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
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/pci.h>
  20 #include <linux/slab.h>
  21 #include <linux/sched.h>
  22 #include "dgnc_driver.h"
  23 #include "dgnc_pci.h"
  24 #include "dgnc_mgmt.h"
  25 #include "dgnc_tty.h"
  26 #include "dgnc_cls.h"
  27 #include "dgnc_neo.h"
  28 #include "dgnc_sysfs.h"
  29
  30 MODULE_LICENSE("GPL");
  31 MODULE_AUTHOR("Digi International, http://www.digi.com");
  32 MODULE_DESCRIPTION("Driver for the Digi International Neo and Classic PCI based product line");
  33 MODULE_SUPPORTED_DEVICE("dgnc");
  34
  35 /**************************************************************************
  36  *
  37  * protos for this file
  38  *
  39  */
  40 static int              dgnc_start(void);
  41 static int              dgnc_finalize_board_init(struct dgnc_board *brd);
  42 static void             dgnc_init_globals(void);
  43 static int              dgnc_found_board(struct pci_dev *pdev, int id);
  44 static void             dgnc_cleanup_board(struct dgnc_board *brd);
  45 static void             dgnc_poll_handler(ulong dummy);
  46 static int              dgnc_init_one(struct pci_dev *pdev,
  47                                       const struct pci_device_id *ent);
  48 static void             dgnc_do_remap(struct dgnc_board *brd);
  49
  50 /*
  51  * File operations permitted on Control/Management major.
  52  */
  53 static const struct file_operations dgnc_BoardFops = {
  54         .owner          =       THIS_MODULE,
  55         .unlocked_ioctl =       dgnc_mgmt_ioctl,
  56         .open           =       dgnc_mgmt_open,
  57         .release        =       dgnc_mgmt_close
  58 };
  59
  60
  61 /*
  62  * Globals
  63  */
  64 uint                    dgnc_NumBoards;
  65 struct dgnc_board               *dgnc_Board[MAXBOARDS];
  66 DEFINE_SPINLOCK(dgnc_global_lock);
  67 uint                    dgnc_Major;
  68 int                     dgnc_poll_tick = 20;    /* Poll interval - 20 ms */
  69
  70 /*
  71  * Static vars.
  72  */
  73 static struct class *dgnc_class;
  74
  75 /*
  76  * Poller stuff
  77  */
  78 static DEFINE_SPINLOCK(dgnc_poll_lock); /* Poll scheduling lock */
  79 static ulong            dgnc_poll_time; /* Time of next poll */
  80 static uint             dgnc_poll_stop; /* Used to tell poller to stop */
  81 static struct timer_list dgnc_poll_timer;
  82
  83
  84 static const struct pci_device_id dgnc_pci_tbl[] = {
  85         {PCI_DEVICE(DIGI_VID, PCI_DEVICE_CLASSIC_4_DID),     .driver_data = 0},
  86         {PCI_DEVICE(DIGI_VID, PCI_DEVICE_CLASSIC_4_422_DID), .driver_data = 1},
  87         {PCI_DEVICE(DIGI_VID, PCI_DEVICE_CLASSIC_8_DID),     .driver_data = 2},
  88         {PCI_DEVICE(DIGI_VID, PCI_DEVICE_CLASSIC_8_422_DID), .driver_data = 3},
  89         {0,}
  90 };
  91 MODULE_DEVICE_TABLE(pci, dgnc_pci_tbl);
  92
  93 struct board_id {
  94         unsigned char *name;
  95         uint maxports;
  96         unsigned int is_pci_express;
  97 };
  98
  99 static struct board_id dgnc_Ids[] = {
 100         {       PCI_DEVICE_CLASSIC_4_PCI_NAME,          4,      0       },
 101         {       PCI_DEVICE_CLASSIC_4_422_PCI_NAME,      4,      0       },
 102         {       PCI_DEVICE_CLASSIC_8_PCI_NAME,          8,      0       },
