1 /*
2  * Copyright (c) 2010 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 /*******************************************************************************
18  * Communicates with the dongle by using dcmd codes.
19  * For certain dcmd codes, the dongle interprets string data from the host.
20  ******************************************************************************/
21 
22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23 
24 #include <linux/types.h>
25 #include <linux/netdevice.h>
26 #include <linux/sched.h>
27 #include <defs.h>
28 
29 #include <brcmu_utils.h>
30 #include <brcmu_wifi.h>
31 
32 #include "dhd.h"
33 #include "dhd_proto.h"
34 #include "dhd_bus.h"
35 #include "dhd_dbg.h"
36 
37 struct brcmf_proto_cdc_dcmd {
38 	__le32 cmd;	/* dongle command value */
39 	__le32 len;	/* lower 16: output buflen;
40 			 * upper 16: input buflen (excludes header) */
41 	__le32 flags;	/* flag defns given below */
42 	__le32 status;	/* status code returned from the device */
43 };
44 
45 /* Max valid buffer size that can be sent to the dongle */
46 #define CDC_MAX_MSG_SIZE	(ETH_FRAME_LEN+ETH_FCS_LEN)
47 
48 /* CDC flag definitions */
49 #define CDC_DCMD_ERROR		0x01	/* 1=cmd failed */
50 #define CDC_DCMD_SET		0x02	/* 0=get, 1=set cmd */
51 #define CDC_DCMD_IF_MASK	0xF000		/* I/F index */
52 #define CDC_DCMD_IF_SHIFT	12
53 #define CDC_DCMD_ID_MASK	0xFFFF0000	/* id an cmd pairing */
54 #define CDC_DCMD_ID_SHIFT	16		/* ID Mask shift bits */
55 #define CDC_DCMD_ID(flags)	\
56 	(((flags) & CDC_DCMD_ID_MASK) >> CDC_DCMD_ID_SHIFT)
57 
58 /*
59  * BDC header - Broadcom specific extension of CDC.
60  * Used on data packets to convey priority across USB.
61  */
62 #define	BDC_HEADER_LEN		4
63 #define BDC_PROTO_VER		2	/* Protocol version */
64 #define BDC_FLAG_VER_MASK	0xf0	/* Protocol version mask */
65 #define BDC_FLAG_VER_SHIFT	4	/* Protocol version shift */
66 #define BDC_FLAG_SUM_GOOD	0x04	/* Good RX checksums */
67 #define BDC_FLAG_SUM_NEEDED	0x08	/* Dongle needs to do TX checksums */
68 #define BDC_PRIORITY_MASK	0x7
69 #define BDC_FLAG2_IF_MASK	0x0f	/* packet rx interface in APSTA */
70 #define BDC_FLAG2_IF_SHIFT	0
71 
72 #define BDC_GET_IF_IDX(hdr) \
73 	((int)((((hdr)->flags2) & BDC_FLAG2_IF_MASK) >> BDC_FLAG2_IF_SHIFT))
74 #define BDC_SET_IF_IDX(hdr, idx) \
75 	((hdr)->flags2 = (((hdr)->flags2 & ~BDC_FLAG2_IF_MASK) | \
76 	((idx) << BDC_FLAG2_IF_SHIFT)))
77 
78 struct brcmf_proto_bdc_header {
79 	u8 flags;
80 	u8 priority;	/* 802.1d Priority, 4:7 flow control info for usb */
81 	u8 flags2;
82 	u8 data_offset;
83 };
84 
85 
86 #define RETRIES 2 /* # of retries to retrieve matching dcmd response */
87 #define BUS_HEADER_LEN	(16+64)		/* Must be atleast SDPCM_RESERVE
88 					 * (amount of header tha might be added)
89 					 * plus any space that might be needed
90 					 * for bus alignment padding.
