drivers/net/wireless/iwlwifi/iwl-tx.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2003 - 2011 Intel Corporation. All rights reserved.
   4  *
   5  * Portions of this file are derived from the ipw3945 project, as well
   6  * as portions of the ieee80211 subsystem header files.
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of version 2 of the GNU General Public License as
  10  * published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15  * more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along with
  18  * this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  20  *
  21  * The full GNU General Public License is included in this distribution in the
  22  * file called LICENSE.
  23  *
  24  * Contact Information:
  25  *  Intel Linux Wireless <ilw@linux.intel.com>
  26  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  27  *
  28  *****************************************************************************/
  29
  30 #include <linux/etherdevice.h>
  31 #include <linux/sched.h>
  32 #include <linux/slab.h>
  33 #include <net/mac80211.h>
  34 #include "iwl-eeprom.h"
  35 #include "iwl-agn.h"
  36 #include "iwl-dev.h"
  37 #include "iwl-core.h"
  38 #include "iwl-sta.h"
  39 #include "iwl-io.h"
  40 #include "iwl-helpers.h"
  41
  42 /**
  43  * iwl_txq_update_write_ptr - Send new write index to hardware
  44  */
  45 void iwl_txq_update_write_ptr(struct iwl_priv *priv, struct iwl_tx_queue *txq)
  46 {
  47         u32 reg = 0;
  48         int txq_id = txq->q.id;
  49
  50         if (txq->need_update == 0)
  51                 return;
  52
  53         if (priv->cfg->base_params->shadow_reg_enable) {
  54                 /* shadow register enabled */
  55                 iwl_write32(priv, HBUS_TARG_WRPTR,
  56                             txq->q.write_ptr | (txq_id << 8));
  57         } else {
  58                 /* if we're trying to save power */
  59                 if (test_bit(STATUS_POWER_PMI, &priv->status)) {
  60                         /* wake up nic if it's powered down ...
  61                          * uCode will wake up, and interrupt us again, so next
  62                          * time we'll skip this part. */
  63                         reg = iwl_read32(priv, CSR_UCODE_DRV_GP1);
  64
  65                         if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
  66                                 IWL_DEBUG_INFO(priv,
  67                                         "Tx queue %d requesting wakeup,"
  68                                         " GP1 = 0x%x\n", txq_id, reg);
  69                                 iwl_set_bit(priv, CSR_GP_CNTRL,
  70                                         CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
  71                                 return;
  72                         }
  73
  74                         iwl_write_direct32(priv, HBUS_TARG_WRPTR,
  75                                      txq->q.write_ptr | (txq_id << 8));
  76
  77                 /*
  78                  * else not in power-save mode,
  79                  * uCode will never sleep when we're
  80                  * trying to tx (during RFKILL, we're not trying to tx).
  81                  */
  82                 } else
  83                         iwl_write32(priv, HBUS_TARG_WRPTR,
  84                                     txq->q.write_ptr | (txq_id << 8));
  85         }
  86         txq->need_update = 0;
  87 }
  88
  89 static inline dma_addr_t iwl_tfd_tb_get_addr(struct iwl_tfd *tfd, u8 idx)
  90 {
  91         struct iwl_tfd_tb *tb = &tfd->tbs[idx];
  92
  93         dma_addr_t addr = get_unaligned_le32(&tb->lo);
  94         if (sizeof(dma_addr_t) > sizeof(u32))
  95                 addr |=
  96                 ((dma_addr_t)(le16_to_cpu(tb->hi_n_len) & 0xF) << 16) << 16;
  97
  98         return addr;
  99 }
 100
 101 static inline u16 iwl_tfd_tb_get_len(struct iwl_tfd *tfd, u8 idx)
 102 {
 103         struct iwl_tfd_tb *tb = &tfd->tbs[idx];
 104
 105         return le16_to_cpu(tb->hi_n_len) >> 4;
 106 }
 107
 108 static inline void iwl_tfd_set_tb(struct iwl_tfd *tfd, u8 idx,
 109                                   dma_addr_t addr, u16 len)
 110 {
 111         struct iwl_tfd_tb *tb = &tfd->tbs[idx];
 112         u16 hi_n_len = len << 4;
 113
 114         put_unaligned_le32(addr, &tb->lo);
