1 /*
2 * Atheros CARL9170 driver
3 *
4 * 802.11 & command trap routines
5 *
6 * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
7 * Copyright 2009, 2010, Christian Lamparter <chunkeey@googlemail.com>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; see the file COPYING. If not, see
21 * http://www.gnu.org/licenses/.
22 *
23 * This file incorporates work covered by the following copyright and
24 * permission notice:
25 * Copyright (c) 2007-2008 Atheros Communications, Inc.
26 *
27 * Permission to use, copy, modify, and/or distribute this software for any
28 * purpose with or without fee is hereby granted, provided that the above
29 * copyright notice and this permission notice appear in all copies.
30 *
31 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
32 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
33 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
34 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
35 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
36 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
37 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
38 */
39
40 #include <linux/slab.h>
41 #include <linux/module.h>
42 #include <linux/etherdevice.h>
43 #include <linux/crc32.h>
44 #include <net/mac80211.h>
45 #include "carl9170.h"
46 #include "hw.h"
47 #include "cmd.h"
48
carl9170_dbg_message(struct ar9170 * ar,const char * buf,u32 len)49 static void carl9170_dbg_message(struct ar9170 *ar, const char *buf, u32 len)
50 {
51 bool restart = false;
52 enum carl9170_restart_reasons reason = CARL9170_RR_NO_REASON;
53
54 if (len > 3) {
55 if (memcmp(buf, CARL9170_ERR_MAGIC, 3) == 0) {
56 ar->fw.err_counter++;
57 if (ar->fw.err_counter > 3) {
58 restart = true;
59 reason = CARL9170_RR_TOO_MANY_FIRMWARE_ERRORS;
60 }
61 }
62
63 if (memcmp(buf, CARL9170_BUG_MAGIC, 3) == 0) {
64 ar->fw.bug_counter++;
65 restart = true;
66 reason = CARL9170_RR_FATAL_FIRMWARE_ERROR;
67 }
68 }
69
70 wiphy_info(ar->hw->wiphy, "FW: %.*s\n", len, buf);
71
72 if (restart)
73 carl9170_restart(ar, reason);
74 }
75
carl9170_handle_ps(struct ar9170 * ar,struct carl9170_rsp * rsp)76 static void carl9170_handle_ps(struct ar9170 *ar, struct carl9170_rsp *rsp)
77 {
78 u32 ps;
79 bool new_ps;
80
81 ps = le32_to_cpu(rsp->psm.state);
82
83 new_ps = (ps & CARL9170_PSM_COUNTER) != CARL9170_PSM_WAKE;
84 if (ar->ps.state != new_ps) {
85 if (!new_ps) {
86 ar->ps.sleep_ms = jiffies_to_msecs(jiffies -
87 ar->ps.last_action);
88 }
89
90 ar->ps.last_action = jiffies;
91
92 ar->ps.state = new_ps;
93 }
94 }
95
carl9170_check_sequence(struct ar9170 * ar,unsigned int seq)96 static int carl9170_check_sequence(struct ar9170 *ar, unsigned int seq)
97 {
98 if (ar->cmd_seq < -1)
99 return 0;
100
101 /*
102 * Initialize Counter
103 */
104 if (ar->cmd_seq < 0)
105 ar->cmd_seq = seq;
106
107 /*
108 * The sequence is strictly monotonic increasing and it never skips!
109 *
110 * Therefore we can safely assume that whenever we received an
111 * unexpected sequence we have lost some valuable data.
112 */
113 if (seq != ar->cmd_seq) {
114 int count;
115
116 count = (seq - ar->cmd_seq) % ar->fw.cmd_bufs;
117
118 wiphy_err(ar->hw->wiphy, "lost %d command responses/traps! "
119 "w:%d g:%d\n", count, ar->cmd_seq, seq);
120
121 carl9170_restart(ar, CARL9170_RR_LOST_RSP);
122 return -EIO;
123 }
124
125 ar->cmd_seq = (ar->cmd_seq + 1) % ar->fw.cmd_bufs;
126 return 0;
127 }
128
carl9170_cmd_callback(struct ar9170 * ar,u32 len,void * buffer)129 static void carl9170_cmd_callback(struct ar9170 *ar, u32 len, void *buffer)
130 {
131 /*
132 * Some commands may have a variable response length
133 * and we cannot predict the correct length in advance.
134 * So we only check if we provided enough space for the data.
