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
25enum 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 */
48struct 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 */
68static 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
78static bool is_whitespace(char c)
79{
80	return (c == ' ' || c == '\r' || c == '\n' || c == '\t');
81}
82
83static 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);
100proceed:
101	nvp->column++;
102	nvp->pos++;
103	return IDLE;
104}
105
106static 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
135static enum nvram_parser_state
136brcmf_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
163static enum nvram_parser_state
164brcmf_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
183static enum nvram_parser_state brcmf_nvram_handle_end(struct nvram_parser *nvp)
184{
185	/* final state */
186	return END;
187}
188
189static 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
198static 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 */
228static 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
304fail:
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 */
315static 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		goto fail;
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	return;
356fail:
357	kfree(nvram);
358	nvp->nvram_len = 0;
359}
360
361static void brcmf_fw_add_defaults(struct nvram_parser *nvp)
362{
363	if (nvp->boardrev_found)
364		return;
365
366	memcpy(&nvp->nvram[nvp->nvram_len], &BRCMF_FW_DEFAULT_BOARDREV,
367	       strlen(BRCMF_FW_DEFAULT_BOARDREV));
368	nvp->nvram_len += strlen(BRCMF_FW_DEFAULT_BOARDREV);
369	nvp->nvram[nvp->nvram_len] = '\0';
370	nvp->nvram_len++;
371}
372
373/* brcmf_nvram_strip :Takes a buffer of "<var>=<value>\n" lines read from a fil
374 * and ending in a NUL. Removes carriage returns, empty lines, comment lines,
375 * and converts newlines to NULs. Shortens buffer as needed and pads with NULs.
376 * End of buffer is completed with token identifying length of buffer.
377 */
378static void *brcmf_fw_nvram_strip(const u8 *data, size_t data_len,
379				  u32 *new_length, u16 domain_nr, u16 bus_nr)
380{
381	struct nvram_parser nvp;
382	u32 pad;
383	u32 token;
384	__le32 token_le;
385
386	if (brcmf_init_nvram_parser(&nvp, data, data_len) < 0)
387		return NULL;
388
389	while (nvp.pos < data_len) {
390		nvp.state = nv_parser_states[nvp.state](&nvp);
391		if (nvp.state == END)
392			break;
393	}
394	if (nvp.multi_dev_v1) {
395		nvp.boardrev_found = false;
396		brcmf_fw_strip_multi_v1(&nvp, domain_nr, bus_nr);
397	} else if (nvp.multi_dev_v2) {
398		nvp.boardrev_found = false;
399		brcmf_fw_strip_multi_v2(&nvp, domain_nr, bus_nr);
400	}
401
402	if (nvp.nvram_len == 0) {
403		kfree(nvp.nvram);
404		return NULL;
405	}
406
407	brcmf_fw_add_defaults(&nvp);
408
409	pad = nvp.nvram_len;
410	*new_length = roundup(nvp.nvram_len + 1, 4);
411	while (pad != *new_length) {
412		nvp.nvram[pad] = 0;
413		pad++;
414	}
415
416	token = *new_length / 4;
417	token = (~token << 16) | (token & 0x0000FFFF);
418	token_le = cpu_to_le32(token);
419
420	memcpy(&nvp.nvram[*new_length], &token_le, sizeof(token_le));
421	*new_length += sizeof(token_le);
422
423	return nvp.nvram;
424}
425
426void brcmf_fw_nvram_free(void *nvram)
427{
428	kfree(nvram);
429}
430
431struct brcmf_fw {
432	struct device *dev;
433	struct brcmf_fw_request *req;
434	u32 curpos;
435	void (*done)(struct device *dev, int err, struct brcmf_fw_request *req);
436};
437
438static void brcmf_fw_request_done(const struct firmware *fw, void *ctx);
439
440#ifdef CONFIG_EFI
441/* In some cases the EFI-var stored nvram contains "ccode=ALL" or "ccode=XV"
442 * to specify "worldwide" compatible settings, but these 2 ccode-s do not work
443 * properly. "ccode=ALL" causes channels 12 and 13 to not be available,
444 * "ccode=XV" causes all 5GHz channels to not be available. So we replace both
445 * with "ccode=X2" which allows channels 12+13 and 5Ghz channels in
446 * no-Initiate-Radiation mode. This means that we will never send on these
447 * channels without first having received valid wifi traffic on the channel.