 103         {       PCI_DEVICE_CLASSIC_8_422_PCI_NAME,      8,      0       },
 104         {       PCI_DEVICE_NEO_4_PCI_NAME,              4,      0       },
 105         {       PCI_DEVICE_NEO_8_PCI_NAME,              8,      0       },
 106         {       PCI_DEVICE_NEO_2DB9_PCI_NAME,           2,      0       },
 107         {       PCI_DEVICE_NEO_2DB9PRI_PCI_NAME,        2,      0       },
 108         {       PCI_DEVICE_NEO_2RJ45_PCI_NAME,          2,      0       },
 109         {       PCI_DEVICE_NEO_2RJ45PRI_PCI_NAME,       2,      0       },
 110         {       PCI_DEVICE_NEO_1_422_PCI_NAME,          1,      0       },
 111         {       PCI_DEVICE_NEO_1_422_485_PCI_NAME,      1,      0       },
 112         {       PCI_DEVICE_NEO_2_422_485_PCI_NAME,      2,      0       },
 113         {       PCI_DEVICE_NEO_EXPRESS_8_PCI_NAME,      8,      1       },
 114         {       PCI_DEVICE_NEO_EXPRESS_4_PCI_NAME,      4,      1       },
 115         {       PCI_DEVICE_NEO_EXPRESS_4RJ45_PCI_NAME,  4,      1       },
 116         {       PCI_DEVICE_NEO_EXPRESS_8RJ45_PCI_NAME,  8,      1       },
 117         {       NULL,                                   0,      0       }
 118 };
 119
 120 static struct pci_driver dgnc_driver = {
 121         .name           = "dgnc",
 122         .probe          = dgnc_init_one,
 123         .id_table       = dgnc_pci_tbl,
 124 };
 125
 126 /************************************************************************
 127  *
 128  * Driver load/unload functions
 129  *
 130  ************************************************************************/
 131
 132 /*
 133  * dgnc_cleanup_module()
 134  *
 135  * Module unload.  This is where it all ends.
 136  */
 137 static void dgnc_cleanup_module(void)
 138 {
 139         int i;
 140         unsigned long flags;
 141
 142         spin_lock_irqsave(&dgnc_poll_lock, flags);
 143         dgnc_poll_stop = 1;
 144         spin_unlock_irqrestore(&dgnc_poll_lock, flags);
 145
 146         /* Turn off poller right away. */
 147         del_timer_sync(&dgnc_poll_timer);
 148
 149         dgnc_remove_driver_sysfiles(&dgnc_driver);
 150
 151         device_destroy(dgnc_class, MKDEV(dgnc_Major, 0));
 152         class_destroy(dgnc_class);
 153         unregister_chrdev(dgnc_Major, "dgnc");
 154
 155         for (i = 0; i < dgnc_NumBoards; ++i) {
 156                 dgnc_remove_ports_sysfiles(dgnc_Board[i]);
 157                 dgnc_tty_uninit(dgnc_Board[i]);
 158                 dgnc_cleanup_board(dgnc_Board[i]);
 159         }
 160
 161         dgnc_tty_post_uninit();
 162
 163         if (dgnc_NumBoards)
 164                 pci_unregister_driver(&dgnc_driver);
 165 }
 166
 167 /*
 168  * init_module()
 169  *
 170  * Module load.  This is where it all starts.
 171  */
 172 static int __init dgnc_init_module(void)
 173 {
 174         int rc = 0;
 175
 176         /*
 177          * Initialize global stuff
 178          */
 179         rc = dgnc_start();
 180
 181         if (rc < 0)
 182                 return rc;
 183
 184         /*
 185          * Find and configure all the cards
 186          */
 187         rc = pci_register_driver(&dgnc_driver);
 188
 189         /*
 190          * If something went wrong in the scan, bail out of driver.