91 					 */
92 #define ROUND_UP_MARGIN	2048	/* Biggest bus block size possible for
93 				 * round off at the end of buffer
94 				 * Currently is SDIO
95 				 */
96 
97 struct brcmf_proto {
98 	u16 reqid;
99 	u8 pending;
100 	u32 lastcmd;
101 	u8 bus_header[BUS_HEADER_LEN];
102 	struct brcmf_proto_cdc_dcmd msg;
103 	unsigned char buf[BRCMF_DCMD_MAXLEN + ROUND_UP_MARGIN];
104 };
105 
brcmf_proto_cdc_msg(struct brcmf_pub * drvr)106 static int brcmf_proto_cdc_msg(struct brcmf_pub *drvr)
107 {
108 	struct brcmf_proto *prot = drvr->prot;
109 	int len = le32_to_cpu(prot->msg.len) +
110 			sizeof(struct brcmf_proto_cdc_dcmd);
111 
112 	brcmf_dbg(TRACE, "Enter\n");
113 
114 	/* NOTE : cdc->msg.len holds the desired length of the buffer to be
115 	 *        returned. Only up to CDC_MAX_MSG_SIZE of this buffer area
116 	 *        is actually sent to the dongle
117 	 */
118 	if (len > CDC_MAX_MSG_SIZE)
119 		len = CDC_MAX_MSG_SIZE;
120 
121 	/* Send request */
122 	return drvr->bus_if->brcmf_bus_txctl(drvr->dev,
123 					     (unsigned char *)&prot->msg,
124 					     len);
125 }
126 
brcmf_proto_cdc_cmplt(struct brcmf_pub * drvr,u32 id,u32 len)127 static int brcmf_proto_cdc_cmplt(struct brcmf_pub *drvr, u32 id, u32 len)
128 {
129 	int ret;
130 	struct brcmf_proto *prot = drvr->prot;
131 
132 	brcmf_dbg(TRACE, "Enter\n");
133 
134 	do {
135 		ret = drvr->bus_if->brcmf_bus_rxctl(drvr->dev,
136 				(unsigned char *)&prot->msg,
137 				len + sizeof(struct brcmf_proto_cdc_dcmd));
138 		if (ret < 0)
139 			break;
140 	} while (CDC_DCMD_ID(le32_to_cpu(prot->msg.flags)) != id);
141 
142 	return ret;
143 }
144 
145 int
brcmf_proto_cdc_query_dcmd(struct brcmf_pub * drvr,int ifidx,uint cmd,void * buf,uint len)146 brcmf_proto_cdc_query_dcmd(struct brcmf_pub *drvr, int ifidx, uint cmd,
147 			       void *buf, uint len)
148 {
149 	struct brcmf_proto *prot = drvr->prot;
150 	struct brcmf_proto_cdc_dcmd *msg = &prot->msg;
151 	void *info;
152 	int ret = 0, retries = 0;
153 	u32 id, flags;
154 
155 	brcmf_dbg(TRACE, "Enter\n");
156 	brcmf_dbg(CTL, "cmd %d len %d\n", cmd, len);
157 
158 	/* Respond "bcmerror" and "bcmerrorstr" with local cache */
159 	if (cmd == BRCMF_C_GET_VAR && buf) {
160 		if (!strcmp((char *)buf, "bcmerrorstr")) {
161 			strncpy((char *)buf, "bcm_error",
162 				BCME_STRLEN);
163 			goto done;
164 		} else if (!strcmp((char *)buf, "bcmerror")) {
165 			*(int *)buf = drvr->dongle_error;
166 			goto done;
167 		}
168 	}
169 
170 	memset(msg, 0, sizeof(struct brcmf_proto_cdc_dcmd));
171 
172 	msg->cmd = cpu_to_le32(cmd);
173 	msg->len = cpu_to_le32(len);
174 	flags = (++prot->reqid << CDC_DCMD_ID_SHIFT);
175 	flags = (flags & ~CDC_DCMD_IF_MASK) |
176 		(ifidx << CDC_DCMD_IF_SHIFT);
177 	msg->flags = cpu_to_le32(flags);
178 
179 	if (buf)
180 		memcpy(prot->buf, buf, len);
181 
182 	ret = brcmf_proto_cdc_msg(drvr);
183 	if (ret < 0) {
184 		brcmf_dbg(ERROR, "brcmf_proto_cdc_msg failed w/status %d\n",
