xref: /linux/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c (revision 16018c0d27eda6a7f69dafa750d23770fb46b00f)
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 		nvp->nvram_len = 0;
324 		return;
325 	}
326 
327 	/* Copy all valid entries, release old nvram and assign new one.
328 	 * Valid entries are of type pcie/X/Y/ where X = domain_nr and
329 	 * Y = bus_nr.
330 	 */
331 	snprintf(prefix, sizeof(prefix), "pcie/%d/%d/", domain_nr, bus_nr);
332 	len = strlen(prefix);
333 	i = 0;
334 	j = 0;
335 	while (i < nvp->nvram_len - len) {
336 		if (strncmp(&nvp->nvram[i], prefix, len) == 0) {
337 			i += len;
338 			if (strncmp(&nvp->nvram[i], "boardrev", 8) == 0)
339 				nvp->boardrev_found = true;
340 			while (nvp->nvram[i] != 0) {
341 				nvram[j] = nvp->nvram[i];
342 				i++;
343 				j++;
344 			}
345 			nvram[j] = 0;
346 			j++;
347 		}
348 		while (nvp->nvram[i] != 0)
349 			i++;
350 		i++;
351 	}
352 	kfree(nvp->nvram);
353 	nvp->nvram = nvram;
354 	nvp->nvram_len = j;
355 }
356 
357 static void brcmf_fw_add_defaults(struct nvram_parser *nvp)
358 {
359 	if (nvp->boardrev_found)
360 		return;
361 
362 	memcpy(&nvp->nvram[nvp->nvram_len], &BRCMF_FW_DEFAULT_BOARDREV,
363 	       strlen(BRCMF_FW_DEFAULT_BOARDREV));
364 	nvp->nvram_len += strlen(BRCMF_FW_DEFAULT_BOARDREV);
365 	nvp->nvram[nvp->nvram_len] = '\0';
366 	nvp->nvram_len++;
367 }
368 
369 /* brcmf_nvram_strip :Takes a buffer of "<var>=<value>\n" lines read from a fil
370  * and ending in a NUL. Removes carriage returns, empty lines, comment lines,
371  * and converts newlines to NULs. Shortens buffer as needed and pads with NULs.
372  * End of buffer is completed with token identifying length of buffer.
373  */
374 static void *brcmf_fw_nvram_strip(const u8 *data, size_t data_len,
375 				  u32 *new_length, u16 domain_nr, u16 bus_nr)
376 {
377 	struct nvram_parser nvp;
378 	u32 pad;
379 	u32 token;
380 	__le32 token_le;
381 
382 	if (brcmf_init_nvram_parser(&nvp, data, data_len) < 0)
383 		return NULL;
384 
385 	while (nvp.pos < data_len) {
386 		nvp.state = nv_parser_states[nvp.state](&nvp);
387 		if (nvp.state == END)
388 			break;
389 	}
390 	if (nvp.multi_dev_v1) {
391 		nvp.boardrev_found = false;
392 		brcmf_fw_strip_multi_v1(&nvp, domain_nr, bus_nr);
393 	} else if (nvp.multi_dev_v2) {
394 		nvp.boardrev_found = false;
395 		brcmf_fw_strip_multi_v2(&nvp, domain_nr, bus_nr);
396 	}
397 
398 	if (nvp.nvram_len == 0) {
399 		kfree(nvp.nvram);
400 		return NULL;
401 	}
402 
403 	brcmf_fw_add_defaults(&nvp);
404 
405 	pad = nvp.nvram_len;
406 	*new_length = roundup(nvp.nvram_len + 1, 4);
407 	while (pad != *new_length) {
408 		nvp.nvram[pad] = 0;
409 		pad++;
410 	}
411 
412 	token = *new_length / 4;
413 	token = (~token << 16) | (token & 0x0000FFFF);
414 	token_le = cpu_to_le32(token);
415 
416 	memcpy(&nvp.nvram[*new_length], &token_le, sizeof(token_le));
417 	*new_length += sizeof(token_le);
418 
419 	return nvp.nvram;
420 }
421 
422 void brcmf_fw_nvram_free(void *nvram)
423 {
424 	kfree(nvram);
425 }
426 
427 struct brcmf_fw {
428 	struct device *dev;
429 	struct brcmf_fw_request *req;
430 	u32 curpos;
431 	void (*done)(struct device *dev, int err, struct brcmf_fw_request *req);
432 };
433 
434 #ifdef CONFIG_EFI
435 /* In some cases the EFI-var stored nvram contains "ccode=ALL" or "ccode=XV"
436  * to specify "worldwide" compatible settings, but these 2 ccode-s do not work
437  * properly. "ccode=ALL" causes channels 12 and 13 to not be available,
438  * "ccode=XV" causes all 5GHz channels to not be available. So we replace both
439  * with "ccode=X2" which allows channels 12+13 and 5Ghz channels in
440  * no-Initiate-Radiation mode. This means that we will never send on these
441  * channels without first having received valid wifi traffic on the channel.
