drivers/misc/phantom.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Copyright (C) 2005-2007 Jiri Slaby <jirislaby@gmail.com>
   4  *
   5  *  You need a userspace library to cooperate with this driver. It (and other
   6  *  info) may be obtained here:
   7  *  http://www.fi.muni.cz/~xslaby/phantom.html
   8  *  or alternatively, you might use OpenHaptics provided by Sensable.
   9  */
  10
  11 #include <linux/compat.h>
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include <linux/device.h>
  15 #include <linux/pci.h>
  16 #include <linux/fs.h>
  17 #include <linux/poll.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/cdev.h>
  20 #include <linux/slab.h>
  21 #include <linux/phantom.h>
  22 #include <linux/sched.h>
  23 #include <linux/mutex.h>
  24
  25 #include <linux/atomic.h>
  26 #include <asm/io.h>
  27
  28 #define PHANTOM_VERSION         "n0.9.8"
  29
  30 #define PHANTOM_MAX_MINORS      8
  31
  32 #define PHN_IRQCTL              0x4c    /* irq control in caddr space */
  33
  34 #define PHB_RUNNING             1
  35 #define PHB_NOT_OH              2
  36
  37 static DEFINE_MUTEX(phantom_mutex);
  38 static int phantom_major;
  39
  40 static const struct class phantom_class = {
  41         .name = "phantom",
  42 };
  43
  44 struct phantom_device {
  45         unsigned int opened;
  46         void __iomem *caddr;
  47         u32 __iomem *iaddr;
  48         u32 __iomem *oaddr;
  49         unsigned long status;
  50         atomic_t counter;
  51
  52         wait_queue_head_t wait;
  53         struct cdev cdev;
  54
  55         struct mutex open_lock;
  56         spinlock_t regs_lock;
  57
  58         /* used in NOT_OH mode */
  59         struct phm_regs oregs;
  60         u32 ctl_reg;
  61 };
  62
  63 static unsigned char phantom_devices[PHANTOM_MAX_MINORS];
  64
  65 static int phantom_status(struct phantom_device *dev, unsigned long newstat)
  66 {
  67         pr_debug("phantom_status %lx %lx\n", dev->status, newstat);
  68
  69         if (!(dev->status & PHB_RUNNING) && (newstat & PHB_RUNNING)) {
  70                 atomic_set(&dev->counter, 0);
  71                 iowrite32(PHN_CTL_IRQ, dev->iaddr + PHN_CONTROL);
  72                 iowrite32(0x43, dev->caddr + PHN_IRQCTL);
  73                 ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
  74         } else if ((dev->status & PHB_RUNNING) && !(newstat & PHB_RUNNING)) {
  75                 iowrite32(0, dev->caddr + PHN_IRQCTL);
  76                 ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
  77         }
  78
  79         dev->status = newstat;
  80
  81         return 0;
  82 }
  83
  84 /*
  85  * File ops
  86  */
  87
  88 static long phantom_ioctl(struct file *file, unsigned int cmd,
  89                 unsigned long arg)
  90 {
  91         struct phantom_device *dev = file->private_data;
  92         struct phm_regs rs;
  93         struct phm_reg r;
  94         void __user *argp = (void __user *)arg;
  95         unsigned long flags;
  96         unsigned int i;
  97
  98         switch (cmd) {
  99         case PHN_SETREG:
 100         case PHN_SET_REG:
 101                 if (copy_from_user(&r, argp, sizeof(r)))
 102                         return -EFAULT;
 103
 104                 if (r.reg > 7)
 105                         return -EINVAL;
 106
 107                 spin_lock_irqsave(&dev->regs_lock, flags);
 108                 if (r.reg == PHN_CONTROL && (r.value & PHN_CTL_IRQ) &&
 109                                 phantom_status(dev, dev->status | PHB_RUNNING)){
 110                         spin_unlock_irqrestore(&dev->regs_lock, flags);
 111                         return -ENODEV;
 112                 }
 113
 114                 pr_debug("phantom: writing %x to %u\n", r.value, r.reg);
 115
 116                 /* preserve amp bit (don't allow to change it when in NOT_OH) */
