drivers/net/wireless/cw1200/bh.c

   1 /*
   2  * Device handling thread implementation for mac80211 ST-Ericsson CW1200 drivers
   3  *
   4  * Copyright (c) 2010, ST-Ericsson
   5  * Author: Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
   6  *
   7  * Based on:
   8  * ST-Ericsson UMAC CW1200 driver, which is
   9  * Copyright (c) 2010, ST-Ericsson
  10  * Author: Ajitpal Singh <ajitpal.singh@stericsson.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License version 2 as
  14  * published by the Free Software Foundation.
  15  */
  16
  17 #include <linux/module.h>
  18 #include <net/mac80211.h>
  19 #include <linux/kthread.h>
  20 #include <linux/timer.h>
  21
  22 #include "cw1200.h"
  23 #include "bh.h"
  24 #include "hwio.h"
  25 #include "wsm.h"
  26 #include "hwbus.h"
  27 #include "debug.h"
  28 #include "fwio.h"
  29
  30 static int cw1200_bh(void *arg);
  31
  32 #define DOWNLOAD_BLOCK_SIZE_WR  (0x1000 - 4)
  33 /* an SPI message cannot be bigger than (2"12-1)*2 bytes
  34  * "*2" to cvt to bytes
  35  */
  36 #define MAX_SZ_RD_WR_BUFFERS    (DOWNLOAD_BLOCK_SIZE_WR*2)
  37 #define PIGGYBACK_CTRL_REG      (2)
  38 #define EFFECTIVE_BUF_SIZE      (MAX_SZ_RD_WR_BUFFERS - PIGGYBACK_CTRL_REG)
  39
  40 /* Suspend state privates */
  41 enum cw1200_bh_pm_state {
  42         CW1200_BH_RESUMED = 0,
  43         CW1200_BH_SUSPEND,
  44         CW1200_BH_SUSPENDED,
  45         CW1200_BH_RESUME,
  46 };
  47
  48 typedef int (*cw1200_wsm_handler)(struct cw1200_common *priv,
  49         u8 *data, size_t size);
  50
  51 static void cw1200_bh_work(struct work_struct *work)
  52 {
  53         struct cw1200_common *priv =
  54         container_of(work, struct cw1200_common, bh_work);
  55         cw1200_bh(priv);
  56 }
  57
  58 int cw1200_register_bh(struct cw1200_common *priv)
  59 {
  60         int err = 0;
  61         /* Realtime workqueue */
  62         priv->bh_workqueue = alloc_workqueue("cw1200_bh",
  63                                 WQ_MEM_RECLAIM | WQ_HIGHPRI
  64                                 | WQ_CPU_INTENSIVE, 1);
  65
  66         if (!priv->bh_workqueue)
  67                 return -ENOMEM;
  68
  69         INIT_WORK(&priv->bh_work, cw1200_bh_work);
  70
  71         pr_debug("[BH] register.\n");
  72
  73         atomic_set(&priv->bh_rx, 0);
  74         atomic_set(&priv->bh_tx, 0);
  75         atomic_set(&priv->bh_term, 0);
  76         atomic_set(&priv->bh_suspend, CW1200_BH_RESUMED);
  77         priv->bh_error = 0;
  78         priv->hw_bufs_used = 0;
  79         priv->buf_id_tx = 0;
  80         priv->buf_id_rx = 0;
  81         init_waitqueue_head(&priv->bh_wq);
  82         init_waitqueue_head(&priv->bh_evt_wq);
  83
  84         err = !queue_work(priv->bh_workqueue, &priv->bh_work);
  85         WARN_ON(err);
  86         return err;
  87 }
  88
  89 void cw1200_unregister_bh(struct cw1200_common *priv)
  90 {
  91         atomic_add(1, &priv->bh_term);
  92         wake_up(&priv->bh_wq);
  93
  94         flush_workqueue(priv->bh_workqueue);
  95
  96         destroy_workqueue(priv->bh_workqueue);
  97         priv->bh_workqueue = NULL;
  98
  99         pr_debug("[BH] unregistered.\n");
 100 }
 101
 102 void cw1200_irq_handler(struct cw1200_common *priv)
 103 {
 104         pr_debug("[BH] irq.\n");
 105
 106         /* Disable Interrupts! */
 107         /* NOTE:  hwbus_ops->lock already held */
 108         __cw1200_irq_enable(priv, 0);
 109
 110         if (/* WARN_ON */(priv->bh_error))
 111                 return;
 112
 113         if (atomic_add_return(1, &priv->bh_rx) == 1)
 114                 wake_up(&priv->bh_wq);
 115 }
 116 EXPORT_SYMBOL_GPL(cw1200_irq_handler);
 117
