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 "1.00"
  60 #define DRIVER_DATE "12 Jun 2004"
  61 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
  62 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
  63 #define DRIVER_LICENSE "GPL"
  64 #define DRIVER_NAME "pcwd_usb"
  65 #define PFX DRIVER_NAME ": "
  66
  67 MODULE_AUTHOR(DRIVER_AUTHOR);
  68 MODULE_DESCRIPTION(DRIVER_DESC);
  69 MODULE_LICENSE(DRIVER_LICENSE);
  70 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
  71 MODULE_ALIAS_MISCDEV(TEMP_MINOR);
  72
  73 /* Module Parameters */
  74 module_param(debug, int, 0);
  75 MODULE_PARM_DESC(debug, "Debug enabled or not");
  76
  77 #define WATCHDOG_HEARTBEAT 2    /* 2 sec default heartbeat */
  78 static int heartbeat = WATCHDOG_HEARTBEAT;
  79 module_param(heartbeat, int, 0);
  80 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (0<heartbeat<65536, default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
  81
  82 #ifdef CONFIG_WATCHDOG_NOWAYOUT
  83 static int nowayout = 1;
  84 #else
  85 static int nowayout = 0;
  86 #endif
  87
  88 module_param(nowayout, int, 0);
  89 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
  90
  91 /* The vendor and product id's for the USB-PC Watchdog card */
  92 #define USB_PCWD_VENDOR_ID      0x0c98
  93 #define USB_PCWD_PRODUCT_ID     0x1140
  94
  95 /* table of devices that work with this driver */
  96 static struct usb_device_id usb_pcwd_table [] = {
  97         { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
  98         { }                                     /* Terminating entry */
  99 };
 100 MODULE_DEVICE_TABLE (usb, usb_pcwd_table);
 101
 102 /* according to documentation max. time to process a command for the USB
 103  * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
 104 #define USB_COMMAND_TIMEOUT     250
 105
 106 /* Watchdog's internal commands */
 107 #define CMD_READ_TEMP                   0x02    /* Read Temperature; Re-trigger Watchdog */
 108 #define CMD_TRIGGER                     CMD_READ_TEMP
 109 #define CMD_GET_STATUS                  0x04    /* Get Status Information */
 110 #define CMD_GET_FIRMWARE_VERSION        0x08    /* Get Firmware Version */
 111 #define CMD_GET_DIP_SWITCH_SETTINGS     0x0c    /* Get Dip Switch Settings */
 112 #define CMD_READ_WATCHDOG_TIMEOUT       0x18    /* Read Current Watchdog Time */
 113 #define CMD_WRITE_WATCHDOG_TIMEOUT      0x19    /* Write Current Watchdog Time */
 114 #define CMD_ENABLE_WATCHDOG             0x30    /* Enable / Disable Watchdog */
 115 #define CMD_DISABLE_WATCHDOG            CMD_ENABLE_WATCHDOG
 116
 117 /* Some defines that I like to be somewhere else like include/linux/usb_hid.h */
 118 #define HID_REQ_SET_REPORT              0x09
 119 #define HID_DT_REPORT                   (USB_TYPE_CLASS | 0x02)
 120
 121 /* We can only use 1 card due to the /dev/watchdog restriction */
 122 static int cards_found;
 123
 124 /* some internal variables */
 125 static unsigned long is_active;
 126 static char expect_release;
 127
 128 /* Structure to hold all of our device specific stuff */
 129 struct usb_pcwd_private {
 130         struct usb_device *     udev;                   /* save off the usb device pointer */
 131         struct usb_interface *  interface;              /* the interface for this device */
 132
 133         unsigned int            interface_number;       /* the interface number used for cmd's */
 134
 135         unsigned char *         intr_buffer;            /* the buffer to intr data */
 136         dma_addr_t              intr_dma;               /* the dma address for the intr buffer */
 137         size_t                  intr_size;              /* the size of the intr buffer */
 138         struct urb *            intr_urb;               /* the urb used for the intr pipe */
 139
 140         unsigned char           cmd_command;            /* The command that is reported back */
