xref: /openbmc/linux/drivers/misc/phantom.c (revision d0e22329)
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 a 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/slab.h>
25 #include <linux/phantom.h>
26 #include <linux/sched.h>
27 #include <linux/mutex.h>
28 
29 #include <linux/atomic.h>
30 #include <asm/io.h>
31 
32 #define PHANTOM_VERSION		"n0.9.8"
33 
34 #define PHANTOM_MAX_MINORS	8
35 
36 #define PHN_IRQCTL		0x4c    /* irq control in caddr space */
37 
38 #define PHB_RUNNING		1
39 #define PHB_NOT_OH		2
40 
41 static DEFINE_MUTEX(phantom_mutex);
42 static struct class *phantom_class;
43 static int phantom_major;
44 
45 struct phantom_device {
46 	unsigned int opened;
47 	void __iomem *caddr;
48 	u32 __iomem *iaddr;
49 	u32 __iomem *oaddr;
50 	unsigned long status;
51 	atomic_t counter;
52 
53 	wait_queue_head_t wait;
54 	struct cdev cdev;
55 
56 	struct mutex open_lock;
57 	spinlock_t regs_lock;
58 
59 	/* used in NOT_OH mode */
60 	struct phm_regs oregs;
61 	u32 ctl_reg;
62 };
63 
64 static unsigned char phantom_devices[PHANTOM_MAX_MINORS];
65 
66 static int phantom_status(struct phantom_device *dev, unsigned long newstat)
67 {
68 	pr_debug("phantom_status %lx %lx\n", dev->status, newstat);
69 
70 	if (!(dev->status & PHB_RUNNING) && (newstat & PHB_RUNNING)) {
71 		atomic_set(&dev->counter, 0);
72 		iowrite32(PHN_CTL_IRQ, dev->iaddr + PHN_CONTROL);
73 		iowrite32(0x43, dev->caddr + PHN_IRQCTL);
74 		ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
75 	} else if ((dev->status & PHB_RUNNING) && !(newstat & PHB_RUNNING)) {
76 		iowrite32(0, dev->caddr + PHN_IRQCTL);
77 		ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
78 	}
79 
80 	dev->status = newstat;
81 
82 	return 0;
83 }
84 
85 /*
86  * File ops
87  */
88 
89 static long phantom_ioctl(struct file *file, unsigned int cmd,
90 		unsigned long arg)
91 {
92 	struct phantom_device *dev = file->private_data;
93 	struct phm_regs rs;
94 	struct phm_reg r;
95 	void __user *argp = (void __user *)arg;
96 	unsigned long flags;
97 	unsigned int i;
98 
99 	switch (cmd) {
100 	case PHN_SETREG:
101 	case PHN_SET_REG:
102 		if (copy_from_user(&r, argp, sizeof(r)))
103 			return -EFAULT;
104 
105 		if (r.reg > 7)
106 			return -EINVAL;
107 
108 		spin_lock_irqsave(&dev->regs_lock, flags);
109 		if (r.reg == PHN_CONTROL && (r.value & PHN_CTL_IRQ) &&
110 				phantom_status(dev, dev->status | PHB_RUNNING)){
111 			spin_unlock_irqrestore(&dev->regs_lock, flags);
112 			return -ENODEV;
113 		}
114 
115 		pr_debug("phantom: writing %x to %u\n", r.value, r.reg);
116 
117 		/* preserve amp bit (don't allow to change it when in NOT_OH) */
118 		if (r.reg == PHN_CONTROL && (dev->status & PHB_NOT_OH)) {
119 			r.value &= ~PHN_CTL_AMP;
120 			r.value |= dev->ctl_reg & PHN_CTL_AMP;
121 			dev->ctl_reg = r.value;
122 		}
123 
124 		iowrite32(r.value, dev->iaddr + r.reg);
125 		ioread32(dev->iaddr); /* PCI posting */
126 
127 		if (r.reg == PHN_CONTROL && !(r.value & PHN_CTL_IRQ))
128 			phantom_status(dev, dev->status & ~PHB_RUNNING);