 191          */
 192         if (rc < 0) {
 193                 /* Only unregister if it was actually registered. */
 194                 if (dgnc_NumBoards)
 195                         pci_unregister_driver(&dgnc_driver);
 196                 else
 197                         pr_warn("WARNING: dgnc driver load failed.  No Digi Neo or Classic boards found.\n");
 198
 199                 dgnc_cleanup_module();
 200         } else {
 201                 dgnc_create_driver_sysfiles(&dgnc_driver);
 202         }
 203
 204         return rc;
 205 }
 206
 207 module_init(dgnc_init_module);
 208 module_exit(dgnc_cleanup_module);
 209
 210 /*
 211  * Start of driver.
 212  */
 213 static int dgnc_start(void)
 214 {
 215         int rc = 0;
 216         unsigned long flags;
 217         struct device *dev;
 218
 219         /* make sure that the globals are init'd before we do anything else */
 220         dgnc_init_globals();
 221
 222         /*
 223          * Register our base character device into the kernel.
 224          * This allows the download daemon to connect to the downld device
 225          * before any of the boards are init'ed.
 226          *
 227          * Register management/dpa devices
 228          */
 229         rc = register_chrdev(0, "dgnc", &dgnc_BoardFops);
 230         if (rc < 0) {
 231                 pr_err(DRVSTR ": Can't register dgnc driver device (%d)\n", rc);
 232                 return rc;
 233         }
 234         dgnc_Major = rc;
 235
 236         dgnc_class = class_create(THIS_MODULE, "dgnc_mgmt");
 237         if (IS_ERR(dgnc_class)) {
 238                 rc = PTR_ERR(dgnc_class);
 239                 pr_err(DRVSTR ": Can't create dgnc_mgmt class (%d)\n", rc);
 240                 goto failed_class;
 241         }
 242
 243         dev = device_create(dgnc_class, NULL,
 244                         MKDEV(dgnc_Major, 0),
 245                         NULL, "dgnc_mgmt");
 246         if (IS_ERR(dev)) {
 247                 rc = PTR_ERR(dev);
 248                 pr_err(DRVSTR ": Can't create device (%d)\n", rc);
 249                 goto failed_device;
 250         }
 251
 252         /*
 253          * Init any global tty stuff.
 254          */
 255         rc = dgnc_tty_preinit();
 256
 257         if (rc < 0) {
 258                 pr_err(DRVSTR ": tty preinit - not enough memory (%d)\n", rc);
 259                 goto failed_tty;
 260         }
 261
 262         /* Start the poller */
 263         spin_lock_irqsave(&dgnc_poll_lock, flags);
 264         setup_timer(&dgnc_poll_timer, dgnc_poll_handler, 0);
 265         dgnc_poll_time = jiffies + dgnc_jiffies_from_ms(dgnc_poll_tick);
 266         dgnc_poll_timer.expires = dgnc_poll_time;
 267         spin_unlock_irqrestore(&dgnc_poll_lock, flags);
 268
 269         add_timer(&dgnc_poll_timer);
 270
 271         return 0;
 272
 273 failed_tty:
 274         device_destroy(dgnc_class, MKDEV(dgnc_Major, 0));
 275 failed_device:
 276         class_destroy(dgnc_class);
 277 failed_class:
 278         unregister_chrdev(dgnc_Major, "dgnc");
 279         return rc;
 280 }
 281
 282 /* returns count (>= 0), or negative on error */
 283 static int dgnc_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 284 {
 285         int rc;
 286
 287         /* wake up and enable device */
 288         rc = pci_enable_device(pdev);
 289
 290         if (rc < 0) {
 291                 rc = -EIO;
 292         } else {
 293                 rc = dgnc_found_board(pdev, ent->driver_data);
 294                 if (rc == 0)
 295                         dgnc_NumBoards++;
 296         }
 297         return rc;
 298 }
 299