 141         unsigned char           cmd_data_msb;           /* The data MSB that is reported back */
 142         unsigned char           cmd_data_lsb;           /* The data LSB that is reported back */
 143         atomic_t                cmd_received;           /* true if we received a report after a command */
 144
 145         int                     exists;                 /* Wether or not the device exists */
 146         struct semaphore        sem;                    /* locks this structure */
 147 };
 148 static struct usb_pcwd_private *usb_pcwd_device;
 149
 150 /* prevent races between open() and disconnect() */
 151 static DECLARE_MUTEX (disconnect_sem);
 152
 153 /* local function prototypes */
 154 static int usb_pcwd_probe       (struct usb_interface *interface, const struct usb_device_id *id);
 155 static void usb_pcwd_disconnect (struct usb_interface *interface);
 156
 157 /* usb specific object needed to register this driver with the usb subsystem */
 158 static struct usb_driver usb_pcwd_driver = {
 159         .owner =        THIS_MODULE,
 160         .name =         DRIVER_NAME,
 161         .probe =        usb_pcwd_probe,
 162         .disconnect =   usb_pcwd_disconnect,
 163         .id_table =     usb_pcwd_table,
 164 };
 165
 166
 167 static void usb_pcwd_intr_done(struct urb *urb, struct pt_regs *regs)
 168 {
 169         struct usb_pcwd_private *usb_pcwd = (struct usb_pcwd_private *)urb->context;
 170         unsigned char *data = usb_pcwd->intr_buffer;
 171         int retval;
 172
 173         switch (urb->status) {
 174         case 0:                 /* success */
 175                 break;
 176         case -ECONNRESET:       /* unlink */
 177         case -ENOENT:
 178         case -ESHUTDOWN:
 179                 /* this urb is terminated, clean up */
 180                 dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
 181                 return;
 182         /* -EPIPE:  should clear the halt */
 183         default:                /* error */
 184                 dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
 185                 goto resubmit;
 186         }
 187
 188         dbg("received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
 189                 data[0], data[1], data[2]);
 190
 191         usb_pcwd->cmd_command  = data[0];
 192         usb_pcwd->cmd_data_msb = data[1];
 193         usb_pcwd->cmd_data_lsb = data[2];
 194
 195         /* notify anyone waiting that the cmd has finished */
 196         atomic_set (&usb_pcwd->cmd_received, 1);
 197
 198 resubmit:
 199         retval = usb_submit_urb (urb, GFP_ATOMIC);
 200         if (retval)
 201                 printk(KERN_ERR PFX "can't resubmit intr, usb_submit_urb failed with result %d\n",
 202                         retval);
 203 }
 204
 205 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd, unsigned char cmd,
 206         unsigned char *msb, unsigned char *lsb)
 207 {
 208         int got_response, count;
 209         unsigned char buf[6];
 210
 211         /* We will not send any commands if the USB PCWD device does not exist */
 212         if ((!usb_pcwd) || (!usb_pcwd->exists))
 213                 return -1;
 214
 215         /* The USB PC Watchdog uses a 6 byte report format. The board currently uses
 216          * only 3 of the six bytes of the report. */
 217         buf[0] = cmd;                   /* Byte 0 = CMD */
 218         buf[1] = *msb;                  /* Byte 1 = Data MSB */
 219         buf[2] = *lsb;                  /* Byte 2 = Data LSB */
 220         buf[3] = buf[4] = buf[5] = 0;   /* All other bytes not used */
 221
 222         dbg("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
 223                 buf[0], buf[1], buf[2]);
 224
 225         atomic_set (&usb_pcwd->cmd_received, 0);
 226
 227         if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
 228                         HID_REQ_SET_REPORT, HID_DT_REPORT,
 229                         0x0200, usb_pcwd->interface_number, buf, sizeof(buf),