129 		spin_unlock_irqrestore(&dev->regs_lock, flags);
130 		break;
131 	case PHN_SETREGS:
132 	case PHN_SET_REGS:
133 		if (copy_from_user(&rs, argp, sizeof(rs)))
134 			return -EFAULT;
135 
136 		pr_debug("phantom: SRS %u regs %x\n", rs.count, rs.mask);
137 		spin_lock_irqsave(&dev->regs_lock, flags);
138 		if (dev->status & PHB_NOT_OH)
139 			memcpy(&dev->oregs, &rs, sizeof(rs));
140 		else {
141 			u32 m = min(rs.count, 8U);
142 			for (i = 0; i < m; i++)
143 				if (rs.mask & BIT(i))
144 					iowrite32(rs.values[i], dev->oaddr + i);
145 			ioread32(dev->iaddr); /* PCI posting */
146 		}
147 		spin_unlock_irqrestore(&dev->regs_lock, flags);
148 		break;
149 	case PHN_GETREG:
150 	case PHN_GET_REG:
151 		if (copy_from_user(&r, argp, sizeof(r)))
152 			return -EFAULT;
153 
154 		if (r.reg > 7)
155 			return -EINVAL;
156 
157 		r.value = ioread32(dev->iaddr + r.reg);
158 
159 		if (copy_to_user(argp, &r, sizeof(r)))
160 			return -EFAULT;
161 		break;
162 	case PHN_GETREGS:
163 	case PHN_GET_REGS: {
164 		u32 m;
165 
166 		if (copy_from_user(&rs, argp, sizeof(rs)))
167 			return -EFAULT;
168 
169 		m = min(rs.count, 8U);
170 
171 		pr_debug("phantom: GRS %u regs %x\n", rs.count, rs.mask);
172 		spin_lock_irqsave(&dev->regs_lock, flags);
173 		for (i = 0; i < m; i++)
174 			if (rs.mask & BIT(i))
175 				rs.values[i] = ioread32(dev->iaddr + i);
176 		atomic_set(&dev->counter, 0);
177 		spin_unlock_irqrestore(&dev->regs_lock, flags);
178 
179 		if (copy_to_user(argp, &rs, sizeof(rs)))
180 			return -EFAULT;
181 		break;
182 	} case PHN_NOT_OH:
183 		spin_lock_irqsave(&dev->regs_lock, flags);
184 		if (dev->status & PHB_RUNNING) {
185 			printk(KERN_ERR "phantom: you need to set NOT_OH "
186 					"before you start the device!\n");
187 			spin_unlock_irqrestore(&dev->regs_lock, flags);
188 			return -EINVAL;
189 		}
190 		dev->status |= PHB_NOT_OH;
191 		spin_unlock_irqrestore(&dev->regs_lock, flags);
192 		break;
193 	default:
194 		return -ENOTTY;
195 	}
196 
197 	return 0;
198 }
199 
200 #ifdef CONFIG_COMPAT
201 static long phantom_compat_ioctl(struct file *filp, unsigned int cmd,
202 		unsigned long arg)
203 {
204 	if (_IOC_NR(cmd) <= 3 && _IOC_SIZE(cmd) == sizeof(compat_uptr_t)) {
205 		cmd &= ~(_IOC_SIZEMASK << _IOC_SIZESHIFT);
206 		cmd |= sizeof(void *) << _IOC_SIZESHIFT;
207 	}
208 	return phantom_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
209 }
210 #else
211 #define phantom_compat_ioctl NULL
212 #endif
213 
214 static int phantom_open(struct inode *inode, struct file *file)
215 {
216 	struct phantom_device *dev = container_of(inode->i_cdev,
217 			struct phantom_device, cdev);
218 
219 	mutex_lock(&phantom_mutex);
220 	nonseekable_open(inode, file);
221 
222 	if (mutex_lock_interruptible(&dev->open_lock)) {
223 		mutex_unlock(&phantom_mutex);
224 		return -ERESTARTSYS;
225 	}
226 
227 	if (dev->opened) {
228 		mutex_unlock(&dev->open_lock);
229 		mutex_unlock(&phantom_mutex);
230 		return -EINVAL;
231 	}
232 