448 */
449static void brcmf_fw_fix_efi_nvram_ccode(char *data, unsigned long data_len)
450{
451	char *ccode;
452
453	ccode = strnstr((char *)data, "ccode=ALL", data_len);
454	if (!ccode)
455		ccode = strnstr((char *)data, "ccode=XV\r", data_len);
456	if (!ccode)
457		return;
458
459	ccode[6] = 'X';
460	ccode[7] = '2';
461	ccode[8] = '\r';
462}
463
464static u8 *brcmf_fw_nvram_from_efi(size_t *data_len_ret)
465{
466	const u16 name[] = { 'n', 'v', 'r', 'a', 'm', 0 };
467	struct efivar_entry *nvram_efivar;
468	unsigned long data_len = 0;
469	u8 *data = NULL;
470	int err;
471
472	nvram_efivar = kzalloc(sizeof(*nvram_efivar), GFP_KERNEL);
473	if (!nvram_efivar)
474		return NULL;
475
476	memcpy(&nvram_efivar->var.VariableName, name, sizeof(name));
477	nvram_efivar->var.VendorGuid = EFI_GUID(0x74b00bd9, 0x805a, 0x4d61,
478						0xb5, 0x1f, 0x43, 0x26,
479						0x81, 0x23, 0xd1, 0x13);
480
481	err = efivar_entry_size(nvram_efivar, &data_len);
482	if (err)
483		goto fail;
484
485	data = kmalloc(data_len, GFP_KERNEL);
486	if (!data)
487		goto fail;
488
489	err = efivar_entry_get(nvram_efivar, NULL, &data_len, data);
490	if (err)
491		goto fail;
492
493	brcmf_fw_fix_efi_nvram_ccode(data, data_len);
494	brcmf_info("Using nvram EFI variable\n");
495
496	kfree(nvram_efivar);
497	*data_len_ret = data_len;
498	return data;
499
500fail:
501	kfree(data);
502	kfree(nvram_efivar);
503	return NULL;
504}
505#else
506static inline u8 *brcmf_fw_nvram_from_efi(size_t *data_len) { return NULL; }
507#endif
508
509static void brcmf_fw_free_request(struct brcmf_fw_request *req)
510{
511	struct brcmf_fw_item *item;
512	int i;
513
514	for (i = 0, item = &req->items[0]; i < req->n_items; i++, item++) {
515		if (item->type == BRCMF_FW_TYPE_BINARY)
516			release_firmware(item->binary);
517		else if (item->type == BRCMF_FW_TYPE_NVRAM)
518			brcmf_fw_nvram_free(item->nv_data.data);
519	}
520	kfree(req);
521}
522
523static int brcmf_fw_request_nvram_done(const struct firmware *fw, void *ctx)
524{
525	struct brcmf_fw *fwctx = ctx;
526	struct brcmf_fw_item *cur;
527	bool free_bcm47xx_nvram = false;
528	bool kfree_nvram = false;
529	u32 nvram_length = 0;
530	void *nvram = NULL;
531	u8 *data = NULL;
532	size_t data_len;
533
534	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(fwctx->dev));
535
536	cur = &fwctx->req->items[fwctx->curpos];
537
538	if (fw && fw->data) {
539		data = (u8 *)fw->data;
540		data_len = fw->size;
541	} else {
542		if ((data = bcm47xx_nvram_get_contents(&data_len)))
543			free_bcm47xx_nvram = true;
544		else if ((data = brcmf_fw_nvram_from_efi(&data_len)))
545			kfree_nvram = true;
546		else if (!(cur->flags & BRCMF_FW_REQF_OPTIONAL))
547			goto fail;
548	}
549
550	if (data)
551		nvram = brcmf_fw_nvram_strip(data, data_len, &nvram_length,
552					     fwctx->req->domain_nr,
