phantom: BKL pushdown
[linux-2.6.git] / drivers / misc / phantom.c
1 /*
2  *  Copyright (C) 2005-2007 Jiri Slaby <jirislaby@gmail.com>
3  *
4  *  This program is free software; you can redistribute it and/or modify
5  *  it under the terms of the GNU General Public License as published by
6  *  the Free Software Foundation; either version 2 of the License, or
7  *  (at your option) any later version.
8  *
9  *  You need an userspace library to cooperate with this driver. It (and other
10  *  info) may be obtained here:
11  *  http://www.fi.muni.cz/~xslaby/phantom.html
12  *  or alternatively, you might use OpenHaptics provided by Sensable.
13  */
14
15 #include <linux/compat.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/device.h>
19 #include <linux/pci.h>
20 #include <linux/fs.h>
21 #include <linux/poll.h>
22 #include <linux/interrupt.h>
23 #include <linux/cdev.h>
24 #include <linux/phantom.h>
25 #include <linux/smp_lock.h>
26
27 #include <asm/atomic.h>
28 #include <asm/io.h>
29
30 #define PHANTOM_VERSION         "n0.9.8"
31
32 #define PHANTOM_MAX_MINORS      8
33
34 #define PHN_IRQCTL              0x4c    /* irq control in caddr space */
35
36 #define PHB_RUNNING             1
37 #define PHB_NOT_OH              2
38
39 static struct class *phantom_class;
40 static int phantom_major;
41
42 struct phantom_device {
43         unsigned int opened;
44         void __iomem *caddr;
45         u32 __iomem *iaddr;
46         u32 __iomem *oaddr;
47         unsigned long status;
48         atomic_t counter;
49
50         wait_queue_head_t wait;
51         struct cdev cdev;
52
53         struct mutex open_lock;
54         spinlock_t regs_lock;
55
56         /* used in NOT_OH mode */
57         struct phm_regs oregs;
58         u32 ctl_reg;
59 };
60
61 static unsigned char phantom_devices[PHANTOM_MAX_MINORS];
62
63 static int phantom_status(struct phantom_device *dev, unsigned long newstat)
64 {
65         pr_debug("phantom_status %lx %lx\n", dev->status, newstat);
66
67         if (!(dev->status & PHB_RUNNING) && (newstat & PHB_RUNNING)) {
68                 atomic_set(&dev->counter, 0);
69                 iowrite32(PHN_CTL_IRQ, dev->iaddr + PHN_CONTROL);
70                 iowrite32(0x43, dev->caddr + PHN_IRQCTL);
71                 ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
72         } else if ((dev->status & PHB_RUNNING) && !(newstat & PHB_RUNNING)) {
73                 iowrite32(0, dev->caddr + PHN_IRQCTL);
74                 ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
75         }
76
77         dev->status = newstat;
78
79         return 0;
80 }
81
82 /*
83  * File ops
84  */
85
86 static long phantom_ioctl(struct file *file, unsigned int cmd,
87                 unsigned long arg)
88 {
89         struct phantom_device *dev = file->private_data;
90         struct phm_regs rs;
91         struct phm_reg r;
92         void __user *argp = (void __user *)arg;
93         unsigned long flags;
94         unsigned int i;
95
96         switch (cmd) {
97         case PHN_SETREG:
98         case PHN_SET_REG:
99                 if (copy_from_user(&r, argp, sizeof(r)))
100                         return -EFAULT;
101
102                 if (r.reg > 7)
103                         return -EINVAL;
104
105                 spin_lock_irqsave(&dev->regs_lock, flags);
106                 if (r.reg == PHN_CONTROL && (r.value & PHN_CTL_IRQ) &&
107                                 phantom_status(dev, dev->status | PHB_RUNNING)){
108                         spin_unlock_irqrestore(&dev->regs_lock, flags);
109                         return -ENODEV;
110                 }
111
112                 pr_debug("phantom: writing %x to %u\n", r.value, r.reg);
113
114                 /* preserve amp bit (don't allow to change it when in NOT_OH) */