233 	WARN_ON(dev->status & PHB_NOT_OH);
234 
235 	file->private_data = dev;
236 
237 	atomic_set(&dev->counter, 0);
238 	dev->opened++;
239 	mutex_unlock(&dev->open_lock);
240 	mutex_unlock(&phantom_mutex);
241 	return 0;
242 }
243 
244 static int phantom_release(struct inode *inode, struct file *file)
245 {
246 	struct phantom_device *dev = file->private_data;
247 
248 	mutex_lock(&dev->open_lock);
249 
250 	dev->opened = 0;
251 	phantom_status(dev, dev->status & ~PHB_RUNNING);
252 	dev->status &= ~PHB_NOT_OH;
253 
254 	mutex_unlock(&dev->open_lock);
255 
256 	return 0;
257 }
258 
259 static __poll_t phantom_poll(struct file *file, poll_table *wait)
260 {
261 	struct phantom_device *dev = file->private_data;
262 	__poll_t mask = 0;
263 
264 	pr_debug("phantom_poll: %d\n", atomic_read(&dev->counter));
265 	poll_wait(file, &dev->wait, wait);
266 
267 	if (!(dev->status & PHB_RUNNING))
268 		mask = EPOLLERR;
269 	else if (atomic_read(&dev->counter))
270 		mask = EPOLLIN | EPOLLRDNORM;
271 
272 	pr_debug("phantom_poll end: %x/%d\n", mask, atomic_read(&dev->counter));
273 
274 	return mask;
275 }
276 
277 static const struct file_operations phantom_file_ops = {
278 	.open = phantom_open,
279 	.release = phantom_release,
280 	.unlocked_ioctl = phantom_ioctl,
281 	.compat_ioctl = phantom_compat_ioctl,
282 	.poll = phantom_poll,
283 	.llseek = no_llseek,
284 };
285 
286 static irqreturn_t phantom_isr(int irq, void *data)
287 {
288 	struct phantom_device *dev = data;
289 	unsigned int i;
290 	u32 ctl;
291 
292 	spin_lock(&dev->regs_lock);
293 	ctl = ioread32(dev->iaddr + PHN_CONTROL);
294 	if (!(ctl & PHN_CTL_IRQ)) {
295 		spin_unlock(&dev->regs_lock);
296 		return IRQ_NONE;
297 	}
298 
299 	iowrite32(0, dev->iaddr);
300 	iowrite32(0xc0, dev->iaddr);
301 
302 	if (dev->status & PHB_NOT_OH) {
303 		struct phm_regs *r = &dev->oregs;
304 		u32 m = min(r->count, 8U);
305 
306 		for (i = 0; i < m; i++)
307 			if (r->mask & BIT(i))
308 				iowrite32(r->values[i], dev->oaddr + i);
309 
310 		dev->ctl_reg ^= PHN_CTL_AMP;
311 		iowrite32(dev->ctl_reg, dev->iaddr + PHN_CONTROL);
312 	}
313 	spin_unlock(&dev->regs_lock);
314 
315 	ioread32(dev->iaddr); /* PCI posting */
316 
317 	atomic_inc(&dev->counter);
318 	wake_up_interruptible(&dev->wait);
319 
320 	return IRQ_HANDLED;
321 }
322 
323 /*
324  * Init and deinit driver
325  */
326 
327 static unsigned int phantom_get_free(void)
328 {
329 	unsigned int i;
330 
331 	for (i = 0; i < PHANTOM_MAX_MINORS; i++)
332 		if (phantom_devices[i] == 0)
333 			break;
334 
335 	return i;
336 }
337 
338 static int phantom_probe(struct pci_dev *pdev,
339 	const struct pci_device_id *pci_id)
340 {
341 	struct phantom_device *pht;
342 	unsigned int minor;
343 	int retval;
344 
345 	retval = pci_enable_device(pdev);
346 	if (retval) {
347 		dev_err(&pdev->dev, "pci_enable_device failed!\n");
348 		goto err;
349 	}
350 
351 	minor = phantom_get_free();
352 	if (minor == PHANTOM_MAX_MINORS) {
353 		dev_err(&pdev->dev, "too many devices found!\n");