135 */
136 if (unlikely(ar->readlen != (len - 4))) {
137 dev_warn(&ar->udev->dev, "received invalid command response:"
138 "got %d, instead of %d\n", len - 4, ar->readlen);
139 print_hex_dump_bytes("carl9170 cmd:", DUMP_PREFIX_OFFSET,
140 ar->cmd_buf, (ar->cmd.hdr.len + 4) & 0x3f);
141 print_hex_dump_bytes("carl9170 rsp:", DUMP_PREFIX_OFFSET,
142 buffer, len);
143 /*
144 * Do not complete. The command times out,
145 * and we get a stack trace from there.
146 */
147 carl9170_restart(ar, CARL9170_RR_INVALID_RSP);
148 }
149
150 spin_lock(&ar->cmd_lock);
151 if (ar->readbuf) {
152 if (len >= 4)
153 memcpy(ar->readbuf, buffer + 4, len - 4);
154
155 ar->readbuf = NULL;
156 }
157 complete(&ar->cmd_wait);
158 spin_unlock(&ar->cmd_lock);
159 }
160
carl9170_handle_command_response(struct ar9170 * ar,void * buf,u32 len)161 void carl9170_handle_command_response(struct ar9170 *ar, void *buf, u32 len)
162 {
163 struct carl9170_rsp *cmd = buf;
164 struct ieee80211_vif *vif;
165
166 if ((cmd->hdr.cmd & CARL9170_RSP_FLAG) != CARL9170_RSP_FLAG) {
167 if (!(cmd->hdr.cmd & CARL9170_CMD_ASYNC_FLAG))
168 carl9170_cmd_callback(ar, len, buf);
169
170 return;
171 }
172
173 if (unlikely(cmd->hdr.len != (len - 4))) {
174 if (net_ratelimit()) {
175 wiphy_err(ar->hw->wiphy, "FW: received over-/under"
176 "sized event %x (%d, but should be %d).\n",
177 cmd->hdr.cmd, cmd->hdr.len, len - 4);
178
179 print_hex_dump_bytes("dump:", DUMP_PREFIX_NONE,
180 buf, len);
181 }
182
183 return;
184 }
185
186 /* hardware event handlers */
187 switch (cmd->hdr.cmd) {
188 case CARL9170_RSP_PRETBTT:
189 /* pre-TBTT event */
190 rcu_read_lock();
191 vif = carl9170_get_main_vif(ar);
192
193 if (!vif) {
194 rcu_read_unlock();
195 break;
196 }
197
198 switch (vif->type) {
199 case NL80211_IFTYPE_STATION:
200 carl9170_handle_ps(ar, cmd);
201 break;
202
203 case NL80211_IFTYPE_AP:
204 case NL80211_IFTYPE_ADHOC:
205 case NL80211_IFTYPE_MESH_POINT:
206 carl9170_update_beacon(ar, true);
207 break;
208
209 default:
210 break;
211 }
212 rcu_read_unlock();
213
214 break;
215
216
217 case CARL9170_RSP_TXCOMP:
218 /* TX status notification */
219 carl9170_tx_process_status(ar, cmd);
220 break;
221
222 case CARL9170_RSP_BEACON_CONFIG:
223 /*
224 * (IBSS) beacon send notification
225 * bytes: 04 c2 XX YY B4 B3 B2 B1
226 *
227 * XX always 80
228 * YY always 00
229 * B1-B4 "should" be the number of send out beacons.
230 */
231 break;
232
233 case CARL9170_RSP_ATIM:
234 /* End of Atim Window */
235 break;
236
237 case CARL9170_RSP_WATCHDOG:
238 /* Watchdog Interrupt */
239 carl9170_restart(ar, CARL9170_RR_WATCHDOG);
240 break;
241
242 case CARL9170_RSP_TEXT:
243 /* firmware debug */
244 carl9170_dbg_message(ar, (char *)buf + 4, len - 4);
245 break;
246
247 case CARL9170_RSP_HEXDUMP:
248 wiphy_dbg(ar->hw->wiphy, "FW: HD %d\n", len - 4);
249 print_hex_dump_bytes("FW:", DUMP_PREFIX_NONE,
250 (char *)buf + 4, len - 4);
251 break;
252
253 case CARL9170_RSP_RADAR:
254 if (!net_ratelimit())
255 break;
256
257 wiphy_info(ar->hw->wiphy, "FW: RADAR! Please report this "
258 "incident to linux-wireless@vger.kernel.org !\n");
259 break;
260
261 case CARL9170_RSP_GPIO:
262 #ifdef CONFIG_CARL9170_WPC
263 if (ar->wps.pbc) {
264 bool state = !!(cmd->gpio.gpio & cpu_to_le32(
