git.oblomov.eu Git - linux-2.6/blob - drivers/net/wireless/zd1211rw/zd_mac.c

   1 /* ZD1211 USB-WLAN driver for Linux
   2  *
   3  * Copyright (C) 2005-2007 Ulrich Kunitz <kune@deine-taler.de>
   4  * Copyright (C) 2006-2007 Daniel Drake <dsd@gentoo.org>
   5  * Copyright (C) 2006-2007 Michael Wu <flamingice@sourmilk.net>
   6  * Copyright (C) 2007-2008 Luis R. Rodriguez <mcgrof@winlab.rutgers.edu>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21  */
  22
  23 #include <linux/netdevice.h>
  24 #include <linux/etherdevice.h>
  25 #include <linux/usb.h>
  26 #include <linux/jiffies.h>
  27 #include <net/ieee80211_radiotap.h>
  28
  29 #include "zd_def.h"
  30 #include "zd_chip.h"
  31 #include "zd_mac.h"
  32 #include "zd_rf.h"
  33
  34 struct zd_reg_alpha2_map {
  35         u32 reg;
  36         char alpha2[2];
  37 };
  38
  39 static struct zd_reg_alpha2_map reg_alpha2_map[] = {
  40         { ZD_REGDOMAIN_FCC, "US" },
  41         { ZD_REGDOMAIN_IC, "CA" },
  42         { ZD_REGDOMAIN_ETSI, "DE" }, /* Generic ETSI, use most restrictive */
  43         { ZD_REGDOMAIN_JAPAN, "JP" },
  44         { ZD_REGDOMAIN_JAPAN_ADD, "JP" },
  45         { ZD_REGDOMAIN_SPAIN, "ES" },
  46         { ZD_REGDOMAIN_FRANCE, "FR" },
  47 };
  48
  49 /* This table contains the hardware specific values for the modulation rates. */
  50 static const struct ieee80211_rate zd_rates[] = {
  51         { .bitrate = 10,
  52           .hw_value = ZD_CCK_RATE_1M, },
  53         { .bitrate = 20,
  54           .hw_value = ZD_CCK_RATE_2M,
  55           .hw_value_short = ZD_CCK_RATE_2M | ZD_CCK_PREA_SHORT,
  56           .flags = IEEE80211_RATE_SHORT_PREAMBLE },
  57         { .bitrate = 55,
  58           .hw_value = ZD_CCK_RATE_5_5M,
  59           .hw_value_short = ZD_CCK_RATE_5_5M | ZD_CCK_PREA_SHORT,
  60           .flags = IEEE80211_RATE_SHORT_PREAMBLE },
  61         { .bitrate = 110,
  62           .hw_value = ZD_CCK_RATE_11M,
  63           .hw_value_short = ZD_CCK_RATE_11M | ZD_CCK_PREA_SHORT,
  64           .flags = IEEE80211_RATE_SHORT_PREAMBLE },
  65         { .bitrate = 60,
  66           .hw_value = ZD_OFDM_RATE_6M,
  67           .flags = 0 },
  68         { .bitrate = 90,
  69           .hw_value = ZD_OFDM_RATE_9M,
  70           .flags = 0 },
  71         { .bitrate = 120,
  72           .hw_value = ZD_OFDM_RATE_12M,
  73           .flags = 0 },
  74         { .bitrate = 180,
  75           .hw_value = ZD_OFDM_RATE_18M,
  76           .flags = 0 },
  77         { .bitrate = 240,
  78           .hw_value = ZD_OFDM_RATE_24M,
  79           .flags = 0 },
  80         { .bitrate = 360,
  81           .hw_value = ZD_OFDM_RATE_36M,
  82           .flags = 0 },
  83         { .bitrate = 480,
  84           .hw_value = ZD_OFDM_RATE_48M,
  85           .flags = 0 },
  86         { .bitrate = 540,
  87           .hw_value = ZD_OFDM_RATE_54M,
  88           .flags = 0 },
  89 };
  90
  91 static const struct ieee80211_channel zd_channels[] = {
  92         { .center_freq = 2412, .hw_value = 1 },
  93         { .center_freq = 2417, .hw_value = 2 },
  94         { .center_freq = 2422, .hw_value = 3 },
  95         { .center_freq = 2427, .hw_value = 4 },
  96         { .center_freq = 2432, .hw_value = 5 },
  97         { .center_freq = 2437, .hw_value = 6 },
  98         { .center_freq = 2442, .hw_value = 7 },
  99         { .center_freq = 2447, .hw_value = 8 },
 100         { .center_freq = 2452, .hw_value = 9 },
 101         { .center_freq = 2457, .hw_value = 10 },
 102         { .center_freq = 2462, .hw_value = 11 },
 103         { .center_freq = 2467, .hw_value = 12 },
 104         { .center_freq = 2472, .hw_value = 13 },
 105         { .center_freq = 2484, .hw_value = 14 },
 106 };
 107
 108 static void housekeeping_init(struct zd_mac *mac);
 109 static void housekeeping_enable(struct zd_mac *mac);
 110 static void housekeeping_disable(struct zd_mac *mac);
 111
 112 static int zd_reg2alpha2(u8 regdomain, char *alpha2)
 113 {
 114         unsigned int i;
 115         struct zd_reg_alpha2_map *reg_map;
 116         for (i = 0; i < ARRAY_SIZE(reg_alpha2_map); i++) {
 117                 reg_map = &reg_alpha2_map[i];
 118                 if (regdomain == reg_map->reg) {
 119                         alpha2[0] = reg_map->alpha2[0];
 120                         alpha2[1] = reg_map->alpha2[1];
 121                         return 0;
 122                 }
 123         }
 124         return 1;
 125 }
 126
