drivers/char/watchdog/pcwd_usb.c

   1 /*
   2  *      Berkshire USB-PC Watchdog Card Driver
   3  *
   4  *      (c) Copyright 2004 Wim Van Sebroeck <wim@iguana.be>.
   5  *
   6  *      Based on source code of the following authors:
   7  *        Ken Hollis <kenji@bitgate.com>,
   8  *        Alan Cox <alan@redhat.com>,
   9  *        Matt Domsch <Matt_Domsch@dell.com>,
  10  *        Rob Radez <rob@osinvestor.com>,
  11  *        Greg Kroah-Hartman <greg@kroah.com>
  12  *
  13  *      This program is free software; you can redistribute it and/or
  14  *      modify it under the terms of the GNU General Public License
  15  *      as published by the Free Software Foundation; either version
  16  *      2 of the License, or (at your option) any later version.
  17  *
  18  *      Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
  19  *      provide warranty for any of this software. This material is
  20  *      provided "AS-IS" and at no charge.
  21  *
  22  *      Thanks also to Simon Machell at Berkshire Products Inc. for
  23  *      providing the test hardware. More info is available at
  24  *      http://www.berkprod.com/ or http://www.pcwatchdog.com/
  25  */
  26
  27 #include <linux/config.h>
  28 #include <linux/kernel.h>
  29 #include <linux/errno.h>
  30 #include <linux/init.h>
  31 #include <linux/slab.h>
  32 #include <linux/module.h>
  33 #include <linux/moduleparam.h>
  34 #include <linux/types.h>
  35 #include <linux/delay.h>
  36 #include <linux/miscdevice.h>
  37 #include <linux/watchdog.h>
  38 #include <linux/notifier.h>
  39 #include <linux/reboot.h>
  40 #include <linux/fs.h>
  41 #include <linux/smp_lock.h>
  42 #include <linux/completion.h>
  43 #include <asm/uaccess.h>
  44 #include <linux/usb.h>
  45
  46
  47 #ifdef CONFIG_USB_DEBUG
  48         static int debug = 1;
  49 #else
  50         static int debug;
  51 #endif
  52
  53 /* Use our own dbg macro */
  54 #undef dbg
  55 #define dbg(format, arg...) do { if (debug) printk(KERN_DEBUG PFX format "\n" , ## arg); } while (0)
  56
  57
  58 /* Module and Version Information */
  59 #define DRIVER_VERSION "v1.00 (28/02/2004)"
  60 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
  61 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
  62 #define DRIVER_LICENSE "GPL"
  63 #define DRIVER_NAME "pcwd_usb"
  64 #define PFX DRIVER_NAME ": "
  65
  66 MODULE_AUTHOR(DRIVER_AUTHOR);
  67 MODULE_DESCRIPTION(DRIVER_DESC);
  68 MODULE_LICENSE(DRIVER_LICENSE);
  69 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
  70 MODULE_ALIAS_MISCDEV(TEMP_MINOR);
  71
  72 /* Module Parameters */
  73 module_param(debug, int, 0);
  74 MODULE_PARM_DESC(debug, "Debug enabled or not");
  75
  76 #define WATCHDOG_HEARTBEAT 2    /* 2 sec default heartbeat */
  77 static int heartbeat = WATCHDOG_HEARTBEAT;
  78 module_param(heartbeat, int, 0);
  79 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (0<heartbeat<65536, default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
  80
  81 #ifdef CONFIG_WATCHDOG_NOWAYOUT
  82 static int nowayout = 1;
  83 #else
  84 static int nowayout = 0;
  85 #endif
  86
  87 module_param(nowayout, int, 0);
  88 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
  89
  90 /* The vendor and product id's for the USB-PC Watchdog card */
  91 #define USB_PCWD_VENDOR_ID      0x0c98
  92 #define USB_PCWD_PRODUCT_ID     0x1140
  93
  94 /* table of devices that work with this driver */
  95 static struct usb_device_id usb_pcwd_table [] = {
  96         { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
  97         { }                                     /* Terminating entry */
  98 };
  99 MODULE_DEVICE_TABLE (usb, usb_pcwd_table);
 100
 101 /* according to documentation max. time to process a command for the USB
 102  * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
 103 #define USB_COMMAND_TIMEOUT     250
 104
 105 /* Watchdog's internal commands */
 106 #define CMD_READ_TEMP                   0x02    /* Read Temperature; Re-trigger Watchdog */
 107 #define CMD_TRIGGER                     CMD_READ_TEMP
 108 #define CMD_GET_STATUS                  0x04    /* Get Status Information */
 109 #define CMD_GET_FIRMWARE_VERSION        0x08    /* Get Firmware Version */
 110 #define CMD_GET_DIP_SWITCH_SETTINGS     0x0c    /* Get Dip Switch Settings */