 117                 if (r.reg == PHN_CONTROL && (dev->status & PHB_NOT_OH)) {
 118                         r.value &= ~PHN_CTL_AMP;
 119                         r.value |= dev->ctl_reg & PHN_CTL_AMP;
 120                         dev->ctl_reg = r.value;
 121                 }
 122
 123                 iowrite32(r.value, dev->iaddr + r.reg);
 124                 ioread32(dev->iaddr); /* PCI posting */
 125
 126                 if (r.reg == PHN_CONTROL && !(r.value & PHN_CTL_IRQ))
 127                         phantom_status(dev, dev->status & ~PHB_RUNNING);
 128                 spin_unlock_irqrestore(&dev->regs_lock, flags);
 129                 break;
 130         case PHN_SETREGS:
 131         case PHN_SET_REGS:
 132                 if (copy_from_user(&rs, argp, sizeof(rs)))
 133                         return -EFAULT;
 134
 135                 pr_debug("phantom: SRS %u regs %x\n", rs.count, rs.mask);
 136                 spin_lock_irqsave(&dev->regs_lock, flags);
 137                 if (dev->status & PHB_NOT_OH)
 138                         memcpy(&dev->oregs, &rs, sizeof(rs));
 139                 else {
 140                         u32 m = min(rs.count, 8U);
 141                         for (i = 0; i < m; i++)
 142                                 if (rs.mask & BIT(i))
 143                                         iowrite32(rs.values[i], dev->oaddr + i);
 144                         ioread32(dev->iaddr); /* PCI posting */
 145                 }
 146                 spin_unlock_irqrestore(&dev->regs_lock, flags);
 147                 break;
 148         case PHN_GETREG:
 149         case PHN_GET_REG:
 150                 if (copy_from_user(&r, argp, sizeof(r)))
 151                         return -EFAULT;
 152
 153                 if (r.reg > 7)
 154                         return -EINVAL;
 155
 156                 r.value = ioread32(dev->iaddr + r.reg);
 157
 158                 if (copy_to_user(argp, &r, sizeof(r)))
 159                         return -EFAULT;
 160                 break;
 161         case PHN_GETREGS:
 162         case PHN_GET_REGS: {
 163                 u32 m;
 164
 165                 if (copy_from_user(&rs, argp, sizeof(rs)))
 166                         return -EFAULT;
 167
 168                 m = min(rs.count, 8U);
 169
 170                 pr_debug("phantom: GRS %u regs %x\n", rs.count, rs.mask);
 171                 spin_lock_irqsave(&dev->regs_lock, flags);
 172                 for (i = 0; i < m; i++)
 173                         if (rs.mask & BIT(i))
 174                                 rs.values[i] = ioread32(dev->iaddr + i);
 175                 atomic_set(&dev->counter, 0);
 176                 spin_unlock_irqrestore(&dev->regs_lock, flags);
 177
 178                 if (copy_to_user(argp, &rs, sizeof(rs)))
 179                         return -EFAULT;
 180                 break;
 181         } case PHN_NOT_OH:
 182                 spin_lock_irqsave(&dev->regs_lock, flags);
 183                 if (dev->status & PHB_RUNNING) {
 184                         printk(KERN_ERR "phantom: you need to set NOT_OH "
 185                                         "before you start the device!\n");
 186                         spin_unlock_irqrestore(&dev->regs_lock, flags);
 187                         return -EINVAL;
 188                 }
 189                 dev->status |= PHB_NOT_OH;
 190                 spin_unlock_irqrestore(&dev->regs_lock, flags);
 191                 break;
 192         default:
 193                 return -ENOTTY;
 194         }
 195
 196         return 0;
 197 }
 198
 199 #ifdef CONFIG_COMPAT
 200 static long phantom_compat_ioctl(struct file *filp, unsigned int cmd,
 201                 unsigned long arg)
 202 {
 203         if (_IOC_NR(cmd) <= 3 && _IOC_SIZE(cmd) == sizeof(compat_uptr_t)) {
 204                 cmd &= ~(_IOC_SIZEMASK << _IOC_SIZESHIFT);
 205                 cmd |= sizeof(void *) << _IOC_SIZESHIFT;
 206         }