 230                         HZ) != sizeof(buf)) {
 231                 dbg("usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n", cmd, *msb, *lsb);
 232         }
 233         /* wait till the usb card processed the command,
 234          * with a max. timeout of USB_COMMAND_TIMEOUT */
 235         got_response = 0;
 236         for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response); count++) {
 237                 mdelay(1);
 238                 if (atomic_read (&usb_pcwd->cmd_received))
 239                         got_response = 1;
 240         }
 241
 242         if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
 243                 /* read back response */
 244                 *msb = usb_pcwd->cmd_data_msb;
 245                 *lsb = usb_pcwd->cmd_data_lsb;
 246         }
 247
 248         return got_response;
 249 }
 250
 251 static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
 252 {
 253         unsigned char msb = 0x00;
 254         unsigned char lsb = 0x00;
 255         int retval;
 256
 257         /* Enable Watchdog */
 258         retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG, &msb, &lsb);
 259
 260         if ((retval == 0) || (lsb == 0)) {
 261                 printk(KERN_ERR PFX "Card did not acknowledge enable attempt\n");
 262                 return -1;
 263         }
 264
 265         return 0;
 266 }
 267
 268 static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
 269 {
 270         unsigned char msb = 0xA5;
 271         unsigned char lsb = 0xC3;
 272         int retval;
 273
 274         /* Disable Watchdog */
 275         retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG, &msb, &lsb);
 276
 277         if ((retval == 0) || (lsb != 0)) {
 278                 printk(KERN_ERR PFX "Card did not acknowledge disable attempt\n");
 279                 return -1;
 280         }
 281
 282         return 0;
 283 }
 284
 285 static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
 286 {
 287         unsigned char dummy;
 288
 289         /* Re-trigger Watchdog */
 290         usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
 291
 292         return 0;
 293 }
 294
 295 static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
 296 {
 297         unsigned char msb = t / 256;
 298         unsigned char lsb = t % 256;
 299
 300         if ((t < 0x0001) || (t > 0xFFFF))
 301                 return -EINVAL;
 302
 303         /* Write new heartbeat to watchdog */
 304         usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
 305
 306         heartbeat = t;
 307         return 0;
 308 }
 309
 310 static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, int *temperature)
 311 {
 312         unsigned char msb, lsb;
 313
 314         usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
 315
 316         /*
 317          * Convert celsius to fahrenheit, since this was
 318          * the decided 'standard' for this return value.
 319          */
 320         *temperature = (lsb * 9 / 5) + 32;
 321
 322         return 0;
 323 }
 324
 325 /*
 326  *      /dev/watchdog handling
 327  */
 328
 329 static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
 330                               size_t len, loff_t *ppos)
 331 {
 332         /* Can't seek (pwrite) on this device  */
 333         if (ppos != &file->f_pos)
 334                 return -ESPIPE;
 335
 336         /* See if we got the magic character 'V' and reload the timer */
 337         if (len) {
 338                 if (!nowayout) {
 339                         size_t i;
 340
 341                         /* note: just in case someone wrote the magic character
 342                          * five months ago... */
 343                         expect_release = 0;
 344
 345                         /* scan to see whether or not we got the magic character */
 346                         for (i = 0; i != len; i++) {
 347                                 char c;