185 			  ret);
186 		goto done;
187 	}
188 
189 retry:
190 	/* wait for interrupt and get first fragment */
191 	ret = brcmf_proto_cdc_cmplt(drvr, prot->reqid, len);
192 	if (ret < 0)
193 		goto done;
194 
195 	flags = le32_to_cpu(msg->flags);
196 	id = (flags & CDC_DCMD_ID_MASK) >> CDC_DCMD_ID_SHIFT;
197 
198 	if ((id < prot->reqid) && (++retries < RETRIES))
199 		goto retry;
200 	if (id != prot->reqid) {
201 		brcmf_dbg(ERROR, "%s: unexpected request id %d (expected %d)\n",
202 			  brcmf_ifname(drvr, ifidx), id, prot->reqid);
203 		ret = -EINVAL;
204 		goto done;
205 	}
206 
207 	/* Check info buffer */
208 	info = (void *)&msg[1];
209 
210 	/* Copy info buffer */
211 	if (buf) {
212 		if (ret < (int)len)
213 			len = ret;
214 		memcpy(buf, info, len);
215 	}
216 
217 	/* Check the ERROR flag */
218 	if (flags & CDC_DCMD_ERROR) {
219 		ret = le32_to_cpu(msg->status);
220 		/* Cache error from dongle */
221 		drvr->dongle_error = ret;
222 	}
223 
224 done:
225 	return ret;
226 }
227 
brcmf_proto_cdc_set_dcmd(struct brcmf_pub * drvr,int ifidx,uint cmd,void * buf,uint len)228 int brcmf_proto_cdc_set_dcmd(struct brcmf_pub *drvr, int ifidx, uint cmd,
229 				 void *buf, uint len)
230 {
231 	struct brcmf_proto *prot = drvr->prot;
232 	struct brcmf_proto_cdc_dcmd *msg = &prot->msg;
233 	int ret = 0;
234 	u32 flags, id;
235 
236 	brcmf_dbg(TRACE, "Enter\n");
237 	brcmf_dbg(CTL, "cmd %d len %d\n", cmd, len);
238 
239 	memset(msg, 0, sizeof(struct brcmf_proto_cdc_dcmd));
240 
241 	msg->cmd = cpu_to_le32(cmd);
242 	msg->len = cpu_to_le32(len);
243 	flags = (++prot->reqid << CDC_DCMD_ID_SHIFT) | CDC_DCMD_SET;
244 	flags = (flags & ~CDC_DCMD_IF_MASK) |
245 		(ifidx << CDC_DCMD_IF_SHIFT);
246 	msg->flags = cpu_to_le32(flags);
247 
248 	if (buf)
249 		memcpy(prot->buf, buf, len);
250 
251 	ret = brcmf_proto_cdc_msg(drvr);
252 	if (ret < 0)
253 		goto done;
254 
255 	ret = brcmf_proto_cdc_cmplt(drvr, prot->reqid, len);
256 	if (ret < 0)
257 		goto done;
258 
259 	flags = le32_to_cpu(msg->flags);
260 	id = (flags & CDC_DCMD_ID_MASK) >> CDC_DCMD_ID_SHIFT;
261 
262 	if (id != prot->reqid) {
263 		brcmf_dbg(ERROR, "%s: unexpected request id %d (expected %d)\n",
264 			  brcmf_ifname(drvr, ifidx), id, prot->reqid);
265 		ret = -EINVAL;
266 		goto done;
267 	}
268 
269 	/* Check the ERROR flag */
270 	if (flags & CDC_DCMD_ERROR) {
271 		ret = le32_to_cpu(msg->status);
272 		/* Cache error from dongle */
273 		drvr->dongle_error = ret;
274 	}
275 
276 done:
277 	return ret;
278 }
279 
280 int
brcmf_proto_dcmd(struct brcmf_pub * drvr,int ifidx,struct brcmf_dcmd * dcmd,int len)281 brcmf_proto_dcmd(struct brcmf_pub *drvr, int ifidx, struct brcmf_dcmd *dcmd,
282 		  int len)
283 {
284 	struct brcmf_proto *prot = drvr->prot;
285 	int ret = -1;
286 
287 	if (drvr->bus_if->state == BRCMF_BUS_DOWN) {
288 		brcmf_dbg(ERROR, "bus is down. we have nothing to do.\n");
289 		return ret;
290 	}
291 	mutex_lock(&drvr->proto_block);