553					     fwctx->req->bus_nr);
554
555	if (free_bcm47xx_nvram)
556		bcm47xx_nvram_release_contents(data);
557	if (kfree_nvram)
558		kfree(data);
559
560	release_firmware(fw);
561	if (!nvram && !(cur->flags & BRCMF_FW_REQF_OPTIONAL))
562		goto fail;
563
564	brcmf_dbg(TRACE, "nvram %p len %d\n", nvram, nvram_length);
565	cur->nv_data.data = nvram;
566	cur->nv_data.len = nvram_length;
567	return 0;
568
569fail:
570	return -ENOENT;
571}
572
573static int brcmf_fw_complete_request(const struct firmware *fw,
574				     struct brcmf_fw *fwctx)
575{
576	struct brcmf_fw_item *cur = &fwctx->req->items[fwctx->curpos];
577	int ret = 0;
578
579	brcmf_dbg(TRACE, "firmware %s %sfound\n", cur->path, fw ? "" : "not ");
580
581	switch (cur->type) {
582	case BRCMF_FW_TYPE_NVRAM:
583		ret = brcmf_fw_request_nvram_done(fw, fwctx);
584		break;
585	case BRCMF_FW_TYPE_BINARY:
586		if (fw)
587			cur->binary = fw;
588		else
589			ret = -ENOENT;
590		break;
591	default:
592		/* something fishy here so bail out early */
593		brcmf_err("unknown fw type: %d\n", cur->type);
594		release_firmware(fw);
595		ret = -EINVAL;
596	}
597
598	return (cur->flags & BRCMF_FW_REQF_OPTIONAL) ? 0 : ret;
599}
600
601static int brcmf_fw_request_firmware(const struct firmware **fw,
602				     struct brcmf_fw *fwctx)
603{
604	struct brcmf_fw_item *cur = &fwctx->req->items[fwctx->curpos];
605	int ret;
606
607	/* nvram files are board-specific, first try a board-specific path */
608	if (cur->type == BRCMF_FW_TYPE_NVRAM && fwctx->req->board_type) {
609		char alt_path[BRCMF_FW_NAME_LEN];
610
611		strlcpy(alt_path, cur->path, BRCMF_FW_NAME_LEN);
612		/* strip .txt at the end */
613		alt_path[strlen(alt_path) - 4] = 0;
614		strlcat(alt_path, ".", BRCMF_FW_NAME_LEN);
615		strlcat(alt_path, fwctx->req->board_type, BRCMF_FW_NAME_LEN);
616		strlcat(alt_path, ".txt", BRCMF_FW_NAME_LEN);
617
618		ret = request_firmware(fw, alt_path, fwctx->dev);
619		if (ret == 0)
620			return ret;
621	}
622
623	return request_firmware(fw, cur->path, fwctx->dev);
624}
625
626static void brcmf_fw_request_done(const struct firmware *fw, void *ctx)
627{
628	struct brcmf_fw *fwctx = ctx;
629	int ret;
630
631	ret = brcmf_fw_complete_request(fw, fwctx);
632
633	while (ret == 0 && ++fwctx->curpos < fwctx->req->n_items) {
634		brcmf_fw_request_firmware(&fw, fwctx);
635		ret = brcmf_fw_complete_request(fw, ctx);
636	}
637
638	if (ret) {
639		brcmf_fw_free_request(fwctx->req);
640		fwctx->req = NULL;
641	}
642	fwctx->done(fwctx->dev, ret, fwctx->req);
643	kfree(fwctx);
644}
645
646static bool brcmf_fw_request_is_valid(struct brcmf_fw_request *req)
647{
648	struct brcmf_fw_item *item;
649	int i;
650
651	if (!req->n_items)
652		return false;
653
654	for (i = 0, item = &req->items[0]; i < req->n_items; i++, item++) {