 111 #define CMD_READ_WATCHDOG_TIMEOUT       0x18    /* Read Current Watchdog Time */
 112 #define CMD_WRITE_WATCHDOG_TIMEOUT      0x19    /* Write Current Watchdog Time */
 113 #define CMD_ENABLE_WATCHDOG             0x30    /* Enable / Disable Watchdog */
 114 #define CMD_DISABLE_WATCHDOG            CMD_ENABLE_WATCHDOG
 115
 116 /* Some defines that I like to be somewhere else like include/linux/usb_hid.h */
 117 #define HID_REQ_SET_REPORT              0x09
 118 #define HID_DT_REPORT                   (USB_TYPE_CLASS | 0x02)
 119
 120 /* We can only use 1 card due to the /dev/watchdog restriction */
 121 static int cards_found;
 122
 123 /* some internal variables */
 124 static unsigned long is_active;
 125 static char expect_release;
 126
 127 /* Structure to hold all of our device specific stuff */
 128 struct usb_pcwd_private {
 129         struct usb_device *     udev;                   /* save off the usb device pointer */
 130         struct usb_interface *  interface;              /* the interface for this device */
 131
 132         unsigned int            interface_number;       /* the interface number used for cmd's */
 133
 134         unsigned char *         intr_buffer;            /* the buffer to intr data */
 135         dma_addr_t              intr_dma;               /* the dma address for the intr buffer */
 136         size_t                  intr_size;              /* the size of the intr buffer */
 137         struct urb *            intr_urb;               /* the urb used for the intr pipe */
 138
 139         unsigned char           cmd_command;            /* The command that is reported back */
 140         unsigned char           cmd_data_msb;           /* The data MSB that is reported back */
 141         unsigned char           cmd_data_lsb;           /* The data LSB that is reported back */
 142         atomic_t                cmd_received;           /* true if we received a report after a command */
 143
 144         int                     exists;                 /* Wether or not the device exists */
 145         struct semaphore        sem;                    /* locks this structure */
 146 };
 147 static struct usb_pcwd_private *usb_pcwd_device;
 148
 149 /* prevent races between open() and disconnect() */
 150 static DECLARE_MUTEX (disconnect_sem);
 151
 152 /* local function prototypes */
 153 static int usb_pcwd_probe       (struct usb_interface *interface, const struct usb_device_id *id);
 154 static void usb_pcwd_disconnect (struct usb_interface *interface);
 155
 156 /* usb specific object needed to register this driver with the usb subsystem */
 157 static struct usb_driver usb_pcwd_driver = {
 158         .owner =        THIS_MODULE,
 159         .name =         DRIVER_NAME,
 160         .probe =        usb_pcwd_probe,
 161         .disconnect =   usb_pcwd_disconnect,
 162         .id_table =     usb_pcwd_table,
 163 };
 164
 165
 166 static void usb_pcwd_intr_done(struct urb *urb, struct pt_regs *regs)
 167 {
 168         struct usb_pcwd_private *usb_pcwd = (struct usb_pcwd_private *)urb->context;
 169         unsigned char *data = usb_pcwd->intr_buffer;
 170         int retval;
 171
 172         switch (urb->status) {
 173         case 0:                 /* success */
 174                 break;
 175         case -ECONNRESET:       /* unlink */
 176         case -ENOENT:
 177         case -ESHUTDOWN:
 178                 /* this urb is terminated, clean up */
 179                 dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
 180                 return;
 181         /* -EPIPE:  should clear the halt */
 182         default:                /* error */
 183                 dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
 184                 goto resubmit;
 185         }
 186
 187         dbg("received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
 188                 data[0], data[1], data[2]);
 189
 190         usb_pcwd->cmd_command  = data[0];
 191         usb_pcwd->cmd_data_msb = data[1];
 192         usb_pcwd->cmd_data_lsb = data[2];
 193
 194         /* notify anyone waiting that the cmd has finished */
 195         atomic_set (&usb_pcwd->cmd_received, 1);
 196
 197 resubmit:
 198         retval = usb_submit_urb (urb, GFP_ATOMIC);
 199         if (retval)
