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         .llseek = no_llseek,
 283 };
 284
 285 static irqreturn_t phantom_isr(int irq, void *data)
 286 {
 287         struct phantom_device *dev = data;
 288         unsigned int i;
 289         u32 ctl;
 290
 291         spin_lock(&dev->regs_lock);
 292         ctl = ioread32(dev->iaddr + PHN_CONTROL);
 293         if (!(ctl & PHN_CTL_IRQ)) {
 294                 spin_unlock(&dev->regs_lock);
 295                 return IRQ_NONE;
 296         }
 297
 298         iowrite32(0, dev->iaddr);
 299         iowrite32(0xc0, dev->iaddr);
 300
 301         if (dev->status & PHB_NOT_OH) {
 302                 struct phm_regs *r = &dev->oregs;
 303                 u32 m = min(r->count, 8U);
 304
 305                 for (i = 0; i < m; i++)
 306                         if (r->mask & BIT(i))
 307                                 iowrite32(r->values[i], dev->oaddr + i);
 308
 309                 dev->ctl_reg ^= PHN_CTL_AMP;
 310                 iowrite32(dev->ctl_reg, dev->iaddr + PHN_CONTROL);
 311         }
 312         spin_unlock(&dev->regs_lock);
 313
 314         ioread32(dev->iaddr); /* PCI posting */
 315
 316         atomic_inc(&dev->counter);
 317         wake_up_interruptible(&dev->wait);
 318
 319         return IRQ_HANDLED;
 320 }
 321
 322 /*
 323  * Init and deinit driver
 324  */
 325
 326 static unsigned int phantom_get_free(void)
 327 {
 328         unsigned int i;
 329
 330         for (i = 0; i < PHANTOM_MAX_MINORS; i++)
 331                 if (phantom_devices[i] == 0)
 332                         break;
 333
 334         return i;
 335 }
 336
 337 static int phantom_probe(struct pci_dev *pdev,
 338         const struct pci_device_id *pci_id)
 339 {
 340         struct phantom_device *pht;
 341         unsigned int minor;
 342         int retval;
 343
 344         retval = pci_enable_device(pdev);
 345         if (retval) {
 346                 dev_err(&pdev->dev, "pci_enable_device failed!\n");
 347                 goto err;
 348         }
 349
 350         minor = phantom_get_free();
 351         if (minor == PHANTOM_MAX_MINORS) {
 352                 dev_err(&pdev->dev, "too many devices found!\n");
 353                 retval = -EIO;
 354                 goto err_dis;
 355         }
 356
 357         phantom_devices[minor] = 1;
 358
 359         retval = pci_request_regions(pdev, "phantom");
 360         if (retval) {
 361                 dev_err(&pdev->dev, "pci_request_regions failed!\n");
 362                 goto err_null;
 363         }
 364
 365         retval = -ENOMEM;
 366         pht = kzalloc(sizeof(*pht), GFP_KERNEL);
 367         if (pht == NULL) {
 368                 dev_err(&pdev->dev, "unable to allocate device\n");
 369                 goto err_reg;
 370         }
 371
 372         pht->caddr = pci_iomap(pdev, 0, 0);
 373         if (pht->caddr == NULL) {
 374                 dev_err(&pdev->dev, "can't remap conf space\n");
 375                 goto err_fr;
 376         }
 377         pht->iaddr = pci_iomap(pdev, 2, 0);
 378         if (pht->iaddr == NULL) {
 379                 dev_err(&pdev->dev, "can't remap input space\n");
 380                 goto err_unmc;
 381         }
 382         pht->oaddr = pci_iomap(pdev, 3, 0);
 383         if (pht->oaddr == NULL) {
 384                 dev_err(&pdev->dev, "can't remap output space\n");
 385                 goto err_unmi;
 386         }
 387
 388         mutex_init(&pht->open_lock);
 389         spin_lock_init(&pht->regs_lock);
 390         init_waitqueue_head(&pht->wait);
 391         cdev_init(&pht->cdev, &phantom_file_ops);
 392         pht->cdev.owner = THIS_MODULE;
 393
 394         iowrite32(0, pht->caddr + PHN_IRQCTL);
 395         ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
 396         retval = request_irq(pdev->irq, phantom_isr,
 397                         IRQF_SHARED, "phantom", pht);
 398         if (retval) {
 399                 dev_err(&pdev->dev, "can't establish ISR\n");
 400                 goto err_unmo;
 401         }
 402
 403         retval = cdev_add(&pht->cdev, MKDEV(phantom_major, minor), 1);
 404         if (retval) {
 405                 dev_err(&pdev->dev, "chardev registration failed\n");
 406                 goto err_irq;
 407         }
 408
 409         if (IS_ERR(device_create(&phantom_class, &pdev->dev,
 410                                  MKDEV(phantom_major, minor), NULL,
 411                                  "phantom%u", minor)))
 412                 dev_err(&pdev->dev, "can't create device\n");
 413
 414         pci_set_drvdata(pdev, pht);
 415
 416         return 0;
 417 err_irq:
 418         free_irq(pdev->irq, pht);
 419 err_unmo:
 420         pci_iounmap(pdev, pht->oaddr);