 348                                 if(get_user(c, data+i))
 349                                         return -EFAULT;
 350                                 if (c == 'V')
 351                                         expect_release = 42;
 352                         }
 353                 }
 354
 355                 /* someone wrote to us, we should reload the timer */
 356                 usb_pcwd_keepalive(usb_pcwd_device);
 357         }
 358         return len;
 359 }
 360
 361 static int usb_pcwd_ioctl(struct inode *inode, struct file *file,
 362                           unsigned int cmd, unsigned long arg)
 363 {
 364         void __user *argp = (void __user *)arg;
 365         int __user *p = argp;
 366         static struct watchdog_info ident = {
 367                 .options =              WDIOF_KEEPALIVEPING |
 368                                         WDIOF_SETTIMEOUT |
 369                                         WDIOF_MAGICCLOSE,
 370                 .firmware_version =     1,
 371                 .identity =             DRIVER_NAME,
 372         };
 373
 374         switch (cmd) {
 375                 case WDIOC_GETSUPPORT:
 376                         return copy_to_user(argp, &ident,
 377                                 sizeof (ident)) ? -EFAULT : 0;
 378
 379                 case WDIOC_GETSTATUS:
 380                 case WDIOC_GETBOOTSTATUS:
 381                         return put_user(0, p);
 382
 383                 case WDIOC_GETTEMP:
 384                 {
 385                         int temperature;
 386
 387                         if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
 388                                 return -EFAULT;
 389
 390                         return put_user(temperature, p);
 391                 }
 392
 393                 case WDIOC_KEEPALIVE:
 394                         usb_pcwd_keepalive(usb_pcwd_device);
 395                         return 0;
 396
 397                 case WDIOC_SETOPTIONS:
 398                 {
 399                         int new_options, retval = -EINVAL;
 400
 401                         if (get_user (new_options, p))
 402                                 return -EFAULT;
 403
 404                         if (new_options & WDIOS_DISABLECARD) {
 405                                 usb_pcwd_stop(usb_pcwd_device);
 406                                 retval = 0;
 407                         }
 408
 409                         if (new_options & WDIOS_ENABLECARD) {
 410                                 usb_pcwd_start(usb_pcwd_device);
 411                                 retval = 0;
 412                         }
 413
 414                         return retval;
 415                 }
 416
 417                 case WDIOC_SETTIMEOUT:
 418                 {
 419                         int new_heartbeat;
 420
 421                         if (get_user(new_heartbeat, p))
 422                                 return -EFAULT;
 423
 424                         if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
 425                             return -EINVAL;
 426
 427                         usb_pcwd_keepalive(usb_pcwd_device);
 428                         /* Fall */
 429                 }
 430
 431                 case WDIOC_GETTIMEOUT:
 432                         return put_user(heartbeat, p);
 433
 434                 default:
 435                         return -ENOIOCTLCMD;
 436         }
 437 }
 438
 439 static int usb_pcwd_open(struct inode *inode, struct file *file)
 440 {
 441         /* /dev/watchdog can only be opened once */
 442         if (test_and_set_bit(0, &is_active))
 443                 return -EBUSY;
 444
 445         /* Activate */
 446         usb_pcwd_start(usb_pcwd_device);
 447         usb_pcwd_keepalive(usb_pcwd_device);
 448         return 0;
 449 }
 450
 451 static int usb_pcwd_release(struct inode *inode, struct file *file)
 452 {
 453         /*
 454          *      Shut off the timer.