 200                 printk(KERN_ERR PFX "can't resubmit intr, usb_submit_urb failed with result %d\n",
 201                         retval);
 202 }
 203
 204 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd, unsigned char cmd,
 205         unsigned char *msb, unsigned char *lsb)
 206 {
 207         int got_response, count;
 208         unsigned char buf[6];
 209
 210         /* We will not send any commands if the USB PCWD device does not exist */
 211         if ((!usb_pcwd) || (!usb_pcwd->exists))
 212                 return -1;
 213
 214         /* The USB PC Watchdog uses a 6 byte report format. The board currently uses
 215          * only 3 of the six bytes of the report. */
 216         buf[0] = cmd;                   /* Byte 0 = CMD */
 217         buf[1] = *msb;                  /* Byte 1 = Data MSB */
 218         buf[2] = *lsb;                  /* Byte 2 = Data LSB */
 219         buf[3] = buf[4] = buf[5] = 0;   /* All other bytes not used */
 220
 221         dbg("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
 222                 buf[0], buf[1], buf[2]);
 223
 224         atomic_set (&usb_pcwd->cmd_received, 0);
 225
 226         if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
 227                         HID_REQ_SET_REPORT, HID_DT_REPORT,
 228                         0x0200, usb_pcwd->interface_number, buf, sizeof(buf),
 229                         HZ) != sizeof(buf)) {
 230                 dbg("usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n", cmd, *msb, *lsb);
 231         }
 232         /* wait till the usb card processed the command,
 233          * with a max. timeout of USB_COMMAND_TIMEOUT */
 234         got_response = 0;
 235         for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response); count++) {
 236                 mdelay(1);
 237                 if (atomic_read (&usb_pcwd->cmd_received))
 238                         got_response = 1;
 239         }
 240
 241         if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
 242                 /* read back response */
 243                 *msb = usb_pcwd->cmd_data_msb;
 244                 *lsb = usb_pcwd->cmd_data_lsb;
 245         }
 246
 247         return got_response;
 248 }
 249
 250 static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
 251 {
 252         unsigned char msb = 0x00;
 253         unsigned char lsb = 0x00;
 254         int retval;
 255
 256         /* Enable Watchdog */
 257         retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG, &msb, &lsb);
 258
 259         if ((retval == 0) || (lsb == 0)) {
 260                 printk(KERN_ERR PFX "Card did not acknowledge enable attempt\n");
 261                 return -1;
 262         }
 263
 264         return 0;
 265 }
 266
 267 static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
 268 {
 269         unsigned char msb = 0xA5;
 270         unsigned char lsb = 0xC3;
 271         int retval;
 272
 273         /* Disable Watchdog */
 274         retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG, &msb, &lsb);
 275
 276         if ((retval == 0) || (lsb != 0)) {
 277                 printk(KERN_ERR PFX "Card did not acknowledge disable attempt\n");
 278                 return -1;
 279         }
 280
 281         return 0;
 282 }
 283
 284 static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
 285 {
 286         unsigned char dummy;
 287
 288         /* Re-trigger Watchdog */
 289         usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
 290
 291         return 0;
 292 }
 293
 294 static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
 295 {
 296         unsigned char msb = t / 256;
 297         unsigned char lsb = t % 256;
 298
 299         if ((t < 0x0001) || (t > 0xFFFF))
 300                 return -EINVAL;
 301
 302         /* Write new heartbeat to watchdog */
 303         usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
 304
 305         heartbeat = t;
 306         return 0;
 307 }
 308
 309 static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, int *temperature)
 310 {
 311         unsigned char msb, lsb;
 312
 313         usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
 314
 315         /*
 316          * Convert celsius to fahrenheit, since this was
 317          * the decided 'standard' for this return value.
