kernel/drivers/staging/dgnc/dgnc_driver.c

   1 /*
   2  * Copyright 2003 Digi International (www.digi.com)
   3  *      Scott H Kilau <Scott_Kilau at digi dot com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2, or (at your option)
   8  * any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the
  12  * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  13  * PURPOSE.  See the GNU General Public License for more details.
  14  */
  15
  16 #include <linux/kernel.h>
  17 #include <linux/module.h>
  18 #include <linux/pci.h>
  19 #include <linux/slab.h>
  20 #include <linux/sched.h>
  21 #include "dgnc_driver.h"
  22 #include "dgnc_pci.h"
  23 #include "dgnc_mgmt.h"
  24 #include "dgnc_tty.h"
  25 #include "dgnc_cls.h"
  26 #include "dgnc_neo.h"
  27 #include "dgnc_sysfs.h"
  28
  29 MODULE_LICENSE("GPL");
  30 MODULE_AUTHOR("Digi International, http://www.digi.com");
  31 MODULE_DESCRIPTION("Driver for the Digi International Neo and Classic PCI based product line");
  32 MODULE_SUPPORTED_DEVICE("dgnc");
  33
  34 /**************************************************************************
  35  *
  36  * protos for this file
  37  *
  38  */
  39 static int              dgnc_start(void);
  40 static int              dgnc_finalize_board_init(struct dgnc_board *brd);
  41 static int              dgnc_found_board(struct pci_dev *pdev, int id);
  42 static void             dgnc_cleanup_board(struct dgnc_board *brd);
  43 static void             dgnc_poll_handler(ulong dummy);
  44 static int              dgnc_init_one(struct pci_dev *pdev,
  45                                       const struct pci_device_id *ent);
  46 static void             dgnc_do_remap(struct dgnc_board *brd);
  47
  48 /*
  49  * File operations permitted on Control/Management major.
  50  */
  51 static const struct file_operations dgnc_BoardFops = {
  52         .owner          =       THIS_MODULE,
  53         .unlocked_ioctl =       dgnc_mgmt_ioctl,
  54         .open           =       dgnc_mgmt_open,
  55         .release        =       dgnc_mgmt_close
  56 };
  57
  58 /*
  59  * Globals
  60  */
  61 uint                    dgnc_NumBoards;
  62 struct dgnc_board               *dgnc_Board[MAXBOARDS];
  63 DEFINE_SPINLOCK(dgnc_global_lock);
  64 DEFINE_SPINLOCK(dgnc_poll_lock); /* Poll scheduling lock */
  65 uint                    dgnc_Major;
  66 int                     dgnc_poll_tick = 20;    /* Poll interval - 20 ms */
  67
  68 /*
  69  * Static vars.
  70  */
  71 static struct class *dgnc_class;
  72
  73 /*
  74  * Poller stuff
  75  */
  76 static ulong            dgnc_poll_time; /* Time of next poll */
  77 static uint             dgnc_poll_stop; /* Used to tell poller to stop */
  78 static struct timer_list dgnc_poll_timer;
  79
  80 static const struct pci_device_id dgnc_pci_tbl[] = {
  81         {PCI_DEVICE(DIGI_VID, PCI_DEVICE_CLASSIC_4_DID),     .driver_data = 0},
  82         {PCI_DEVICE(DIGI_VID, PCI_DEVICE_CLASSIC_4_422_DID), .driver_data = 1},
  83         {PCI_DEVICE(DIGI_VID, PCI_DEVICE_CLASSIC_8_DID),     .driver_data = 2},
  84         {PCI_DEVICE(DIGI_VID, PCI_DEVICE_CLASSIC_8_422_DID), .driver_data = 3},
  85         {0,}
  86 };
  87 MODULE_DEVICE_TABLE(pci, dgnc_pci_tbl);
