xref: /linux/drivers/misc/phantom.c (revision 2363088eba2ecccfb643725e4864af73c4226a04)
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 struct class *phantom_class;
39 static int phantom_major;
40 
41 struct phantom_device {
42 	unsigned int opened;
43 	void __iomem *caddr;
44 	u32 __iomem *iaddr;
45 	u32 __iomem *oaddr;
46 	unsigned long status;
47 	atomic_t counter;
48 
49 	wait_queue_head_t wait;
50 	struct cdev cdev;
51 
52 	struct mutex open_lock;
53 	spinlock_t regs_lock;
54 
55 	/* used in NOT_OH mode */
56 	struct phm_regs oregs;
57 	u32 ctl_reg;
58 };
59 
60 static unsigned char phantom_devices[PHANTOM_MAX_MINORS];
61 
62 static int phantom_status(struct phantom_device *dev, unsigned long newstat)
63 {
64 	pr_debug("phantom_status %lx %lx\n", dev->status, newstat);
65 
66 	if (!(dev->status & PHB_RUNNING) && (newstat & PHB_RUNNING)) {
67 		atomic_set(&dev->counter, 0);
68 		iowrite32(PHN_CTL_IRQ, dev->iaddr + PHN_CONTROL);
69 		iowrite32(0x43, dev->caddr + PHN_IRQCTL);
70 		ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
71 	} else if ((dev->status & PHB_RUNNING) && !(newstat & PHB_RUNNING)) {
72 		iowrite32(0, dev->caddr + PHN_IRQCTL);
73 		ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
74 	}
75 
76 	dev->status = newstat;
77 
78 	return 0;
79 }
80 
81 /*
82  * File ops
83  */
84 
85 static long phantom_ioctl(struct file *file, unsigned int cmd,
86 		unsigned long arg)
87 {
88 	struct phantom_device *dev = file->private_data;
89 	struct phm_regs rs;
90 	struct phm_reg r;
91 	void __user *argp = (void __user *)arg;
92 	unsigned long flags;
93 	unsigned int i;
94 
95 	switch (cmd) {
96 	case PHN_SETREG:
97 	case PHN_SET_REG:
98 		if (copy_from_user(&r, argp, sizeof(r)))
99 			return -EFAULT;
100 
101 		if (r.reg > 7)
102 			return -EINVAL;
103 
104 		spin_lock_irqsave(&dev->regs_lock, flags);
105 		if (r.reg == PHN_CONTROL && (r.value & PHN_CTL_IRQ) &&
106 				phantom_status(dev, dev->status | PHB_RUNNING)){
107 			spin_unlock_irqrestore(&dev->regs_lock, flags);
108 			return -ENODEV;
109 		}
110 
111 		pr_debug("phantom: writing %x to %u\n", r.value, r.reg);
112 
113 		/* preserve amp bit (don't allow to change it when in NOT_OH) */
114 		if (r.reg == PHN_CONTROL && (dev->status & PHB_NOT_OH)) {
115 			r.value &= ~PHN_CTL_AMP;
116 			r.value |= dev->ctl_reg & PHN_CTL_AMP;
117 			dev->ctl_reg = r.value;
118 		}
119 
120 		iowrite32(r.value, dev->iaddr + r.reg);
121 		ioread32(dev->iaddr); /* PCI posting */
122 
123 		if (r.reg == PHN_CONTROL && !(r.value & PHN_CTL_IRQ))
124 			phantom_status(dev, dev->status & ~PHB_RUNNING);
125 		spin_unlock_irqrestore(&dev->regs_lock, flags);
126 		break;
127 	case PHN_SETREGS:
128 	case PHN_SET_REGS:
129 		if (copy_from_user(&rs, argp, sizeof(rs)))
130 			return -EFAULT;
131 
132 		pr_debug("phantom: SRS %u regs %x\n", rs.count, rs.mask);
133 		spin_lock_irqsave(&dev->regs_lock, flags);
134 		if (dev->status & PHB_NOT_OH)
135 			memcpy(&dev->oregs, &rs, sizeof(rs));
136 		else {
137 			u32 m = min(rs.count, 8U);
138 			for (i = 0; i < m; i++)
139 				if (rs.mask & BIT(i))
140 					iowrite32(rs.values[i], dev->oaddr + i);
141 			ioread32(dev->iaddr); /* PCI posting */
142 		}
143 		spin_unlock_irqrestore(&dev->regs_lock, flags);
144 		break;