442  */
443 static void brcmf_fw_fix_efi_nvram_ccode(char *data, unsigned long data_len)
444 {
445 	char *ccode;
446 
447 	ccode = strnstr((char *)data, "ccode=ALL", data_len);
448 	if (!ccode)
449 		ccode = strnstr((char *)data, "ccode=XV\r", data_len);
450 	if (!ccode)
451 		return;
452 
453 	ccode[6] = 'X';
454 	ccode[7] = '2';
455 	ccode[8] = '\r';
456 }
457 
458 static u8 *brcmf_fw_nvram_from_efi(size_t *data_len_ret)
459 {
460 	const u16 name[] = { 'n', 'v', 'r', 'a', 'm', 0 };
461 	struct efivar_entry *nvram_efivar;
462 	unsigned long data_len = 0;
463 	u8 *data = NULL;
464 	int err;
465 
466 	nvram_efivar = kzalloc(sizeof(*nvram_efivar), GFP_KERNEL);
467 	if (!nvram_efivar)
468 		return NULL;
469 
470 	memcpy(&nvram_efivar->var.VariableName, name, sizeof(name));
471 	nvram_efivar->var.VendorGuid = EFI_GUID(0x74b00bd9, 0x805a, 0x4d61,
472 						0xb5, 0x1f, 0x43, 0x26,
473 						0x81, 0x23, 0xd1, 0x13);
474 
475 	err = efivar_entry_size(nvram_efivar, &data_len);
476 	if (err)
477 		goto fail;
478 
479 	data = kmalloc(data_len, GFP_KERNEL);
480 	if (!data)
481 		goto fail;
482 
483 	err = efivar_entry_get(nvram_efivar, NULL, &data_len, data);
484 	if (err)
485 		goto fail;
486 
487 	brcmf_fw_fix_efi_nvram_ccode(data, data_len);
488 	brcmf_info("Using nvram EFI variable\n");
489 
490 	kfree(nvram_efivar);
491 	*data_len_ret = data_len;
492 	return data;
493 
494 fail:
495 	kfree(data);
496 	kfree(nvram_efivar);
497 	return NULL;
498 }
499 #else
500 static inline u8 *brcmf_fw_nvram_from_efi(size_t *data_len) { return NULL; }
501 #endif
502 
503 static void brcmf_fw_free_request(struct brcmf_fw_request *req)
504 {
505 	struct brcmf_fw_item *item;
506 	int i;
507 
508 	for (i = 0, item = &req->items[0]; i < req->n_items; i++, item++) {
509 		if (item->type == BRCMF_FW_TYPE_BINARY)
510 			release_firmware(item->binary);
511 		else if (item->type == BRCMF_FW_TYPE_NVRAM)
512 			brcmf_fw_nvram_free(item->nv_data.data);
513 	}
514 	kfree(req);
515 }
516 
517 static int brcmf_fw_request_nvram_done(const struct firmware *fw, void *ctx)
518 {
519 	struct brcmf_fw *fwctx = ctx;
520 	struct brcmf_fw_item *cur;
521 	bool free_bcm47xx_nvram = false;
522 	bool kfree_nvram = false;
523 	u32 nvram_length = 0;
524 	void *nvram = NULL;
525 	u8 *data = NULL;
526 	size_t data_len;
527 
528 	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(fwctx->dev));
529 
530 	cur = &fwctx->req->items[fwctx->curpos];
531 
532 	if (fw && fw->data) {
533 		data = (u8 *)fw->data;
534 		data_len = fw->size;
535 	} else {
536 		if ((data = bcm47xx_nvram_get_contents(&data_len)))
537 			free_bcm47xx_nvram = true;
538 		else if ((data = brcmf_fw_nvram_from_efi(&data_len)))
539 			kfree_nvram = true;
540 		else if (!(cur->flags & BRCMF_FW_REQF_OPTIONAL))
541 			goto fail;
542 	}
543 
544 	if (data)
545 		nvram = brcmf_fw_nvram_strip(data, data_len, &nvram_length,
546 					     fwctx->req->domain_nr,
547 					     fwctx->req->bus_nr);
548 
549 	if (free_bcm47xx_nvram)
550 		bcm47xx_nvram_release_contents(data);
551 	if (kfree_nvram)
552 		kfree(data);
553 
554 	release_firmware(fw);
555 	if (!nvram && !(cur->flags & BRCMF_FW_REQF_OPTIONAL))
556 		goto fail;
557 
558 	brcmf_dbg(TRACE, "nvram %p len %d\n", nvram, nvram_length);
559 	cur->nv_data.data = nvram;
560 	cur->nv_data.len = nvram_length;