115                 if (r.reg == PHN_CONTROL && (dev->status & PHB_NOT_OH)) {
116                         r.value &= ~PHN_CTL_AMP;
117                         r.value |= dev->ctl_reg & PHN_CTL_AMP;
118                         dev->ctl_reg = r.value;
119                 }
120
121                 iowrite32(r.value, dev->iaddr + r.reg);
122                 ioread32(dev->iaddr); /* PCI posting */
123
124                 if (r.reg == PHN_CONTROL && !(r.value & PHN_CTL_IRQ))
125                         phantom_status(dev, dev->status & ~PHB_RUNNING);
126                 spin_unlock_irqrestore(&dev->regs_lock, flags);
127                 break;
128         case PHN_SETREGS:
129         case PHN_SET_REGS:
130                 if (copy_from_user(&rs, argp, sizeof(rs)))
131                         return -EFAULT;
132
133                 pr_debug("phantom: SRS %u regs %x\n", rs.count, rs.mask);
134                 spin_lock_irqsave(&dev->regs_lock, flags);
135                 if (dev->status & PHB_NOT_OH)
136                         memcpy(&dev->oregs, &rs, sizeof(rs));
137                 else {
138                         u32 m = min(rs.count, 8U);
139                         for (i = 0; i < m; i++)
140                                 if (rs.mask & BIT(i))
141                                         iowrite32(rs.values[i], dev->oaddr + i);
142                         ioread32(dev->iaddr); /* PCI posting */
143                 }
144                 spin_unlock_irqrestore(&dev->regs_lock, flags);
145                 break;
146         case PHN_GETREG:
147         case PHN_GET_REG:
148                 if (copy_from_user(&r, argp, sizeof(r)))
149                         return -EFAULT;
150
151                 if (r.reg > 7)
152                         return -EINVAL;
153
154                 r.value = ioread32(dev->iaddr + r.reg);
155
156                 if (copy_to_user(argp, &r, sizeof(r)))
157                         return -EFAULT;
158                 break;
159         case PHN_GETREGS:
160         case PHN_GET_REGS: {
161                 u32 m;
162
163                 if (copy_from_user(&rs, argp, sizeof(rs)))
164                         return -EFAULT;
165
166                 m = min(rs.count, 8U);
167
168                 pr_debug("phantom: GRS %u regs %x\n", rs.count, rs.mask);
169                 spin_lock_irqsave(&dev->regs_lock, flags);
170                 for (i = 0; i < m; i++)
171                         if (rs.mask & BIT(i))
172                                 rs.values[i] = ioread32(dev->iaddr + i);
173                 atomic_set(&dev->counter, 0);
174                 spin_unlock_irqrestore(&dev->regs_lock, flags);
175
176                 if (copy_to_user(argp, &rs, sizeof(rs)))
177                         return -EFAULT;
178                 break;
179         } case PHN_NOT_OH:
180                 spin_lock_irqsave(&dev->regs_lock, flags);
181                 if (dev->status & PHB_RUNNING) {
182                         printk(KERN_ERR "phantom: you need to set NOT_OH "
183                                         "before you start the device!\n");
184                         spin_unlock_irqrestore(&dev->regs_lock, flags);
185                         return -EINVAL;
186                 }
187                 dev->status |= PHB_NOT_OH;
188                 spin_unlock_irqrestore(&dev->regs_lock, flags);
189                 break;
190         default:
191                 return -ENOTTY;
192         }
193
194         return 0;
195 }
196
197 #ifdef CONFIG_COMPAT
198 static long phantom_compat_ioctl(struct file *filp, unsigned int cmd,
199                 unsigned long arg)
200 {
201         if (_IOC_NR(cmd) <= 3 && _IOC_SIZE(cmd) == sizeof(compat_uptr_t)) {
202                 cmd &= ~(_IOC_SIZEMASK << _IOC_SIZESHIFT);
203                 cmd |= sizeof(void *) << _IOC_SIZESHIFT;
