xref: /openbmc/linux/drivers/misc/phantom.c (revision 64c70b1c)
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  */
13 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/device.h>
17 #include <linux/pci.h>
18 #include <linux/fs.h>
19 #include <linux/poll.h>
20 #include <linux/interrupt.h>
21 #include <linux/cdev.h>
22 #include <linux/phantom.h>
23 
24 #include <asm/atomic.h>
25 #include <asm/io.h>
26 
27 #define PHANTOM_VERSION		"n0.9.5"
28 
29 #define PHANTOM_MAX_MINORS	8
30 
31 #define PHN_IRQCTL		0x4c    /* irq control in caddr space */
32 
33 #define PHB_RUNNING		1
34 
35 static struct class *phantom_class;
36 static int phantom_major;
37 
38 struct phantom_device {
39 	unsigned int opened;
40 	void __iomem *caddr;
41 	u32 __iomem *iaddr;
42 	u32 __iomem *oaddr;
43 	unsigned long status;
44 	atomic_t counter;
45 
46 	wait_queue_head_t wait;
47 	struct cdev cdev;
48 
49 	struct mutex open_lock;
50 	spinlock_t ioctl_lock;
51 };
52 
53 static unsigned char phantom_devices[PHANTOM_MAX_MINORS];
54 
55 static int phantom_status(struct phantom_device *dev, unsigned long newstat)
56 {
57 	pr_debug("phantom_status %lx %lx\n", dev->status, newstat);
58 
59 	if (!(dev->status & PHB_RUNNING) && (newstat & PHB_RUNNING)) {
60 		atomic_set(&dev->counter, 0);
61 		iowrite32(PHN_CTL_IRQ, dev->iaddr + PHN_CONTROL);
62 		iowrite32(0x43, dev->caddr + PHN_IRQCTL);
63 		ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
64 	} else if ((dev->status & PHB_RUNNING) && !(newstat & PHB_RUNNING)) {
65 		iowrite32(0, dev->caddr + PHN_IRQCTL);
66 		ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
67 	}
68 
69 	dev->status = newstat;
70 
71 	return 0;
72 }
73 
74 /*
75  * File ops
76  */
77 
78 static long phantom_ioctl(struct file *file, unsigned int cmd,
79 		unsigned long arg)
80 {
81 	struct phantom_device *dev = file->private_data;
82 	struct phm_regs rs;
83 	struct phm_reg r;
84 	void __user *argp = (void __user *)arg;
85 	unsigned int i;
86 
87 	if (_IOC_TYPE(cmd) != PH_IOC_MAGIC ||
88 			_IOC_NR(cmd) > PH_IOC_MAXNR)
89 		return -ENOTTY;
90 
91 	switch (cmd) {
92 	case PHN_SET_REG:
93 		if (copy_from_user(&r, argp, sizeof(r)))
94 			return -EFAULT;
95 
96 		if (r.reg > 7)
97 			return -EINVAL;
98 
99 		spin_lock(&dev->ioctl_lock);
100 		if (r.reg == PHN_CONTROL && (r.value & PHN_CTL_IRQ) &&
101 				phantom_status(dev, dev->status | PHB_RUNNING)){
102 			spin_unlock(&dev->ioctl_lock);
103 			return -ENODEV;
104 		}
105 
106 		pr_debug("phantom: writing %x to %u\n", r.value, r.reg);
107 		iowrite32(r.value, dev->iaddr + r.reg);
108 		ioread32(dev->iaddr); /* PCI posting */
109 
110 		if (r.reg == PHN_CONTROL && !(r.value & PHN_CTL_IRQ))
111 			phantom_status(dev, dev->status & ~PHB_RUNNING);
112 		spin_unlock(&dev->ioctl_lock);
113 		break;
114 	case PHN_SET_REGS:
115 		if (copy_from_user(&rs, argp, sizeof(rs)))
116 			return -EFAULT;
117 
118 		pr_debug("phantom: SRS %u regs %x\n", rs.count, rs.mask);
119 		spin_lock(&dev->ioctl_lock);