354 		retval = -EIO;
355 		goto err_dis;
356 	}
357 
358 	phantom_devices[minor] = 1;
359 
360 	retval = pci_request_regions(pdev, "phantom");
361 	if (retval) {
362 		dev_err(&pdev->dev, "pci_request_regions failed!\n");
363 		goto err_null;
364 	}
365 
366 	retval = -ENOMEM;
367 	pht = kzalloc(sizeof(*pht), GFP_KERNEL);
368 	if (pht == NULL) {
369 		dev_err(&pdev->dev, "unable to allocate device\n");
370 		goto err_reg;
371 	}
372 
373 	pht->caddr = pci_iomap(pdev, 0, 0);
374 	if (pht->caddr == NULL) {
375 		dev_err(&pdev->dev, "can't remap conf space\n");
376 		goto err_fr;
377 	}
378 	pht->iaddr = pci_iomap(pdev, 2, 0);
379 	if (pht->iaddr == NULL) {
380 		dev_err(&pdev->dev, "can't remap input space\n");
381 		goto err_unmc;
382 	}
383 	pht->oaddr = pci_iomap(pdev, 3, 0);
384 	if (pht->oaddr == NULL) {
385 		dev_err(&pdev->dev, "can't remap output space\n");
386 		goto err_unmi;
387 	}
388 
389 	mutex_init(&pht->open_lock);
390 	spin_lock_init(&pht->regs_lock);
391 	init_waitqueue_head(&pht->wait);
392 	cdev_init(&pht->cdev, &phantom_file_ops);
393 	pht->cdev.owner = THIS_MODULE;
394 
395 	iowrite32(0, pht->caddr + PHN_IRQCTL);
396 	ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
397 	retval = request_irq(pdev->irq, phantom_isr,
398 			IRQF_SHARED, "phantom", pht);
399 	if (retval) {
400 		dev_err(&pdev->dev, "can't establish ISR\n");
401 		goto err_unmo;
402 	}
403 
404 	retval = cdev_add(&pht->cdev, MKDEV(phantom_major, minor), 1);
405 	if (retval) {
406 		dev_err(&pdev->dev, "chardev registration failed\n");
407 		goto err_irq;
408 	}
409 
410 	if (IS_ERR(device_create(phantom_class, &pdev->dev,
411 				 MKDEV(phantom_major, minor), NULL,
412 				 "phantom%u", minor)))
413 		dev_err(&pdev->dev, "can't create device\n");
414 
415 	pci_set_drvdata(pdev, pht);
416 
417 	return 0;
418 err_irq:
419 	free_irq(pdev->irq, pht);
420 err_unmo:
421 	pci_iounmap(pdev, pht->oaddr);
422 err_unmi:
423 	pci_iounmap(pdev, pht->iaddr);
424 err_unmc:
425 	pci_iounmap(pdev, pht->caddr);
426 err_fr:
427 	kfree(pht);
428 err_reg:
429 	pci_release_regions(pdev);
430 err_null:
431 	phantom_devices[minor] = 0;
432 err_dis:
433 	pci_disable_device(pdev);
434 err:
435 	return retval;
436 }
437 
438 static void phantom_remove(struct pci_dev *pdev)
439 {
440 	struct phantom_device *pht = pci_get_drvdata(pdev);
441 	unsigned int minor = MINOR(pht->cdev.dev);
442 
443 	device_destroy(phantom_class, MKDEV(phantom_major, minor));
444 
445 	cdev_del(&pht->cdev);
446 
447 	iowrite32(0, pht->caddr + PHN_IRQCTL);
448 	ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
449 	free_irq(pdev->irq, pht);
450 
451 	pci_iounmap(pdev, pht->oaddr);
452 	pci_iounmap(pdev, pht->iaddr);
453 	pci_iounmap(pdev, pht->caddr);
454 
455 	kfree(pht);
456 
457 	pci_release_regions(pdev);
458 
459 	phantom_devices[minor] = 0;
460 
461 	pci_disable_device(pdev);
462 }
463 
464 #ifdef CONFIG_PM
465 static int phantom_suspend(struct pci_dev *pdev, pm_message_t state)
466 {
467 	struct phantom_device *dev = pci_get_drvdata(pdev);