292 
293 	brcmf_dbg(TRACE, "Enter\n");
294 
295 	if (len > BRCMF_DCMD_MAXLEN)
296 		goto done;
297 
298 	if (prot->pending == true) {
299 		brcmf_dbg(TRACE, "CDC packet is pending!!!! cmd=0x%x (%lu) lastcmd=0x%x (%lu)\n",
300 			  dcmd->cmd, (unsigned long)dcmd->cmd, prot->lastcmd,
301 			  (unsigned long)prot->lastcmd);
302 		if (dcmd->cmd == BRCMF_C_SET_VAR ||
303 		    dcmd->cmd == BRCMF_C_GET_VAR)
304 			brcmf_dbg(TRACE, "iovar cmd=%s\n", (char *)dcmd->buf);
305 
306 		goto done;
307 	}
308 
309 	prot->pending = true;
310 	prot->lastcmd = dcmd->cmd;
311 	if (dcmd->set)
312 		ret = brcmf_proto_cdc_set_dcmd(drvr, ifidx, dcmd->cmd,
313 						   dcmd->buf, len);
314 	else {
315 		ret = brcmf_proto_cdc_query_dcmd(drvr, ifidx, dcmd->cmd,
316 						     dcmd->buf, len);
317 		if (ret > 0)
318 			dcmd->used = ret -
319 					sizeof(struct brcmf_proto_cdc_dcmd);
320 	}
321 
322 	if (ret >= 0)
323 		ret = 0;
324 	else {
325 		struct brcmf_proto_cdc_dcmd *msg = &prot->msg;
326 		/* len == needed when set/query fails from dongle */
327 		dcmd->needed = le32_to_cpu(msg->len);
328 	}
329 
330 	/* Intercept the wme_dp dongle cmd here */
331 	if (!ret && dcmd->cmd == BRCMF_C_SET_VAR &&
332 	    !strcmp(dcmd->buf, "wme_dp")) {
333 		int slen;
334 		__le32 val = 0;
335 
336 		slen = strlen("wme_dp") + 1;
337 		if (len >= (int)(slen + sizeof(int)))
338 			memcpy(&val, (char *)dcmd->buf + slen, sizeof(int));
339 		drvr->wme_dp = (u8) le32_to_cpu(val);
340 	}
341 
342 	prot->pending = false;
343 
344 done:
345 	mutex_unlock(&drvr->proto_block);
346 
347 	return ret;
348 }
349 
pkt_sum_needed(struct sk_buff * skb)350 static bool pkt_sum_needed(struct sk_buff *skb)
351 {
352 	return skb->ip_summed == CHECKSUM_PARTIAL;
353 }
354 
pkt_set_sum_good(struct sk_buff * skb,bool x)355 static void pkt_set_sum_good(struct sk_buff *skb, bool x)
356 {
357 	skb->ip_summed = (x ? CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
358 }
359 
brcmf_proto_hdrpush(struct brcmf_pub * drvr,int ifidx,struct sk_buff * pktbuf)360 void brcmf_proto_hdrpush(struct brcmf_pub *drvr, int ifidx,
361 			 struct sk_buff *pktbuf)
362 {
363 	struct brcmf_proto_bdc_header *h;
364 
365 	brcmf_dbg(TRACE, "Enter\n");
366 
367 	/* Push BDC header used to convey priority for buses that don't */
368 
369 	skb_push(pktbuf, BDC_HEADER_LEN);
370 
371 	h = (struct brcmf_proto_bdc_header *)(pktbuf->data);
372 
373 	h->flags = (BDC_PROTO_VER << BDC_FLAG_VER_SHIFT);
374 	if (pkt_sum_needed(pktbuf))
375 		h->flags |= BDC_FLAG_SUM_NEEDED;
376 
377 	h->priority = (pktbuf->priority & BDC_PRIORITY_MASK);
378 	h->flags2 = 0;
379 	h->data_offset = 0;
380 	BDC_SET_IF_IDX(h, ifidx);
381 }
382 
brcmf_proto_hdrpull(struct device * dev,int * ifidx,struct sk_buff * pktbuf)383 int brcmf_proto_hdrpull(struct device *dev, int *ifidx,
384 			struct sk_buff *pktbuf)
385 {
386 	struct brcmf_proto_bdc_header *h;
387 	struct brcmf_bus *bus_if = dev_get_drvdata(dev);