 300 /*
 301  * dgnc_cleanup_board()
 302  *
 303  * Free all the memory associated with a board
 304  */
 305 static void dgnc_cleanup_board(struct dgnc_board *brd)
 306 {
 307         int i = 0;
 308
 309         if (!brd || brd->magic != DGNC_BOARD_MAGIC)
 310                 return;
 311
 312         switch (brd->device) {
 313         case PCI_DEVICE_CLASSIC_4_DID:
 314         case PCI_DEVICE_CLASSIC_8_DID:
 315         case PCI_DEVICE_CLASSIC_4_422_DID:
 316         case PCI_DEVICE_CLASSIC_8_422_DID:
 317
 318                 /* Tell card not to interrupt anymore. */
 319                 outb(0, brd->iobase + 0x4c);
 320                 break;
 321
 322         default:
 323                 break;
 324         }
 325
 326         if (brd->irq)
 327                 free_irq(brd->irq, brd);
 328
 329         tasklet_kill(&brd->helper_tasklet);
 330
 331         if (brd->re_map_membase) {
 332                 iounmap(brd->re_map_membase);
 333                 brd->re_map_membase = NULL;
 334         }
 335
 336         if (brd->msgbuf_head) {
 337                 unsigned long flags;
 338
 339                 spin_lock_irqsave(&dgnc_global_lock, flags);
 340                 brd->msgbuf = NULL;
 341                 dev_dbg(&brd->pdev->dev, "%s\n", brd->msgbuf_head);
 342                 kfree(brd->msgbuf_head);
 343                 brd->msgbuf_head = NULL;
 344                 spin_unlock_irqrestore(&dgnc_global_lock, flags);
 345         }
 346
 347         /* Free all allocated channels structs */
 348         for (i = 0; i < MAXPORTS ; i++) {
 349                 if (brd->channels[i]) {
 350                         kfree(brd->channels[i]->ch_rqueue);
 351                         kfree(brd->channels[i]->ch_equeue);
 352                         kfree(brd->channels[i]->ch_wqueue);
 353                         kfree(brd->channels[i]);
 354                         brd->channels[i] = NULL;
 355                 }
 356         }
 357
 358         kfree(brd->flipbuf);
 359
 360         dgnc_Board[brd->boardnum] = NULL;
 361
 362         kfree(brd);
 363 }
 364
 365
 366 /*
 367  * dgnc_found_board()
 368  *
 369  * A board has been found, init it.
 370  */
 371 static int dgnc_found_board(struct pci_dev *pdev, int id)
 372 {
 373         struct dgnc_board *brd;
 374         unsigned int pci_irq;
 375         int i = 0;
 376         int rc = 0;
 377         unsigned long flags;
 378
 379         /* get the board structure and prep it */
 380         dgnc_Board[dgnc_NumBoards] = kzalloc(sizeof(*brd), GFP_KERNEL);
 381         brd = dgnc_Board[dgnc_NumBoards];
 382
 383         if (!brd)
 384                 return -ENOMEM;
 385
 386         /* make a temporary message buffer for the boot messages */
 387         brd->msgbuf_head = kcalloc(8192, sizeof(u8), GFP_KERNEL);
 388         brd->msgbuf = brd->msgbuf_head;
 389
 390         if (!brd->msgbuf) {
 391                 kfree(brd);
 392                 return -ENOMEM;
 393         }
 394
 395         /* store the info for the board we've found */
 396         brd->magic = DGNC_BOARD_MAGIC;
 397         brd->boardnum = dgnc_NumBoards;
 398         brd->vendor = dgnc_pci_tbl[id].vendor;
 399         brd->device = dgnc_pci_tbl[id].device;
 400         brd->pdev = pdev;
 401         brd->pci_bus = pdev->bus->number;
 402         brd->pci_slot = PCI_SLOT(pdev->devfn);
 403         brd->name = dgnc_Ids[id].name;
 404         brd->maxports = dgnc_Ids[id].maxports;
 405         if (dgnc_Ids[i].is_pci_express)
 406                 brd->bd_flags |= BD_IS_PCI_EXPRESS;
 407         brd->dpastatus = BD_NOFEP;
 408         init_waitqueue_head(&brd->state_wait);