 207         return phantom_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
 208 }
 209 #else
 210 #define phantom_compat_ioctl NULL
 211 #endif
 212
 213 static int phantom_open(struct inode *inode, struct file *file)
 214 {
 215         struct phantom_device *dev = container_of(inode->i_cdev,
 216                         struct phantom_device, cdev);
 217
 218         mutex_lock(&phantom_mutex);
 219         nonseekable_open(inode, file);
 220
 221         if (mutex_lock_interruptible(&dev->open_lock)) {
 222                 mutex_unlock(&phantom_mutex);
 223                 return -ERESTARTSYS;
 224         }
 225
 226         if (dev->opened) {
 227                 mutex_unlock(&dev->open_lock);
 228                 mutex_unlock(&phantom_mutex);
 229                 return -EINVAL;
 230         }
 231
 232         WARN_ON(dev->status & PHB_NOT_OH);
 233
 234         file->private_data = dev;
 235
 236         atomic_set(&dev->counter, 0);
 237         dev->opened++;
 238         mutex_unlock(&dev->open_lock);
 239         mutex_unlock(&phantom_mutex);
 240         return 0;
 241 }
 242
 243 static int phantom_release(struct inode *inode, struct file *file)
 244 {
 245         struct phantom_device *dev = file->private_data;
 246
 247         mutex_lock(&dev->open_lock);
 248
 249         dev->opened = 0;
 250         phantom_status(dev, dev->status & ~PHB_RUNNING);
 251         dev->status &= ~PHB_NOT_OH;
 252
 253         mutex_unlock(&dev->open_lock);
 254
 255         return 0;
 256 }
 257
 258 static __poll_t phantom_poll(struct file *file, poll_table *wait)
 259 {
 260         struct phantom_device *dev = file->private_data;
 261         __poll_t mask = 0;
 262
 263         pr_debug("phantom_poll: %d\n", atomic_read(&dev->counter));
 264         poll_wait(file, &dev->wait, wait);
 265
 266         if (!(dev->status & PHB_RUNNING))
 267                 mask = EPOLLERR;
 268         else if (atomic_read(&dev->counter))
 269                 mask = EPOLLIN | EPOLLRDNORM;
 270
 271         pr_debug("phantom_poll end: %x/%d\n", mask, atomic_read(&dev->counter));
 272
 273         return mask;
 274 }
 275
 276 static const struct file_operations phantom_file_ops = {
 277         .open = phantom_open,
 278         .release = phantom_release,
 279         .unlocked_ioctl = phantom_ioctl,
 280         .compat_ioctl = phantom_compat_ioctl,
 281         .poll = phantom_poll,
 282 };
 283
 284 static irqreturn_t phantom_isr(int irq, void *data)
 285 {
 286         struct phantom_device *dev = data;
 287         unsigned int i;
 288         u32 ctl;
 289
 290         spin_lock(&dev->regs_lock);
 291         ctl = ioread32(dev->iaddr + PHN_CONTROL);
 292         if (!(ctl & PHN_CTL_IRQ)) {
 293                 spin_unlock(&dev->regs_lock);
 294                 return IRQ_NONE;
 295         }
 296
 297         iowrite32(0, dev->iaddr);
 298         iowrite32(0xc0, dev->iaddr);
 299
 300         if (dev->status & PHB_NOT_OH) {
 301                 struct phm_regs *r = &dev->oregs;
 302                 u32 m = min(r->count, 8U);
 303
 304                 for (i = 0; i < m; i++)
 305                         if (r->mask & BIT(i))
 306                                 iowrite32(r->values[i], dev->oaddr + i);
 307
 308                 dev->ctl_reg ^= PHN_CTL_AMP;
 309                 iowrite32(dev->ctl_reg, dev->iaddr + PHN_CONTROL);
 310         }
 311         spin_unlock(&dev->regs_lock);
 312
 313         ioread32(dev->iaddr); /* PCI posting */
 314
 315         atomic_inc(&dev->counter);
 316         wake_up_interruptible(&dev->wait);
 317
 318         return IRQ_HANDLED;
 319 }
 320
 321 /*
 322  * Init and deinit driver
 323  */
 324
 325 static unsigned int phantom_get_free(void)
 326 {
 327         unsigned int i;
 328
 329         for (i = 0; i < PHANTOM_MAX_MINORS; i++)
 330                 if (phantom_devices[i] == 0)
 331                         break;
 332