 118 void cw1200_bh_wakeup(struct cw1200_common *priv)
 119 {
 120         pr_debug("[BH] wakeup.\n");
 121         if (priv->bh_error) {
 122                 pr_err("[BH] wakeup failed (BH error)\n");
 123                 return;
 124         }
 125
 126         if (atomic_add_return(1, &priv->bh_tx) == 1)
 127                 wake_up(&priv->bh_wq);
 128 }
 129
 130 int cw1200_bh_suspend(struct cw1200_common *priv)
 131 {
 132         pr_debug("[BH] suspend.\n");
 133         if (priv->bh_error) {
 134                 wiphy_warn(priv->hw->wiphy, "BH error -- can't suspend\n");
 135                 return -EINVAL;
 136         }
 137
 138         atomic_set(&priv->bh_suspend, CW1200_BH_SUSPEND);
 139         wake_up(&priv->bh_wq);
 140         return wait_event_timeout(priv->bh_evt_wq, priv->bh_error ||
 141                 (CW1200_BH_SUSPENDED == atomic_read(&priv->bh_suspend)),
 142                  1 * HZ) ? 0 : -ETIMEDOUT;
 143 }
 144
 145 int cw1200_bh_resume(struct cw1200_common *priv)
 146 {
 147         pr_debug("[BH] resume.\n");
 148         if (priv->bh_error) {
 149                 wiphy_warn(priv->hw->wiphy, "BH error -- can't resume\n");
 150                 return -EINVAL;
 151         }
 152
 153         atomic_set(&priv->bh_suspend, CW1200_BH_RESUME);
 154         wake_up(&priv->bh_wq);
 155         return wait_event_timeout(priv->bh_evt_wq, priv->bh_error ||
 156                 (CW1200_BH_RESUMED == atomic_read(&priv->bh_suspend)),
 157                 1 * HZ) ? 0 : -ETIMEDOUT;
 158 }
 159
 160 static inline void wsm_alloc_tx_buffer(struct cw1200_common *priv)
 161 {
 162         ++priv->hw_bufs_used;
 163 }
 164
 165 int wsm_release_tx_buffer(struct cw1200_common *priv, int count)
 166 {
 167         int ret = 0;
 168         int hw_bufs_used = priv->hw_bufs_used;
 169
 170         priv->hw_bufs_used -= count;
 171         if (WARN_ON(priv->hw_bufs_used < 0))
 172                 ret = -1;
 173         else if (hw_bufs_used >= priv->wsm_caps.input_buffers)
 174                 ret = 1;
 175         if (!priv->hw_bufs_used)
 176                 wake_up(&priv->bh_evt_wq);
 177         return ret;
 178 }
 179
 180 static int cw1200_bh_read_ctrl_reg(struct cw1200_common *priv,
 181                                           u16 *ctrl_reg)
 182 {
 183         int ret;
 184
 185         ret = cw1200_reg_read_16(priv,
 186                         ST90TDS_CONTROL_REG_ID, ctrl_reg);
 187         if (ret) {
 188                 ret = cw1200_reg_read_16(priv,
 189                                 ST90TDS_CONTROL_REG_ID, ctrl_reg);
 190                 if (ret)
 191                         pr_err("[BH] Failed to read control register.\n");
 192         }
 193
 194         return ret;
 195 }
 196
 197 static int cw1200_device_wakeup(struct cw1200_common *priv)
 198 {
 199         u16 ctrl_reg;
 200         int ret;
 201
 202         pr_debug("[BH] Device wakeup.\n");
 203
 204         /* First, set the dpll register */
 205         ret = cw1200_reg_write_32(priv, ST90TDS_TSET_GEN_R_W_REG_ID,
 206                                   cw1200_dpll_from_clk(priv->hw_refclk));
 207         if (WARN_ON(ret))
 208                 return ret;
 209
 210         /* To force the device to be always-on, the host sets WLAN_UP to 1 */
 211         ret = cw1200_reg_write_16(priv, ST90TDS_CONTROL_REG_ID,
 212                         ST90TDS_CONT_WUP_BIT);
 213         if (WARN_ON(ret))
 214                 return ret;
 215
 216         ret = cw1200_bh_read_ctrl_reg(priv, &ctrl_reg);
 217         if (WARN_ON(ret))
 218                 return ret;
 219
 220         /* If the device returns WLAN_RDY as 1, the device is active and will
 221          * remain active.