 409
 410         spin_lock_init(&brd->bd_lock);
 411         spin_lock_init(&brd->bd_intr_lock);
 412
 413         brd->state              = BOARD_FOUND;
 414
 415         for (i = 0; i < MAXPORTS; i++)
 416                 brd->channels[i] = NULL;
 417
 418         /* store which card & revision we have */
 419         pci_read_config_word(pdev, PCI_SUBSYSTEM_VENDOR_ID, &brd->subvendor);
 420         pci_read_config_word(pdev, PCI_SUBSYSTEM_ID, &brd->subdevice);
 421         pci_read_config_byte(pdev, PCI_REVISION_ID, &brd->rev);
 422
 423         pci_irq = pdev->irq;
 424         brd->irq = pci_irq;
 425
 426
 427         switch (brd->device) {
 428
 429         case PCI_DEVICE_CLASSIC_4_DID:
 430         case PCI_DEVICE_CLASSIC_8_DID:
 431         case PCI_DEVICE_CLASSIC_4_422_DID:
 432         case PCI_DEVICE_CLASSIC_8_422_DID:
 433
 434                 brd->dpatype = T_CLASSIC | T_PCIBUS;
 435
 436                 /*
 437                  * For PCI ClassicBoards
 438                  * PCI Local Address (i.e. "resource" number) space
 439                  * 0    PLX Memory Mapped Config
 440                  * 1    PLX I/O Mapped Config
 441                  * 2    I/O Mapped UARTs and Status
 442                  * 3    Memory Mapped VPD
 443                  * 4    Memory Mapped UARTs and Status
 444                  */
 445
 446
 447                 /* get the PCI Base Address Registers */
 448                 brd->membase = pci_resource_start(pdev, 4);
 449
 450                 if (!brd->membase) {
 451                         dev_err(&brd->pdev->dev,
 452                                 "Card has no PCI IO resources, failing.\n");
 453                         return -ENODEV;
 454                 }
 455
 456                 brd->membase_end = pci_resource_end(pdev, 4);
 457
 458                 if (brd->membase & 1)
 459                         brd->membase &= ~3;
 460                 else
 461                         brd->membase &= ~15;
 462
 463                 brd->iobase     = pci_resource_start(pdev, 1);
 464                 brd->iobase_end = pci_resource_end(pdev, 1);
 465                 brd->iobase     = ((unsigned int) (brd->iobase)) & 0xFFFE;
 466
 467                 /* Assign the board_ops struct */
 468                 brd->bd_ops = &dgnc_cls_ops;
 469
 470                 brd->bd_uart_offset = 0x8;
 471                 brd->bd_dividend = 921600;
 472
 473                 dgnc_do_remap(brd);
 474
 475                 /* Get and store the board VPD, if it exists */
 476                 brd->bd_ops->vpd(brd);
 477
 478                 /*
 479                  * Enable Local Interrupt 1               (0x1),
 480                  * Local Interrupt 1 Polarity Active high (0x2),
 481                  * Enable PCI interrupt                   (0x40)
 482                  */
 483                 outb(0x43, brd->iobase + 0x4c);
 484
 485                 break;
 486
 487
 488         case PCI_DEVICE_NEO_4_DID:
 489         case PCI_DEVICE_NEO_8_DID:
 490         case PCI_DEVICE_NEO_2DB9_DID:
 491         case PCI_DEVICE_NEO_2DB9PRI_DID:
 492         case PCI_DEVICE_NEO_2RJ45_DID:
 493         case PCI_DEVICE_NEO_2RJ45PRI_DID:
 494         case PCI_DEVICE_NEO_1_422_DID:
 495         case PCI_DEVICE_NEO_1_422_485_DID:
 496         case PCI_DEVICE_NEO_2_422_485_DID:
 497         case PCI_DEVICE_NEO_EXPRESS_8_DID:
 498         case PCI_DEVICE_NEO_EXPRESS_4_DID:
 499         case PCI_DEVICE_NEO_EXPRESS_4RJ45_DID:
 500         case PCI_DEVICE_NEO_EXPRESS_8RJ45_DID:
 501
 502                 /*
 503                  * This chip is set up 100% when we get to it.