  88
  89 struct board_id {
  90         unsigned char *name;
  91         uint maxports;
  92         unsigned int is_pci_express;
  93 };
  94
  95 static struct board_id dgnc_Ids[] = {
  96         {       PCI_DEVICE_CLASSIC_4_PCI_NAME,          4,      0       },
  97         {       PCI_DEVICE_CLASSIC_4_422_PCI_NAME,      4,      0       },
  98         {       PCI_DEVICE_CLASSIC_8_PCI_NAME,          8,      0       },
  99         {       PCI_DEVICE_CLASSIC_8_422_PCI_NAME,      8,      0       },
 100         {       PCI_DEVICE_NEO_4_PCI_NAME,              4,      0       },
 101         {       PCI_DEVICE_NEO_8_PCI_NAME,              8,      0       },
 102         {       PCI_DEVICE_NEO_2DB9_PCI_NAME,           2,      0       },
 103         {       PCI_DEVICE_NEO_2DB9PRI_PCI_NAME,        2,      0       },
 104         {       PCI_DEVICE_NEO_2RJ45_PCI_NAME,          2,      0       },
 105         {       PCI_DEVICE_NEO_2RJ45PRI_PCI_NAME,       2,      0       },
 106         {       PCI_DEVICE_NEO_1_422_PCI_NAME,          1,      0       },
 107         {       PCI_DEVICE_NEO_1_422_485_PCI_NAME,      1,      0       },
 108         {       PCI_DEVICE_NEO_2_422_485_PCI_NAME,      2,      0       },
 109         {       PCI_DEVICE_NEO_EXPRESS_8_PCI_NAME,      8,      1       },
 110         {       PCI_DEVICE_NEO_EXPRESS_4_PCI_NAME,      4,      1       },
 111         {       PCI_DEVICE_NEO_EXPRESS_4RJ45_PCI_NAME,  4,      1       },
 112         {       PCI_DEVICE_NEO_EXPRESS_8RJ45_PCI_NAME,  8,      1       },
 113         {       NULL,                                   0,      0       }
 114 };
 115
 116 static struct pci_driver dgnc_driver = {
 117         .name           = "dgnc",
 118         .probe          = dgnc_init_one,
 119         .id_table       = dgnc_pci_tbl,
 120 };
 121
 122 /************************************************************************
 123  *
 124  * Driver load/unload functions
 125  *
 126  ************************************************************************/
 127
 128 /*
 129  * dgnc_cleanup_module()
 130  *
 131  * Module unload.  This is where it all ends.
 132  */
 133 static void dgnc_cleanup_module(void)
 134 {
 135         int i;
 136         unsigned long flags;
 137
 138         spin_lock_irqsave(&dgnc_poll_lock, flags);
 139         dgnc_poll_stop = 1;
 140         spin_unlock_irqrestore(&dgnc_poll_lock, flags);
 141
 142         /* Turn off poller right away. */
 143         del_timer_sync(&dgnc_poll_timer);
 144
 145         dgnc_remove_driver_sysfiles(&dgnc_driver);
 146
 147         device_destroy(dgnc_class, MKDEV(dgnc_Major, 0));
 148         class_destroy(dgnc_class);
 149         unregister_chrdev(dgnc_Major, "dgnc");
 150
 151         for (i = 0; i < dgnc_NumBoards; ++i) {
 152                 dgnc_remove_ports_sysfiles(dgnc_Board[i]);
 153                 dgnc_tty_uninit(dgnc_Board[i]);
 154                 dgnc_cleanup_board(dgnc_Board[i]);
 155         }
 156
 157         dgnc_tty_post_uninit();
 158
 159         if (dgnc_NumBoards)
 160                 pci_unregister_driver(&dgnc_driver);
 161 }
 162
 163 /*
 164  * init_module()
 165  *
 166  * Module load.  This is where it all starts.