 333         return i;
 334 }
 335
 336 static int phantom_probe(struct pci_dev *pdev,
 337         const struct pci_device_id *pci_id)
 338 {
 339         struct phantom_device *pht;
 340         unsigned int minor;
 341         int retval;
 342
 343         retval = pci_enable_device(pdev);
 344         if (retval) {
 345                 dev_err(&pdev->dev, "pci_enable_device failed!\n");
 346                 goto err;
 347         }
 348
 349         minor = phantom_get_free();
 350         if (minor == PHANTOM_MAX_MINORS) {
 351                 dev_err(&pdev->dev, "too many devices found!\n");
 352                 retval = -EIO;
 353                 goto err_dis;
 354         }
 355
 356         phantom_devices[minor] = 1;
 357
 358         retval = pci_request_regions(pdev, "phantom");
 359         if (retval) {
 360                 dev_err(&pdev->dev, "pci_request_regions failed!\n");
 361                 goto err_null;
 362         }
 363
 364         retval = -ENOMEM;
 365         pht = kzalloc(sizeof(*pht), GFP_KERNEL);
 366         if (pht == NULL) {
 367                 dev_err(&pdev->dev, "unable to allocate device\n");
 368                 goto err_reg;
 369         }
 370
 371         pht->caddr = pci_iomap(pdev, 0, 0);
 372         if (pht->caddr == NULL) {
 373                 dev_err(&pdev->dev, "can't remap conf space\n");
 374                 goto err_fr;
 375         }
 376         pht->iaddr = pci_iomap(pdev, 2, 0);
 377         if (pht->iaddr == NULL) {
 378                 dev_err(&pdev->dev, "can't remap input space\n");
 379                 goto err_unmc;
 380         }
 381         pht->oaddr = pci_iomap(pdev, 3, 0);
 382         if (pht->oaddr == NULL) {
 383                 dev_err(&pdev->dev, "can't remap output space\n");
 384                 goto err_unmi;
 385         }
 386
 387         mutex_init(&pht->open_lock);
 388         spin_lock_init(&pht->regs_lock);
 389         init_waitqueue_head(&pht->wait);
 390         cdev_init(&pht->cdev, &phantom_file_ops);
 391         pht->cdev.owner = THIS_MODULE;
 392
 393         iowrite32(0, pht->caddr + PHN_IRQCTL);
 394         ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
 395         retval = request_irq(pdev->irq, phantom_isr,
 396                         IRQF_SHARED, "phantom", pht);
 397         if (retval) {
 398                 dev_err(&pdev->dev, "can't establish ISR\n");
 399                 goto err_unmo;
 400         }
 401
 402         retval = cdev_add(&pht->cdev, MKDEV(phantom_major, minor), 1);
 403         if (retval) {
 404                 dev_err(&pdev->dev, "chardev registration failed\n");
 405                 goto err_irq;
 406         }
 407
 408         if (IS_ERR(device_create(&phantom_class, &pdev->dev,
 409                                  MKDEV(phantom_major, minor), NULL,
 410                                  "phantom%u", minor)))
 411                 dev_err(&pdev->dev, "can't create device\n");
 412
 413         pci_set_drvdata(pdev, pht);
 414
 415         return 0;
 416 err_irq:
 417         free_irq(pdev->irq, pht);
 418 err_unmo:
 419         pci_iounmap(pdev, pht->oaddr);
 420 err_unmi:
 421         pci_iounmap(pdev, pht->iaddr);
 422 err_unmc:
 423         pci_iounmap(pdev, pht->caddr);
 424 err_fr:
 425         kfree(pht);
 426 err_reg:
 427         pci_release_regions(pdev);
 428 err_null:
 429         phantom_devices[minor] = 0;
 430 err_dis:
 431         pci_disable_device(pdev);
 432 err:
 433         return retval;
 434 }
 435
 436 static void phantom_remove(struct pci_dev *pdev)
 437 {
 438         struct phantom_device *pht = pci_get_drvdata(pdev);
 439         unsigned int minor = MINOR(pht->cdev.dev);
 440
 441         device_destroy(&phantom_class, MKDEV(phantom_major, minor));
 442
 443         cdev_del(&pht->cdev);
 444
 445         iowrite32(0, pht->caddr + PHN_IRQCTL);
 446         ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
