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
37struct 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
78struct 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
97struct 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
106static 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
127static 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
145int
146brcmf_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
189retry:
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
224done:
225	return ret;
226}
227
228int 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
276done:
277	return ret;
278}
279
280int
281brcmf_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
344done:
345	mutex_unlock(&drvr->proto_block);
346
347	return ret;
348}
349
350static bool pkt_sum_needed(struct sk_buff *skb)
351{
352	return skb->ip_summed == CHECKSUM_PARTIAL;
353}
354
355static void pkt_set_sum_good(struct sk_buff *skb, bool x)
356{
357	skb->ip_summed = (x ? CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
358}
359
360void 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
383int 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
428int 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
448fail:
449	kfree(cdc);
450	return -ENOMEM;
451}
452
453/* ~NOTE~ What if another thread is waiting on the semaphore?  Holding it? */
454void brcmf_proto_detach(struct brcmf_pub *drvr)
455{
456	kfree(drvr->prot);
457	drvr->prot = NULL;
458}
459
460int 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
489void brcmf_proto_stop(struct brcmf_pub *drvr)
490{
491	/* Nothing to do for CDC */
492}
493