145 	case PHN_GETREG:
146 	case PHN_GET_REG:
147 		if (copy_from_user(&r, argp, sizeof(r)))
148 			return -EFAULT;
149 
150 		if (r.reg > 7)
151 			return -EINVAL;
152 
153 		r.value = ioread32(dev->iaddr + r.reg);
154 
155 		if (copy_to_user(argp, &r, sizeof(r)))
156 			return -EFAULT;
157 		break;
158 	case PHN_GETREGS:
159 	case PHN_GET_REGS: {
160 		u32 m;
161 
162 		if (copy_from_user(&rs, argp, sizeof(rs)))
163 			return -EFAULT;
164 
165 		m = min(rs.count, 8U);
166 
167 		pr_debug("phantom: GRS %u regs %x\n", rs.count, rs.mask);
168 		spin_lock_irqsave(&dev->regs_lock, flags);
169 		for (i = 0; i < m; i++)
170 			if (rs.mask & BIT(i))
171 				rs.values[i] = ioread32(dev->iaddr + i);
172 		atomic_set(&dev->counter, 0);
173 		spin_unlock_irqrestore(&dev->regs_lock, flags);
174 
175 		if (copy_to_user(argp, &rs, sizeof(rs)))
176 			return -EFAULT;
177 		break;
178 	} case PHN_NOT_OH:
179 		spin_lock_irqsave(&dev->regs_lock, flags);
180 		if (dev->status & PHB_RUNNING) {
181 			printk(KERN_ERR "phantom: you need to set NOT_OH "
182 					"before you start the device!\n");
183 			spin_unlock_irqrestore(&dev->regs_lock, flags);
184 			return -EINVAL;
185 		}
186 		dev->status |= PHB_NOT_OH;
187 		spin_unlock_irqrestore(&dev->regs_lock, flags);
188 		break;
189 	default:
190 		return -ENOTTY;
191 	}
192 
193 	return 0;
194 }
195 
196 #ifdef CONFIG_COMPAT
197 static long phantom_compat_ioctl(struct file *filp, unsigned int cmd,
198 		unsigned long arg)
199 {
200 	if (_IOC_NR(cmd) <= 3 && _IOC_SIZE(cmd) == sizeof(compat_uptr_t)) {
201 		cmd &= ~(_IOC_SIZEMASK << _IOC_SIZESHIFT);
202 		cmd |= sizeof(void *) << _IOC_SIZESHIFT;
203 	}
204 	return phantom_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
205 }
206 #else
207 #define phantom_compat_ioctl NULL
208 #endif
209 
210 static int phantom_open(struct inode *inode, struct file *file)
211 {
212 	struct phantom_device *dev = container_of(inode->i_cdev,
213 			struct phantom_device, cdev);
214 
215 	mutex_lock(&phantom_mutex);
216 	nonseekable_open(inode, file);
217 
218 	if (mutex_lock_interruptible(&dev->open_lock)) {
219 		mutex_unlock(&phantom_mutex);
220 		return -ERESTARTSYS;
221 	}
222 
223 	if (dev->opened) {
224 		mutex_unlock(&dev->open_lock);
225 		mutex_unlock(&phantom_mutex);
226 		return -EINVAL;
227 	}
228 
229 	WARN_ON(dev->status & PHB_NOT_OH);
230 
231 	file->private_data = dev;
232 
233 	atomic_set(&dev->counter, 0);
234 	dev->opened++;
235 	mutex_unlock(&dev->open_lock);
236 	mutex_unlock(&phantom_mutex);
237 	return 0;
238 }
239 
240 static int phantom_release(struct inode *inode, struct file *file)
241 {
242 	struct phantom_device *dev = file->private_data;
243 
244 	mutex_lock(&dev->open_lock);
245 
246 	dev->opened = 0;
247 	phantom_status(dev, dev->status & ~PHB_RUNNING);
248 	dev->status &= ~PHB_NOT_OH;
249 
250 	mutex_unlock(&dev->open_lock);
251 
252 	return 0;
253 }
254 
255 static __poll_t phantom_poll(struct file *file, poll_table *wait)
256 {
257 	struct phantom_device *dev = file->private_data;
258 	__poll_t mask = 0;
259 
260 	pr_debug("phantom_poll: %d\n", atomic_read(&dev->counter));
261 	poll_wait(file, &dev->wait, wait);
262 
263 	if (!(dev->status & PHB_RUNNING))
264 		mask = EPOLLERR;
265 	else if (atomic_read(&dev->counter))