 447         free_irq(pdev->irq, pht);
 448
 449         pci_iounmap(pdev, pht->oaddr);
 450         pci_iounmap(pdev, pht->iaddr);
 451         pci_iounmap(pdev, pht->caddr);
 452
 453         kfree(pht);
 454
 455         pci_release_regions(pdev);
 456
 457         phantom_devices[minor] = 0;
 458
 459         pci_disable_device(pdev);
 460 }
 461
 462 static int __maybe_unused phantom_suspend(struct device *dev_d)
 463 {
 464         struct phantom_device *dev = dev_get_drvdata(dev_d);
 465
 466         iowrite32(0, dev->caddr + PHN_IRQCTL);
 467         ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
 468
 469         synchronize_irq(to_pci_dev(dev_d)->irq);
 470
 471         return 0;
 472 }
 473
 474 static int __maybe_unused phantom_resume(struct device *dev_d)
 475 {
 476         struct phantom_device *dev = dev_get_drvdata(dev_d);
 477
 478         iowrite32(0, dev->caddr + PHN_IRQCTL);
 479
 480         return 0;
 481 }
 482
 483 static struct pci_device_id phantom_pci_tbl[] = {
 484         { .vendor = PCI_VENDOR_ID_PLX, .device = PCI_DEVICE_ID_PLX_9050,
 485           .subvendor = PCI_VENDOR_ID_PLX, .subdevice = PCI_DEVICE_ID_PLX_9050,
 486           .class = PCI_CLASS_BRIDGE_OTHER << 8, .class_mask = 0xffff00 },
 487         { 0, }
 488 };
 489 MODULE_DEVICE_TABLE(pci, phantom_pci_tbl);
 490
 491 static SIMPLE_DEV_PM_OPS(phantom_pm_ops, phantom_suspend, phantom_resume);
 492
 493 static struct pci_driver phantom_pci_driver = {
 494         .name = "phantom",
 495         .id_table = phantom_pci_tbl,
 496         .probe = phantom_probe,
 497         .remove = phantom_remove,
 498         .driver.pm = &phantom_pm_ops,
 499 };
 500
 501 static CLASS_ATTR_STRING(version, 0444, PHANTOM_VERSION);
 502
 503 static int __init phantom_init(void)
 504 {
 505         int retval;
 506         dev_t dev;
 507
 508         retval = class_register(&phantom_class);
 509         if (retval) {
 510                 printk(KERN_ERR "phantom: can't register phantom class\n");
 511                 goto err;
 512         }
 513         retval = class_create_file(&phantom_class, &class_attr_version.attr);
 514         if (retval) {
 515                 printk(KERN_ERR "phantom: can't create sysfs version file\n");
 516                 goto err_class;
 517         }
 518
 519         retval = alloc_chrdev_region(&dev, 0, PHANTOM_MAX_MINORS, "phantom");
 520         if (retval) {
 521                 printk(KERN_ERR "phantom: can't register character device\n");
 522                 goto err_attr;
 523         }
 524         phantom_major = MAJOR(dev);
 525
 526         retval = pci_register_driver(&phantom_pci_driver);
 527         if (retval) {
 528                 printk(KERN_ERR "phantom: can't register pci driver\n");
 529                 goto err_unchr;
 530         }
 531
 532         printk(KERN_INFO "Phantom Linux Driver, version " PHANTOM_VERSION ", "
 533                         "init OK\n");
 534
 535         return 0;
 536 err_unchr:
 537         unregister_chrdev_region(dev, PHANTOM_MAX_MINORS);
 538 err_attr:
 539         class_remove_file(&phantom_class, &class_attr_version.attr);
 540 err_class:
 541         class_unregister(&phantom_class);
 542 err:
 543         return retval;
 544 }
 545
 546 static void __exit phantom_exit(void)
 547 {
 548         pci_unregister_driver(&phantom_pci_driver);
 549
 550         unregister_chrdev_region(MKDEV(phantom_major, 0), PHANTOM_MAX_MINORS);
 551
 552         class_remove_file(&phantom_class, &class_attr_version.attr);
 553         class_unregister(&phantom_class);
 554
 555         pr_debug("phantom: module successfully removed\n");
 556 }
 557
 558 module_init(phantom_init);
 559 module_exit(phantom_exit);
 560
 561 MODULE_AUTHOR("Jiri Slaby <jirislaby@gmail.com>");
 562 MODULE_DESCRIPTION("Sensable Phantom driver (PCI devices)");
 563 MODULE_LICENSE("GPL");
 564 MODULE_VERSION(PHANTOM_VERSION);