 115         if (sizeof(dma_addr_t) > sizeof(u32))
 116                 hi_n_len |= ((addr >> 16) >> 16) & 0xF;
 117
 118         tb->hi_n_len = cpu_to_le16(hi_n_len);
 119
 120         tfd->num_tbs = idx + 1;
 121 }
 122
 123 static inline u8 iwl_tfd_get_num_tbs(struct iwl_tfd *tfd)
 124 {
 125         return tfd->num_tbs & 0x1f;
 126 }
 127
 128 static void iwlagn_unmap_tfd(struct iwl_priv *priv, struct iwl_cmd_meta *meta,
 129                              struct iwl_tfd *tfd, enum dma_data_direction dma_dir)
 130 {
 131         int i;
 132         int num_tbs;
 133
 134         /* Sanity check on number of chunks */
 135         num_tbs = iwl_tfd_get_num_tbs(tfd);
 136
 137         if (num_tbs >= IWL_NUM_OF_TBS) {
 138                 IWL_ERR(priv, "Too many chunks: %i\n", num_tbs);
 139                 /* @todo issue fatal error, it is quite serious situation */
 140                 return;
 141         }
 142
 143         /* Unmap tx_cmd */
 144         if (num_tbs)
 145                 dma_unmap_single(priv->bus.dev,
 146                                 dma_unmap_addr(meta, mapping),
 147                                 dma_unmap_len(meta, len),
 148                                 DMA_BIDIRECTIONAL);
 149
 150         /* Unmap chunks, if any. */
 151         for (i = 1; i < num_tbs; i++)
 152                 dma_unmap_single(priv->bus.dev, iwl_tfd_tb_get_addr(tfd, i),
 153                                 iwl_tfd_tb_get_len(tfd, i), dma_dir);
 154 }
 155
 156 /**
 157  * iwlagn_txq_free_tfd - Free all chunks referenced by TFD [txq->q.read_ptr]
 158  * @priv - driver private data
 159  * @txq - tx queue
 160  * @index - the index of the TFD to be freed
 161  *
 162  * Does NOT advance any TFD circular buffer read/write indexes
 163  * Does NOT free the TFD itself (which is within circular buffer)
 164  */
 165 void iwlagn_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq,
 166         int index)
 167 {
 168         struct iwl_tfd *tfd_tmp = txq->tfds;
 169
 170         iwlagn_unmap_tfd(priv, &txq->meta[index], &tfd_tmp[index],
 171                          DMA_TO_DEVICE);
 172
 173         /* free SKB */
 174         if (txq->txb) {
 175                 struct sk_buff *skb;
 176
 177                 skb = txq->txb[index].skb;
 178
 179                 /* can be called from irqs-disabled context */
 180                 if (skb) {
 181                         dev_kfree_skb_any(skb);
 182                         txq->txb[index].skb = NULL;
 183                 }
 184         }
 185 }
 186
 187 int iwlagn_txq_attach_buf_to_tfd(struct iwl_priv *priv,
 188                                  struct iwl_tx_queue *txq,
 189                                  dma_addr_t addr, u16 len,
 190                                  u8 reset)
 191 {
 192         struct iwl_queue *q;
 193         struct iwl_tfd *tfd, *tfd_tmp;
 194         u32 num_tbs;
 195
 196         q = &txq->q;
 197         tfd_tmp = txq->tfds;
 198         tfd = &tfd_tmp[q->write_ptr];
 199
 200         if (reset)
 201                 memset(tfd, 0, sizeof(*tfd));
 202
 203         num_tbs = iwl_tfd_get_num_tbs(tfd);
 204
 205         /* Each TFD can point to a maximum 20 Tx buffers */
 206         if (num_tbs >= IWL_NUM_OF_TBS) {
 207                 IWL_ERR(priv, "Error can not send more than %d chunks\n",
 208                           IWL_NUM_OF_TBS);
 209                 return -EINVAL;
 210         }
 211
 212         if (WARN_ON(addr & ~DMA_BIT_MASK(36)))
 213                 return -EINVAL;
 214
 215         if (unlikely(addr & ~IWL_TX_DMA_MASK))
 216                 IWL_ERR(priv, "Unaligned address = %llx\n",
 217                           (unsigned long long)addr);
 218
 219         iwl_tfd_set_tb(tfd, num_tbs, addr, len);
 220
 221         return 0;
 222 }
 223
 224 /*************** DMA-QUEUE-GENERAL-FUNCTIONS  *****
 225  * DMA services
 226  *
 227  * Theory of operation
 228  *
 229  * A Tx or Rx queue resides in host DRAM, and is comprised of a circular buffer
 230  * of buffer descriptors, each of which points to one or more data buffers for
 231  * the device to read from or fill.  Driver and device exchange status of each
 232  * queue via "read" and "write" pointers.  Driver keeps minimum of 2 empty
 233  * entries in each circular buffer, to protect against confusing empty and full
 234  * queue states.