 421 err_unmi:
 422         pci_iounmap(pdev, pht->iaddr);
 423 err_unmc:
 424         pci_iounmap(pdev, pht->caddr);
 425 err_fr:
 426         kfree(pht);
 427 err_reg:
 428         pci_release_regions(pdev);
 429 err_null:
 430         phantom_devices[minor] = 0;
 431 err_dis:
 432         pci_disable_device(pdev);
 433 err:
 434         return retval;
 435 }
 436
 437 static void phantom_remove(struct pci_dev *pdev)
 438 {
 439         struct phantom_device *pht = pci_get_drvdata(pdev);
 440         unsigned int minor = MINOR(pht->cdev.dev);
 441
 442         device_destroy(&phantom_class, MKDEV(phantom_major, minor));
 443
 444         cdev_del(&pht->cdev);
 445
 446         iowrite32(0, pht->caddr + PHN_IRQCTL);
 447         ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
 448         free_irq(pdev->irq, pht);
 449
 450         pci_iounmap(pdev, pht->oaddr);
 451         pci_iounmap(pdev, pht->iaddr);
 452         pci_iounmap(pdev, pht->caddr);
 453
 454         kfree(pht);
 455
 456         pci_release_regions(pdev);
 457
 458         phantom_devices[minor] = 0;
 459
 460         pci_disable_device(pdev);
 461 }
 462
 463 static int __maybe_unused phantom_suspend(struct device *dev_d)
 464 {
 465         struct phantom_device *dev = dev_get_drvdata(dev_d);
 466
 467         iowrite32(0, dev->caddr + PHN_IRQCTL);
 468         ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
 469
 470         synchronize_irq(to_pci_dev(dev_d)->irq);
 471
 472         return 0;
 473 }
 474
 475 static int __maybe_unused phantom_resume(struct device *dev_d)
 476 {
 477         struct phantom_device *dev = dev_get_drvdata(dev_d);
 478
 479         iowrite32(0, dev->caddr + PHN_IRQCTL);
 480
 481         return 0;
 482 }
 483
 484 static struct pci_device_id phantom_pci_tbl[] = {
 485         { .vendor = PCI_VENDOR_ID_PLX, .device = PCI_DEVICE_ID_PLX_9050,
 486           .subvendor = PCI_VENDOR_ID_PLX, .subdevice = PCI_DEVICE_ID_PLX_9050,
 487           .class = PCI_CLASS_BRIDGE_OTHER << 8, .class_mask = 0xffff00 },
 488         { 0, }
 489 };
 490 MODULE_DEVICE_TABLE(pci, phantom_pci_tbl);
 491
 492 static SIMPLE_DEV_PM_OPS(phantom_pm_ops, phantom_suspend, phantom_resume);
 493
 494 static struct pci_driver phantom_pci_driver = {
 495         .name = "phantom",
 496         .id_table = phantom_pci_tbl,
 497         .probe = phantom_probe,
 498         .remove = phantom_remove,
 499         .driver.pm = &phantom_pm_ops,
 500 };
 501
 502 static CLASS_ATTR_STRING(version, 0444, PHANTOM_VERSION);
 503
 504 static int __init phantom_init(void)
 505 {
 506         int retval;
 507         dev_t dev;
 508
 509         retval = class_register(&phantom_class);
 510         if (retval) {
 511                 printk(KERN_ERR "phantom: can't register phantom class\n");
 512                 goto err;
 513         }
 514         retval = class_create_file(&phantom_class, &class_attr_version.attr);
 515         if (retval) {
 516                 printk(KERN_ERR "phantom: can't create sysfs version file\n");
 517                 goto err_class;
 518         }
 519
 520         retval = alloc_chrdev_region(&dev, 0, PHANTOM_MAX_MINORS, "phantom");
 521         if (retval) {
 522                 printk(KERN_ERR "phantom: can't register character device\n");
 523                 goto err_attr;
 524         }
 525         phantom_major = MAJOR(dev);
 526
 527         retval = pci_register_driver(&phantom_pci_driver);
 528         if (retval) {
 529                 printk(KERN_ERR "phantom: can't register pci driver\n");
 530                 goto err_unchr;
 531         }
 532
 533         printk(KERN_INFO "Phantom Linux Driver, version " PHANTOM_VERSION ", "
 534                         "init OK\n");
 535
 536         return 0;
 537 err_unchr:
 538         unregister_chrdev_region(dev, PHANTOM_MAX_MINORS);
 539 err_attr:
 540         class_remove_file(&phantom_class, &class_attr_version.attr);
 541 err_class:
 542         class_unregister(&phantom_class);
 543 err:
 544         return retval;
 545 }
 546
 547 static void __exit phantom_exit(void)
 548 {
 549         pci_unregister_driver(&phantom_pci_driver);
 550
 551         unregister_chrdev_region(MKDEV(phantom_major, 0), PHANTOM_MAX_MINORS);
 552
 553         class_remove_file(&phantom_class, &class_attr_version.attr);
 554         class_unregister(&phantom_class);
 555
 556         pr_debug("phantom: module successfully removed\n");
 557 }
 558
 559 module_init(phantom_init);
 560 module_exit(phantom_exit);
 561
 562 MODULE_AUTHOR("Jiri Slaby <jirislaby@gmail.com>");
 563 MODULE_DESCRIPTION("Sensable Phantom driver (PCI devices)");
 564 MODULE_LICENSE("GPL");
 565 MODULE_VERSION(PHANTOM_VERSION);