 504                  * No need to enable global interrupts or anything.
 505                  */
 506                 if (brd->bd_flags & BD_IS_PCI_EXPRESS)
 507                         brd->dpatype = T_NEO_EXPRESS | T_PCIBUS;
 508                 else
 509                         brd->dpatype = T_NEO | T_PCIBUS;
 510
 511                 /* get the PCI Base Address Registers */
 512                 brd->membase     = pci_resource_start(pdev, 0);
 513                 brd->membase_end = pci_resource_end(pdev, 0);
 514
 515                 if (brd->membase & 1)
 516                         brd->membase &= ~3;
 517                 else
 518                         brd->membase &= ~15;
 519
 520                 /* Assign the board_ops struct */
 521                 brd->bd_ops = &dgnc_neo_ops;
 522
 523                 brd->bd_uart_offset = 0x200;
 524                 brd->bd_dividend = 921600;
 525
 526                 dgnc_do_remap(brd);
 527
 528                 if (brd->re_map_membase) {
 529
 530                         /* Read and store the dvid after remapping */
 531                         brd->dvid = readb(brd->re_map_membase + 0x8D);
 532
 533                         /* Get and store the board VPD, if it exists */
 534                         brd->bd_ops->vpd(brd);
 535                 }
 536                 break;
 537
 538         default:
 539                 dev_err(&brd->pdev->dev,
 540                         "Didn't find any compatible Neo/Classic PCI boards.\n");
 541                 return -ENXIO;
 542
 543         }
 544
 545         /*
 546          * Do tty device initialization.
 547          */
 548
 549         rc = dgnc_tty_register(brd);
 550         if (rc < 0) {
 551                 pr_err(DRVSTR ": Can't register tty devices (%d)\n", rc);
 552                 goto failed;
 553         }
 554
 555         rc = dgnc_finalize_board_init(brd);
 556         if (rc < 0) {
 557                 pr_err(DRVSTR ": Can't finalize board init (%d)\n", rc);
 558                 goto failed;
 559         }
 560
 561         rc = dgnc_tty_init(brd);
 562         if (rc < 0) {
 563                 pr_err(DRVSTR ": Can't init tty devices (%d)\n", rc);
 564                 goto failed;
 565         }
 566
 567         brd->state = BOARD_READY;
 568         brd->dpastatus = BD_RUNNING;
 569
 570         dgnc_create_ports_sysfiles(brd);
 571
 572         /* init our poll helper tasklet */
 573         tasklet_init(&brd->helper_tasklet,
 574                      brd->bd_ops->tasklet,
 575                      (unsigned long) brd);
 576
 577         spin_lock_irqsave(&dgnc_global_lock, flags);
 578         brd->msgbuf = NULL;
 579         dev_dbg(&brd->pdev->dev, "%s\n", brd->msgbuf_head);
 580         kfree(brd->msgbuf_head);
 581         brd->msgbuf_head = NULL;
 582         spin_unlock_irqrestore(&dgnc_global_lock, flags);
 583
 584         /*
 585          * allocate flip buffer for board.
 586          *
 587          * Okay to malloc with GFP_KERNEL, we are not at interrupt
 588          * context, and there are no locks held.
 589          */
 590         brd->flipbuf = kzalloc(MYFLIPLEN, GFP_KERNEL);
 591
 592         wake_up_interruptible(&brd->state_wait);
 593
 594         return 0;
 595
 596 failed:
 597         dgnc_tty_uninit(brd);
 598         brd->state = BOARD_FAILED;
 599         brd->dpastatus = BD_NOFEP;
 600
 601         return -ENXIO;
 602
 603 }
 604
 605
 606 static int dgnc_finalize_board_init(struct dgnc_board *brd)
 607 {
 608         int rc = 0;
 609
 610         if (!brd || brd->magic != DGNC_BOARD_MAGIC)
 611                 return -ENODEV;
 612
 613         if (brd->irq) {
 614                 rc = request_irq(brd->irq, brd->bd_ops->intr,
 615                                  IRQF_SHARED, "DGNC", brd);
 616
 617                 if (rc) {
 618                         dev_err(&brd->pdev->dev,
 619                                 "Failed to hook IRQ %d\n", brd->irq);
 620                         brd->state = BOARD_FAILED;
 621                         brd->dpastatus = BD_NOFEP;
 622                         rc = -ENODEV;
 623                 }
 624         }
 625         return rc;
 626 }
 627
 628 /*
 629  * Remap PCI memory.
