", chipname);
750 		return NULL;
751 	}
752 
753 	fwreq = kzalloc(struct_size(fwreq, items, n_fwnames), GFP_KERNEL);
754 	if (!fwreq)
755 		return NULL;
756 
757 	brcmf_info("using %s for chip %s\n",
758 		   mapping_table[i].fw_base, chipname);
759 
760 	mp_path = brcmf_mp_global.firmware_path;
761 	mp_path_len = strnlen(mp_path, BRCMF_FW_ALTPATH_LEN);
762 	if (mp_path_len)
763 		end = mp_path[mp_path_len - 1];
764 
765 	fwreq->n_items = n_fwnames;
766 
767 	for (j = 0; j < n_fwnames; j++) {
768 		fwreq->items[j].path = fwnames[j].path;
769 		fwnames[j].path[0] = '\0';
770 		/* check if firmware path is provided by module parameter */
771 		if (brcmf_mp_global.firmware_path[0] != '\0') {
772 			strscpy(fwnames[j].path, mp_path,
773 				BRCMF_FW_NAME_LEN);
774 
775 			if (end != '/') {
776 				strlcat(fwnames[j].path, "/",
777 					BRCMF_FW_NAME_LEN);
778 			}
779 		}
780 		strlcat(fwnames[j].path, mapping_table[i].fw_base,
781 			BRCMF_FW_NAME_LEN);
782 		strlcat(fwnames[j].path, fwnames[j].extension,
783 			BRCMF_FW_NAME_LEN);
784 		fwreq->items[j].path = fwnames[j].path;
785 	}
786 
787 	return fwreq;
788 }
789