 318          */
 319         *temperature = (lsb * 9 / 5) + 32;
 320
 321         return 0;
 322 }
 323
 324 /*
 325  *      /dev/watchdog handling
 326  */
 327
 328 static ssize_t usb_pcwd_write(struct file *file, const char *data,
 329                               size_t len, loff_t *ppos)
 330 {
 331         /* Can't seek (pwrite) on this device  */
 332         if (ppos != &file->f_pos)
 333                 return -ESPIPE;
 334
 335         /* See if we got the magic character 'V' and reload the timer */
 336         if (len) {
 337                 if (!nowayout) {
 338                         size_t i;
 339
 340                         /* note: just in case someone wrote the magic character
 341                          * five months ago... */
 342                         expect_release = 0;
 343
 344                         /* scan to see whether or not we got the magic character */
 345                         for (i = 0; i != len; i++) {
 346                                 char c;
 347                                 if(get_user(c, data+i))
 348                                         return -EFAULT;
 349                                 if (c == 'V')
 350                                         expect_release = 42;
 351                         }
 352                 }
 353
 354                 /* someone wrote to us, we should reload the timer */
 355                 usb_pcwd_keepalive(usb_pcwd_device);
 356         }
 357         return len;
 358 }
 359
 360 static int usb_pcwd_ioctl(struct inode *inode, struct file *file,
 361                           unsigned int cmd, unsigned long arg)
 362 {
 363         static struct watchdog_info ident = {
 364                 .options =              WDIOF_KEEPALIVEPING |
 365                                         WDIOF_SETTIMEOUT |
 366                                         WDIOF_MAGICCLOSE,
 367                 .firmware_version =     1,
 368                 .identity =             DRIVER_NAME,
 369         };
 370
 371         switch (cmd) {
 372                 case WDIOC_GETSUPPORT:
 373                         return copy_to_user((struct watchdog_info *) arg, &ident,
 374                                 sizeof (ident)) ? -EFAULT : 0;
 375
 376                 case WDIOC_GETSTATUS:
 377                 case WDIOC_GETBOOTSTATUS:
 378                         return put_user(0, (int *) arg);
 379
 380                 case WDIOC_GETTEMP:
 381                 {
 382                         int temperature;
 383
 384                         if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
 385                                 return -EFAULT;
 386
 387                         return put_user(temperature, (int *) arg);
 388                 }
 389
 390                 case WDIOC_KEEPALIVE:
 391                         usb_pcwd_keepalive(usb_pcwd_device);
 392                         return 0;
 393
 394                 case WDIOC_SETOPTIONS:
 395                 {
 396                         int new_options, retval = -EINVAL;
 397
 398                         if (get_user (new_options, (int *) arg))
 399                                 return -EFAULT;
 400
 401                         if (new_options & WDIOS_DISABLECARD) {
 402                                 usb_pcwd_stop(usb_pcwd_device);
 403                                 retval = 0;
 404                         }
 405
 406                         if (new_options & WDIOS_ENABLECARD) {
 407                                 usb_pcwd_start(usb_pcwd_device);
 408                                 retval = 0;
 409                         }
 410
 411                         return retval;
 412                 }
 413
 414                 case WDIOC_SETTIMEOUT:
 415                 {
 416                         int new_heartbeat;
 417
 418                         if (get_user(new_heartbeat, (int *) arg))
 419                                 return -EFAULT;
 420
 421                         if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
 422                             return -EINVAL;
 423
 424                         usb_pcwd_keepalive(usb_pcwd_device);
 425                         /* Fall */
 426                 }
 427
 428                 case WDIOC_GETTIMEOUT:
 429                         return put_user(heartbeat, (int *)arg);
 430
 431                 default:
 432                         return -ENOIOCTLCMD;
 433         }
 434 }
 435
 436 static int usb_pcwd_open(struct inode *inode, struct file *file)
 437 {
 438         /* /dev/watchdog can only be opened once */
 439         if (test_and_set_bit(0, &is_active))
 440                 return -EBUSY;
 441
 442         /* Activate */
 443         usb_pcwd_start(usb_pcwd_device);
 444         usb_pcwd_keepalive(usb_pcwd_device);
 445         return 0;
 446 }
 447
 448 static int usb_pcwd_release(struct inode *inode, struct file *file)
 449 {
 450         /*
 451          *      Shut off the timer.