 630  */
 631 static void dgnc_do_remap(struct dgnc_board *brd)
 632 {
 633
 634         if (!brd || brd->magic != DGNC_BOARD_MAGIC)
 635                 return;
 636
 637         brd->re_map_membase = ioremap(brd->membase, 0x1000);
 638 }
 639
 640
 641 /*****************************************************************************
 642 *
 643 * Function:
 644 *
 645 *    dgnc_poll_handler
 646 *
 647 * Author:
 648 *
 649 *    Scott H Kilau
 650 *
 651 * Parameters:
 652 *
 653 *    dummy -- ignored
 654 *
 655 * Return Values:
 656 *
 657 *    none
 658 *
 659 * Description:
 660 *
 661 *    As each timer expires, it determines (a) whether the "transmit"
 662 *    waiter needs to be woken up, and (b) whether the poller needs to
 663 *    be rescheduled.
 664 *
 665 ******************************************************************************/
 666
 667 static void dgnc_poll_handler(ulong dummy)
 668 {
 669         struct dgnc_board *brd;
 670         unsigned long flags;
 671         int i;
 672         unsigned long new_time;
 673
 674         /* Go thru each board, kicking off a tasklet for each if needed */
 675         for (i = 0; i < dgnc_NumBoards; i++) {
 676                 brd = dgnc_Board[i];
 677
 678                 spin_lock_irqsave(&brd->bd_lock, flags);
 679
 680                 /* If board is in a failed state don't schedule a tasklet */
 681                 if (brd->state == BOARD_FAILED) {
 682                         spin_unlock_irqrestore(&brd->bd_lock, flags);
 683                         continue;
 684                 }
 685
 686                 /* Schedule a poll helper task */
 687                 tasklet_schedule(&brd->helper_tasklet);
 688
 689                 spin_unlock_irqrestore(&brd->bd_lock, flags);
 690         }
 691
 692         /*
 693          * Schedule ourself back at the nominal wakeup interval.
 694          */
 695         spin_lock_irqsave(&dgnc_poll_lock, flags);
 696         dgnc_poll_time += dgnc_jiffies_from_ms(dgnc_poll_tick);
 697
 698         new_time = dgnc_poll_time - jiffies;
 699
 700         if ((ulong) new_time >= 2 * dgnc_poll_tick)
 701                 dgnc_poll_time = jiffies + dgnc_jiffies_from_ms(dgnc_poll_tick);
 702
 703         setup_timer(&dgnc_poll_timer, dgnc_poll_handler, 0);
 704         dgnc_poll_timer.expires = dgnc_poll_time;
 705         spin_unlock_irqrestore(&dgnc_poll_lock, flags);
 706
 707         if (!dgnc_poll_stop)
 708                 add_timer(&dgnc_poll_timer);
 709 }
 710
 711 /*
 712  * dgnc_init_globals()
 713  *
 714  * This is where we initialize the globals from the static insmod
 715  * configuration variables.  These are declared near the head of
 716  * this file.
 717  */
 718 static void dgnc_init_globals(void)
 719 {
 720         int i = 0;
 721
 722         dgnc_NumBoards          = 0;
 723
 724         for (i = 0; i < MAXBOARDS; i++)
 725                 dgnc_Board[i] = NULL;
 726
 727         init_timer(&dgnc_poll_timer);
 728 }
 729