 167  */
 168 static int __init dgnc_init_module(void)
 169 {
 170         int rc;
 171
 172         /*
 173          * Initialize global stuff
 174          */
 175         rc = dgnc_start();
 176
 177         if (rc < 0)
 178                 return rc;
 179
 180         /*
 181          * Find and configure all the cards
 182          */
 183         rc = pci_register_driver(&dgnc_driver);
 184
 185         /*
 186          * If something went wrong in the scan, bail out of driver.
 187          */
 188         if (rc < 0) {
 189                 /* Only unregister if it was actually registered. */
 190                 if (dgnc_NumBoards)
 191                         pci_unregister_driver(&dgnc_driver);
 192                 else
 193                         pr_warn("WARNING: dgnc driver load failed.  No Digi Neo or Classic boards found.\n");
 194
 195                 dgnc_cleanup_module();
 196         } else {
 197                 dgnc_create_driver_sysfiles(&dgnc_driver);
 198         }
 199
 200         return rc;
 201 }
 202
 203 module_init(dgnc_init_module);
 204 module_exit(dgnc_cleanup_module);
 205
 206 /*
 207  * Start of driver.
 208  */
 209 static int dgnc_start(void)
 210 {
 211         int rc = 0;
 212         unsigned long flags;
 213         struct device *dev;
 214
 215         /* make sure timer is initialized before we do anything else */
 216         init_timer(&dgnc_poll_timer);
 217
 218         /*
 219          * Register our base character device into the kernel.
 220          * This allows the download daemon to connect to the downld device
 221          * before any of the boards are init'ed.
 222          *
 223          * Register management/dpa devices
 224          */
 225         rc = register_chrdev(0, "dgnc", &dgnc_BoardFops);
 226         if (rc < 0) {
 227                 pr_err(DRVSTR ": Can't register dgnc driver device (%d)\n", rc);
 228                 return rc;
 229         }
 230         dgnc_Major = rc;
 231
 232         dgnc_class = class_create(THIS_MODULE, "dgnc_mgmt");
 233         if (IS_ERR(dgnc_class)) {
 234                 rc = PTR_ERR(dgnc_class);
 235                 pr_err(DRVSTR ": Can't create dgnc_mgmt class (%d)\n", rc);
 236                 goto failed_class;
 237         }
 238
 239         dev = device_create(dgnc_class, NULL,
 240                             MKDEV(dgnc_Major, 0),
 241                         NULL, "dgnc_mgmt");
 242         if (IS_ERR(dev)) {
 243                 rc = PTR_ERR(dev);
 244                 pr_err(DRVSTR ": Can't create device (%d)\n", rc);
 245                 goto failed_device;
 246         }
 247
 248         /*
 249          * Init any global tty stuff.
 250          */
 251         rc = dgnc_tty_preinit();
 252
 253         if (rc < 0) {
 254                 pr_err(DRVSTR ": tty preinit - not enough memory (%d)\n", rc);
 255                 goto failed_tty;
 256         }
 257
 258         /* Start the poller */
 259         spin_lock_irqsave(&dgnc_poll_lock, flags);
 260         setup_timer(&dgnc_poll_timer, dgnc_poll_handler, 0);
 261         dgnc_poll_time = jiffies + dgnc_jiffies_from_ms(dgnc_poll_tick);
 262         dgnc_poll_timer.expires = dgnc_poll_time;
 263         spin_unlock_irqrestore(&dgnc_poll_lock, flags);
 264
 265         add_timer(&dgnc_poll_timer);
 266
 267         return 0;
 268
 269 failed_tty:
 270         device_destroy(dgnc_class, MKDEV(dgnc_Major, 0));
 271 failed_device:
 272         class_destroy(dgnc_class);
 273 failed_class:
 274         unregister_chrdev(dgnc_Major, "dgnc");
 275         return rc;
 276 }
 277
 278 /* returns count (>= 0), or negative on error */
 279 static int dgnc_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 280 {
 281         int rc;
 282
 283         /* wake up and enable device */