468 
469 	iowrite32(0, dev->caddr + PHN_IRQCTL);
470 	ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
471 
472 	synchronize_irq(pdev->irq);
473 
474 	return 0;
475 }
476 
477 static int phantom_resume(struct pci_dev *pdev)
478 {
479 	struct phantom_device *dev = pci_get_drvdata(pdev);
480 
481 	iowrite32(0, dev->caddr + PHN_IRQCTL);
482 
483 	return 0;
484 }
485 #else
486 #define phantom_suspend	NULL
487 #define phantom_resume	NULL
488 #endif
489 
490 static struct pci_device_id phantom_pci_tbl[] = {
491 	{ .vendor = PCI_VENDOR_ID_PLX, .device = PCI_DEVICE_ID_PLX_9050,
492 	  .subvendor = PCI_VENDOR_ID_PLX, .subdevice = PCI_DEVICE_ID_PLX_9050,
493 	  .class = PCI_CLASS_BRIDGE_OTHER << 8, .class_mask = 0xffff00 },
494 	{ 0, }
495 };
496 MODULE_DEVICE_TABLE(pci, phantom_pci_tbl);
497 
498 static struct pci_driver phantom_pci_driver = {
499 	.name = "phantom",
500 	.id_table = phantom_pci_tbl,
501 	.probe = phantom_probe,
502 	.remove = phantom_remove,
503 	.suspend = phantom_suspend,
504 	.resume = phantom_resume
505 };
506 
507 static CLASS_ATTR_STRING(version, 0444, PHANTOM_VERSION);
508 
509 static int __init phantom_init(void)
510 {
511 	int retval;
512 	dev_t dev;
513 
514 	phantom_class = class_create(THIS_MODULE, "phantom");
515 	if (IS_ERR(phantom_class)) {
516 		retval = PTR_ERR(phantom_class);
517 		printk(KERN_ERR "phantom: can't register phantom class\n");
518 		goto err;
519 	}
520 	retval = class_create_file(phantom_class, &class_attr_version.attr);
521 	if (retval) {
522 		printk(KERN_ERR "phantom: can't create sysfs version file\n");
523 		goto err_class;
524 	}
525 
526 	retval = alloc_chrdev_region(&dev, 0, PHANTOM_MAX_MINORS, "phantom");
527 	if (retval) {
528 		printk(KERN_ERR "phantom: can't register character device\n");
529 		goto err_attr;
530 	}
531 	phantom_major = MAJOR(dev);
532 
533 	retval = pci_register_driver(&phantom_pci_driver);
534 	if (retval) {
535 		printk(KERN_ERR "phantom: can't register pci driver\n");
536 		goto err_unchr;
537 	}
538 
539 	printk(KERN_INFO "Phantom Linux Driver, version " PHANTOM_VERSION ", "
540 			"init OK\n");
541 
542 	return 0;
543 err_unchr:
544 	unregister_chrdev_region(dev, PHANTOM_MAX_MINORS);
545 err_attr:
546 	class_remove_file(phantom_class, &class_attr_version.attr);
547 err_class:
548 	class_destroy(phantom_class);
549 err:
550 	return retval;
551 }
552 
553 static void __exit phantom_exit(void)
554 {
555 	pci_unregister_driver(&phantom_pci_driver);
556 
557 	unregister_chrdev_region(MKDEV(phantom_major, 0), PHANTOM_MAX_MINORS);
558 
559 	class_remove_file(phantom_class, &class_attr_version.attr);
560 	class_destroy(phantom_class);
561 
562 	pr_debug("phantom: module successfully removed\n");
563 }
564 
565 module_init(phantom_init);
566 module_exit(phantom_exit);
567 
568 MODULE_AUTHOR("Jiri Slaby <jirislaby@gmail.com>");
569 MODULE_DESCRIPTION("Sensable Phantom driver (PCI devices)");
570 MODULE_LICENSE("GPL");
571 MODULE_VERSION(PHANTOM_VERSION);
572