 127 int zd_mac_preinit_hw(struct ieee80211_hw *hw)
 128 {
 129         int r;
 130         u8 addr[ETH_ALEN];
 131         struct zd_mac *mac = zd_hw_mac(hw);
 132
 133         r = zd_chip_read_mac_addr_fw(&mac->chip, addr);
 134         if (r)
 135                 return r;
 136
 137         SET_IEEE80211_PERM_ADDR(hw, addr);
 138
 139         return 0;
 140 }
 141
 142 int zd_mac_init_hw(struct ieee80211_hw *hw)
 143 {
 144         int r;
 145         struct zd_mac *mac = zd_hw_mac(hw);
 146         struct zd_chip *chip = &mac->chip;
 147         char alpha2[2];
 148         u8 default_regdomain;
 149
 150         r = zd_chip_enable_int(chip);
 151         if (r)
 152                 goto out;
 153         r = zd_chip_init_hw(chip);
 154         if (r)
 155                 goto disable_int;
 156
 157         ZD_ASSERT(!irqs_disabled());
 158
 159         r = zd_read_regdomain(chip, &default_regdomain);
 160         if (r)
 161                 goto disable_int;
 162         spin_lock_irq(&mac->lock);
 163         mac->regdomain = mac->default_regdomain = default_regdomain;
 164         spin_unlock_irq(&mac->lock);
 165
 166         /* We must inform the device that we are doing encryption/decryption in
 167          * software at the moment. */
 168         r = zd_set_encryption_type(chip, ENC_SNIFFER);
 169         if (r)
 170                 goto disable_int;
 171
 172         r = zd_reg2alpha2(mac->regdomain, alpha2);
 173         if (!r)
 174                 regulatory_hint(hw->wiphy, alpha2);
 175
 176         r = 0;
 177 disable_int:
 178         zd_chip_disable_int(chip);
 179 out:
 180         return r;
 181 }
 182
 183 void zd_mac_clear(struct zd_mac *mac)
 184 {
 185         flush_workqueue(zd_workqueue);
 186         zd_chip_clear(&mac->chip);
 187         ZD_ASSERT(!spin_is_locked(&mac->lock));
 188         ZD_MEMCLEAR(mac, sizeof(struct zd_mac));
 189 }
 190
 191 static int set_rx_filter(struct zd_mac *mac)
 192 {
 193         unsigned long flags;
 194         u32 filter = STA_RX_FILTER;
 195
 196         spin_lock_irqsave(&mac->lock, flags);
 197         if (mac->pass_ctrl)
 198                 filter |= RX_FILTER_CTRL;
 199         spin_unlock_irqrestore(&mac->lock, flags);
 200
 201         return zd_iowrite32(&mac->chip, CR_RX_FILTER, filter);
 202 }
 203
 204 static int set_mc_hash(struct zd_mac *mac)
 205 {
 206         struct zd_mc_hash hash;
 207         zd_mc_clear(&hash);
 208         return zd_chip_set_multicast_hash(&mac->chip, &hash);
 209 }
 210
 211 static int zd_op_start(struct ieee80211_hw *hw)
 212 {
 213         struct zd_mac *mac = zd_hw_mac(hw);
 214         struct zd_chip *chip = &mac->chip;
 215         struct zd_usb *usb = &chip->usb;
 216         int r;
 217
 218         if (!usb->initialized) {
 219                 r = zd_usb_init_hw(usb);
 220                 if (r)
 221                         goto out;
 222         }
 223
 224         r = zd_chip_enable_int(chip);
 225         if (r < 0)
 226                 goto out;
 227
 228         r = zd_chip_set_basic_rates(chip, CR_RATES_80211B | CR_RATES_80211G);
 229         if (r < 0)
 230                 goto disable_int;
 231         r = set_rx_filter(mac);
 232         if (r)
 233                 goto disable_int;
 234         r = set_mc_hash(mac);
 235         if (r)
 236                 goto disable_int;
 237         r = zd_chip_switch_radio_on(chip);
 238         if (r < 0)
 239                 goto disable_int;
 240         r = zd_chip_enable_rxtx(chip);
 241         if (r < 0)
 242                 goto disable_radio;
 243         r = zd_chip_enable_hwint(chip);
 244         if (r < 0)
 245                 goto disable_rxtx;
 246
 247         housekeeping_enable(mac);
 248         return 0;
 249 disable_rxtx:
 250         zd_chip_disable_rxtx(chip);
 251 disable_radio:
 252         zd_chip_switch_radio_off(chip);
 253 disable_int:
 254         zd_chip_disable_int(chip);
 255 out:
 256         return r;
 257 }
 258
 259 static void zd_op_stop(struct ieee80211_hw *hw)
 260 {
 261         struct zd_mac *mac = zd_hw_mac(hw);
 262         struct zd_chip *chip = &mac->chip;
 263         struct sk_buff *skb;
 264         struct sk_buff_head *ack_wait_queue = &mac->ack_wait_queue;
 265
 266         /* The order here deliberately is a little different from the open()
 267          * method, since we need to make sure there is no opportunity for RX
 268          * frames to be processed by mac80211 after we have stopped it.