266 		mask = EPOLLIN | EPOLLRDNORM;
267 
268 	pr_debug("phantom_poll end: %x/%d\n", mask, atomic_read(&dev->counter));
269 
270 	return mask;
271 }
272 
273 static const struct file_operations phantom_file_ops = {
274 	.open = phantom_open,
275 	.release = phantom_release,
276 	.unlocked_ioctl = phantom_ioctl,
277 	.compat_ioctl = phantom_compat_ioctl,
278 	.poll = phantom_poll,
279 	.llseek = no_llseek,
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 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 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 		dev_err(&pdev->dev, "pci_enable_device failed!\n");
344 		goto err;
345 	}
346 
347 	minor = phantom_get_free();
348 	if (minor == PHANTOM_MAX_MINORS) {
349 		dev_err(&pdev->dev, "too many devices found!\n");
350 		retval = -EIO;
351 		goto err_dis;
352 	}
353 
354 	phantom_devices[minor] = 1;
355 
356 	retval = pci_request_regions(pdev, "phantom");
357 	if (retval) {
358 		dev_err(&pdev->dev, "pci_request_regions failed!\n");
359 		goto err_null;
360 	}
361 
362 	retval = -ENOMEM;
363 	pht = kzalloc(sizeof(*pht), GFP_KERNEL);
364 	if (pht == NULL) {
365 		dev_err(&pdev->dev, "unable to allocate device\n");
366 		goto err_reg;
367 	}
368 
369 	pht->caddr = pci_iomap(pdev, 0, 0);
370 	if (pht->caddr == NULL) {
371 		dev_err(&pdev->dev, "can't remap conf space\n");
372 		goto err_fr;
373 	}
374 	pht->iaddr = pci_iomap(pdev, 2, 0);
375 	if (pht->iaddr == NULL) {
376 		dev_err(&pdev->dev, "can't remap input space\n");
377 		goto err_unmc;
378 	}
379 	pht->oaddr = pci_iomap(pdev, 3, 0);
380 	if (pht->oaddr == NULL) {
381 		dev_err(&pdev->dev, "can't remap output space\n");
382 		goto err_unmi;
383 	}
384 
385 	mutex_init(&pht->open_lock);
386 	spin_lock_init(&pht->regs_lock);
387 	init_waitqueue_head(&pht->wait);
388 	cdev_init(&pht->cdev, &phantom_file_ops);
389 	pht->cdev.owner = THIS_MODULE;
390 
391 	iowrite32(0, pht->caddr + PHN_IRQCTL);
392 	ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
393 	retval = request_irq(pdev->irq, phantom_isr,
394 			IRQF_SHARED, "phantom", pht);
395 	if (retval) {
396 		dev_err(&pdev->dev, "can't establish ISR\n");
397 		goto err_unmo;
398 	}
399 
400 	retval = cdev_add(&pht->cdev, MKDEV(phantom_major, minor), 1);
401 	if (retval) {
402 		dev_err(&pdev->dev, "chardev registration failed\n");
403 		goto err_irq;
404 	}
405 
406 	if (IS_ERR(device_create(phantom_class, &pdev->dev,
407 				 MKDEV(phantom_major, minor), NULL,
408 				 "phantom%u", minor)))
409 		dev_err(&pdev->dev, "can't create device\n");
410 
411 	pci_set_drvdata(pdev, pht);
412 
413 	return 0;
414 err_irq:
415 	free_irq(pdev->irq, pht);
416 err_unmo:
417 	pci_iounmap(pdev, pht->oaddr);
418 err_unmi:
419 	pci_iounmap(pdev, pht->iaddr);
420 err_unmc:
421 	pci_iounmap(pdev, pht->caddr);
422 err_fr:
423 	kfree(pht);
424 err_reg:
425 	pci_release_regions(pdev);
426 err_null:
427 	phantom_devices[minor] = 0;
428 err_dis:
429 	pci_disable_device(pdev);
430 err:
431 	return retval;
432 }
433 
434 static void phantom_remove(struct pci_dev *pdev)
435 {
436 	struct phantom_device *pht = pci_get_drvdata(pdev);
437 	unsigned int minor = MINOR(pht->cdev.dev);
438 
439 	device_destroy(phantom_class, MKDEV(phantom_major, minor));
440 