 222          */
 223         if (ctrl_reg & ST90TDS_CONT_RDY_BIT) {
 224                 pr_debug("[BH] Device awake.\n");
 225                 return 1;
 226         }
 227
 228         return 0;
 229 }
 230
 231 /* Must be called from BH thraed. */
 232 void cw1200_enable_powersave(struct cw1200_common *priv,
 233                              bool enable)
 234 {
 235         pr_debug("[BH] Powerave is %s.\n",
 236                  enable ? "enabled" : "disabled");
 237         priv->powersave_enabled = enable;
 238 }
 239
 240 static int cw1200_bh_rx_helper(struct cw1200_common *priv,
 241                                uint16_t *ctrl_reg,
 242                                int *tx)
 243 {
 244         size_t read_len = 0;
 245         struct sk_buff *skb_rx = NULL;
 246         struct wsm_hdr *wsm;
 247         size_t wsm_len;
 248         u16 wsm_id;
 249         u8 wsm_seq;
 250         int rx_resync = 1;
 251
 252         size_t alloc_len;
 253         u8 *data;
 254
 255         read_len = (*ctrl_reg & ST90TDS_CONT_NEXT_LEN_MASK) * 2;
 256         if (!read_len)
 257                 return 0; /* No more work */
 258
 259         if (WARN_ON((read_len < sizeof(struct wsm_hdr)) ||
 260                     (read_len > EFFECTIVE_BUF_SIZE))) {
 261                 pr_debug("Invalid read len: %zu (%04x)",
 262                          read_len, *ctrl_reg);
 263                 goto err;
 264         }
 265
 266         /* Add SIZE of PIGGYBACK reg (CONTROL Reg)
 267          * to the NEXT Message length + 2 Bytes for SKB
 268          */
 269         read_len = read_len + 2;
 270
 271         alloc_len = priv->hwbus_ops->align_size(
 272                 priv->hwbus_priv, read_len);
 273
 274         /* Check if not exceeding CW1200 capabilities */
 275         if (WARN_ON_ONCE(alloc_len > EFFECTIVE_BUF_SIZE)) {
 276                 pr_debug("Read aligned len: %zu\n",
 277                          alloc_len);
 278         }
 279
 280         skb_rx = dev_alloc_skb(alloc_len);
 281         if (WARN_ON(!skb_rx))
 282                 goto err;
 283
 284         skb_trim(skb_rx, 0);
 285         skb_put(skb_rx, read_len);
 286         data = skb_rx->data;
 287         if (WARN_ON(!data))
 288                 goto err;
 289
 290         if (WARN_ON(cw1200_data_read(priv, data, alloc_len))) {
 291                 pr_err("rx blew up, len %zu\n", alloc_len);
 292                 goto err;
 293         }
 294
 295         /* Piggyback */
 296         *ctrl_reg = __le16_to_cpu(
 297                 ((__le16 *)data)[alloc_len / 2 - 1]);
 298
 299         wsm = (struct wsm_hdr *)data;
 300         wsm_len = __le16_to_cpu(wsm->len);
 301         if (WARN_ON(wsm_len > read_len))
 302                 goto err;
 303
 304         if (priv->wsm_enable_wsm_dumps)
 305                 print_hex_dump_bytes("<-- ",
 306                                      DUMP_PREFIX_NONE,
 307                                      data, wsm_len);
 308
 309         wsm_id  = __le16_to_cpu(wsm->id) & 0xFFF;
 310         wsm_seq = (__le16_to_cpu(wsm->id) >> 13) & 7;
 311
 312         skb_trim(skb_rx, wsm_len);
 313
 314         if (wsm_id == 0x0800) {
 315                 wsm_handle_exception(priv,
 316                                      &data[sizeof(*wsm)],
 317                                      wsm_len - sizeof(*wsm));
 318                 goto err;
 319         } else if (!rx_resync) {
 320                 if (WARN_ON(wsm_seq != priv->wsm_rx_seq))
 321                         goto err;
 322         }
 323         priv->wsm_rx_seq = (wsm_seq + 1) & 7;
 324         rx_resync = 0;
 325