 269          */
 270
 271         zd_chip_disable_rxtx(chip);
 272         housekeeping_disable(mac);
 273         flush_workqueue(zd_workqueue);
 274
 275         zd_chip_disable_hwint(chip);
 276         zd_chip_switch_radio_off(chip);
 277         zd_chip_disable_int(chip);
 278
 279
 280         while ((skb = skb_dequeue(ack_wait_queue)))
 281                 dev_kfree_skb_any(skb);
 282 }
 283
 284 /**
 285  * tx_status - reports tx status of a packet if required
 286  * @hw - a &struct ieee80211_hw pointer
 287  * @skb - a sk-buffer
 288  * @flags: extra flags to set in the TX status info
 289  * @ackssi: ACK signal strength
 290  * @success - True for successful transmission of the frame
 291  *
 292  * This information calls ieee80211_tx_status_irqsafe() if required by the
 293  * control information. It copies the control information into the status
 294  * information.
 295  *
 296  * If no status information has been requested, the skb is freed.
 297  */
 298 static void tx_status(struct ieee80211_hw *hw, struct sk_buff *skb,
 299                       int ackssi, bool success)
 300 {
 301         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 302
 303         ieee80211_tx_info_clear_status(info);
 304
 305         if (success)
 306                 info->flags |= IEEE80211_TX_STAT_ACK;
 307         info->status.ack_signal = ackssi;
 308         ieee80211_tx_status_irqsafe(hw, skb);
 309 }
 310
 311 /**
 312  * zd_mac_tx_failed - callback for failed frames
 313  * @dev: the mac80211 wireless device
 314  *
 315  * This function is called if a frame couldn't be succesfully be
 316  * transferred. The first frame from the tx queue, will be selected and
 317  * reported as error to the upper layers.
 318  */
 319 void zd_mac_tx_failed(struct ieee80211_hw *hw)
 320 {
 321         struct sk_buff_head *q = &zd_hw_mac(hw)->ack_wait_queue;
 322         struct sk_buff *skb;
 323
 324         skb = skb_dequeue(q);
 325         if (skb == NULL)
 326                 return;
 327
 328         tx_status(hw, skb, 0, 0);
 329 }
 330
 331 /**
 332  * zd_mac_tx_to_dev - callback for USB layer
 333  * @skb: a &sk_buff pointer
 334  * @error: error value, 0 if transmission successful
 335  *
 336  * Informs the MAC layer that the frame has successfully transferred to the
 337  * device. If an ACK is required and the transfer to the device has been
 338  * successful, the packets are put on the @ack_wait_queue with
 339  * the control set removed.
 340  */
 341 void zd_mac_tx_to_dev(struct sk_buff *skb, int error)
 342 {
 343         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 344         struct ieee80211_hw *hw = info->rate_driver_data[0];
 345
 346         skb_pull(skb, sizeof(struct zd_ctrlset));
 347         if (unlikely(error ||
 348             (info->flags & IEEE80211_TX_CTL_NO_ACK))) {
 349                 tx_status(hw, skb, 0, !error);
 350         } else {
 351                 struct sk_buff_head *q =
 352                         &zd_hw_mac(hw)->ack_wait_queue;
 353
 354                 skb_queue_tail(q, skb);
 355                 while (skb_queue_len(q) > ZD_MAC_MAX_ACK_WAITERS)
 356                         zd_mac_tx_failed(hw);
 357         }
 358 }
 359
 360 static int zd_calc_tx_length_us(u8 *service, u8 zd_rate, u16 tx_length)
 361 {
 362         /* ZD_PURE_RATE() must be used to remove the modulation type flag of
 363          * the zd-rate values.
 364          */
 365         static const u8 rate_divisor[] = {
 366                 [ZD_PURE_RATE(ZD_CCK_RATE_1M)]   =  1,
 367                 [ZD_PURE_RATE(ZD_CCK_RATE_2M)]   =  2,
 368                 /* Bits must be doubled. */
 369                 [ZD_PURE_RATE(ZD_CCK_RATE_5_5M)] = 11,
 370                 [ZD_PURE_RATE(ZD_CCK_RATE_11M)]  = 11,
 371                 [ZD_PURE_RATE(ZD_OFDM_RATE_6M)]  =  6,
 372                 [ZD_PURE_RATE(ZD_OFDM_RATE_9M)]  =  9,
 373                 [ZD_PURE_RATE(ZD_OFDM_RATE_12M)] = 12,
 374                 [ZD_PURE_RATE(ZD_OFDM_RATE_18M)] = 18,
 375                 [ZD_PURE_RATE(ZD_OFDM_RATE_24M)] = 24,
 376                 [ZD_PURE_RATE(ZD_OFDM_RATE_36M)] = 36,
 377                 [ZD_PURE_RATE(ZD_OFDM_RATE_48M)] = 48,
 378                 [ZD_PURE_RATE(ZD_OFDM_RATE_54M)] = 54,
 379         };
 380
 381         u32 bits = (u32)tx_length * 8;
 382         u32 divisor;
 383
 384         divisor = rate_divisor[ZD_PURE_RATE(zd_rate)];
 385         if (divisor == 0)
 386                 return -EINVAL;
 387
 388         switch (zd_rate) {
 389         case ZD_CCK_RATE_5_5M:
 390                 bits = (2*bits) + 10; /* round up to the next integer */
 391                 break;
 392         case ZD_CCK_RATE_11M:
 393                 if (service) {
 394                         u32 t = bits % 11;
 395                         *service &= ~ZD_PLCP_SERVICE_LENGTH_EXTENSION;
 396                         if (0 < t && t <= 3) {
 397                                 *service |= ZD_PLCP_SERVICE_LENGTH_EXTENSION;
 398                         }