204         }
205         return phantom_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
206 }
207 #else
208 #define phantom_compat_ioctl NULL
209 #endif
210
211 static int phantom_open(struct inode *inode, struct file *file)
212 {
213         struct phantom_device *dev = container_of(inode->i_cdev,
214                         struct phantom_device, cdev);
215
216         lock_kernel();
217         nonseekable_open(inode, file);
218
219         if (mutex_lock_interruptible(&dev->open_lock)) {
220                 unlock_kernel();
221                 return -ERESTARTSYS;
222         }
223
224         if (dev->opened) {
225                 mutex_unlock(&dev->open_lock);
226                 unlock_kernel();
227                 return -EINVAL;
228         }
229
230         WARN_ON(dev->status & PHB_NOT_OH);
231
232         file->private_data = dev;
233
234         atomic_set(&dev->counter, 0);
235         dev->opened++;
236         mutex_unlock(&dev->open_lock);
237         unlock_kernel();
238         return 0;
239 }
240
241 static int phantom_release(struct inode *inode, struct file *file)
242 {
243         struct phantom_device *dev = file->private_data;
244
245         mutex_lock(&dev->open_lock);
246
247         dev->opened = 0;
248         phantom_status(dev, dev->status & ~PHB_RUNNING);
249         dev->status &= ~PHB_NOT_OH;
250
251         mutex_unlock(&dev->open_lock);
252
253         return 0;
254 }
255
256 static unsigned int phantom_poll(struct file *file, poll_table *wait)
257 {
258         struct phantom_device *dev = file->private_data;
259         unsigned int mask = 0;
260
261         pr_debug("phantom_poll: %d\n", atomic_read(&dev->counter));
262         poll_wait(file, &dev->wait, wait);
263
264         if (!(dev->status & PHB_RUNNING))
265                 mask = POLLERR;
266         else if (atomic_read(&dev->counter))
267                 mask = POLLIN | POLLRDNORM;
268
269         pr_debug("phantom_poll end: %x/%d\n", mask, atomic_read(&dev->counter));
270
271         return mask;
272 }
273
274 static struct file_operations phantom_file_ops = {
275         .open = phantom_open,
276         .release = phantom_release,
277         .unlocked_ioctl = phantom_ioctl,
278         .compat_ioctl = phantom_compat_ioctl,
279         .poll = phantom_poll,
280 };
281
282 static irqreturn_t phantom_isr(int irq, void *data)
283 {
284         struct phantom_device *dev = data;
285         unsigned int i;
286         u32 ctl;
287
288         spin_lock(&dev->regs_lock);
289         ctl = ioread32(dev->iaddr + PHN_CONTROL);
290         if (!(ctl & PHN_CTL_IRQ)) {
291                 spin_unlock(&dev->regs_lock);
292                 return IRQ_NONE;
293         }
294
295         iowrite32(0, dev->iaddr);
296         iowrite32(0xc0, dev->iaddr);
297
298         if (dev->status & PHB_NOT_OH) {
299                 struct phm_regs *r = &dev->oregs;
300                 u32 m = min(r->count, 8U);
301
302                 for (i = 0; i < m; i++)
303                         if (r->mask & BIT(i))
304                                 iowrite32(r->values[i], dev->oaddr + i);
305
306                 dev->ctl_reg ^= PHN_CTL_AMP;
307                 iowrite32(dev->ctl_reg, dev->iaddr + PHN_CONTROL);
308         }
309         spin_unlock(&dev->regs_lock);
310
311         ioread32(dev->iaddr); /* PCI posting */
312
313         atomic_inc(&dev->counter);
314         wake_up_interruptible(&dev->wait);
315
316         return IRQ_HANDLED;
317 }
318
319 /*
320  * Init and deinit driver
321  */
322
323 static unsigned int __devinit phantom_get_free(void)
324 {
325         unsigned int i;
326
327         for (i = 0; i < PHANTOM_MAX_MINORS; i++)
328                 if (phantom_devices[i] == 0)
329                         break;
330
331         return i;
332 }
333