 235  *
 236  * The device reads or writes the data in the queues via the device's several
 237  * DMA/FIFO channels.  Each queue is mapped to a single DMA channel.
 238  *
 239  * For Tx queue, there are low mark and high mark limits. If, after queuing
 240  * the packet for Tx, free space become < low mark, Tx queue stopped. When
 241  * reclaiming packets (on 'tx done IRQ), if free space become > high mark,
 242  * Tx queue resumed.
 243  *
 244  ***************************************************/
 245
 246 int iwl_queue_space(const struct iwl_queue *q)
 247 {
 248         int s = q->read_ptr - q->write_ptr;
 249
 250         if (q->read_ptr > q->write_ptr)
 251                 s -= q->n_bd;
 252
 253         if (s <= 0)
 254                 s += q->n_window;
 255         /* keep some reserve to not confuse empty and full situations */
 256         s -= 2;
 257         if (s < 0)
 258                 s = 0;
 259         return s;
 260 }
 261
 262 /**
 263  * iwl_queue_init - Initialize queue's high/low-water and read/write indexes
 264  */
 265 int iwl_queue_init(struct iwl_priv *priv, struct iwl_queue *q,
 266                           int count, int slots_num, u32 id)
 267 {
 268         q->n_bd = count;
 269         q->n_window = slots_num;
 270         q->id = id;
 271
 272         /* count must be power-of-two size, otherwise iwl_queue_inc_wrap
 273          * and iwl_queue_dec_wrap are broken. */
 274         if (WARN_ON(!is_power_of_2(count)))
 275                 return -EINVAL;
 276
 277         /* slots_num must be power-of-two size, otherwise
 278          * get_cmd_index is broken. */
 279         if (WARN_ON(!is_power_of_2(slots_num)))
 280                 return -EINVAL;
 281
 282         q->low_mark = q->n_window / 4;
 283         if (q->low_mark < 4)
 284                 q->low_mark = 4;
 285
 286         q->high_mark = q->n_window / 8;
 287         if (q->high_mark < 2)
 288                 q->high_mark = 2;
 289
 290         q->write_ptr = q->read_ptr = 0;
 291
 292         return 0;
 293 }
 294
 295 /*************** HOST COMMAND QUEUE FUNCTIONS   *****/
 296
 297 /**
 298  * iwl_enqueue_hcmd - enqueue a uCode command
 299  * @priv: device private data point
 300  * @cmd: a point to the ucode command structure
 301  *
 302  * The function returns < 0 values to indicate the operation is
 303  * failed. On success, it turns the index (> 0) of command in the
 304  * command queue.