 399                 }
 400                 bits += 10; /* round up to the next integer */
 401                 break;
 402         }
 403
 404         return bits/divisor;
 405 }
 406
 407 static void cs_set_control(struct zd_mac *mac, struct zd_ctrlset *cs,
 408                            struct ieee80211_hdr *header,
 409                            struct ieee80211_tx_info *info)
 410 {
 411         /*
 412          * CONTROL TODO:
 413          * - if backoff needed, enable bit 0
 414          * - if burst (backoff not needed) disable bit 0
 415          */
 416
 417         cs->control = 0;
 418
 419         /* First fragment */
 420         if (info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)
 421                 cs->control |= ZD_CS_NEED_RANDOM_BACKOFF;
 422
 423         /* Multicast */
 424         if (is_multicast_ether_addr(header->addr1))
 425                 cs->control |= ZD_CS_MULTICAST;
 426
 427         /* PS-POLL */
 428         if (ieee80211_is_pspoll(header->frame_control))
 429                 cs->control |= ZD_CS_PS_POLL_FRAME;
 430
 431         if (info->control.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
 432                 cs->control |= ZD_CS_RTS;
 433
 434         if (info->control.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)
 435                 cs->control |= ZD_CS_SELF_CTS;
 436
 437         /* FIXME: Management frame? */
 438 }
 439
 440 static int zd_mac_config_beacon(struct ieee80211_hw *hw, struct sk_buff *beacon)
 441 {
 442         struct zd_mac *mac = zd_hw_mac(hw);
 443         int r;
 444         u32 tmp, j = 0;
 445         /* 4 more bytes for tail CRC */
 446         u32 full_len = beacon->len + 4;
 447
 448         r = zd_iowrite32(&mac->chip, CR_BCN_FIFO_SEMAPHORE, 0);
 449         if (r < 0)
 450                 return r;
 451         r = zd_ioread32(&mac->chip, CR_BCN_FIFO_SEMAPHORE, &tmp);
 452         if (r < 0)
 453                 return r;
 454
 455         while (tmp & 0x2) {
 456                 r = zd_ioread32(&mac->chip, CR_BCN_FIFO_SEMAPHORE, &tmp);
 457                 if (r < 0)
 458                         return r;
 459                 if ((++j % 100) == 0) {
 460                         printk(KERN_ERR "CR_BCN_FIFO_SEMAPHORE not ready\n");
 461                         if (j >= 500)  {
 462                                 printk(KERN_ERR "Giving up beacon config.\n");
 463                                 return -ETIMEDOUT;
 464                         }
 465                 }
 466                 msleep(1);
 467         }
 468
 469         r = zd_iowrite32(&mac->chip, CR_BCN_FIFO, full_len - 1);
 470         if (r < 0)
 471                 return r;
 472         if (zd_chip_is_zd1211b(&mac->chip)) {
 473                 r = zd_iowrite32(&mac->chip, CR_BCN_LENGTH, full_len - 1);
 474                 if (r < 0)
 475                         return r;
 476         }
 477
 478         for (j = 0 ; j < beacon->len; j++) {
 479                 r = zd_iowrite32(&mac->chip, CR_BCN_FIFO,
 480                                 *((u8 *)(beacon->data + j)));
 481                 if (r < 0)
 482                         return r;
 483         }
 484
 485         for (j = 0; j < 4; j++) {
 486                 r = zd_iowrite32(&mac->chip, CR_BCN_FIFO, 0x0);
 487                 if (r < 0)
 488                         return r;
 489         }
 490
 491         r = zd_iowrite32(&mac->chip, CR_BCN_FIFO_SEMAPHORE, 1);
 492         if (r < 0)
 493                 return r;
 494
 495         /* 802.11b/g 2.4G CCK 1Mb
 496          * 802.11a, not yet implemented, uses different values (see GPL vendor
 497          * driver)
 498          */
 499         return zd_iowrite32(&mac->chip, CR_BCN_PLCP_CFG, 0x00000400 |
 500                         (full_len << 19));
 501 }
 502
 503 static int fill_ctrlset(struct zd_mac *mac,
 504                         struct sk_buff *skb)
 505 {
 506         int r;
 507         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 508         unsigned int frag_len = skb->len + FCS_LEN;
 509         unsigned int packet_length;
 510         struct ieee80211_rate *txrate;
 511         struct zd_ctrlset *cs = (struct zd_ctrlset *)
 512                 skb_push(skb, sizeof(struct zd_ctrlset));
 513         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 514
 515         ZD_ASSERT(frag_len <= 0xffff);
 516
 517         txrate = ieee80211_get_tx_rate(mac->hw, info);
 518
 519         cs->modulation = txrate->hw_value;
 520         if (info->control.rates[0].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
 521                 cs->modulation = txrate->hw_value_short;
 522
 523         cs->tx_length = cpu_to_le16(frag_len);
 524
 525         cs_set_control(mac, cs, hdr, info);
 526
 527         packet_length = frag_len + sizeof(struct zd_ctrlset) + 10;
 528         ZD_ASSERT(packet_length <= 0xffff);
 529         /* ZD1211B: Computing the length difference this way, gives us
 530          * flexibility to compute the packet length.