388 	struct brcmf_pub *drvr = bus_if->drvr;
389 
390 	brcmf_dbg(TRACE, "Enter\n");
391 
392 	/* Pop BDC header used to convey priority for buses that don't */
393 
394 	if (pktbuf->len < BDC_HEADER_LEN) {
395 		brcmf_dbg(ERROR, "rx data too short (%d < %d)\n",
396 			  pktbuf->len, BDC_HEADER_LEN);
397 		return -EBADE;
398 	}
399 
400 	h = (struct brcmf_proto_bdc_header *)(pktbuf->data);
401 
402 	*ifidx = BDC_GET_IF_IDX(h);
403 	if (*ifidx >= BRCMF_MAX_IFS) {
404 		brcmf_dbg(ERROR, "rx data ifnum out of range (%d)\n", *ifidx);
405 		return -EBADE;
406 	}
407 
408 	if (((h->flags & BDC_FLAG_VER_MASK) >> BDC_FLAG_VER_SHIFT) !=
409 	    BDC_PROTO_VER) {
410 		brcmf_dbg(ERROR, "%s: non-BDC packet received, flags 0x%x\n",
411 			  brcmf_ifname(drvr, *ifidx), h->flags);
412 		return -EBADE;
413 	}
414 
415 	if (h->flags & BDC_FLAG_SUM_GOOD) {
416 		brcmf_dbg(INFO, "%s: BDC packet received with good rx-csum, flags 0x%x\n",
417 			  brcmf_ifname(drvr, *ifidx), h->flags);
418 		pkt_set_sum_good(pktbuf, true);
419 	}
420 
421 	pktbuf->priority = h->priority & BDC_PRIORITY_MASK;
422 
423 	skb_pull(pktbuf, BDC_HEADER_LEN);
424 
425 	return 0;
426 }
427 
brcmf_proto_attach(struct brcmf_pub * drvr)428 int brcmf_proto_attach(struct brcmf_pub *drvr)
429 {
430 	struct brcmf_proto *cdc;
431 
432 	cdc = kzalloc(sizeof(struct brcmf_proto), GFP_ATOMIC);
433 	if (!cdc)
434 		goto fail;
435 
436 	/* ensure that the msg buf directly follows the cdc msg struct */
437 	if ((unsigned long)(&cdc->msg + 1) != (unsigned long)cdc->buf) {
438 		brcmf_dbg(ERROR, "struct brcmf_proto is not correctly defined\n");
439 		goto fail;
440 	}
441 
442 	drvr->prot = cdc;
443 	drvr->hdrlen += BDC_HEADER_LEN;
444 	drvr->bus_if->maxctl = BRCMF_DCMD_MAXLEN +
445 			sizeof(struct brcmf_proto_cdc_dcmd) + ROUND_UP_MARGIN;
446 	return 0;
447 
448 fail:
449 	kfree(cdc);
450 	return -ENOMEM;
451 }
452 
453 /* ~NOTE~ What if another thread is waiting on the semaphore?  Holding it? */
brcmf_proto_detach(struct brcmf_pub * drvr)454 void brcmf_proto_detach(struct brcmf_pub *drvr)
455 {
456 	kfree(drvr->prot);
457 	drvr->prot = NULL;
458 }
459 
brcmf_proto_init(struct brcmf_pub * drvr)460 int brcmf_proto_init(struct brcmf_pub *drvr)
461 {
462 	int ret = 0;
463 	char buf[128];
464 
465 	brcmf_dbg(TRACE, "Enter\n");
466 
467 	mutex_lock(&drvr->proto_block);
468 
469 	/* Get the device MAC address */
470 	strcpy(buf, "cur_etheraddr");
471 	ret = brcmf_proto_cdc_query_dcmd(drvr, 0, BRCMF_C_GET_VAR,
472 					  buf, sizeof(buf));
473 	if (ret < 0) {
474 		mutex_unlock(&drvr->proto_block);
475 		return ret;
476 	}
477 	memcpy(drvr->mac, buf, ETH_ALEN);
478 
479 	mutex_unlock(&drvr->proto_block);
480 
481 	ret = brcmf_c_preinit_dcmds(drvr);
482 
483 	/* Always assumes wl for now */
484 	drvr->iswl = true;
485 
486 	return ret;
487 }
488 
brcmf_proto_stop(struct brcmf_pub * drvr)489 void brcmf_proto_stop(struct brcmf_pub *drvr)
490 {
491 	/* Nothing to do for CDC */
492 }
493