120 		for (i = 0; i < min(rs.count, 8U); i++)
121 			if ((1 << i) & rs.mask)
122 				iowrite32(rs.values[i], dev->oaddr + i);
123 		ioread32(dev->iaddr); /* PCI posting */
124 		spin_unlock(&dev->ioctl_lock);
125 		break;
126 	case PHN_GET_REG:
127 		if (copy_from_user(&r, argp, sizeof(r)))
128 			return -EFAULT;
129 
130 		if (r.reg > 7)
131 			return -EINVAL;
132 
133 		r.value = ioread32(dev->iaddr + r.reg);
134 
135 		if (copy_to_user(argp, &r, sizeof(r)))
136 			return -EFAULT;
137 		break;
138 	case PHN_GET_REGS:
139 		if (copy_from_user(&rs, argp, sizeof(rs)))
140 			return -EFAULT;
141 
142 		pr_debug("phantom: GRS %u regs %x\n", rs.count, rs.mask);
143 		spin_lock(&dev->ioctl_lock);
144 		for (i = 0; i < min(rs.count, 8U); i++)
145 			if ((1 << i) & rs.mask)
146 				rs.values[i] = ioread32(dev->iaddr + i);
147 		spin_unlock(&dev->ioctl_lock);
148 
149 		if (copy_to_user(argp, &rs, sizeof(rs)))
150 			return -EFAULT;
151 		break;
152 	default:
153 		return -ENOTTY;
154 	}
155 
156 	return 0;
157 }
158 
159 static int phantom_open(struct inode *inode, struct file *file)
160 {
161 	struct phantom_device *dev = container_of(inode->i_cdev,
162 			struct phantom_device, cdev);
163 
164 	nonseekable_open(inode, file);
165 
166 	if (mutex_lock_interruptible(&dev->open_lock))
167 		return -ERESTARTSYS;
168 
169 	if (dev->opened) {
170 		mutex_unlock(&dev->open_lock);
171 		return -EINVAL;
172 	}
173 
174 	file->private_data = dev;
175 
176 	dev->opened++;
177 	mutex_unlock(&dev->open_lock);
178 
179 	return 0;
180 }
181 
182 static int phantom_release(struct inode *inode, struct file *file)
183 {
184 	struct phantom_device *dev = file->private_data;
185 
186 	mutex_lock(&dev->open_lock);
187 
188 	dev->opened = 0;
189 	phantom_status(dev, dev->status & ~PHB_RUNNING);
190 
191 	mutex_unlock(&dev->open_lock);
192 
193 	return 0;
194 }
195 
196 static unsigned int phantom_poll(struct file *file, poll_table *wait)
197 {
198 	struct phantom_device *dev = file->private_data;
199 	unsigned int mask = 0;
200 
201 	pr_debug("phantom_poll: %d\n", atomic_read(&dev->counter));
202 	poll_wait(file, &dev->wait, wait);
203 	if (atomic_read(&dev->counter)) {
204 		mask = POLLIN | POLLRDNORM;
205 		atomic_dec(&dev->counter);
206 	} else if ((dev->status & PHB_RUNNING) == 0)
207 		mask = POLLIN | POLLRDNORM | POLLERR;
208 	pr_debug("phantom_poll end: %x/%d\n", mask, atomic_read(&dev->counter));
209 
210 	return mask;
211 }
212 
213 static struct file_operations phantom_file_ops = {
214 	.open = phantom_open,
215 	.release = phantom_release,
216 	.unlocked_ioctl = phantom_ioctl,
217 	.poll = phantom_poll,
218 };
219 
220 static irqreturn_t phantom_isr(int irq, void *data)
221 {
222 	struct phantom_device *dev = data;
223 
224 	if (!(ioread32(dev->iaddr + PHN_CONTROL) & PHN_CTL_IRQ))
225 		return IRQ_NONE;
226 
227 	iowrite32(0, dev->iaddr);
228 	iowrite32(0xc0, dev->iaddr);
229 	ioread32(dev->iaddr); /* PCI posting */
230 