265 AR9170_GPIO_PORT_WPS_BUTTON_PRESSED));
266
267 if (state != ar->wps.pbc_state) {
268 ar->wps.pbc_state = state;
269 input_report_key(ar->wps.pbc, KEY_WPS_BUTTON,
270 state);
271 input_sync(ar->wps.pbc);
272 }
273 }
274 #endif /* CONFIG_CARL9170_WPC */
275 break;
276
277 case CARL9170_RSP_BOOT:
278 complete(&ar->fw_boot_wait);
279 break;
280
281 default:
282 wiphy_err(ar->hw->wiphy, "FW: received unhandled event %x\n",
283 cmd->hdr.cmd);
284 print_hex_dump_bytes("dump:", DUMP_PREFIX_NONE, buf, len);
285 break;
286 }
287 }
288
carl9170_rx_mac_status(struct ar9170 * ar,struct ar9170_rx_head * head,struct ar9170_rx_macstatus * mac,struct ieee80211_rx_status * status)289 static int carl9170_rx_mac_status(struct ar9170 *ar,
290 struct ar9170_rx_head *head, struct ar9170_rx_macstatus *mac,
291 struct ieee80211_rx_status *status)
292 {
293 struct ieee80211_channel *chan;
294 u8 error, decrypt;
295
296 BUILD_BUG_ON(sizeof(struct ar9170_rx_head) != 12);
297 BUILD_BUG_ON(sizeof(struct ar9170_rx_macstatus) != 4);
298
299 error = mac->error;
300
301 if (error & AR9170_RX_ERROR_WRONG_RA) {
302 if (!ar->sniffer_enabled)
303 return -EINVAL;
304 }
305
306 if (error & AR9170_RX_ERROR_PLCP) {
307 if (!(ar->filter_state & FIF_PLCPFAIL))
308 return -EINVAL;
309
310 status->flag |= RX_FLAG_FAILED_PLCP_CRC;
311 }
312
313 if (error & AR9170_RX_ERROR_FCS) {
314 ar->tx_fcs_errors++;
315
316 if (!(ar->filter_state & FIF_FCSFAIL))
317 return -EINVAL;
318
319 status->flag |= RX_FLAG_FAILED_FCS_CRC;
320 }
321
322 decrypt = ar9170_get_decrypt_type(mac);
323 if (!(decrypt & AR9170_RX_ENC_SOFTWARE) &&
324 decrypt != AR9170_ENC_ALG_NONE) {
325 if ((decrypt == AR9170_ENC_ALG_TKIP) &&
326 (error & AR9170_RX_ERROR_MMIC))
327 status->flag |= RX_FLAG_MMIC_ERROR;
328
329 status->flag |= RX_FLAG_DECRYPTED;
330 }
331
332 if (error & AR9170_RX_ERROR_DECRYPT && !ar->sniffer_enabled)
333 return -ENODATA;
334
335 error &= ~(AR9170_RX_ERROR_MMIC |
336 AR9170_RX_ERROR_FCS |
337 AR9170_RX_ERROR_WRONG_RA |
338 AR9170_RX_ERROR_DECRYPT |
339 AR9170_RX_ERROR_PLCP);
340
341 /* drop any other error frames */
342 if (unlikely(error)) {
343 /* TODO: update netdevice's RX dropped/errors statistics */
344
345 if (net_ratelimit())
346 wiphy_dbg(ar->hw->wiphy, "received frame with "
347 "suspicious error code (%#x).\n", error);
348
349 return -EINVAL;
350 }
351
352 chan = ar->channel;
353 if (chan) {
354 status->band = chan->band;
355 status->freq = chan->center_freq;
356 }
357
358 switch (mac->status & AR9170_RX_STATUS_MODULATION) {
359 case AR9170_RX_STATUS_MODULATION_CCK:
360 if (mac->status & AR9170_RX_STATUS_SHORT_PREAMBLE)
361 status->enc_flags |= RX_ENC_FLAG_SHORTPRE;
362 switch (head->plcp[0]) {
363 case AR9170_RX_PHY_RATE_CCK_1M:
364 status->rate_idx = 0;
365 break;
366 case AR9170_RX_PHY_RATE_CCK_2M:
367 status->rate_idx = 1;
368 break;
369 case AR9170_RX_PHY_RATE_CCK_5M:
370 status->rate_idx = 2;
371 break;
372 case AR9170_RX_PHY_RATE_CCK_11M:
373 status->rate_idx = 3;
374 break;
375 default:
376 if (net_ratelimit()) {
377 wiphy_err(ar->hw->wiphy, "invalid plcp cck "
378 "rate (%x).\n", head->plcp[0]);
379 }
380
381 return -EINVAL;
382 }
383 break;
384
385 case AR9170_RX_STATUS_MODULATION_DUPOFDM:
386 case AR9170_RX_STATUS_MODULATION_OFDM:
387 switch (head->plcp[0] & 0xf) {
388 case AR9170_TXRX_PHY_RATE_OFDM_6M:
389 status->rate_idx = 0;
390 break;
391 case AR9170_TXRX_PHY_RATE_OFDM_9M:
392 status->rate_idx = 1;
393 break;
394 case AR9170_TXRX_PHY_RATE_OFDM_12M:
395 status->rate_idx = 2;
396 break;
397 case AR9170_TXRX_PHY_RATE_OFDM_18M:
398 status->rate_idx = 3;
399 break;
400 case AR9170_TXRX_PHY_RATE_OFDM_24M:
401 status->rate_idx = 4;
402 break;
403 case AR9170_TXRX_PHY_RATE_OFDM_36M:
404 status->rate_idx = 5;
405 break;
406 case AR9170_TXRX_PHY_RATE_OFDM_48M:
407 status->rate_idx = 6;
408 break;
409 case AR9170_TXRX_PHY_RATE_OFDM_54M:
410 status->rate_idx = 7;
411 break;
412 default:
413 if (net_ratelimit()) {
414 wiphy_err(ar->hw->wiphy, "invalid plcp ofdm "
415 "rate (%x).\n", head->plcp[0]);
416 }
417
418 return -EINVAL;
419 }
420 if (status->band == NL80211_BAND_2GHZ)
421 status->rate_idx += 4;
422 break;
423
424 case AR9170_RX_STATUS_MODULATION_HT:
425 if (head->plcp[3] & 0x80)
426 status->bw = RATE_INFO_BW_40;
427 if (head->plcp[6] & 0x80)
428 status->enc_flags |= RX_ENC_FLAG_SHORT_GI;
429
430 status->rate_idx = clamp(head->plcp[3] & 0x7f, 0, 75);
431 status->encoding = RX_ENC_HT;
432 break;
433
434 default:
435 BUG();
436 return -ENOSYS;
437 }
438
439 return 0;
440 }
441
carl9170_rx_phy_status(struct ar9170 * ar,struct ar9170_rx_phystatus * phy,struct ieee80211_rx_status * status)442 static void carl9170_rx_phy_status(struct ar9170 *ar,
443 struct ar9170_rx_phystatus *phy, struct ieee80211_rx_status *status)
444 {
445 int i;
446
447 BUILD_BUG_ON(sizeof(struct ar9170_rx_phystatus) != 20);
448
449 for (i = 0; i < 3; i++)
450 if (phy->rssi[i] != 0x80)
451 status->antenna |= BIT(i);
452
453 /* post-process RSSI */
454 for (i = 0; i < 7; i++)
455 if (phy->rssi[i] & 0x80)
456 phy->rssi[i] = ((~phy->rssi[i] & 0x7f) + 1) & 0x7f;
457
458 /* TODO: we could do something with phy_errors */
459 status->signal = ar->noise[0] + phy->rssi_combined;
460 }
461
carl9170_rx_copy_data(u8 * buf,int len)462 static struct sk_buff *carl9170_rx_copy_data(u8 *buf, int len)
463 {
464 struct sk_buff *skb;
465 int reserved = 0;
466 struct ieee80211_hdr *hdr = (void *) buf;
467
468 if (ieee80211_is_data_qos(hdr->frame_control)) {
469 u8 *qc = ieee80211_get_qos_ctl(hdr);
470 reserved += NET_IP_ALIGN;
471
472 if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
473 reserved += NET_IP_ALIGN;
474 }
475
476 if (ieee80211_has_a4(hdr->frame_control))
477 reserved += NET_IP_ALIGN;
478
479 reserved = 32 + (reserved & NET_IP_ALIGN);
480
481 skb = dev_alloc_skb(len + reserved);
482 if (likely(skb)) {
483 skb_reserve(skb, reserved);
484 skb_put_data(skb, buf, len);
485 }
486
487 return skb;
488 }
489
carl9170_find_ie(u8 * data,unsigned int len,u8 ie)490 static u8 *carl9170_find_ie(u8 *data, unsigned int len, u8 ie)
491 {
492 struct ieee80211_mgmt *mgmt = (void *)data;
493 u8 *pos, *end;
494
495 pos = (u8 *)mgmt->u.beacon.variable;
496 end = data + len;
497 while (pos < end) {
498 if (pos + 2 + pos[1] > end)
499 return NULL;
500
501 if (pos[0] == ie)
502 return pos;
503
504 pos += 2 + pos[1];
505 }
506 return NULL;
507 }
508
509 /*
510 * NOTE:
511 *
512 * The firmware is in charge of waking up the device just before
513 * the AP is expected to transmit the next beacon.
