xref: /linux/drivers/misc/phantom.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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);
565