 531          */
 532         cs->packet_length = cpu_to_le16(zd_chip_is_zd1211b(&mac->chip) ?
 533                         packet_length - frag_len : packet_length);
 534
 535         /*
 536          * CURRENT LENGTH:
 537          * - transmit frame length in microseconds
 538          * - seems to be derived from frame length
 539          * - see Cal_Us_Service() in zdinlinef.h
 540          * - if macp->bTxBurstEnable is enabled, then multiply by 4
 541          *  - bTxBurstEnable is never set in the vendor driver
 542          *
 543          * SERVICE:
 544          * - "for PLCP configuration"
 545          * - always 0 except in some situations at 802.11b 11M
 546          * - see line 53 of zdinlinef.h
 547          */
 548         cs->service = 0;
 549         r = zd_calc_tx_length_us(&cs->service, ZD_RATE(cs->modulation),
 550                                  le16_to_cpu(cs->tx_length));
 551         if (r < 0)
 552                 return r;
 553         cs->current_length = cpu_to_le16(r);
 554         cs->next_frame_length = 0;
 555
 556         return 0;
 557 }
 558
 559 /**
 560  * zd_op_tx - transmits a network frame to the device
 561  *
 562  * @dev: mac80211 hardware device
 563  * @skb: socket buffer
 564  * @control: the control structure
 565  *
 566  * This function transmit an IEEE 802.11 network frame to the device. The
 567  * control block of the skbuff will be initialized. If necessary the incoming
 568  * mac80211 queues will be stopped.
 569  */
 570 static int zd_op_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 571 {
 572         struct zd_mac *mac = zd_hw_mac(hw);
 573         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 574         int r;
 575
 576         r = fill_ctrlset(mac, skb);
 577         if (r)
 578                 return r;
 579
 580         info->rate_driver_data[0] = hw;
 581
 582         r = zd_usb_tx(&mac->chip.usb, skb);
 583         if (r)
 584                 return r;
 585         return 0;
 586 }
 587
 588 /**
 589  * filter_ack - filters incoming packets for acknowledgements
 590  * @dev: the mac80211 device
 591  * @rx_hdr: received header
 592  * @stats: the status for the received packet
 593  *
 594  * This functions looks for ACK packets and tries to match them with the
 595  * frames in the tx queue. If a match is found the frame will be dequeued and
 596  * the upper layers is informed about the successful transmission. If
 597  * mac80211 queues have been stopped and the number of frames still to be
 598  * transmitted is low the queues will be opened again.
 599  *
 600  * Returns 1 if the frame was an ACK, 0 if it was ignored.
 601  */
 602 static int filter_ack(struct ieee80211_hw *hw, struct ieee80211_hdr *rx_hdr,
 603                       struct ieee80211_rx_status *stats)
 604 {
 605         struct sk_buff *skb;
 606         struct sk_buff_head *q;
 607         unsigned long flags;
 608
 609         if (!ieee80211_is_ack(rx_hdr->frame_control))
 610                 return 0;
 611
 612         q = &zd_hw_mac(hw)->ack_wait_queue;
 613         spin_lock_irqsave(&q->lock, flags);
 614         skb_queue_walk(q, skb) {
 615                 struct ieee80211_hdr *tx_hdr;
 616
 617                 tx_hdr = (struct ieee80211_hdr *)skb->data;
 618                 if (likely(!memcmp(tx_hdr->addr2, rx_hdr->addr1, ETH_ALEN)))
 619                 {
 620                         __skb_unlink(skb, q);
 621                         tx_status(hw, skb, stats->signal, 1);
 622                         goto out;
 623                 }
 624         }
 625 out:
 626         spin_unlock_irqrestore(&q->lock, flags);
 627         return 1;
 628 }
 629
 630 int zd_mac_rx(struct ieee80211_hw *hw, const u8 *buffer, unsigned int length)
 631 {
 632         struct zd_mac *mac = zd_hw_mac(hw);
 633         struct ieee80211_rx_status stats;
 634         const struct rx_status *status;
 635         struct sk_buff *skb;
 636         int bad_frame = 0;
 637         __le16 fc;
 638         int need_padding;
 639         int i;
 640         u8 rate;
 641
 642         if (length < ZD_PLCP_HEADER_SIZE + 10 /* IEEE80211_1ADDR_LEN */ +
 643                      FCS_LEN + sizeof(struct rx_status))
 644                 return -EINVAL;
 645
 646         memset(&stats, 0, sizeof(stats));
 647
 648         /* Note about pass_failed_fcs and pass_ctrl access below:
 649          * mac locking intentionally omitted here, as this is the only unlocked
 650          * reader and the only writer is configure_filter. Plus, if there were
 651          * any races accessing these variables, it wouldn't really matter.