514 *
515 * This leaves the driver with the important task of deciding when
516 * to set the PHY back to bed again.
517 */
carl9170_ps_beacon(struct ar9170 * ar,void * data,unsigned int len)518 static void carl9170_ps_beacon(struct ar9170 *ar, void *data, unsigned int len)
519 {
520 struct ieee80211_hdr *hdr = data;
521 struct ieee80211_tim_ie *tim_ie;
522 struct ath_common *common = &ar->common;
523 u8 *tim;
524 u8 tim_len;
525 bool cam;
526
527 if (likely(!(ar->hw->conf.flags & IEEE80211_CONF_PS)))
528 return;
529
530 /* min. beacon length + FCS_LEN */
531 if (len <= 40 + FCS_LEN)
532 return;
533
534 /* check if this really is a beacon */
535 /* and only beacons from the associated BSSID, please */
536 if (!ath_is_mybeacon(common, hdr) || !common->curaid)
537 return;
538
539 ar->ps.last_beacon = jiffies;
540
541 tim = carl9170_find_ie(data, len - FCS_LEN, WLAN_EID_TIM);
542 if (!tim)
543 return;
544
545 if (tim[1] < sizeof(*tim_ie))
546 return;
547
548 tim_len = tim[1];
549 tim_ie = (struct ieee80211_tim_ie *) &tim[2];
550
551 if (!WARN_ON_ONCE(!ar->hw->conf.ps_dtim_period))
552 ar->ps.dtim_counter = (tim_ie->dtim_count - 1) %
553 ar->hw->conf.ps_dtim_period;
554
555 /* Check whenever the PHY can be turned off again. */
556
557 /* 1. What about buffered unicast traffic for our AID? */
558 cam = ieee80211_check_tim(tim_ie, tim_len, ar->common.curaid);
559
560 /* 2. Maybe the AP wants to send multicast/broadcast data? */
561 cam |= !!(tim_ie->bitmap_ctrl & 0x01);
562
563 if (!cam) {
564 /* back to low-power land. */
565 ar->ps.off_override &= ~PS_OFF_BCN;
566 carl9170_ps_check(ar);
567 } else {
568 /* force CAM */
569 ar->ps.off_override |= PS_OFF_BCN;
570 }
571 }
572
carl9170_ba_check(struct ar9170 * ar,void * data,unsigned int len)573 static void carl9170_ba_check(struct ar9170 *ar, void *data, unsigned int len)
574 {
575 struct ieee80211_bar *bar = data;
576 struct carl9170_bar_list_entry *entry;
577 unsigned int queue;
578
579 if (likely(!ieee80211_is_back(bar->frame_control)))
580 return;
581
582 if (len <= sizeof(*bar) + FCS_LEN)
583 return;
584
585 queue = TID_TO_WME_AC(((le16_to_cpu(bar->control) &
586 IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
587 IEEE80211_BAR_CTRL_TID_INFO_SHIFT) & 7);
588
589 rcu_read_lock();
590 list_for_each_entry_rcu(entry, &ar->bar_list[queue], list) {
591 struct sk_buff *entry_skb = entry->skb;
592 struct _carl9170_tx_superframe *super = (void *)entry_skb->data;
593 struct ieee80211_bar *entry_bar = (void *)super->frame_data;
594
595 #define TID_CHECK(a, b) ( \
596 ((a) & cpu_to_le16(IEEE80211_BAR_CTRL_TID_INFO_MASK)) == \
597 ((b) & cpu_to_le16(IEEE80211_BAR_CTRL_TID_INFO_MASK))) \
598
599 if (bar->start_seq_num == entry_bar->start_seq_num &&
600 TID_CHECK(bar->control, entry_bar->control) &&
601 ether_addr_equal_64bits(bar->ra, entry_bar->ta) &&
602 ether_addr_equal_64bits(bar->ta, entry_bar->ra)) {
603 struct ieee80211_tx_info *tx_info;
604
605 tx_info = IEEE80211_SKB_CB(entry_skb);
606 tx_info->flags |= IEEE80211_TX_STAT_ACK;
607
608 spin_lock_bh(&ar->bar_list_lock[queue]);
609 list_del_rcu(&entry->list);
610 spin_unlock_bh(&ar->bar_list_lock[queue]);
611 kfree_rcu(entry, head);
612 break;
613 }
614 }
615 rcu_read_unlock();
616
617 #undef TID_CHECK
618 }
619
carl9170_ampdu_check(struct ar9170 * ar,u8 * buf,u8 ms,struct ieee80211_rx_status * rx_status)620 static bool carl9170_ampdu_check(struct ar9170 *ar, u8 *buf, u8 ms,
621 struct ieee80211_rx_status *rx_status)
622 {
623 __le16 fc;
624
625 if ((ms & AR9170_RX_STATUS_MPDU) == AR9170_RX_STATUS_MPDU_SINGLE) {
626 /*
627 * This frame is not part of an aMPDU.