655		if (!item->path)
656			return false;
657	}
658	return true;
659}
660
661int brcmf_fw_get_firmwares(struct device *dev, struct brcmf_fw_request *req,
662			   void (*fw_cb)(struct device *dev, int err,
663					 struct brcmf_fw_request *req))
664{
665	struct brcmf_fw_item *first = &req->items[0];
666	struct brcmf_fw *fwctx;
667	int ret;
668
669	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(dev));
670	if (!fw_cb)
671		return -EINVAL;
672
673	if (!brcmf_fw_request_is_valid(req))
674		return -EINVAL;
675
676	fwctx = kzalloc(sizeof(*fwctx), GFP_KERNEL);
677	if (!fwctx)
678		return -ENOMEM;
679
680	fwctx->dev = dev;
681	fwctx->req = req;
682	fwctx->done = fw_cb;
683
684	ret = request_firmware_nowait(THIS_MODULE, true, first->path,
685				      fwctx->dev, GFP_KERNEL, fwctx,
686				      brcmf_fw_request_done);
687	if (ret < 0)
688		brcmf_fw_request_done(NULL, fwctx);
689
690	return 0;
691}
692
693struct brcmf_fw_request *
694brcmf_fw_alloc_request(u32 chip, u32 chiprev,
695		       const struct brcmf_firmware_mapping mapping_table[],
696		       u32 table_size, struct brcmf_fw_name *fwnames,
697		       u32 n_fwnames)
698{
699	struct brcmf_fw_request *fwreq;
700	char chipname[12];
701	const char *mp_path;
702	size_t mp_path_len;
703	u32 i, j;
704	char end = '\0';
705
706	if (chiprev >= BITS_PER_TYPE(u32)) {
707		brcmf_err("Invalid chip revision %u\n", chiprev);
708		return NULL;
709	}
710
711	for (i = 0; i < table_size; i++) {
712		if (mapping_table[i].chipid == chip &&
713		    mapping_table[i].revmask & BIT(chiprev))
714			break;
715	}
716
717	brcmf_chip_name(chip, chiprev, chipname, sizeof(chipname));
718
719	if (i == table_size) {
720		brcmf_err("Unknown chip %s\n", chipname);
721		return NULL;
722	}
723
724	fwreq = kzalloc(struct_size(fwreq, items, n_fwnames), GFP_KERNEL);
725	if (!fwreq)
726		return NULL;
727
728	brcmf_info("using %s for chip %s\n",
729		   mapping_table[i].fw_base, chipname);
730
731	mp_path = brcmf_mp_global.firmware_path;
732	mp_path_len = strnlen(mp_path, BRCMF_FW_ALTPATH_LEN);
733	if (mp_path_len)
734		end = mp_path[mp_path_len - 1];
735
736	fwreq->n_items = n_fwnames;
737
738	for (j = 0; j < n_fwnames; j++) {
739		fwreq->items[j].path = fwnames[j].path;
740		fwnames[j].path[0] = '\0';
741		/* check if firmware path is provided by module parameter */
742		if (brcmf_mp_global.firmware_path[0] != '\0') {
743			strlcpy(fwnames[j].path, mp_path,
744				BRCMF_FW_NAME_LEN);
745
746			if (end != '/') {
747				strlcat(fwnames[j].path, "/",
748					BRCMF_FW_NAME_LEN);
749			}
750		}
751		strlcat(fwnames[j].path, mapping_table[i].fw_base,
752			BRCMF_FW_NAME_LEN);
753		strlcat(fwnames[j].path, fwnames[j].extension,
754			BRCMF_FW_NAME_LEN);
755		fwreq->items[j].path = fwnames[j].path;
756	}
757
758	return fwreq;
759}
760