 652          * If mac80211 ever provides a way for us to access filter flags
 653          * from outside configure_filter, we could improve on this. Also, this
 654          * situation may change once we implement some kind of DMA-into-skb
 655          * RX path. */
 656
 657         /* Caller has to ensure that length >= sizeof(struct rx_status). */
 658         status = (struct rx_status *)
 659                 (buffer + (length - sizeof(struct rx_status)));
 660         if (status->frame_status & ZD_RX_ERROR) {
 661                 if (mac->pass_failed_fcs &&
 662                                 (status->frame_status & ZD_RX_CRC32_ERROR)) {
 663                         stats.flag |= RX_FLAG_FAILED_FCS_CRC;
 664                         bad_frame = 1;
 665                 } else {
 666                         return -EINVAL;
 667                 }
 668         }
 669
 670         stats.freq = zd_channels[_zd_chip_get_channel(&mac->chip) - 1].center_freq;
 671         stats.band = IEEE80211_BAND_2GHZ;
 672         stats.signal = status->signal_strength;
 673         stats.qual = zd_rx_qual_percent(buffer,
 674                                           length - sizeof(struct rx_status),
 675                                           status);
 676
 677         rate = zd_rx_rate(buffer, status);
 678
 679         /* todo: return index in the big switches in zd_rx_rate instead */
 680         for (i = 0; i < mac->band.n_bitrates; i++)
 681                 if (rate == mac->band.bitrates[i].hw_value)
 682                         stats.rate_idx = i;
 683
 684         length -= ZD_PLCP_HEADER_SIZE + sizeof(struct rx_status);
 685         buffer += ZD_PLCP_HEADER_SIZE;
 686
 687         /* Except for bad frames, filter each frame to see if it is an ACK, in
 688          * which case our internal TX tracking is updated. Normally we then
 689          * bail here as there's no need to pass ACKs on up to the stack, but
 690          * there is also the case where the stack has requested us to pass
 691          * control frames on up (pass_ctrl) which we must consider. */
 692         if (!bad_frame &&
 693                         filter_ack(hw, (struct ieee80211_hdr *)buffer, &stats)
 694                         && !mac->pass_ctrl)
 695                 return 0;
 696
 697         fc = *(__le16 *)buffer;
 698         need_padding = ieee80211_is_data_qos(fc) ^ ieee80211_has_a4(fc);
 699
 700         skb = dev_alloc_skb(length + (need_padding ? 2 : 0));
 701         if (skb == NULL)
 702                 return -ENOMEM;
 703         if (need_padding) {
 704                 /* Make sure the the payload data is 4 byte aligned. */
 705                 skb_reserve(skb, 2);
 706         }
 707
 708         memcpy(skb_put(skb, length), buffer, length);
 709
 710         ieee80211_rx_irqsafe(hw, skb, &stats);
 711         return 0;
 712 }
 713
 714 static int zd_op_add_interface(struct ieee80211_hw *hw,
 715                                 struct ieee80211_if_init_conf *conf)
 716 {
 717         struct zd_mac *mac = zd_hw_mac(hw);
 718
 719         /* using NL80211_IFTYPE_UNSPECIFIED to indicate no mode selected */
 720         if (mac->type != NL80211_IFTYPE_UNSPECIFIED)
 721                 return -EOPNOTSUPP;
 722
 723         switch (conf->type) {
 724         case NL80211_IFTYPE_MONITOR:
 725         case NL80211_IFTYPE_MESH_POINT:
 726         case NL80211_IFTYPE_STATION:
 727         case NL80211_IFTYPE_ADHOC:
 728                 mac->type = conf->type;
 729                 break;
 730         default:
 731                 return -EOPNOTSUPP;
 732         }
 733
 734         return zd_write_mac_addr(&mac->chip, conf->mac_addr);
 735 }
 736
 737 static void zd_op_remove_interface(struct ieee80211_hw *hw,
 738                                     struct ieee80211_if_init_conf *conf)
 739 {
 740         struct zd_mac *mac = zd_hw_mac(hw);
 741         mac->type = NL80211_IFTYPE_UNSPECIFIED;
 742         zd_set_beacon_interval(&mac->chip, 0);
 743         zd_write_mac_addr(&mac->chip, NULL);
 744 }
 745
 746 static int zd_op_config(struct ieee80211_hw *hw, u32 changed)
 747 {
 748         struct zd_mac *mac = zd_hw_mac(hw);
 749         struct ieee80211_conf *conf = &hw->conf;
 750
 751         return zd_chip_set_channel(&mac->chip, conf->channel->hw_value);
 752 }
 753
 754 static int zd_op_config_interface(struct ieee80211_hw *hw,
 755                                   struct ieee80211_vif *vif,
 756                                    struct ieee80211_if_conf *conf)
 757 {
 758         struct zd_mac *mac = zd_hw_mac(hw);
 759         int associated;
 760         int r;
 761
 762         if (mac->type == NL80211_IFTYPE_MESH_POINT ||
 763             mac->type == NL80211_IFTYPE_ADHOC) {
 764                 associated = true;
 765                 if (conf->changed & IEEE80211_IFCC_BEACON) {
 766                         struct sk_buff *beacon = ieee80211_beacon_get(hw, vif);
 767
 768                         if (!beacon)
 769                                 return -ENOMEM;
 770                         r = zd_mac_config_beacon(hw, beacon);
 771                         if (r < 0)
 772                                 return r;