 284         rc = pci_enable_device(pdev);
 285
 286         if (rc < 0) {
 287                 rc = -EIO;
 288         } else {
 289                 rc = dgnc_found_board(pdev, ent->driver_data);
 290                 if (rc == 0)
 291                         dgnc_NumBoards++;
 292         }
 293         return rc;
 294 }
 295
 296 /*
 297  * dgnc_cleanup_board()
 298  *
 299  * Free all the memory associated with a board
 300  */
 301 static void dgnc_cleanup_board(struct dgnc_board *brd)
 302 {
 303         int i = 0;
 304
 305         if (!brd || brd->magic != DGNC_BOARD_MAGIC)
 306                 return;
 307
 308         switch (brd->device) {
 309         case PCI_DEVICE_CLASSIC_4_DID:
 310         case PCI_DEVICE_CLASSIC_8_DID:
 311         case PCI_DEVICE_CLASSIC_4_422_DID:
 312         case PCI_DEVICE_CLASSIC_8_422_DID:
 313
 314                 /* Tell card not to interrupt anymore. */
 315                 outb(0, brd->iobase + 0x4c);
 316                 break;
 317
 318         default:
 319                 break;
 320         }
 321
 322         if (brd->irq)
 323                 free_irq(brd->irq, brd);
 324
 325         tasklet_kill(&brd->helper_tasklet);
 326
 327         if (brd->re_map_membase) {
 328                 iounmap(brd->re_map_membase);
 329                 brd->re_map_membase = NULL;
 330         }
 331
 332         if (brd->msgbuf_head) {
 333                 unsigned long flags;
 334
 335                 spin_lock_irqsave(&dgnc_global_lock, flags);
 336                 brd->msgbuf = NULL;
 337                 dev_dbg(&brd->pdev->dev, "%s\n", brd->msgbuf_head);
 338                 kfree(brd->msgbuf_head);
 339                 brd->msgbuf_head = NULL;
 340                 spin_unlock_irqrestore(&dgnc_global_lock, flags);
 341         }
 342
 343         /* Free all allocated channels structs */
 344         for (i = 0; i < MAXPORTS ; i++) {
 345                 if (brd->channels[i]) {
 346                         kfree(brd->channels[i]->ch_rqueue);
 347                         kfree(brd->channels[i]->ch_equeue);
 348                         kfree(brd->channels[i]->ch_wqueue);
 349                         kfree(brd->channels[i]);
 350                         brd->channels[i] = NULL;
 351                 }
 352         }
 353
 354         dgnc_Board[brd->boardnum] = NULL;
 355
 356         kfree(brd);
 357 }
 358
 359 /*
 360  * dgnc_found_board()
 361  *
 362  * A board has been found, init it.
 363  */
 364 static int dgnc_found_board(struct pci_dev *pdev, int id)
 365 {
 366         struct dgnc_board *brd;
 367         unsigned int pci_irq;
 368         int i = 0;
 369         int rc = 0;
 370         unsigned long flags;
 371
 372         /* get the board structure and prep it */
 373         dgnc_Board[dgnc_NumBoards] = kzalloc(sizeof(*brd), GFP_KERNEL);
 374         brd = dgnc_Board[dgnc_NumBoards];
 375
 376         if (!brd)
 377                 return -ENOMEM;
 378
 379         /* make a temporary message buffer for the boot messages */
 380         brd->msgbuf_head = kcalloc(8192, sizeof(u8), GFP_KERNEL);
 381         brd->msgbuf = brd->msgbuf_head;
 382
 383         if (!brd->msgbuf) {
 384                 kfree(brd);
 385                 return -ENOMEM;
 386         }
 387
 388         /* store the info for the board we've found */
 389         brd->magic = DGNC_BOARD_MAGIC;
 390         brd->boardnum = dgnc_NumBoards;
 391         brd->vendor = dgnc_pci_tbl[id].vendor;
 392         brd->device = dgnc_pci_tbl[id].device;
 393         brd->pdev = pdev;
 394         brd->pci_bus = pdev->bus->number;
 395         brd->pci_slot = PCI_SLOT(pdev->devfn);
 396         brd->name = dgnc_Ids[id].name;
 397         brd->maxports = dgnc_Ids[id].maxports;