561 	return 0;
562 
563 fail:
564 	return -ENOENT;
565 }
566 
567 static int brcmf_fw_complete_request(const struct firmware *fw,
568 				     struct brcmf_fw *fwctx)
569 {
570 	struct brcmf_fw_item *cur = &fwctx->req->items[fwctx->curpos];
571 	int ret = 0;
572 
573 	brcmf_dbg(TRACE, "firmware %s %sfound\n", cur->path, fw ? "" : "not ");
574 
575 	switch (cur->type) {
576 	case BRCMF_FW_TYPE_NVRAM:
577 		ret = brcmf_fw_request_nvram_done(fw, fwctx);
578 		break;
579 	case BRCMF_FW_TYPE_BINARY:
580 		if (fw)
581 			cur->binary = fw;
582 		else
583 			ret = -ENOENT;
584 		break;
585 	default:
586 		/* something fishy here so bail out early */
587 		brcmf_err("unknown fw type: %d\n", cur->type);
588 		release_firmware(fw);
589 		ret = -EINVAL;
590 	}
591 
592 	return (cur->flags & BRCMF_FW_REQF_OPTIONAL) ? 0 : ret;
593 }
594 
595 static char *brcm_alt_fw_path(const char *path, const char *board_type)
596 {
597 	char alt_path[BRCMF_FW_NAME_LEN];
598 	char suffix[5];
599 
600 	strscpy(alt_path, path, BRCMF_FW_NAME_LEN);
601 	/* At least one character + suffix */
602 	if (strlen(alt_path) < 5)
603 		return NULL;
604 
605 	/* strip .txt or .bin at the end */
606 	strscpy(suffix, alt_path + strlen(alt_path) - 4, 5);
607 	alt_path[strlen(alt_path) - 4] = 0;
608 	strlcat(alt_path, ".", BRCMF_FW_NAME_LEN);
609 	strlcat(alt_path, board_type, BRCMF_FW_NAME_LEN);
610 	strlcat(alt_path, suffix, BRCMF_FW_NAME_LEN);
611 
612 	return kstrdup(alt_path, GFP_KERNEL);
613 }
614 
615 static int brcmf_fw_request_firmware(const struct firmware **fw,
616 				     struct brcmf_fw *fwctx)
617 {
618 	struct brcmf_fw_item *cur = &fwctx->req->items[fwctx->curpos];
619 	int ret;
620 
621 	/* Files can be board-specific, first try a board-specific path */
622 	if (cur->type == BRCMF_FW_TYPE_NVRAM && fwctx->req->board_type) {
623 		char *alt_path;
624 
625 		alt_path = brcm_alt_fw_path(cur->path, fwctx->req->board_type);
626 		if (!alt_path)
627 			goto fallback;
628 
629 		ret = request_firmware(fw, alt_path, fwctx->dev);
630 		kfree(alt_path);
631 		if (ret == 0)
632 			return ret;
633 	}
634 
635 fallback:
636 	return request_firmware(fw, cur->path, fwctx->dev);
637 }
638 
639 static void brcmf_fw_request_done(const struct firmware *fw, void *ctx)
640 {
641 	struct brcmf_fw *fwctx = ctx;
642 	int ret;
643 
644 	ret = brcmf_fw_complete_request(fw, fwctx);
645 
646 	while (ret == 0 && ++fwctx->curpos < fwctx->req->n_items) {
647 		brcmf_fw_request_firmware(&fw, fwctx);
648 		ret = brcmf_fw_complete_request(fw, ctx);
649 	}
650 
651 	if (ret) {
652 		brcmf_fw_free_request(fwctx->req);
653 		fwctx->req = NULL;
654 	}
655 	fwctx->done(fwctx->dev, ret, fwctx->req);
656 	kfree(fwctx);
657 }
658 
659 static void brcmf_fw_request_done_alt_path(const struct firmware *fw, void *ctx)
660 {
661 	struct brcmf_fw *fwctx = ctx;
662 	struct brcmf_fw_item *first = &fwctx->req->items[0];
663 	int ret = 0;
664 
665 	/* Fall back to canonical path if board firmware not found */
666 	if (!fw)
667 		ret = request_firmware_nowait(THIS_MODULE, true, first->path,
668 					      fwctx->dev, GFP_KERNEL, fwctx,
669 					      brcmf_fw_request_done);
670 
671 	if (fw || ret < 0)
672 		brcmf_fw_request_done(fw, ctx);
673 }
674 
675 static bool brcmf_fw_request_is_valid(struct brcmf_fw_request *req)
676 {