 455          */
 456         if (expect_release == 42) {
 457                 usb_pcwd_stop(usb_pcwd_device);
 458         } else {
 459                 printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
 460                 usb_pcwd_keepalive(usb_pcwd_device);
 461         }
 462         expect_release = 0;
 463         clear_bit(0, &is_active);
 464         return 0;
 465 }
 466
 467 /*
 468  *      /dev/temperature handling
 469  */
 470
 471 static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
 472                                 size_t len, loff_t *ppos)
 473 {
 474         int temperature;
 475
 476         /* Can't seek (pwrite) on this device  */
 477         if (ppos != &file->f_pos)
 478                 return -ESPIPE;
 479
 480         if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
 481                 return -EFAULT;
 482
 483         if (copy_to_user(data, &temperature, 1))
 484                 return -EFAULT;
 485
 486         return 1;
 487 }
 488
 489 static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
 490 {
 491         return 0;
 492 }
 493
 494 static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
 495 {
 496         return 0;
 497 }
 498
 499 /*
 500  *      Notify system
 501  */
 502
 503 static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
 504 {
 505         if (code==SYS_DOWN || code==SYS_HALT) {
 506                 /* Turn the WDT off */
 507                 usb_pcwd_stop(usb_pcwd_device);
 508         }
 509
 510         return NOTIFY_DONE;
 511 }
 512
 513 /*
 514  *      Kernel Interfaces
 515  */
 516
 517 static struct file_operations usb_pcwd_fops = {
 518         .owner =        THIS_MODULE,
 519         .llseek =       no_llseek,
 520         .write =        usb_pcwd_write,
 521         .ioctl =        usb_pcwd_ioctl,
 522         .open =         usb_pcwd_open,
 523         .release =      usb_pcwd_release,
 524 };
 525
 526 static struct miscdevice usb_pcwd_miscdev = {
 527         .minor =        WATCHDOG_MINOR,
 528         .name =         "watchdog",
 529         .fops =         &usb_pcwd_fops,
 530 };
 531
 532 static struct file_operations usb_pcwd_temperature_fops = {
 533         .owner =        THIS_MODULE,
 534         .llseek =       no_llseek,
 535         .read =         usb_pcwd_temperature_read,
 536         .open =         usb_pcwd_temperature_open,
 537         .release =      usb_pcwd_temperature_release,
 538 };
 539
 540 static struct miscdevice usb_pcwd_temperature_miscdev = {
 541         .minor =        TEMP_MINOR,
 542         .name =         "temperature",
 543         .fops =         &usb_pcwd_temperature_fops,
 544 };
 545
 546 static struct notifier_block usb_pcwd_notifier = {
 547         .notifier_call =        usb_pcwd_notify_sys,
 548 };
 549
 550 /**
 551  *      usb_pcwd_delete
 552  */
 553 static inline void usb_pcwd_delete (struct usb_pcwd_private *usb_pcwd)
 554 {
 555         if (usb_pcwd->intr_urb != NULL)
 556                 usb_free_urb (usb_pcwd->intr_urb);
 557         if (usb_pcwd->intr_buffer != NULL)
 558                 usb_buffer_free(usb_pcwd->udev, usb_pcwd->intr_size,
 559                                 usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
 560         kfree (usb_pcwd);
 561 }
 562
 563 /**
 564  *      usb_pcwd_probe
 565  *
 566  *      Called by the usb core when a new device is connected that it thinks
 567  *      this driver might be interested in.
 568  */
 569 static int usb_pcwd_probe(struct usb_interface *interface, const struct usb_device_id *id)
 570 {
 571         struct usb_device *udev = interface_to_usbdev(interface);
 572         struct usb_host_interface *iface_desc;
 573         struct usb_endpoint_descriptor *endpoint;
 574         struct usb_pcwd_private *usb_pcwd = NULL;
 575         int pipe, maxp;
 576         int retval = -ENOMEM;
 577         int got_fw_rev;
 578         unsigned char fw_rev_major, fw_rev_minor;
 579         char fw_ver_str[20];
 580         unsigned char option_switches, dummy;
 581
 582         /* See if the device offered us matches what we can accept */
 583         if ((udev->descriptor.idVendor != USB_PCWD_VENDOR_ID) ||
 584             (udev->descriptor.idProduct != USB_PCWD_PRODUCT_ID)) {
 585                 return -ENODEV;
 586         }
 587
 588         cards_found++;
 589         if (cards_found > 1) {
 590                 printk(KERN_ERR PFX "This driver only supports 1 device\n");
 591                 return -ENODEV;
 592         }
 593
 594         /* get the active interface descriptor */
 595         iface_desc = interface->cur_altsetting;
 596
 597         /* check out that we have a HID device */
 598         if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
 599                 printk(KERN_ERR PFX "The device isn't a Human Interface Device\n");
 600                 return -ENODEV;
 601         }
 602
 603         /* check out the endpoint: it has to be Interrupt & IN */