334 static int __devinit phantom_probe(struct pci_dev *pdev,
335         const struct pci_device_id *pci_id)
336 {
337         struct phantom_device *pht;
338         unsigned int minor;
339         int retval;
340
341         retval = pci_enable_device(pdev);
342         if (retval)
343                 goto err;
344
345         minor = phantom_get_free();
346         if (minor == PHANTOM_MAX_MINORS) {
347                 dev_err(&pdev->dev, "too many devices found!\n");
348                 retval = -EIO;
349                 goto err_dis;
350         }
351
352         phantom_devices[minor] = 1;
353
354         retval = pci_request_regions(pdev, "phantom");
355         if (retval)
356                 goto err_null;
357
358         retval = -ENOMEM;
359         pht = kzalloc(sizeof(*pht), GFP_KERNEL);
360         if (pht == NULL) {
361                 dev_err(&pdev->dev, "unable to allocate device\n");
362                 goto err_reg;
363         }
364
365         pht->caddr = pci_iomap(pdev, 0, 0);
366         if (pht->caddr == NULL) {
367                 dev_err(&pdev->dev, "can't remap conf space\n");
368                 goto err_fr;
369         }
370         pht->iaddr = pci_iomap(pdev, 2, 0);
371         if (pht->iaddr == NULL) {
372                 dev_err(&pdev->dev, "can't remap input space\n");
373                 goto err_unmc;
374         }
375         pht->oaddr = pci_iomap(pdev, 3, 0);
376         if (pht->oaddr == NULL) {
377                 dev_err(&pdev->dev, "can't remap output space\n");
378                 goto err_unmi;
379         }
380
381         mutex_init(&pht->open_lock);
382         spin_lock_init(&pht->regs_lock);
383         init_waitqueue_head(&pht->wait);
384         cdev_init(&pht->cdev, &phantom_file_ops);
385         pht->cdev.owner = THIS_MODULE;
386
387         iowrite32(0, pht->caddr + PHN_IRQCTL);
388         ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
389         retval = request_irq(pdev->irq, phantom_isr,
390                         IRQF_SHARED | IRQF_DISABLED, "phantom", pht);
391         if (retval) {
392                 dev_err(&pdev->dev, "can't establish ISR\n");
393                 goto err_unmo;
394         }
395
396         retval = cdev_add(&pht->cdev, MKDEV(phantom_major, minor), 1);
397         if (retval) {
398                 dev_err(&pdev->dev, "chardev registration failed\n");
399                 goto err_irq;
400         }
401
402         if (IS_ERR(device_create(phantom_class, &pdev->dev, MKDEV(phantom_major,
403                         minor), "phantom%u", minor)))
404                 dev_err(&pdev->dev, "can't create device\n");
405
406         pci_set_drvdata(pdev, pht);
407
408         return 0;
409 err_irq:
410         free_irq(pdev->irq, pht);
411 err_unmo:
412         pci_iounmap(pdev, pht->oaddr);
413 err_unmi:
414         pci_iounmap(pdev, pht->iaddr);
415 err_unmc:
416         pci_iounmap(pdev, pht->caddr);
417 err_fr:
418         kfree(pht);
419 err_reg:
420         pci_release_regions(pdev);
421 err_null:
422         phantom_devices[minor] = 0;
423 err_dis:
424         pci_disable_device(pdev);
425 err:
426         return retval;
427 }
428
429 static void __devexit phantom_remove(struct pci_dev *pdev)
430 {
431         struct phantom_device *pht = pci_get_drvdata(pdev);
432         unsigned int minor = MINOR(pht->cdev.dev);
433
434         device_destroy(phantom_class, MKDEV(phantom_major, minor));
435
436         cdev_del(&pht->cdev);
437
438         iowrite32(0, pht->caddr + PHN_IRQCTL);
439         ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
440         free_irq(pdev->irq, pht);
441
442         pci_iounmap(pdev, pht->oaddr);
443         pci_iounmap(pdev, pht->iaddr);
444         pci_iounmap(pdev, pht->caddr);
445
446         kfree(pht);
447
448         pci_release_regions(pdev);