 773                         r = zd_set_beacon_interval(&mac->chip, BCN_MODE_IBSS |
 774                                         hw->conf.beacon_int);
 775                         if (r < 0)
 776                                 return r;
 777                         kfree_skb(beacon);
 778                 }
 779         } else
 780                 associated = is_valid_ether_addr(conf->bssid);
 781
 782         spin_lock_irq(&mac->lock);
 783         mac->associated = associated;
 784         spin_unlock_irq(&mac->lock);
 785
 786         /* TODO: do hardware bssid filtering */
 787         return 0;
 788 }
 789
 790 static void zd_process_intr(struct work_struct *work)
 791 {
 792         u16 int_status;
 793         struct zd_mac *mac = container_of(work, struct zd_mac, process_intr);
 794
 795         int_status = le16_to_cpu(*(__le16 *)(mac->intr_buffer+4));
 796         if (int_status & INT_CFG_NEXT_BCN) {
 797                 if (net_ratelimit())
 798                         dev_dbg_f(zd_mac_dev(mac), "INT_CFG_NEXT_BCN\n");
 799         } else
 800                 dev_dbg_f(zd_mac_dev(mac), "Unsupported interrupt\n");
 801
 802         zd_chip_enable_hwint(&mac->chip);
 803 }
 804
 805
 806 static void set_multicast_hash_handler(struct work_struct *work)
 807 {
 808         struct zd_mac *mac =
 809                 container_of(work, struct zd_mac, set_multicast_hash_work);
 810         struct zd_mc_hash hash;
 811
 812         spin_lock_irq(&mac->lock);
 813         hash = mac->multicast_hash;
 814         spin_unlock_irq(&mac->lock);
 815
 816         zd_chip_set_multicast_hash(&mac->chip, &hash);
 817 }
 818
 819 static void set_rx_filter_handler(struct work_struct *work)
 820 {
 821         struct zd_mac *mac =
 822                 container_of(work, struct zd_mac, set_rx_filter_work);
 823         int r;
 824
 825         dev_dbg_f(zd_mac_dev(mac), "\n");
 826         r = set_rx_filter(mac);
 827         if (r)
 828                 dev_err(zd_mac_dev(mac), "set_rx_filter_handler error %d\n", r);
 829 }
 830
 831 #define SUPPORTED_FIF_FLAGS \
 832         (FIF_PROMISC_IN_BSS | FIF_ALLMULTI | FIF_FCSFAIL | FIF_CONTROL | \
 833         FIF_OTHER_BSS | FIF_BCN_PRBRESP_PROMISC)
 834 static void zd_op_configure_filter(struct ieee80211_hw *hw,
 835                         unsigned int changed_flags,
 836                         unsigned int *new_flags,
 837                         int mc_count, struct dev_mc_list *mclist)
 838 {
 839         struct zd_mc_hash hash;
 840         struct zd_mac *mac = zd_hw_mac(hw);
 841         unsigned long flags;
 842         int i;
 843
 844         /* Only deal with supported flags */
 845         changed_flags &= SUPPORTED_FIF_FLAGS;
 846         *new_flags &= SUPPORTED_FIF_FLAGS;
 847
 848         /* changed_flags is always populated but this driver
 849          * doesn't support all FIF flags so its possible we don't
 850          * need to do anything */
 851         if (!changed_flags)
 852                 return;
 853
 854         if (*new_flags & (FIF_PROMISC_IN_BSS | FIF_ALLMULTI)) {
 855                 zd_mc_add_all(&hash);
 856         } else {
 857                 zd_mc_clear(&hash);
 858                 for (i = 0; i < mc_count; i++) {
 859                         if (!mclist)
 860                                 break;
 861                         dev_dbg_f(zd_mac_dev(mac), "mc addr %pM\n",
 862                                   mclist->dmi_addr);
 863                         zd_mc_add_addr(&hash, mclist->dmi_addr);
 864                         mclist = mclist->next;
 865                 }
 866         }
 867
 868         spin_lock_irqsave(&mac->lock, flags);
 869         mac->pass_failed_fcs = !!(*new_flags & FIF_FCSFAIL);
 870         mac->pass_ctrl = !!(*new_flags & FIF_CONTROL);
 871         mac->multicast_hash = hash;
 872         spin_unlock_irqrestore(&mac->lock, flags);
 873         queue_work(zd_workqueue, &mac->set_multicast_hash_work);
 874
 875         if (changed_flags & FIF_CONTROL)
 876                 queue_work(zd_workqueue, &mac->set_rx_filter_work);
 877
 878         /* no handling required for FIF_OTHER_BSS as we don't currently
 879          * do BSSID filtering */
 880         /* FIXME: in future it would be nice to enable the probe response
 881          * filter (so that the driver doesn't see them) until
 882          * FIF_BCN_PRBRESP_PROMISC is set. however due to atomicity here, we'd
 883          * have to schedule work to enable prbresp reception, which might
 884          * happen too late. For now we'll just listen and forward them all the
 885          * time. */
 886 }
 887
 888 static void set_rts_cts_work(struct work_struct *work)
 889 {
 890         struct zd_mac *mac =
 891                 container_of(work, struct zd_mac, set_rts_cts_work);
 892         unsigned long flags;
 893         unsigned int short_preamble;
 894
 895         mutex_lock(&mac->chip.mutex);
 896
 897         spin_lock_irqsave(&mac->lock, flags);
 898         mac->updating_rts_rate = 0;
 899         short_preamble = mac->short_preamble;
 900         spin_unlock_irqrestore(&mac->lock, flags);
 901
 902         zd_chip_set_rts_cts_rate_locked(&mac->chip, short_preamble);