 398         if (dgnc_Ids[i].is_pci_express)
 399                 brd->bd_flags |= BD_IS_PCI_EXPRESS;
 400         brd->dpastatus = BD_NOFEP;
 401         init_waitqueue_head(&brd->state_wait);
 402
 403         spin_lock_init(&brd->bd_lock);
 404         spin_lock_init(&brd->bd_intr_lock);
 405
 406         brd->state              = BOARD_FOUND;
 407
 408         for (i = 0; i < MAXPORTS; i++)
 409                 brd->channels[i] = NULL;
 410
 411         /* store which card & revision we have */
 412         pci_read_config_word(pdev, PCI_SUBSYSTEM_VENDOR_ID, &brd->subvendor);
 413         pci_read_config_word(pdev, PCI_SUBSYSTEM_ID, &brd->subdevice);
 414         pci_read_config_byte(pdev, PCI_REVISION_ID, &brd->rev);
 415
 416         pci_irq = pdev->irq;
 417         brd->irq = pci_irq;
 418
 419         switch (brd->device) {
 420         case PCI_DEVICE_CLASSIC_4_DID:
 421         case PCI_DEVICE_CLASSIC_8_DID:
 422         case PCI_DEVICE_CLASSIC_4_422_DID:
 423         case PCI_DEVICE_CLASSIC_8_422_DID:
 424
 425                 brd->dpatype = T_CLASSIC | T_PCIBUS;
 426
 427                 /*
 428                  * For PCI ClassicBoards
 429                  * PCI Local Address (i.e. "resource" number) space
 430                  * 0    PLX Memory Mapped Config
 431                  * 1    PLX I/O Mapped Config
 432                  * 2    I/O Mapped UARTs and Status
 433                  * 3    Memory Mapped VPD
 434                  * 4    Memory Mapped UARTs and Status
 435                  */
 436
 437                 /* get the PCI Base Address Registers */
 438                 brd->membase = pci_resource_start(pdev, 4);
 439
 440                 if (!brd->membase) {
 441                         dev_err(&brd->pdev->dev,
 442                                 "Card has no PCI IO resources, failing.\n");
 443                         return -ENODEV;
 444                 }
 445
 446                 brd->membase_end = pci_resource_end(pdev, 4);
 447
 448                 if (brd->membase & 1)
 449                         brd->membase &= ~3;
 450                 else
 451                         brd->membase &= ~15;
 452
 453                 brd->iobase     = pci_resource_start(pdev, 1);
 454                 brd->iobase_end = pci_resource_end(pdev, 1);
 455                 brd->iobase     = ((unsigned int)(brd->iobase)) & 0xFFFE;
 456
 457                 /* Assign the board_ops struct */
 458                 brd->bd_ops = &dgnc_cls_ops;
 459
 460                 brd->bd_uart_offset = 0x8;
 461                 brd->bd_dividend = 921600;
 462
 463                 dgnc_do_remap(brd);
 464
 465                 /* Get and store the board VPD, if it exists */
 466                 brd->bd_ops->vpd(brd);
 467
 468                 /*
 469                  * Enable Local Interrupt 1               (0x1),
 470                  * Local Interrupt 1 Polarity Active high (0x2),
 471                  * Enable PCI interrupt                   (0x40)
 472                  */
 473                 outb(0x43, brd->iobase + 0x4c);
 474
 475                 break;
 476
 477         case PCI_DEVICE_NEO_4_DID:
 478         case PCI_DEVICE_NEO_8_DID:
 479         case PCI_DEVICE_NEO_2DB9_DID:
 480         case PCI_DEVICE_NEO_2DB9PRI_DID:
 481         case PCI_DEVICE_NEO_2RJ45_DID:
 482         case PCI_DEVICE_NEO_2RJ45PRI_DID:
 483         case PCI_DEVICE_NEO_1_422_DID:
 484         case PCI_DEVICE_NEO_1_422_485_DID:
 485         case PCI_DEVICE_NEO_2_422_485_DID:
 486         case PCI_DEVICE_NEO_EXPRESS_8_DID:
 487         case PCI_DEVICE_NEO_EXPRESS_4_DID:
 488         case PCI_DEVICE_NEO_EXPRESS_4RJ45_DID:
 489         case PCI_DEVICE_NEO_EXPRESS_8RJ45_DID:
 490
 491                 /*
 492                  * This chip is set up 100% when we get to it.