 452          */
 453         if (expect_release == 42) {
 454                 usb_pcwd_stop(usb_pcwd_device);
 455         } else {
 456                 printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
 457                 usb_pcwd_keepalive(usb_pcwd_device);
 458         }
 459         clear_bit(0, &is_active);
 460         expect_release = 0;
 461         return 0;
 462 }
 463
 464 /*
 465  *      /dev/temperature handling
 466  */
 467
 468 static ssize_t usb_pcwd_temperature_read(struct file *file, char *data,
 469                                 size_t len, loff_t *ppos)
 470 {
 471         int temperature;
 472
 473         /* Can't seek (pwrite) on this device  */
 474         if (ppos != &file->f_pos)
 475                 return -ESPIPE;
 476
 477         if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
 478                 return -EFAULT;
 479
 480         if (copy_to_user (data, &temperature, 1))
 481                 return -EFAULT;
 482
 483         return 1;
 484 }
 485
 486 static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
 487 {
 488         return 0;
 489 }
 490
 491 static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
 492 {
 493         return 0;
 494 }
 495
 496 /*
 497  *      Notify system
 498  */
 499
 500 static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
 501 {
 502         if (code==SYS_DOWN || code==SYS_HALT) {
 503                 /* Turn the WDT off */
 504                 usb_pcwd_stop(usb_pcwd_device);
 505         }
 506
 507         return NOTIFY_DONE;
 508 }
 509
 510 /*
 511  *      Kernel Interfaces
 512  */
 513
 514 static struct file_operations usb_pcwd_fops = {
 515         .owner =        THIS_MODULE,
 516         .llseek =       no_llseek,
 517         .write =        usb_pcwd_write,
 518         .ioctl =        usb_pcwd_ioctl,
 519         .open =         usb_pcwd_open,
 520         .release =      usb_pcwd_release,
 521 };
 522
 523 static struct miscdevice usb_pcwd_miscdev = {
 524         .minor =        WATCHDOG_MINOR,
 525         .name =         "watchdog",
 526         .fops =         &usb_pcwd_fops,
 527 };
 528
 529 static struct file_operations usb_pcwd_temperature_fops = {
 530         .owner =        THIS_MODULE,
 531         .llseek =       no_llseek,
 532         .read =         usb_pcwd_temperature_read,
 533         .open =         usb_pcwd_temperature_open,
 534         .release =      usb_pcwd_temperature_release,
 535 };
 536
 537 static struct miscdevice usb_pcwd_temperature_miscdev = {
 538         .minor =        TEMP_MINOR,
 539         .name =         "temperature",
 540         .fops =         &usb_pcwd_temperature_fops,
 541 };
 542
 543 static struct notifier_block usb_pcwd_notifier = {
 544         .notifier_call =        usb_pcwd_notify_sys,
 545 };
 546
 547 /**
 548  *      usb_pcwd_delete
 549  */
 550 static inline void usb_pcwd_delete (struct usb_pcwd_private *usb_pcwd)
 551 {
 552         if (usb_pcwd->intr_urb != NULL)
 553                 usb_free_urb (usb_pcwd->intr_urb);
 554         if (usb_pcwd->intr_buffer != NULL)
 555                 usb_buffer_free(usb_pcwd->udev, usb_pcwd->intr_size,
 556                                 usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
 557         kfree (usb_pcwd);
 558 }
 559
 560 /**
 561  *      usb_pcwd_probe
 562  *
 563  *      Called by the usb core when a new device is connected that it thinks
 564  *      this driver might be interested in.