 305  */
 306 int iwl_enqueue_hcmd(struct iwl_priv *priv, struct iwl_host_cmd *cmd)
 307 {
 308         struct iwl_tx_queue *txq = &priv->txq[priv->cmd_queue];
 309         struct iwl_queue *q = &txq->q;
 310         struct iwl_device_cmd *out_cmd;
 311         struct iwl_cmd_meta *out_meta;
 312         dma_addr_t phys_addr;
 313         unsigned long flags;
 314         u32 idx;
 315         u16 copy_size, cmd_size;
 316         bool is_ct_kill = false;
 317         bool had_nocopy = false;
 318         int i;
 319         u8 *cmd_dest;
 320 #ifdef CONFIG_IWLWIFI_DEVICE_TRACING
 321         const void *trace_bufs[IWL_MAX_CMD_TFDS + 1] = {};
 322         int trace_lens[IWL_MAX_CMD_TFDS + 1] = {};
 323         int trace_idx;
 324 #endif
 325
 326         if (test_bit(STATUS_FW_ERROR, &priv->status)) {
 327                 IWL_WARN(priv, "fw recovery, no hcmd send\n");
 328                 return -EIO;
 329         }
 330
 331         if ((priv->ucode_owner == IWL_OWNERSHIP_TM) &&
 332             !(cmd->flags & CMD_ON_DEMAND)) {
 333                 IWL_DEBUG_HC(priv, "tm own the uCode, no regular hcmd send\n");
 334                 return -EIO;
 335         }
 336
 337         copy_size = sizeof(out_cmd->hdr);
 338         cmd_size = sizeof(out_cmd->hdr);
 339
 340         /* need one for the header if the first is NOCOPY */
 341         BUILD_BUG_ON(IWL_MAX_CMD_TFDS > IWL_NUM_OF_TBS - 1);
 342
 343         for (i = 0; i < IWL_MAX_CMD_TFDS; i++) {
 344                 if (!cmd->len[i])
 345                         continue;
 346                 if (cmd->dataflags[i] & IWL_HCMD_DFL_NOCOPY) {
 347                         had_nocopy = true;
 348                 } else {
 349                         /* NOCOPY must not be followed by normal! */
 350                         if (WARN_ON(had_nocopy))
 351                                 return -EINVAL;
 352                         copy_size += cmd->len[i];
 353                 }
 354                 cmd_size += cmd->len[i];
 355         }
 356
 357         /*
 358          * If any of the command structures end up being larger than
 359          * the TFD_MAX_PAYLOAD_SIZE and they aren't dynamically
 360          * allocated into separate TFDs, then we will need to
 361          * increase the size of the buffers.
 362          */
 363         if (WARN_ON(copy_size > TFD_MAX_PAYLOAD_SIZE))
 364                 return -EINVAL;
 365
 366         if (iwl_is_rfkill(priv) || iwl_is_ctkill(priv)) {
 367                 IWL_WARN(priv, "Not sending command - %s KILL\n",
 368                          iwl_is_rfkill(priv) ? "RF" : "CT");
 369                 return -EIO;
 370         }
 371
 372         spin_lock_irqsave(&priv->hcmd_lock, flags);
 373
 374         if (iwl_queue_space(q) < ((cmd->flags & CMD_ASYNC) ? 2 : 1)) {
 375                 spin_unlock_irqrestore(&priv->hcmd_lock, flags);
 376
 377                 IWL_ERR(priv, "No space in command queue\n");
 378                 is_ct_kill = iwl_check_for_ct_kill(priv);
 379                 if (!is_ct_kill) {
 380                         IWL_ERR(priv, "Restarting adapter due to queue full\n");
 381                         iwlagn_fw_error(priv, false);
 382                 }
 383                 return -ENOSPC;
 384         }
 385
 386         idx = get_cmd_index(q, q->write_ptr);
 387         out_cmd = txq->cmd[idx];
 388         out_meta = &txq->meta[idx];
 389
 390         memset(out_meta, 0, sizeof(*out_meta)); /* re-initialize to NULL */
 391         if (cmd->flags & CMD_WANT_SKB)
 392                 out_meta->source = cmd;
 393         if (cmd->flags & CMD_ASYNC)
 394                 out_meta->callback = cmd->callback;
 395
 396         /* set up the header */
 397
 398         out_cmd->hdr.cmd = cmd->id;
 399         out_cmd->hdr.flags = 0;
 400         out_cmd->hdr.sequence = cpu_to_le16(QUEUE_TO_SEQ(priv->cmd_queue) |