 493                  * No need to enable global interrupts or anything.
 494                  */
 495                 if (brd->bd_flags & BD_IS_PCI_EXPRESS)
 496                         brd->dpatype = T_NEO_EXPRESS | T_PCIBUS;
 497                 else
 498                         brd->dpatype = T_NEO | T_PCIBUS;
 499
 500                 /* get the PCI Base Address Registers */
 501                 brd->membase     = pci_resource_start(pdev, 0);
 502                 brd->membase_end = pci_resource_end(pdev, 0);
 503
 504                 if (brd->membase & 1)
 505                         brd->membase &= ~3;
 506                 else
 507                         brd->membase &= ~15;
 508
 509                 /* Assign the board_ops struct */
 510                 brd->bd_ops = &dgnc_neo_ops;
 511
 512                 brd->bd_uart_offset = 0x200;
 513                 brd->bd_dividend = 921600;
 514
 515                 dgnc_do_remap(brd);
 516
 517                 if (brd->re_map_membase) {
 518                         /* Read and store the dvid after remapping */
 519                         brd->dvid = readb(brd->re_map_membase + 0x8D);
 520
 521                         /* Get and store the board VPD, if it exists */
 522                         brd->bd_ops->vpd(brd);
 523                 }
 524                 break;
 525
 526         default:
 527                 dev_err(&brd->pdev->dev,
 528                         "Didn't find any compatible Neo/Classic PCI boards.\n");
 529                 return -ENXIO;
 530         }
 531
 532         /*
 533          * Do tty device initialization.
 534          */
 535
 536         rc = dgnc_tty_register(brd);
 537         if (rc < 0) {
 538                 pr_err(DRVSTR ": Can't register tty devices (%d)\n", rc);
 539                 goto failed;
 540         }
 541
 542         rc = dgnc_finalize_board_init(brd);
 543         if (rc < 0) {
 544                 pr_err(DRVSTR ": Can't finalize board init (%d)\n", rc);
 545                 goto failed;
 546         }
 547
 548         rc = dgnc_tty_init(brd);
 549         if (rc < 0) {
 550                 pr_err(DRVSTR ": Can't init tty devices (%d)\n", rc);
 551                 goto failed;
 552         }
 553
 554         brd->state = BOARD_READY;
 555         brd->dpastatus = BD_RUNNING;
 556
 557         dgnc_create_ports_sysfiles(brd);
 558
 559         /* init our poll helper tasklet */
 560         tasklet_init(&brd->helper_tasklet,
 561                      brd->bd_ops->tasklet,
 562                      (unsigned long)brd);
 563
 564         spin_lock_irqsave(&dgnc_global_lock, flags);
 565         brd->msgbuf = NULL;
 566         dev_dbg(&brd->pdev->dev, "%s\n", brd->msgbuf_head);
 567         kfree(brd->msgbuf_head);
 568         brd->msgbuf_head = NULL;
 569         spin_unlock_irqrestore(&dgnc_global_lock, flags);
 570
 571         wake_up_interruptible(&brd->state_wait);
 572
 573         return 0;
 574
 575 failed:
 576         dgnc_tty_uninit(brd);
 577         brd->state = BOARD_FAILED;
 578         brd->dpastatus = BD_NOFEP;
 579
 580         return -ENXIO;
 581 }
 582
 583 static int dgnc_finalize_board_init(struct dgnc_board *brd)
 584 {
 585         int rc = 0;
 586
 587         if (!brd || brd->magic != DGNC_BOARD_MAGIC)
 588                 return -ENODEV;
 589
 590         if (brd->irq) {
 591                 rc = request_irq(brd->irq, brd->bd_ops->intr,
 592                                  IRQF_SHARED, "DGNC", brd);
 593
 594                 if (rc) {
 595                         dev_err(&brd->pdev->dev,
 596                                 "Failed to hook IRQ %d\n", brd->irq);
 597                         brd->state = BOARD_FAILED;
 598                         brd->dpastatus = BD_NOFEP;
 599                         rc = -ENODEV;
 600                 }
 601         }
 602         return rc;
 603 }
 604
 605 /*
 606  * Remap PCI memory.