 326         if (wsm_id & 0x0400) {
 327                 int rc = wsm_release_tx_buffer(priv, 1);
 328                 if (WARN_ON(rc < 0))
 329                         return rc;
 330                 else if (rc > 0)
 331                         *tx = 1;
 332         }
 333
 334         /* cw1200_wsm_rx takes care on SKB livetime */
 335         if (WARN_ON(wsm_handle_rx(priv, wsm_id, wsm, &skb_rx)))
 336                 goto err;
 337
 338         if (skb_rx) {
 339                 dev_kfree_skb(skb_rx);
 340                 skb_rx = NULL;
 341         }
 342
 343         return 0;
 344
 345 err:
 346         if (skb_rx) {
 347                 dev_kfree_skb(skb_rx);
 348                 skb_rx = NULL;
 349         }
 350         return -1;
 351 }
 352
 353 static int cw1200_bh_tx_helper(struct cw1200_common *priv,
 354                                int *pending_tx,
 355                                int *tx_burst)
 356 {
 357         size_t tx_len;
 358         u8 *data;
 359         int ret;
 360         struct wsm_hdr *wsm;
 361
 362         if (priv->device_can_sleep) {
 363                 ret = cw1200_device_wakeup(priv);
 364                 if (WARN_ON(ret < 0)) { /* Error in wakeup */
 365                         *pending_tx = 1;
 366                         return 0;
 367                 } else if (ret) { /* Woke up */
 368                         priv->device_can_sleep = false;
 369                 } else { /* Did not awake */
 370                         *pending_tx = 1;
 371                         return 0;
 372                 }
 373         }
 374
 375         wsm_alloc_tx_buffer(priv);
 376         ret = wsm_get_tx(priv, &data, &tx_len, tx_burst);
 377         if (ret <= 0) {
 378                 wsm_release_tx_buffer(priv, 1);
 379                 if (WARN_ON(ret < 0))
 380                         return ret; /* Error */
 381                 return 0; /* No work */
 382         }
 383
 384         wsm = (struct wsm_hdr *)data;
 385         BUG_ON(tx_len < sizeof(*wsm));
 386         BUG_ON(__le16_to_cpu(wsm->len) != tx_len);
 387
 388         atomic_add(1, &priv->bh_tx);
 389
 390         tx_len = priv->hwbus_ops->align_size(
 391                 priv->hwbus_priv, tx_len);
 392
 393         /* Check if not exceeding CW1200 capabilities */
 394         if (WARN_ON_ONCE(tx_len > EFFECTIVE_BUF_SIZE))
 395                 pr_debug("Write aligned len: %zu\n", tx_len);
 396
 397         wsm->id &= __cpu_to_le16(0xffff ^ WSM_TX_SEQ(WSM_TX_SEQ_MAX));
 398         wsm->id |= __cpu_to_le16(WSM_TX_SEQ(priv->wsm_tx_seq));
 399
 400         if (WARN_ON(cw1200_data_write(priv, data, tx_len))) {
 401                 pr_err("tx blew up, len %zu\n", tx_len);
 402                 wsm_release_tx_buffer(priv, 1);
 403                 return -1; /* Error */
 404         }
 405
 406         if (priv->wsm_enable_wsm_dumps)
 407                 print_hex_dump_bytes("--> ",
 408                                      DUMP_PREFIX_NONE,
 409                                      data,
 410                                      __le16_to_cpu(wsm->len));
 411
 412         wsm_txed(priv, data);
 413         priv->wsm_tx_seq = (priv->wsm_tx_seq + 1) & WSM_TX_SEQ_MAX;
 414
 415         if (*tx_burst > 1) {
 416                 cw1200_debug_tx_burst(priv);
 417                 return 1; /* Work remains */
 418         }
 419
 420         return 0;
 421 }
 422
 423 static int cw1200_bh(void *arg)
 424 {
 425         struct cw1200_common *priv = arg;
 426         int rx, tx, term, suspend;
 427         u16 ctrl_reg = 0;
 428         int tx_allowed;
 429         int pending_tx = 0;
 430         int tx_burst;