628 * Therefore it is not subjected to any
629 * of the following content restrictions.
630 */
631 return true;
632 }
633
634 rx_status->flag |= RX_FLAG_AMPDU_DETAILS | RX_FLAG_AMPDU_LAST_KNOWN;
635 rx_status->ampdu_reference = ar->ampdu_ref;
636
637 /*
638 * "802.11n - 7.4a.3 A-MPDU contents" describes in which contexts
639 * certain frame types can be part of an aMPDU.
640 *
641 * In order to keep the processing cost down, I opted for a
642 * stateless filter solely based on the frame control field.
643 */
644
645 fc = ((struct ieee80211_hdr *)buf)->frame_control;
646 if (ieee80211_is_data_qos(fc) && ieee80211_is_data_present(fc))
647 return true;
648
649 if (ieee80211_is_ack(fc) || ieee80211_is_back(fc) ||
650 ieee80211_is_back_req(fc))
651 return true;
652
653 if (ieee80211_is_action(fc))
654 return true;
655
656 return false;
657 }
658
carl9170_handle_mpdu(struct ar9170 * ar,u8 * buf,int len,struct ieee80211_rx_status * status)659 static int carl9170_handle_mpdu(struct ar9170 *ar, u8 *buf, int len,
660 struct ieee80211_rx_status *status)
661 {
662 struct sk_buff *skb;
663
664 /* (driver) frame trap handler
665 *
666 * Because power-saving mode handing has to be implemented by
667 * the driver/firmware. We have to check each incoming beacon
668 * from the associated AP, if there's new data for us (either
669 * broadcast/multicast or unicast) we have to react quickly.
670 *
671 * So, if you have you want to add additional frame trap
672 * handlers, this would be the perfect place!
673 */
674
675 carl9170_ps_beacon(ar, buf, len);
676
677 carl9170_ba_check(ar, buf, len);
678
679 skb = carl9170_rx_copy_data(buf, len);
680 if (!skb)
681 return -ENOMEM;
682
683 memcpy(IEEE80211_SKB_RXCB(skb), status, sizeof(*status));
684 ieee80211_rx(ar->hw, skb);
685 return 0;
686 }
687
688 /*
689 * If the frame alignment is right (or the kernel has
690 * CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS), and there
691 * is only a single MPDU in the USB frame, then we could
692 * submit to mac80211 the SKB directly. However, since
693 * there may be multiple packets in one SKB in stream
694 * mode, and we need to observe the proper ordering,
695 * this is non-trivial.
696 */
carl9170_rx_untie_data(struct ar9170 * ar,u8 * buf,int len)697 static void carl9170_rx_untie_data(struct ar9170 *ar, u8 *buf, int len)
698 {
699 struct ar9170_rx_head *head;
700 struct ar9170_rx_macstatus *mac;
701 struct ar9170_rx_phystatus *phy = NULL;
702 struct ieee80211_rx_status status;
703 int mpdu_len;
704 u8 mac_status;
705
706 if (!IS_STARTED(ar))
707 return;
708
709 if (unlikely(len < sizeof(*mac)))
710 goto drop;
711
712 memset(&status, 0, sizeof(status));
713
714 mpdu_len = len - sizeof(*mac);
715
716 mac = (void *)(buf + mpdu_len);
717 mac_status = mac->status;
718 switch (mac_status & AR9170_RX_STATUS_MPDU) {
719 case AR9170_RX_STATUS_MPDU_FIRST:
720 ar->ampdu_ref++;
721 /* Aggregated MPDUs start with an PLCP header */
722 if (likely(mpdu_len >= sizeof(struct ar9170_rx_head))) {
723 head = (void *) buf;
724
725 /*
726 * The PLCP header needs to be cached for the
727 * following MIDDLE + LAST A-MPDU packets.
728 *
729 * So, if you are wondering why all frames seem
730 * to share a common RX status information,
731 * then you have the answer right here...