 607  */
 608 static void dgnc_do_remap(struct dgnc_board *brd)
 609 {
 610         if (!brd || brd->magic != DGNC_BOARD_MAGIC)
 611                 return;
 612
 613         brd->re_map_membase = ioremap(brd->membase, 0x1000);
 614 }
 615
 616 /*****************************************************************************
 617 *
 618 * Function:
 619 *
 620 *    dgnc_poll_handler
 621 *
 622 * Author:
 623 *
 624 *    Scott H Kilau
 625 *
 626 * Parameters:
 627 *
 628 *    dummy -- ignored
 629 *
 630 * Return Values:
 631 *
 632 *    none
 633 *
 634 * Description:
 635 *
 636 *    As each timer expires, it determines (a) whether the "transmit"
 637 *    waiter needs to be woken up, and (b) whether the poller needs to
 638 *    be rescheduled.
 639 *
 640 ******************************************************************************/
 641
 642 static void dgnc_poll_handler(ulong dummy)
 643 {
 644         struct dgnc_board *brd;
 645         unsigned long flags;
 646         int i;
 647         unsigned long new_time;
 648
 649         /* Go thru each board, kicking off a tasklet for each if needed */
 650         for (i = 0; i < dgnc_NumBoards; i++) {
 651                 brd = dgnc_Board[i];
 652
 653                 spin_lock_irqsave(&brd->bd_lock, flags);
 654
 655                 /* If board is in a failed state don't schedule a tasklet */
 656                 if (brd->state == BOARD_FAILED) {
 657                         spin_unlock_irqrestore(&brd->bd_lock, flags);
 658                         continue;
 659                 }
 660
 661                 /* Schedule a poll helper task */
 662                 tasklet_schedule(&brd->helper_tasklet);
 663
 664                 spin_unlock_irqrestore(&brd->bd_lock, flags);
 665         }
 666
 667         /*
 668          * Schedule ourself back at the nominal wakeup interval.
 669          */
 670         spin_lock_irqsave(&dgnc_poll_lock, flags);
 671         dgnc_poll_time += dgnc_jiffies_from_ms(dgnc_poll_tick);
 672
 673         new_time = dgnc_poll_time - jiffies;
 674
 675         if ((ulong)new_time >= 2 * dgnc_poll_tick)
 676                 dgnc_poll_time = jiffies + dgnc_jiffies_from_ms(dgnc_poll_tick);
 677
 678         setup_timer(&dgnc_poll_timer, dgnc_poll_handler, 0);
 679         dgnc_poll_timer.expires = dgnc_poll_time;
 680         spin_unlock_irqrestore(&dgnc_poll_lock, flags);
 681
 682         if (!dgnc_poll_stop)
 683                 add_timer(&dgnc_poll_timer);
 684 }