677 	struct brcmf_fw_item *item;
678 	int i;
679 
680 	if (!req->n_items)
681 		return false;
682 
683 	for (i = 0, item = &req->items[0]; i < req->n_items; i++, item++) {
684 		if (!item->path)
685 			return false;
686 	}
687 	return true;
688 }
689 
690 int brcmf_fw_get_firmwares(struct device *dev, struct brcmf_fw_request *req,
691 			   void (*fw_cb)(struct device *dev, int err,
692 					 struct brcmf_fw_request *req))
693 {
694 	struct brcmf_fw_item *first = &req->items[0];
695 	struct brcmf_fw *fwctx;
696 	char *alt_path;
697 	int ret;
698 
699 	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(dev));
700 	if (!fw_cb)
701 		return -EINVAL;
702 
703 	if (!brcmf_fw_request_is_valid(req))
704 		return -EINVAL;
705 
706 	fwctx = kzalloc(sizeof(*fwctx), GFP_KERNEL);
707 	if (!fwctx)
708 		return -ENOMEM;
709 
710 	fwctx->dev = dev;
711 	fwctx->req = req;
712 	fwctx->done = fw_cb;
713 
714 	/* First try alternative board-specific path if any */
715 	alt_path = brcm_alt_fw_path(first->path, fwctx->req->board_type);
716 	if (alt_path) {
717 		ret = request_firmware_nowait(THIS_MODULE, true, alt_path,
718 					      fwctx->dev, GFP_KERNEL, fwctx,
719 					      brcmf_fw_request_done_alt_path);
720 		kfree(alt_path);
721 	} else {
722 		ret = request_firmware_nowait(THIS_MODULE, true, first->path,
723 					      fwctx->dev, GFP_KERNEL, fwctx,
724 					      brcmf_fw_request_done);
725 	}
726 	if (ret < 0)
727 		brcmf_fw_request_done(NULL, fwctx);
728 
729 	return 0;
730 }
731 
732 struct brcmf_fw_request *
733 brcmf_fw_alloc_request(u32 chip, u32 chiprev,
734 		       const struct brcmf_firmware_mapping mapping_table[],
735 		       u32 table_size, struct brcmf_fw_name *fwnames,
736 		       u32 n_fwnames)
737 {
738 	struct brcmf_fw_request *fwreq;
739 	char chipname[12];
740 	const char *mp_path;
741 	size_t mp_path_len;
742 	u32 i, j;
743 	char end = '\0';
744 
745 	for (i = 0; i < table_size; i++) {
746 		if (mapping_table[i].chipid == chip &&
747 		    mapping_table[i].revmask & BIT(chiprev))
748 			break;
749 	}
750 
751 	brcmf_chip_name(chip, chiprev, chipname, sizeof(chipname));
752 
753 	if (i == table_size) {
754 		brcmf_err("Unknown chip %s\n", chipname);
755 		return NULL;
756 	}
757 
758 	fwreq = kzalloc(struct_size(fwreq, items, n_fwnames), GFP_KERNEL);
759 	if (!fwreq)
760 		return NULL;
761 
762 	brcmf_info("using %s for chip %s\n",
763 		   mapping_table[i].fw_base, chipname);
764 
765 	mp_path = brcmf_mp_global.firmware_path;
766 	mp_path_len = strnlen(mp_path, BRCMF_FW_ALTPATH_LEN);
767 	if (mp_path_len)
768 		end = mp_path[mp_path_len - 1];
769 
770 	fwreq->n_items = n_fwnames;
771 
772 	for (j = 0; j < n_fwnames; j++) {
773 		fwreq->items[j].path = fwnames[j].path;
774 		fwnames[j].path[0] = '\0';
775 		/* check if firmware path is provided by module parameter */
776 		if (brcmf_mp_global.firmware_path[0] != '\0') {
777 			strlcpy(fwnames[j].path, mp_path,
778 				BRCMF_FW_NAME_LEN);
779 
780 			if (end != '/') {
781 				strlcat(fwnames[j].path, "/",
782 					BRCMF_FW_NAME_LEN);
783 			}
784 		}
785 		strlcat(fwnames[j].path, mapping_table[i].fw_base,
786 			BRCMF_FW_NAME_LEN);
787 		strlcat(fwnames[j].path, fwnames[j].extension,
788 			BRCMF_FW_NAME_LEN);
789 		fwreq->items[j].path = fwnames[j].path;
790 	}
791 
792 	return fwreq;
793 }
794