 401                                             INDEX_TO_SEQ(q->write_ptr));
 402
 403         /* and copy the data that needs to be copied */
 404
 405         cmd_dest = &out_cmd->cmd.payload[0];
 406         for (i = 0; i < IWL_MAX_CMD_TFDS; i++) {
 407                 if (!cmd->len[i])
 408                         continue;
 409                 if (cmd->dataflags[i] & IWL_HCMD_DFL_NOCOPY)
 410                         break;
 411                 memcpy(cmd_dest, cmd->data[i], cmd->len[i]);
 412                 cmd_dest += cmd->len[i];
 413         }
 414
 415         IWL_DEBUG_HC(priv, "Sending command %s (#%x), seq: 0x%04X, "
 416                         "%d bytes at %d[%d]:%d\n",
 417                         get_cmd_string(out_cmd->hdr.cmd),
 418                         out_cmd->hdr.cmd,
 419                         le16_to_cpu(out_cmd->hdr.sequence), cmd_size,
 420                         q->write_ptr, idx, priv->cmd_queue);
 421
 422         phys_addr = dma_map_single(priv->bus.dev, &out_cmd->hdr, copy_size,
 423                                 DMA_BIDIRECTIONAL);
 424         if (unlikely(dma_mapping_error(priv->bus.dev, phys_addr))) {
 425                 idx = -ENOMEM;
 426                 goto out;
 427         }
 428
 429         dma_unmap_addr_set(out_meta, mapping, phys_addr);
 430         dma_unmap_len_set(out_meta, len, copy_size);
 431
 432         iwlagn_txq_attach_buf_to_tfd(priv, txq, phys_addr, copy_size, 1);
 433 #ifdef CONFIG_IWLWIFI_DEVICE_TRACING
 434         trace_bufs[0] = &out_cmd->hdr;
 435         trace_lens[0] = copy_size;
 436         trace_idx = 1;
 437 #endif
 438
 439         for (i = 0; i < IWL_MAX_CMD_TFDS; i++) {
 440                 if (!cmd->len[i])
 441                         continue;
 442                 if (!(cmd->dataflags[i] & IWL_HCMD_DFL_NOCOPY))
 443                         continue;
 444                 phys_addr = dma_map_single(priv->bus.dev, (void *)cmd->data[i],
 445                                            cmd->len[i], DMA_BIDIRECTIONAL);
 446                 if (dma_mapping_error(priv->bus.dev, phys_addr)) {
 447                         iwlagn_unmap_tfd(priv, out_meta,
 448                                          &txq->tfds[q->write_ptr],
 449                                          DMA_BIDIRECTIONAL);
 450                         idx = -ENOMEM;
 451                         goto out;
 452                 }
 453
 454                 iwlagn_txq_attach_buf_to_tfd(priv, txq, phys_addr,
 455                                              cmd->len[i], 0);
 456 #ifdef CONFIG_IWLWIFI_DEVICE_TRACING
 457                 trace_bufs[trace_idx] = cmd->data[i];
 458                 trace_lens[trace_idx] = cmd->len[i];
 459                 trace_idx++;
 460 #endif
 461         }
 462
 463         out_meta->flags = cmd->flags;
 464
 465         txq->need_update = 1;
 466
 467         /* check that tracing gets all possible blocks */
 468         BUILD_BUG_ON(IWL_MAX_CMD_TFDS + 1 != 3);
 469 #ifdef CONFIG_IWLWIFI_DEVICE_TRACING
 470         trace_iwlwifi_dev_hcmd(priv, cmd->flags,
 471                                trace_bufs[0], trace_lens[0],
 472                                trace_bufs[1], trace_lens[1],
 473                                trace_bufs[2], trace_lens[2]);
 474 #endif
 475
 476         /* Increment and update queue's write index */
 477         q->write_ptr = iwl_queue_inc_wrap(q->write_ptr, q->n_bd);
 478         iwl_txq_update_write_ptr(priv, txq);
 479
 480  out:
 481         spin_unlock_irqrestore(&priv->hcmd_lock, flags);
 482         return idx;
 483 }
 484
 485 /**
 486  * iwl_hcmd_queue_reclaim - Reclaim TX command queue entries already Tx'd
 487  *
 488  * When FW advances 'R' index, all entries between old and new 'R' index
 489  * need to be reclaimed. As result, some free space forms.  If there is
 490  * enough free space (> low mark), wake the stack that feeds us.