 903         mutex_unlock(&mac->chip.mutex);
 904 }
 905
 906 static void zd_op_bss_info_changed(struct ieee80211_hw *hw,
 907                                    struct ieee80211_vif *vif,
 908                                    struct ieee80211_bss_conf *bss_conf,
 909                                    u32 changes)
 910 {
 911         struct zd_mac *mac = zd_hw_mac(hw);
 912         unsigned long flags;
 913
 914         dev_dbg_f(zd_mac_dev(mac), "changes: %x\n", changes);
 915
 916         if (changes & BSS_CHANGED_ERP_PREAMBLE) {
 917                 spin_lock_irqsave(&mac->lock, flags);
 918                 mac->short_preamble = bss_conf->use_short_preamble;
 919                 if (!mac->updating_rts_rate) {
 920                         mac->updating_rts_rate = 1;
 921                         /* FIXME: should disable TX here, until work has
 922                          * completed and RTS_CTS reg is updated */
 923                         queue_work(zd_workqueue, &mac->set_rts_cts_work);
 924                 }
 925                 spin_unlock_irqrestore(&mac->lock, flags);
 926         }
 927 }
 928
 929 static const struct ieee80211_ops zd_ops = {
 930         .tx                     = zd_op_tx,
 931         .start                  = zd_op_start,
 932         .stop                   = zd_op_stop,
 933         .add_interface          = zd_op_add_interface,
 934         .remove_interface       = zd_op_remove_interface,
 935         .config                 = zd_op_config,
 936         .config_interface       = zd_op_config_interface,
 937         .configure_filter       = zd_op_configure_filter,
 938         .bss_info_changed       = zd_op_bss_info_changed,
 939 };
 940
 941 struct ieee80211_hw *zd_mac_alloc_hw(struct usb_interface *intf)
 942 {
 943         struct zd_mac *mac;
 944         struct ieee80211_hw *hw;
 945
 946         hw = ieee80211_alloc_hw(sizeof(struct zd_mac), &zd_ops);
 947         if (!hw) {
 948                 dev_dbg_f(&intf->dev, "out of memory\n");
 949                 return NULL;
 950         }
 951
 952         mac = zd_hw_mac(hw);
 953
 954         memset(mac, 0, sizeof(*mac));
 955         spin_lock_init(&mac->lock);
 956         mac->hw = hw;
 957
 958         mac->type = NL80211_IFTYPE_UNSPECIFIED;
 959
 960         memcpy(mac->channels, zd_channels, sizeof(zd_channels));
 961         memcpy(mac->rates, zd_rates, sizeof(zd_rates));
 962         mac->band.n_bitrates = ARRAY_SIZE(zd_rates);
 963         mac->band.bitrates = mac->rates;
 964         mac->band.n_channels = ARRAY_SIZE(zd_channels);
 965         mac->band.channels = mac->channels;
 966
 967         hw->wiphy->bands[IEEE80211_BAND_2GHZ] = &mac->band;
 968
 969         hw->flags = IEEE80211_HW_RX_INCLUDES_FCS |
 970                     IEEE80211_HW_SIGNAL_DB;
 971
 972         hw->wiphy->interface_modes =
 973                 BIT(NL80211_IFTYPE_MESH_POINT) |
 974                 BIT(NL80211_IFTYPE_STATION) |
 975                 BIT(NL80211_IFTYPE_ADHOC);
 976
 977         hw->max_signal = 100;
 978         hw->queues = 1;
 979         hw->extra_tx_headroom = sizeof(struct zd_ctrlset);
 980
 981         skb_queue_head_init(&mac->ack_wait_queue);
 982
 983         zd_chip_init(&mac->chip, hw, intf);
 984         housekeeping_init(mac);
 985         INIT_WORK(&mac->set_multicast_hash_work, set_multicast_hash_handler);
 986         INIT_WORK(&mac->set_rts_cts_work, set_rts_cts_work);
 987         INIT_WORK(&mac->set_rx_filter_work, set_rx_filter_handler);
 988         INIT_WORK(&mac->process_intr, zd_process_intr);
 989
 990         SET_IEEE80211_DEV(hw, &intf->dev);
 991         return hw;
 992 }
 993
 994 #define LINK_LED_WORK_DELAY HZ
 995
 996 static void link_led_handler(struct work_struct *work)
 997 {
 998         struct zd_mac *mac =
 999                 container_of(work, struct zd_mac, housekeeping.link_led_work.work);
1000         struct zd_chip *chip = &mac->chip;
1001         int is_associated;
1002         int r;
1003
1004         spin_lock_irq(&mac->lock);
1005         is_associated = mac->associated;
1006         spin_unlock_irq(&mac->lock);
1007
1008         r = zd_chip_control_leds(chip,
1009                                  is_associated ? LED_ASSOCIATED : LED_SCANNING);
1010         if (r)
1011                 dev_dbg_f(zd_mac_dev(mac), "zd_chip_control_leds error %d\n", r);
1012
1013         queue_delayed_work(zd_workqueue, &mac->housekeeping.link_led_work,
1014                            LINK_LED_WORK_DELAY);
1015 }
1016
1017 static void housekeeping_init(struct zd_mac *mac)
1018 {
1019         INIT_DELAYED_WORK(&mac->housekeeping.link_led_work, link_led_handler);
1020 }
1021
1022 static void housekeeping_enable(struct zd_mac *mac)
1023 {
1024         dev_dbg_f(zd_mac_dev(mac), "\n");
1025         queue_delayed_work(zd_workqueue, &mac->housekeeping.link_led_work,
1026                            0);
1027 }
1028
1029 static void housekeeping_disable(struct zd_mac *mac)
1030 {
1031         dev_dbg_f(zd_mac_dev(mac), "\n");
1032         cancel_rearming_delayed_workqueue(zd_workqueue,
1033                 &mac->housekeeping.link_led_work);
1034         zd_chip_control_leds(&mac->chip, LED_OFF);
1035 }