[go: nahoru, domu]
1/*
2 * Copyright (c) 2013 Broadcom Corporation
3 *
4 * Permission to use, copy, modify, and/or distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
11 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
13 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
14 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16
17#include <linux/kernel.h>
18#include <linux/slab.h>
19#include <linux/device.h>
20#include <linux/firmware.h>
21#include <linux/module.h>
22
23#include "dhd_dbg.h"
24#include "firmware.h"
25
26char brcmf_firmware_path[BRCMF_FW_PATH_LEN];
27module_param_string(firmware_path, brcmf_firmware_path,
28		    BRCMF_FW_PATH_LEN, 0440);
29
30enum nvram_parser_state {
31	IDLE,
32	KEY,
33	VALUE,
34	COMMENT,
35	END
36};
37
38/**
39 * struct nvram_parser - internal info for parser.
40 *
41 * @state: current parser state.
42 * @fwnv: input buffer being parsed.
43 * @nvram: output buffer with parse result.
44 * @nvram_len: lenght of parse result.
45 * @line: current line.
46 * @column: current column in line.
47 * @pos: byte offset in input buffer.
48 * @entry: start position of key,value entry.
49 */
50struct nvram_parser {
51	enum nvram_parser_state state;
52	const struct firmware *fwnv;
53	u8 *nvram;
54	u32 nvram_len;
55	u32 line;
56	u32 column;
57	u32 pos;
58	u32 entry;
59};
60
61static bool is_nvram_char(char c)
62{
63	/* comment marker excluded */
64	if (c == '#')
65		return false;
66
67	/* key and value may have any other readable character */
68	return (c > 0x20 && c < 0x7f);
69}
70
71static bool is_whitespace(char c)
72{
73	return (c == ' ' || c == '\r' || c == '\n' || c == '\t');
74}
75
76static enum nvram_parser_state brcmf_nvram_handle_idle(struct nvram_parser *nvp)
77{
78	char c;
79
80	c = nvp->fwnv->data[nvp->pos];
81	if (c == '\n')
82		return COMMENT;
83	if (is_whitespace(c))
84		goto proceed;
85	if (c == '#')
86		return COMMENT;
87	if (is_nvram_char(c)) {
88		nvp->entry = nvp->pos;
89		return KEY;
90	}
91	brcmf_dbg(INFO, "warning: ln=%d:col=%d: ignoring invalid character\n",
92		  nvp->line, nvp->column);
93proceed:
94	nvp->column++;
95	nvp->pos++;
96	return IDLE;
97}
98
99static enum nvram_parser_state brcmf_nvram_handle_key(struct nvram_parser *nvp)
100{
101	enum nvram_parser_state st = nvp->state;
102	char c;
103
104	c = nvp->fwnv->data[nvp->pos];
105	if (c == '=') {
106		st = VALUE;
107	} else if (!is_nvram_char(c)) {
108		brcmf_dbg(INFO, "warning: ln=%d:col=%d: '=' expected, skip invalid key entry\n",
109			  nvp->line, nvp->column);
110		return COMMENT;
111	}
112
113	nvp->column++;
114	nvp->pos++;
115	return st;
116}
117
118static enum nvram_parser_state
119brcmf_nvram_handle_value(struct nvram_parser *nvp)
120{
121	char c;
122	char *skv;
123	char *ekv;
124	u32 cplen;
125
126	c = nvp->fwnv->data[nvp->pos];
127	if (!is_nvram_char(c)) {
128		/* key,value pair complete */
129		ekv = (u8 *)&nvp->fwnv->data[nvp->pos];
130		skv = (u8 *)&nvp->fwnv->data[nvp->entry];
131		cplen = ekv - skv;
132		/* copy to output buffer */
133		memcpy(&nvp->nvram[nvp->nvram_len], skv, cplen);
134		nvp->nvram_len += cplen;
135		nvp->nvram[nvp->nvram_len] = '\0';
136		nvp->nvram_len++;
137		return IDLE;
138	}
139	nvp->pos++;
140	nvp->column++;
141	return VALUE;
142}
143
144static enum nvram_parser_state
145brcmf_nvram_handle_comment(struct nvram_parser *nvp)
146{
147	char *eol, *sol;
148
149	sol = (char *)&nvp->fwnv->data[nvp->pos];
150	eol = strchr(sol, '\n');
151	if (eol == NULL)
152		return END;
153
154	/* eat all moving to next line */
155	nvp->line++;
156	nvp->column = 1;
157	nvp->pos += (eol - sol) + 1;
158	return IDLE;
159}
160
161static enum nvram_parser_state brcmf_nvram_handle_end(struct nvram_parser *nvp)
162{
163	/* final state */
164	return END;
165}
166
167static enum nvram_parser_state
168(*nv_parser_states[])(struct nvram_parser *nvp) = {
169	brcmf_nvram_handle_idle,
170	brcmf_nvram_handle_key,
171	brcmf_nvram_handle_value,
172	brcmf_nvram_handle_comment,
173	brcmf_nvram_handle_end
174};
175
176static int brcmf_init_nvram_parser(struct nvram_parser *nvp,
177				   const struct firmware *nv)
178{
179	memset(nvp, 0, sizeof(*nvp));
180	nvp->fwnv = nv;
181	/* Alloc for extra 0 byte + roundup by 4 + length field */
182	nvp->nvram = kzalloc(nv->size + 1 + 3 + sizeof(u32), GFP_KERNEL);
183	if (!nvp->nvram)
184		return -ENOMEM;
185
186	nvp->line = 1;
187	nvp->column = 1;
188	return 0;
189}
190
191/* brcmf_nvram_strip :Takes a buffer of "<var>=<value>\n" lines read from a fil
192 * and ending in a NUL. Removes carriage returns, empty lines, comment lines,
193 * and converts newlines to NULs. Shortens buffer as needed and pads with NULs.