 491  */
 492 static void iwl_hcmd_queue_reclaim(struct iwl_priv *priv, int txq_id, int idx)
 493 {
 494         struct iwl_tx_queue *txq = &priv->txq[txq_id];
 495         struct iwl_queue *q = &txq->q;
 496         int nfreed = 0;
 497
 498         if ((idx >= q->n_bd) || (iwl_queue_used(q, idx) == 0)) {
 499                 IWL_ERR(priv, "%s: Read index for DMA queue txq id (%d), "
 500                           "index %d is out of range [0-%d] %d %d.\n", __func__,
 501                           txq_id, idx, q->n_bd, q->write_ptr, q->read_ptr);
 502                 return;
 503         }
 504
 505         for (idx = iwl_queue_inc_wrap(idx, q->n_bd); q->read_ptr != idx;
 506              q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd)) {
 507
 508                 if (nfreed++ > 0) {
 509                         IWL_ERR(priv, "HCMD skipped: index (%d) %d %d\n", idx,
 510                                         q->write_ptr, q->read_ptr);
 511                         iwlagn_fw_error(priv, false);
 512                 }
 513
 514         }
 515 }
 516
 517 /**
 518  * iwl_tx_cmd_complete - Pull unused buffers off the queue and reclaim them
 519  * @rxb: Rx buffer to reclaim
 520  *
 521  * If an Rx buffer has an async callback associated with it the callback
 522  * will be executed.  The attached skb (if present) will only be freed
 523  * if the callback returns 1
 524  */
 525 void iwl_tx_cmd_complete(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb)
 526 {
 527         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 528         u16 sequence = le16_to_cpu(pkt->hdr.sequence);
 529         int txq_id = SEQ_TO_QUEUE(sequence);
 530         int index = SEQ_TO_INDEX(sequence);
 531         int cmd_index;
 532         struct iwl_device_cmd *cmd;
 533         struct iwl_cmd_meta *meta;
 534         struct iwl_tx_queue *txq = &priv->txq[priv->cmd_queue];
 535         unsigned long flags;
 536
 537         /* If a Tx command is being handled and it isn't in the actual
 538          * command queue then there a command routing bug has been introduced
 539          * in the queue management code. */
 540         if (WARN(txq_id != priv->cmd_queue,
 541                  "wrong command queue %d (should be %d), sequence 0x%X readp=%d writep=%d\n",
 542                   txq_id, priv->cmd_queue, sequence,
 543                   priv->txq[priv->cmd_queue].q.read_ptr,
 544                   priv->txq[priv->cmd_queue].q.write_ptr)) {
 545                 iwl_print_hex_error(priv, pkt, 32);
 546                 return;
 547         }
 548
 549         cmd_index = get_cmd_index(&txq->q, index);
 550         cmd = txq->cmd[cmd_index];
 551         meta = &txq->meta[cmd_index];
 552
 553         iwlagn_unmap_tfd(priv, meta, &txq->tfds[index], DMA_BIDIRECTIONAL);
 554
 555         /* Input error checking is done when commands are added to queue. */
 556         if (meta->flags & CMD_WANT_SKB) {
 557                 meta->source->reply_page = (unsigned long)rxb_addr(rxb);
 558                 rxb->page = NULL;
 559         } else if (meta->callback)
 560                 meta->callback(priv, cmd, pkt);
 561
 562         spin_lock_irqsave(&priv->hcmd_lock, flags);
 563
 564         iwl_hcmd_queue_reclaim(priv, txq_id, index);
 565
 566         if (!(meta->flags & CMD_ASYNC)) {
 567                 clear_bit(STATUS_HCMD_ACTIVE, &priv->status);
 568                 IWL_DEBUG_INFO(priv, "Clearing HCMD_ACTIVE for command %s\n",
 569                                get_cmd_string(cmd->hdr.cmd));
 570                 wake_up_interruptible(&priv->wait_command_queue);
 571         }
 572
 573         meta->flags = 0;
 574
 575         spin_unlock_irqrestore(&priv->hcmd_lock, flags);
 576 }