 565  */
 566 static int usb_pcwd_probe(struct usb_interface *interface, const struct usb_device_id *id)
 567 {
 568         struct usb_device *udev = interface_to_usbdev(interface);
 569         struct usb_host_interface *iface_desc;
 570         struct usb_endpoint_descriptor *endpoint;
 571         struct usb_pcwd_private *usb_pcwd = NULL;
 572         int pipe, maxp;
 573         int retval = -ENOMEM;
 574         int got_fw_rev;
 575         unsigned char fw_rev_major, fw_rev_minor;
 576         char fw_ver_str[20];
 577         unsigned char option_switches, dummy;
 578
 579         /* See if the device offered us matches what we can accept */
 580         if ((udev->descriptor.idVendor != USB_PCWD_VENDOR_ID) ||
 581             (udev->descriptor.idProduct != USB_PCWD_PRODUCT_ID)) {
 582                 return -ENODEV;
 583         }
 584
 585         cards_found++;
 586         if (cards_found > 1) {
 587                 printk(KERN_ERR PFX "This driver only supports 1 device\n");
 588                 return -ENODEV;
 589         }
 590
 591         /* get the active interface descriptor */
 592         iface_desc = interface->cur_altsetting;
 593
 594         /* check out that we have a HID device */
 595         if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
 596                 printk(KERN_ERR PFX "The device isn't a Human Interface Device\n");
 597                 return -ENODEV;
 598         }
 599
 600         /* check out the endpoint: it has to be Interrupt & IN */
 601         endpoint = &iface_desc->endpoint[0].desc;
 602
 603         if (!((endpoint->bEndpointAddress & USB_DIR_IN) &&
 604              ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 605                                 == USB_ENDPOINT_XFER_INT))) {
 606                 /* we didn't find a Interrupt endpoint with direction IN */
 607                 printk(KERN_ERR PFX "Couldn't find an INTR & IN endpoint\n");
 608                 return -ENODEV;
 609         }
 610
 611         /* get a handle to the interrupt data pipe */
 612         pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
 613         maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
 614
 615         /* allocate memory for our device and initialize it */
 616         usb_pcwd = kmalloc (sizeof(struct usb_pcwd_private), GFP_KERNEL);
 617         if (usb_pcwd == NULL) {
 618                 printk(KERN_ERR PFX "Out of memory\n");
 619                 goto error;
 620         }
 621         memset (usb_pcwd, 0x00, sizeof (*usb_pcwd));
 622
 623         usb_pcwd_device = usb_pcwd;
 624
 625         init_MUTEX (&usb_pcwd->sem);
 626         usb_pcwd->udev = udev;
 627         usb_pcwd->interface = interface;
 628         usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
 629         usb_pcwd->intr_size = (endpoint->wMaxPacketSize > 8 ? endpoint->wMaxPacketSize : 8);
 630
 631         /* set up the memory buffer's */
 632         if (!(usb_pcwd->intr_buffer = usb_buffer_alloc(udev, usb_pcwd->intr_size, SLAB_ATOMIC, &usb_pcwd->intr_dma))) {
 633                 printk(KERN_ERR PFX "Out of memory\n");
 634                 goto error;
 635         }
 636
 637         /* allocate the urb's */
 638         usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
 639         if (!usb_pcwd->intr_urb) {
 640                 printk(KERN_ERR PFX "Out of memory\n");
 641                 goto error;
 642         }
 643
 644         /* initialise the intr urb's */
 645         usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
 646                         usb_pcwd->intr_buffer, usb_pcwd->intr_size,
 647                         usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
 648         usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
 649         usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 650
 651         /* register our interrupt URB with the USB system */
 652         if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
 653                 printk(KERN_ERR PFX "Problem registering interrupt URB\n");
 654                 retval = -EIO; /* failure */
 655                 goto error;
 656         }
 657
 658         /* The device exists and can be communicated with */
 659         usb_pcwd->exists = 1;
 660
 661         /* disable card */
 662         usb_pcwd_stop(usb_pcwd);
 663
 664         /* Get the Firmware Version */
 665         got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION, &fw_rev_major, &fw_rev_minor);
 666         if (got_fw_rev) {
 667                 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
 668         } else {
 669                 sprintf(fw_ver_str, "<card no answer>");