 431         long status;
 432         u32 dummy;
 433         int ret;
 434
 435         for (;;) {
 436                 if (!priv->hw_bufs_used &&
 437                     priv->powersave_enabled &&
 438                     !priv->device_can_sleep &&
 439                     !atomic_read(&priv->recent_scan)) {
 440                         status = 1 * HZ;
 441                         pr_debug("[BH] Device wakedown. No data.\n");
 442                         cw1200_reg_write_16(priv, ST90TDS_CONTROL_REG_ID, 0);
 443                         priv->device_can_sleep = true;
 444                 } else if (priv->hw_bufs_used) {
 445                         /* Interrupt loss detection */
 446                         status = 1 * HZ;
 447                 } else {
 448                         status = MAX_SCHEDULE_TIMEOUT;
 449                 }
 450
 451                 /* Dummy Read for SDIO retry mechanism*/
 452                 if ((priv->hw_type != -1) &&
 453                     (atomic_read(&priv->bh_rx) == 0) &&
 454                     (atomic_read(&priv->bh_tx) == 0))
 455                         cw1200_reg_read(priv, ST90TDS_CONFIG_REG_ID,
 456                                         &dummy, sizeof(dummy));
 457
 458                 pr_debug("[BH] waiting ...\n");
 459                 status = wait_event_interruptible_timeout(priv->bh_wq, ({
 460                                 rx = atomic_xchg(&priv->bh_rx, 0);
 461                                 tx = atomic_xchg(&priv->bh_tx, 0);
 462                                 term = atomic_xchg(&priv->bh_term, 0);
 463                                 suspend = pending_tx ?
 464                                         0 : atomic_read(&priv->bh_suspend);
 465                                 (rx || tx || term || suspend || priv->bh_error);
 466                         }), status);
 467
 468                 pr_debug("[BH] - rx: %d, tx: %d, term: %d, bh_err: %d, suspend: %d, status: %ld\n",
 469                          rx, tx, term, suspend, priv->bh_error, status);
 470
 471                 /* Did an error occur? */
 472                 if ((status < 0 && status != -ERESTARTSYS) ||
 473                     term || priv->bh_error) {
 474                         break;
 475                 }
 476                 if (!status) {  /* wait_event timed out */
 477                         unsigned long timestamp = jiffies;
 478                         long timeout;
 479                         int pending = 0;
 480                         int i;
 481
 482                         /* Check to see if we have any outstanding frames */
 483                         if (priv->hw_bufs_used && (!rx || !tx)) {
 484                                 wiphy_warn(priv->hw->wiphy,
 485                                            "Missed interrupt? (%d frames outstanding)\n",
 486                                            priv->hw_bufs_used);
 487                                 rx = 1;
 488
 489                                 /* Get a timestamp of "oldest" frame */
 490                                 for (i = 0; i < 4; ++i)
 491                                         pending += cw1200_queue_get_xmit_timestamp(
 492                                                 &priv->tx_queue[i],
 493                                                 &timestamp,
 494                                                 priv->pending_frame_id);
 495
 496                                 /* Check if frame transmission is timed out.
 497                                  * Add an extra second with respect to possible
 498                                  * interrupt loss.