441 	cdev_del(&pht->cdev);
442 
443 	iowrite32(0, pht->caddr + PHN_IRQCTL);
444 	ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
445 	free_irq(pdev->irq, pht);
446 
447 	pci_iounmap(pdev, pht->oaddr);
448 	pci_iounmap(pdev, pht->iaddr);
449 	pci_iounmap(pdev, pht->caddr);
450 
451 	kfree(pht);
452 
453 	pci_release_regions(pdev);
454 
455 	phantom_devices[minor] = 0;
456 
457 	pci_disable_device(pdev);
458 }
459 
460 static int __maybe_unused phantom_suspend(struct device *dev_d)
461 {
462 	struct phantom_device *dev = dev_get_drvdata(dev_d);
463 
464 	iowrite32(0, dev->caddr + PHN_IRQCTL);
465 	ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
466 
467 	synchronize_irq(to_pci_dev(dev_d)->irq);
468 
469 	return 0;
470 }
471 
472 static int __maybe_unused phantom_resume(struct device *dev_d)
473 {
474 	struct phantom_device *dev = dev_get_drvdata(dev_d);
475 
476 	iowrite32(0, dev->caddr + PHN_IRQCTL);
477 
478 	return 0;
479 }
480 
481 static struct pci_device_id phantom_pci_tbl[] = {
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 SIMPLE_DEV_PM_OPS(phantom_pm_ops, phantom_suspend, phantom_resume);
490 
491 static struct pci_driver phantom_pci_driver = {
492 	.name = "phantom",
493 	.id_table = phantom_pci_tbl,
494 	.probe = phantom_probe,
495 	.remove = phantom_remove,
496 	.driver.pm = &phantom_pm_ops,
497 };
498 
499 static CLASS_ATTR_STRING(version, 0444, PHANTOM_VERSION);
500 
501 static int __init phantom_init(void)
502 {
503 	int retval;
504 	dev_t dev;
505 
506 	phantom_class = class_create("phantom");
507 	if (IS_ERR(phantom_class)) {
508 		retval = PTR_ERR(phantom_class);
509 		printk(KERN_ERR "phantom: can't register phantom class\n");
510 		goto err;
511 	}
512 	retval = class_create_file(phantom_class, &class_attr_version.attr);
513 	if (retval) {
514 		printk(KERN_ERR "phantom: can't create sysfs version file\n");
515 		goto err_class;
516 	}
517 
518 	retval = alloc_chrdev_region(&dev, 0, PHANTOM_MAX_MINORS, "phantom");
519 	if (retval) {
520 		printk(KERN_ERR "phantom: can't register character device\n");
521 		goto err_attr;
522 	}
523 	phantom_major = MAJOR(dev);
524 
525 	retval = pci_register_driver(&phantom_pci_driver);
526 	if (retval) {
527 		printk(KERN_ERR "phantom: can't register pci driver\n");
528 		goto err_unchr;
529 	}
530 
531 	printk(KERN_INFO "Phantom Linux Driver, version " PHANTOM_VERSION ", "
532 			"init OK\n");
533 
534 	return 0;
535 err_unchr:
536 	unregister_chrdev_region(dev, PHANTOM_MAX_MINORS);
537 err_attr:
538 	class_remove_file(phantom_class, &class_attr_version.attr);
539 err_class:
540 	class_destroy(phantom_class);
541 err:
542 	return retval;
543 }
544 
545 static void __exit phantom_exit(void)
546 {
547 	pci_unregister_driver(&phantom_pci_driver);
548 
549 	unregister_chrdev_region(MKDEV(phantom_major, 0), PHANTOM_MAX_MINORS);
550 
551 	class_remove_file(phantom_class, &class_attr_version.attr);
552 	class_destroy(phantom_class);
553 
554 	pr_debug("phantom: module successfully removed\n");
555 }
556 
557 module_init(phantom_init);
558 module_exit(phantom_exit);
559 
560 MODULE_AUTHOR("Jiri Slaby <jirislaby@gmail.com>");
561 MODULE_DESCRIPTION("Sensable Phantom driver (PCI devices)");
562 MODULE_LICENSE("GPL");
563 MODULE_VERSION(PHANTOM_VERSION);
564