732 */
733 memcpy(&ar->rx_plcp, (void *) buf,
734 sizeof(struct ar9170_rx_head));
735
736 mpdu_len -= sizeof(struct ar9170_rx_head);
737 buf += sizeof(struct ar9170_rx_head);
738
739 ar->rx_has_plcp = true;
740 } else {
741 if (net_ratelimit()) {
742 wiphy_err(ar->hw->wiphy, "plcp info "
743 "is clipped.\n");
744 }
745
746 goto drop;
747 }
748 break;
749
750 case AR9170_RX_STATUS_MPDU_LAST:
751 status.flag |= RX_FLAG_AMPDU_IS_LAST;
752
753 /*
754 * The last frame of an A-MPDU has an extra tail
755 * which does contain the phy status of the whole
756 * aggregate.
757 */
758 if (likely(mpdu_len >= sizeof(struct ar9170_rx_phystatus))) {
759 mpdu_len -= sizeof(struct ar9170_rx_phystatus);
760 phy = (void *)(buf + mpdu_len);
761 } else {
762 if (net_ratelimit()) {
763 wiphy_err(ar->hw->wiphy, "frame tail "
764 "is clipped.\n");
765 }
766
767 goto drop;
768 }
769 fallthrough;
770
771 case AR9170_RX_STATUS_MPDU_MIDDLE:
772 /* These are just data + mac status */
773 if (unlikely(!ar->rx_has_plcp)) {
774 if (!net_ratelimit())
775 return;
776
777 wiphy_err(ar->hw->wiphy, "rx stream does not start "
778 "with a first_mpdu frame tag.\n");
779
780 goto drop;
781 }
782
783 head = &ar->rx_plcp;
784 break;
785
786 case AR9170_RX_STATUS_MPDU_SINGLE:
787 /* single mpdu has both: plcp (head) and phy status (tail) */
788 head = (void *) buf;
789
790 mpdu_len -= sizeof(struct ar9170_rx_head);
791 mpdu_len -= sizeof(struct ar9170_rx_phystatus);
792
793 buf += sizeof(struct ar9170_rx_head);
794 phy = (void *)(buf + mpdu_len);
795 break;
796
797 default:
798 BUG();
799 break;
800 }
801
802 /* FC + DU + RA + FCS */
803 if (unlikely(mpdu_len < (2 + 2 + ETH_ALEN + FCS_LEN)))
804 goto drop;
805
806 if (unlikely(carl9170_rx_mac_status(ar, head, mac, &status)))
807 goto drop;
808
809 if (!carl9170_ampdu_check(ar, buf, mac_status, &status))
810 goto drop;
811
812 if (phy)
813 carl9170_rx_phy_status(ar, phy, &status);
814 else
815 status.flag |= RX_FLAG_NO_SIGNAL_VAL;
816
817 if (carl9170_handle_mpdu(ar, buf, mpdu_len, &status))
818 goto drop;
819
820 return;
821 drop:
822 ar->rx_dropped++;
823 }
824
carl9170_rx_untie_cmds(struct ar9170 * ar,const u8 * respbuf,const unsigned int resplen)825 static void carl9170_rx_untie_cmds(struct ar9170 *ar, const u8 *respbuf,
826 const unsigned int resplen)
827 {
828 struct carl9170_rsp *cmd;
829 int i = 0;
830
831 while (i < resplen) {
832 cmd = (void *) &respbuf[i];
833
834 i += cmd->hdr.len + 4;
835 if (unlikely(i > resplen))
836 break;
837
838 if (carl9170_check_sequence(ar, cmd->hdr.seq))
839 break;
840
841 carl9170_handle_command_response(ar, cmd, cmd->hdr.len + 4);
842 }
843
844 if (unlikely(i != resplen)) {
845 if (!net_ratelimit())
846 return;
847
848 wiphy_err(ar->hw->wiphy, "malformed firmware trap:\n");
849 print_hex_dump_bytes("rxcmd:", DUMP_PREFIX_OFFSET,
850 respbuf, resplen);
851 }
852 }
853
__carl9170_rx(struct ar9170 * ar,u8 * buf,unsigned int len)854 static void __carl9170_rx(struct ar9170 *ar, u8 *buf, unsigned int len)
855 {
856 unsigned int i = 0;
857
858 /* weird thing, but this is the same in the original driver */
859 while (len > 2 && i < 12 && buf[0] == 0xff && buf[1] == 0xff) {
860 i += 2;
861 len -= 2;
862 buf += 2;
863 }
864
865 if (unlikely(len < 4))
866 return;
867
868 /* found the 6 * 0xffff marker? */
869 if (i == 12)
870 carl9170_rx_untie_cmds(ar, buf, len);
871 else
872 carl9170_rx_untie_data(ar, buf, len);
873 }
874
carl9170_rx_stream(struct ar9170 * ar,void * buf,unsigned int len)875 static void carl9170_rx_stream(struct ar9170 *ar, void *buf, unsigned int len)
876 {
877 unsigned int tlen, wlen = 0, clen = 0;
878 struct ar9170_stream *rx_stream;
879 u8 *tbuf;
880
881 tbuf = buf;
882 tlen = len;
883
884 while (tlen >= 4) {
885 rx_stream = (void *) tbuf;
886 clen = le16_to_cpu(rx_stream->length);
887 wlen = ALIGN(clen, 4);
888
889 /* check if this is stream has a valid tag.*/
890 if (rx_stream->tag != cpu_to_le16(AR9170_RX_STREAM_TAG)) {
891 /*
892 * TODO: handle the highly unlikely event that the
893 * corrupted stream has the TAG at the right position.
