• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 
26 char brcmf_firmware_path[BRCMF_FW_PATH_LEN];
27 module_param_string(firmware_path, brcmf_firmware_path,
28 		    BRCMF_FW_PATH_LEN, 0440);
29 
30 enum 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  */
50 struct 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 
is_nvram_char(char c)61 static 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 
is_whitespace(char c)71 static bool is_whitespace(char c)
72 {
73 	return (c == ' ' || c == '\r' || c == '\n' || c == '\t');
74 }
75 
brcmf_nvram_handle_idle(struct nvram_parser * nvp)76 static 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);
93 proceed:
94 	nvp->column++;
95 	nvp->pos++;
96 	return IDLE;
97 }
98 
brcmf_nvram_handle_key(struct nvram_parser * nvp)99 static 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 
118 static enum nvram_parser_state
brcmf_nvram_handle_value(struct nvram_parser * nvp)119 brcmf_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 
144 static enum nvram_parser_state
brcmf_nvram_handle_comment(struct nvram_parser * nvp)145 brcmf_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 
brcmf_nvram_handle_end(struct nvram_parser * nvp)161 static enum nvram_parser_state brcmf_nvram_handle_end(struct nvram_parser *nvp)
162 {
163 	/* final state */
164 	return END;
165 }
166 
167 static 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 
brcmf_init_nvram_parser(struct nvram_parser * nvp,const struct firmware * nv)176 static 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  */
brcmf_fw_nvram_strip(const struct firmware * nv,u32 * new_length)196 static 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 
brcmf_fw_nvram_free(void * nvram)228 void brcmf_fw_nvram_free(void *nvram)
229 {
230 	kfree(nvram);
231 }
232 
233 struct 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 
brcmf_fw_request_nvram_done(const struct firmware * fw,void * ctx)242 static 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 
263 fail:
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 
brcmf_fw_request_code_done(const struct firmware * fw,void * ctx)271 static 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);
303 fail:
304 	brcmf_dbg(TRACE, "failed: dev=%s\n", dev_name(fwctx->dev));
305 	device_release_driver(fwctx->dev);
306 	kfree(fwctx);
307 }
308 
brcmf_fw_get_firmwares(struct device * dev,u16 flags,const char * code,const char * nvram,void (* fw_cb)(struct device * dev,const struct firmware * fw,void * nvram_image,u32 nvram_len))309 int 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