194 * End of buffer is completed with token identifying length of buffer.
195 */
196static void *brcmf_fw_nvram_strip(const struct firmware *nv, u32 *new_length)
197{
198	struct nvram_parser nvp;
199	u32 pad;
200	u32 token;
201	__le32 token_le;
202
203	if (brcmf_init_nvram_parser(&nvp, nv) < 0)
204		return NULL;
205
206	while (nvp.pos < nv->size) {
207		nvp.state = nv_parser_states[nvp.state](&nvp);
208		if (nvp.state == END)
209			break;
210	}
211	pad = nvp.nvram_len;
212	*new_length = roundup(nvp.nvram_len + 1, 4);
213	while (pad != *new_length) {
214		nvp.nvram[pad] = 0;
215		pad++;
216	}
217
218	token = *new_length / 4;
219	token = (~token << 16) | (token & 0x0000FFFF);
220	token_le = cpu_to_le32(token);
221
222	memcpy(&nvp.nvram[*new_length], &token_le, sizeof(token_le));
223	*new_length += sizeof(token_le);
224
225	return nvp.nvram;
226}
227
228void brcmf_fw_nvram_free(void *nvram)
229{
230	kfree(nvram);
231}
232
233struct brcmf_fw {
234	struct device *dev;
235	u16 flags;
236	const struct firmware *code;
237	const char *nvram_name;
238	void (*done)(struct device *dev, const struct firmware *fw,
239		     void *nvram_image, u32 nvram_len);
240};
241
242static void brcmf_fw_request_nvram_done(const struct firmware *fw, void *ctx)
243{
244	struct brcmf_fw *fwctx = ctx;
245	u32 nvram_length = 0;
246	void *nvram = NULL;
247
248	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(fwctx->dev));
249	if (!fw && !(fwctx->flags & BRCMF_FW_REQ_NV_OPTIONAL))
250		goto fail;
251
252	if (fw) {
253		nvram = brcmf_fw_nvram_strip(fw, &nvram_length);
254		release_firmware(fw);
255		if (!nvram && !(fwctx->flags & BRCMF_FW_REQ_NV_OPTIONAL))
256			goto fail;
257	}
258
259	fwctx->done(fwctx->dev, fwctx->code, nvram, nvram_length);
260	kfree(fwctx);
261	return;
262
263fail:
264	brcmf_dbg(TRACE, "failed: dev=%s\n", dev_name(fwctx->dev));
265	if (fwctx->code)
266		release_firmware(fwctx->code);
267	device_release_driver(fwctx->dev);
268	kfree(fwctx);
269}
270
271static void brcmf_fw_request_code_done(const struct firmware *fw, void *ctx)
272{
273	struct brcmf_fw *fwctx = ctx;
274	int ret;
275
276	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(fwctx->dev));
277	if (!fw)
278		goto fail;
279
280	/* only requested code so done here */
281	if (!(fwctx->flags & BRCMF_FW_REQUEST_NVRAM)) {
282		fwctx->done(fwctx->dev, fw, NULL, 0);
283		kfree(fwctx);
284		return;
285	}
286	fwctx->code = fw;
287	ret = request_firmware_nowait(THIS_MODULE, true, fwctx->nvram_name,
288				      fwctx->dev, GFP_KERNEL, fwctx,
289				      brcmf_fw_request_nvram_done);
290
291	if (!ret)
292		return;
293
294	/* when nvram is optional call .done() callback here */
295	if (fwctx->flags & BRCMF_FW_REQ_NV_OPTIONAL) {
296		fwctx->done(fwctx->dev, fw, NULL, 0);
297		kfree(fwctx);
298		return;
299	}
300
301	/* failed nvram request */
302	release_firmware(fw);
303fail:
304	brcmf_dbg(TRACE, "failed: dev=%s\n", dev_name(fwctx->dev));
305	device_release_driver(fwctx->dev);
306	kfree(fwctx);
307}
308
309int brcmf_fw_get_firmwares(struct device *dev, u16 flags,
310			   const char *code, const char *nvram,
311			   void (*fw_cb)(struct device *dev,
312					 const struct firmware *fw,
313					 void *nvram_image, u32 nvram_len))
314{
315	struct brcmf_fw *fwctx;
316
317	brcmf_dbg(TRACE, "enter: dev=%s\n", dev_name(dev));
318	if (!fw_cb || !code)
319		return -EINVAL;
320
321	if ((flags & BRCMF_FW_REQUEST_NVRAM) && !nvram)
322		return -EINVAL;
323
324	fwctx = kzalloc(sizeof(*fwctx), GFP_KERNEL);
325	if (!fwctx)
326		return -ENOMEM;
327
328	fwctx->dev = dev;
329	fwctx->flags = flags;
330	fwctx->done = fw_cb;
331	if (flags & BRCMF_FW_REQUEST_NVRAM)
332		fwctx->nvram_name = nvram;
333
334	return request_firmware_nowait(THIS_MODULE, true, code, dev,
335				       GFP_KERNEL, fwctx,
336				       brcmf_fw_request_code_done);
337}
338