 604         endpoint = &iface_desc->endpoint[0].desc;
 605
 606         if (!((endpoint->bEndpointAddress & USB_DIR_IN) &&
 607              ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 608                                 == USB_ENDPOINT_XFER_INT))) {
 609                 /* we didn't find a Interrupt endpoint with direction IN */
 610                 printk(KERN_ERR PFX "Couldn't find an INTR & IN endpoint\n");
 611                 return -ENODEV;
 612         }
 613
 614         /* get a handle to the interrupt data pipe */
 615         pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
 616         maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
 617
 618         /* allocate memory for our device and initialize it */
 619         usb_pcwd = kmalloc (sizeof(struct usb_pcwd_private), GFP_KERNEL);
 620         if (usb_pcwd == NULL) {
 621                 printk(KERN_ERR PFX "Out of memory\n");
 622                 goto error;
 623         }
 624         memset (usb_pcwd, 0x00, sizeof (*usb_pcwd));
 625
 626         usb_pcwd_device = usb_pcwd;
 627
 628         init_MUTEX (&usb_pcwd->sem);
 629         usb_pcwd->udev = udev;
 630         usb_pcwd->interface = interface;
 631         usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
 632         usb_pcwd->intr_size = (endpoint->wMaxPacketSize > 8 ? endpoint->wMaxPacketSize : 8);
 633
 634         /* set up the memory buffer's */
 635         if (!(usb_pcwd->intr_buffer = usb_buffer_alloc(udev, usb_pcwd->intr_size, SLAB_ATOMIC, &usb_pcwd->intr_dma))) {
 636                 printk(KERN_ERR PFX "Out of memory\n");
 637                 goto error;
 638         }
 639
 640         /* allocate the urb's */
 641         usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
 642         if (!usb_pcwd->intr_urb) {
 643                 printk(KERN_ERR PFX "Out of memory\n");
 644                 goto error;
 645         }
 646
 647         /* initialise the intr urb's */
 648         usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
 649                         usb_pcwd->intr_buffer, usb_pcwd->intr_size,
 650                         usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
 651         usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
 652         usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 653
 654         /* register our interrupt URB with the USB system */
 655         if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
 656                 printk(KERN_ERR PFX "Problem registering interrupt URB\n");
 657                 retval = -EIO; /* failure */
 658                 goto error;
 659         }
 660
 661         /* The device exists and can be communicated with */
 662         usb_pcwd->exists = 1;
 663
 664         /* disable card */
 665         usb_pcwd_stop(usb_pcwd);
 666
 667         /* Get the Firmware Version */
 668         got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION, &fw_rev_major, &fw_rev_minor);
 669         if (got_fw_rev) {
 670                 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
 671         } else {
 672                 sprintf(fw_ver_str, "<card no answer>");
 673         }
 674
 675         printk(KERN_INFO PFX "Found card (Firmware: %s) with temp option\n",
 676                 fw_ver_str);
 677
 678         /* Get switch settings */
 679         usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy, &option_switches);
 680
 681         printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
 682                 option_switches,
 683                 ((option_switches & 0x10) ? "ON" : "OFF"),
 684                 ((option_switches & 0x08) ? "ON" : "OFF"));
 685
 686         /* Check that the heartbeat value is within it's range ; if not reset to the default */
 687         if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
 688                 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
 689                 printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
 690                         WATCHDOG_HEARTBEAT);
 691         }
 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_temperature_miscdev);
 701         if (retval != 0) {
 702                 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
 703                         TEMP_MINOR, retval);
 704                 goto err_out_unregister_reboot;
 705         }
 706
 707         retval = misc_register(&usb_pcwd_miscdev);
 708         if (retval != 0) {
 709                 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
 710                         WATCHDOG_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_temperature_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_miscdev);
 762         misc_deregister(&usb_pcwd_temperature_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 " v" DRIVER_VERSION " (" DRIVER_DATE ")\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);