449
450         phantom_devices[minor] = 0;
451
452         pci_disable_device(pdev);
453 }
454
455 #ifdef CONFIG_PM
456 static int phantom_suspend(struct pci_dev *pdev, pm_message_t state)
457 {
458         struct phantom_device *dev = pci_get_drvdata(pdev);
459
460         iowrite32(0, dev->caddr + PHN_IRQCTL);
461         ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
462
463         synchronize_irq(pdev->irq);
464
465         return 0;
466 }
467
468 static int phantom_resume(struct pci_dev *pdev)
469 {
470         struct phantom_device *dev = pci_get_drvdata(pdev);
471
472         iowrite32(0, dev->caddr + PHN_IRQCTL);
473
474         return 0;
475 }
476 #else
477 #define phantom_suspend NULL
478 #define phantom_resume  NULL
479 #endif
480
481 static struct pci_device_id phantom_pci_tbl[] __devinitdata = {
482         { .vendor = PCI_VENDOR_ID_PLX, .device = PCI_DEVICE_ID_PLX_9050,
483           .subvendor = PCI_VENDOR_ID_PLX, .subdevice = PCI_DEVICE_ID_PLX_9050,
484           .class = PCI_CLASS_BRIDGE_OTHER << 8, .class_mask = 0xffff00 },
485         { 0, }
486 };
487 MODULE_DEVICE_TABLE(pci, phantom_pci_tbl);
488
489 static struct pci_driver phantom_pci_driver = {
490         .name = "phantom",
491         .id_table = phantom_pci_tbl,
492         .probe = phantom_probe,
493         .remove = __devexit_p(phantom_remove),
494         .suspend = phantom_suspend,
495         .resume = phantom_resume
496 };
497
498 static ssize_t phantom_show_version(struct class *cls, char *buf)
499 {
500         return sprintf(buf, PHANTOM_VERSION "\n");
501 }
502
503 static CLASS_ATTR(version, 0444, phantom_show_version, NULL);
504
505 static int __init phantom_init(void)
506 {
507         int retval;
508         dev_t dev;
509
510         phantom_class = class_create(THIS_MODULE, "phantom");
511         if (IS_ERR(phantom_class)) {
512                 retval = PTR_ERR(phantom_class);
513                 printk(KERN_ERR "phantom: can't register phantom class\n");
514                 goto err;
515         }
516         retval = class_create_file(phantom_class, &class_attr_version);
517         if (retval) {
518                 printk(KERN_ERR "phantom: can't create sysfs version file\n");
519                 goto err_class;
520         }
521
522         retval = alloc_chrdev_region(&dev, 0, PHANTOM_MAX_MINORS, "phantom");
523         if (retval) {
524                 printk(KERN_ERR "phantom: can't register character device\n");
525                 goto err_attr;
526         }
527         phantom_major = MAJOR(dev);
528
529         retval = pci_register_driver(&phantom_pci_driver);
530         if (retval) {
531                 printk(KERN_ERR "phantom: can't register pci driver\n");
532                 goto err_unchr;
533         }
534
535         printk(KERN_INFO "Phantom Linux Driver, version " PHANTOM_VERSION ", "
536                         "init OK\n");
537
538         return 0;
539 err_unchr:
540         unregister_chrdev_region(dev, PHANTOM_MAX_MINORS);
541 err_attr:
542         class_remove_file(phantom_class, &class_attr_version);
543 err_class:
544         class_destroy(phantom_class);
545 err:
546         return retval;
547 }
548
549 static void __exit phantom_exit(void)
550 {
551         pci_unregister_driver(&phantom_pci_driver);
552
553         unregister_chrdev_region(MKDEV(phantom_major, 0), PHANTOM_MAX_MINORS);
554
555         class_remove_file(phantom_class, &class_attr_version);
556         class_destroy(phantom_class);
557
558         pr_debug("phantom: module successfully removed\n");
559 }
560
561 module_init(phantom_init);
562 module_exit(phantom_exit);
563
564 MODULE_AUTHOR("Jiri Slaby <jirislaby@gmail.com>");
565 MODULE_DESCRIPTION("Sensable Phantom driver");
566 MODULE_LICENSE("GPL");
567 MODULE_VERSION(PHANTOM_VERSION);