894 */
895
896 /* check if the frame can be repaired. */
897 if (!ar->rx_failover_missing) {
898
899 /* this is not "short read". */
900 if (net_ratelimit()) {
901 wiphy_err(ar->hw->wiphy,
902 "missing tag!\n");
903 }
904
905 __carl9170_rx(ar, tbuf, tlen);
906 return;
907 }
908
909 if (ar->rx_failover_missing > tlen) {
910 if (net_ratelimit()) {
911 wiphy_err(ar->hw->wiphy,
912 "possible multi "
913 "stream corruption!\n");
914 goto err_telluser;
915 } else {
916 goto err_silent;
917 }
918 }
919
920 skb_put_data(ar->rx_failover, tbuf, tlen);
921 ar->rx_failover_missing -= tlen;
922
923 if (ar->rx_failover_missing <= 0) {
924 /*
925 * nested carl9170_rx_stream call!
926 *
927 * termination is guaranteed, even when the
928 * combined frame also have an element with
929 * a bad tag.
930 */
931
932 ar->rx_failover_missing = 0;
933 carl9170_rx_stream(ar, ar->rx_failover->data,
934 ar->rx_failover->len);
935
936 skb_reset_tail_pointer(ar->rx_failover);
937 skb_trim(ar->rx_failover, 0);
938 }
939
940 return;
941 }
942
943 /* check if stream is clipped */
944 if (wlen > tlen - 4) {
945 if (ar->rx_failover_missing) {
946 /* TODO: handle double stream corruption. */
947 if (net_ratelimit()) {
948 wiphy_err(ar->hw->wiphy, "double rx "
949 "stream corruption!\n");
950 goto err_telluser;
951 } else {
952 goto err_silent;
953 }
954 }
955
956 /*
957 * save incomplete data set.
958 * the firmware will resend the missing bits when
959 * the rx - descriptor comes round again.
960 */
961
962 skb_put_data(ar->rx_failover, tbuf, tlen);
963 ar->rx_failover_missing = clen - tlen;
964 return;
965 }
966 __carl9170_rx(ar, rx_stream->payload, clen);
967
968 tbuf += wlen + 4;
969 tlen -= wlen + 4;
970 }
971
972 if (tlen) {
973 if (net_ratelimit()) {
974 wiphy_err(ar->hw->wiphy, "%d bytes of unprocessed "
975 "data left in rx stream!\n", tlen);
976 }
977
978 goto err_telluser;
979 }
980
981 return;
982
983 err_telluser:
984 wiphy_err(ar->hw->wiphy, "damaged RX stream data [want:%d, "
985 "data:%d, rx:%d, pending:%d ]\n", clen, wlen, tlen,
986 ar->rx_failover_missing);
987
988 if (ar->rx_failover_missing)
989 print_hex_dump_bytes("rxbuf:", DUMP_PREFIX_OFFSET,
990 ar->rx_failover->data,
991 ar->rx_failover->len);
992
993 print_hex_dump_bytes("stream:", DUMP_PREFIX_OFFSET,
994 buf, len);
995
996 wiphy_err(ar->hw->wiphy, "please check your hardware and cables, if "
997 "you see this message frequently.\n");
998
999 err_silent:
1000 if (ar->rx_failover_missing) {
1001 skb_reset_tail_pointer(ar->rx_failover);
1002 skb_trim(ar->rx_failover, 0);
1003 ar->rx_failover_missing = 0;
1004 }
1005 }
1006
carl9170_rx(struct ar9170 * ar,void * buf,unsigned int len)1007 void carl9170_rx(struct ar9170 *ar, void *buf, unsigned int len)
1008 {
1009 if (ar->fw.rx_stream)
1010 carl9170_rx_stream(ar, buf, len);
1011 else
1012 __carl9170_rx(ar, buf, len);
1013 }
1014