 499                                  */
 500                                 timeout = timestamp +
 501                                         WSM_CMD_LAST_CHANCE_TIMEOUT +
 502                                         1 * HZ  -
 503                                         jiffies;
 504
 505                                 /* And terminate BH thread if the frame is "stuck" */
 506                                 if (pending && timeout < 0) {
 507                                         wiphy_warn(priv->hw->wiphy,
 508                                                    "Timeout waiting for TX confirm (%d/%d pending, %ld vs %lu).\n",
 509                                                    priv->hw_bufs_used, pending,
 510                                                    timestamp, jiffies);
 511                                         break;
 512                                 }
 513                         } else if (!priv->device_can_sleep &&
 514                                    !atomic_read(&priv->recent_scan)) {
 515                                 pr_debug("[BH] Device wakedown. Timeout.\n");
 516                                 cw1200_reg_write_16(priv,
 517                                                     ST90TDS_CONTROL_REG_ID, 0);
 518                                 priv->device_can_sleep = true;
 519                         }
 520                         goto done;
 521                 } else if (suspend) {
 522                         pr_debug("[BH] Device suspend.\n");
 523                         if (priv->powersave_enabled) {
 524                                 pr_debug("[BH] Device wakedown. Suspend.\n");
 525                                 cw1200_reg_write_16(priv,
 526                                                     ST90TDS_CONTROL_REG_ID, 0);
 527                                 priv->device_can_sleep = true;
 528                         }
 529
 530                         atomic_set(&priv->bh_suspend, CW1200_BH_SUSPENDED);
 531                         wake_up(&priv->bh_evt_wq);
 532                         status = wait_event_interruptible(priv->bh_wq,
 533                                                           CW1200_BH_RESUME == atomic_read(&priv->bh_suspend));
 534                         if (status < 0) {
 535                                 wiphy_err(priv->hw->wiphy,
 536                                           "Failed to wait for resume: %ld.\n",
 537                                           status);
 538                                 break;
 539                         }
 540                         pr_debug("[BH] Device resume.\n");
 541                         atomic_set(&priv->bh_suspend, CW1200_BH_RESUMED);
 542                         wake_up(&priv->bh_evt_wq);
 543                         atomic_add(1, &priv->bh_rx);
 544                         goto done;
 545                 }
 546
 547         rx:
 548                 tx += pending_tx;
 549                 pending_tx = 0;
 550
 551                 if (cw1200_bh_read_ctrl_reg(priv, &ctrl_reg))
 552                         break;
 553
 554                 /* Don't bother trying to rx unless we have data to read */
 555                 if (ctrl_reg & ST90TDS_CONT_NEXT_LEN_MASK) {
 556                         ret = cw1200_bh_rx_helper(priv, &ctrl_reg, &tx);
 557                         if (ret < 0)
 558                                 break;
 559                         /* Double up here if there's more data.. */
 560                         if (ctrl_reg & ST90TDS_CONT_NEXT_LEN_MASK) {
 561                                 ret = cw1200_bh_rx_helper(priv, &ctrl_reg, &tx);
 562                                 if (ret < 0)
 563                                         break;
 564                         }
 565                 }
 566
 567         tx:
 568                 if (tx) {
 569                         tx = 0;
 570
 571                         BUG_ON(priv->hw_bufs_used > priv->wsm_caps.input_buffers);
 572                         tx_burst = priv->wsm_caps.input_buffers - priv->hw_bufs_used;
 573                         tx_allowed = tx_burst > 0;
 574
 575                         if (!tx_allowed) {
 576                                 /* Buffers full.  Ensure we process tx
 577                                  * after we handle rx..
 578                                  */
 579                                 pending_tx = tx;
 580                                 goto done_rx;
 581                         }
 582                         ret = cw1200_bh_tx_helper(priv, &pending_tx, &tx_burst);
 583                         if (ret < 0)
 584                                 break;
 585                         if (ret > 0) /* More to transmit */
 586                                 tx = ret;
 587
 588                         /* Re-read ctrl reg */
 589                         if (cw1200_bh_read_ctrl_reg(priv, &ctrl_reg))
 590                                 break;
 591                 }
 592
 593         done_rx:
 594                 if (priv->bh_error)
 595                         break;
 596                 if (ctrl_reg & ST90TDS_CONT_NEXT_LEN_MASK)
 597                         goto rx;
 598                 if (tx)
 599                         goto tx;
 600
 601         done:
 602                 /* Re-enable device interrupts */
 603                 priv->hwbus_ops->lock(priv->hwbus_priv);
 604                 __cw1200_irq_enable(priv, 1);
 605                 priv->hwbus_ops->unlock(priv->hwbus_priv);
 606         }
 607
 608         /* Explicitly disable device interrupts */
 609         priv->hwbus_ops->lock(priv->hwbus_priv);
 610         __cw1200_irq_enable(priv, 0);
 611         priv->hwbus_ops->unlock(priv->hwbus_priv);
 612
 613         if (!term) {
 614                 pr_err("[BH] Fatal error, exiting.\n");
 615                 priv->bh_error = 1;
 616                 /* TODO: schedule_work(recovery) */
 617         }
 618         return 0;
 619 }