 670         }
 671
 672         printk(KERN_INFO PFX "Found card (Firmware: %s) with temp option\n",
 673                 fw_ver_str);
 674
 675         /* Get switch settings */
 676         usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy, &option_switches);
 677
 678         printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
 679                 option_switches,
 680                 ((option_switches & 0x10) ? "ON" : "OFF"),
 681                 ((option_switches & 0x08) ? "ON" : "OFF"));
 682
 683         /* Check that the heartbeat value is within it's range ; if not reset to the default */
 684         if (heartbeat < 1 || heartbeat > 0xFFFF) {
 685                 heartbeat = WATCHDOG_HEARTBEAT;
 686                 printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
 687                         heartbeat);
 688         }
 689
 690         /* Calculate the watchdog's heartbeat */
 691         usb_pcwd_set_heartbeat(usb_pcwd, heartbeat);
 692
 693         retval = register_reboot_notifier(&usb_pcwd_notifier);
 694         if (retval != 0) {
 695                 printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
 696                         retval);
 697                 goto error;
 698         }
 699
 700         retval = misc_register(&usb_pcwd_miscdev);
 701         if (retval != 0) {
 702                 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
 703                         WATCHDOG_MINOR, retval);
 704                 goto err_out_unregister_reboot;
 705         }
 706
 707         retval = misc_register(&usb_pcwd_temperature_miscdev);
 708         if (retval != 0) {
 709                 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
 710                         TEMP_MINOR, retval);
 711                 goto err_out_misc_deregister;
 712         }
 713
 714         /* we can register the device now, as it is ready */
 715         usb_set_intfdata (interface, usb_pcwd);
 716
 717         printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
 718                 heartbeat, nowayout);
 719
 720         return 0;
 721
 722 err_out_misc_deregister:
 723         misc_deregister(&usb_pcwd_miscdev);
 724 err_out_unregister_reboot:
 725         unregister_reboot_notifier(&usb_pcwd_notifier);
 726 error:
 727         usb_pcwd_delete (usb_pcwd);
 728         usb_pcwd_device = NULL;
 729         return retval;
 730 }
 731
 732
 733 /**
 734  *      usb_pcwd_disconnect
 735  *
 736  *      Called by the usb core when the device is removed from the system.
 737  *
 738  *      This routine guarantees that the driver will not submit any more urbs
 739  *      by clearing dev->udev.
 740  */
 741 static void usb_pcwd_disconnect(struct usb_interface *interface)
 742 {
 743         struct usb_pcwd_private *usb_pcwd;
 744
 745         /* prevent races with open() */
 746         down (&disconnect_sem);
 747
 748         usb_pcwd = usb_get_intfdata (interface);
 749         usb_set_intfdata (interface, NULL);
 750
 751         down (&usb_pcwd->sem);
 752
 753         /* Stop the timer before we leave */
 754         if (!nowayout)
 755                 usb_pcwd_stop(usb_pcwd);
 756
 757         /* We should now stop communicating with the USB PCWD device */
 758         usb_pcwd->exists = 0;
 759
 760         /* Deregister */
 761         misc_deregister(&usb_pcwd_temperature_miscdev);
 762         misc_deregister(&usb_pcwd_miscdev);
 763         unregister_reboot_notifier(&usb_pcwd_notifier);
 764
 765         up (&usb_pcwd->sem);
 766
 767         /* Delete the USB PCWD device */
 768         usb_pcwd_delete(usb_pcwd);
 769
 770         cards_found--;
 771
 772         up (&disconnect_sem);
 773
 774         printk(KERN_INFO PFX "USB PC Watchdog disconnected\n");
 775 }
 776
 777
 778
 779 /**
 780  *      usb_pcwd_init
 781  */
 782 static int __init usb_pcwd_init(void)
 783 {
 784         int result;
 785
 786         /* register this driver with the USB subsystem */
 787         result = usb_register(&usb_pcwd_driver);
 788         if (result) {
 789                 printk(KERN_ERR PFX "usb_register failed. Error number %d\n",
 790                     result);
 791                 return result;
 792         }
 793
 794         printk(KERN_INFO PFX DRIVER_DESC " " DRIVER_VERSION "\n");
 795         return 0;
 796 }
 797
 798
 799 /**
 800  *      usb_pcwd_exit
 801  */
 802 static void __exit usb_pcwd_exit(void)
 803 {
 804         /* deregister this driver with the USB subsystem */
 805         usb_deregister(&usb_pcwd_driver);
 806 }
 807
 808
 809 module_init (usb_pcwd_init);
 810 module_exit (usb_pcwd_exit);