231 	atomic_inc(&dev->counter);
232 	wake_up_interruptible(&dev->wait);
233 
234 	return IRQ_HANDLED;
235 }
236 
237 /*
238  * Init and deinit driver
239  */
240 
241 static unsigned int __devinit phantom_get_free(void)
242 {
243 	unsigned int i;
244 
245 	for (i = 0; i < PHANTOM_MAX_MINORS; i++)
246 		if (phantom_devices[i] == 0)
247 			break;
248 
249 	return i;
250 }
251 
252 static int __devinit phantom_probe(struct pci_dev *pdev,
253 	const struct pci_device_id *pci_id)
254 {
255 	struct phantom_device *pht;
256 	unsigned int minor;
257 	int retval;
258 
259 	retval = pci_enable_device(pdev);
260 	if (retval)
261 		goto err;
262 
263 	minor = phantom_get_free();
264 	if (minor == PHANTOM_MAX_MINORS) {
265 		dev_err(&pdev->dev, "too many devices found!\n");
266 		retval = -EIO;
267 		goto err_dis;
268 	}
269 
270 	phantom_devices[minor] = 1;
271 
272 	retval = pci_request_regions(pdev, "phantom");
273 	if (retval)
274 		goto err_null;
275 
276 	retval = -ENOMEM;
277 	pht = kzalloc(sizeof(*pht), GFP_KERNEL);
278 	if (pht == NULL) {
279 		dev_err(&pdev->dev, "unable to allocate device\n");
280 		goto err_reg;
281 	}
282 
283 	pht->caddr = pci_iomap(pdev, 0, 0);
284 	if (pht->caddr == NULL) {
285 		dev_err(&pdev->dev, "can't remap conf space\n");
286 		goto err_fr;
287 	}
288 	pht->iaddr = pci_iomap(pdev, 2, 0);
289 	if (pht->iaddr == NULL) {
290 		dev_err(&pdev->dev, "can't remap input space\n");
291 		goto err_unmc;
292 	}
293 	pht->oaddr = pci_iomap(pdev, 3, 0);
294 	if (pht->oaddr == NULL) {
295 		dev_err(&pdev->dev, "can't remap output space\n");
296 		goto err_unmi;
297 	}
298 
299 	mutex_init(&pht->open_lock);
300 	spin_lock_init(&pht->ioctl_lock);
301 	init_waitqueue_head(&pht->wait);
302 	cdev_init(&pht->cdev, &phantom_file_ops);
303 	pht->cdev.owner = THIS_MODULE;
304 
305 	iowrite32(0, pht->caddr + PHN_IRQCTL);
306 	ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
307 	retval = request_irq(pdev->irq, phantom_isr,
308 			IRQF_SHARED | IRQF_DISABLED, "phantom", pht);
309 	if (retval) {
310 		dev_err(&pdev->dev, "can't establish ISR\n");
311 		goto err_unmo;
312 	}
313 
314 	retval = cdev_add(&pht->cdev, MKDEV(phantom_major, minor), 1);
315 	if (retval) {
316 		dev_err(&pdev->dev, "chardev registration failed\n");
317 		goto err_irq;
318 	}
319 
320 	if (IS_ERR(device_create(phantom_class, &pdev->dev, MKDEV(phantom_major,
321 			minor), "phantom%u", minor)))
322 		dev_err(&pdev->dev, "can't create device\n");
323 
324 	pci_set_drvdata(pdev, pht);
325 
326 	return 0;
327 err_irq:
328 	free_irq(pdev->irq, pht);
329 err_unmo:
330 	pci_iounmap(pdev, pht->oaddr);
331 err_unmi:
332 	pci_iounmap(pdev, pht->iaddr);
333 err_unmc:
334 	pci_iounmap(pdev, pht->caddr);
335 err_fr:
336 	kfree(pht);
337 err_reg:
338 	pci_release_regions(pdev);
339 err_null:
340 	phantom_devices[minor] = 0;
341 err_dis:
342 	pci_disable_device(pdev);
343 err:
344 	return retval;
345 }
346 
347 static void __devexit phantom_remove(struct pci_dev *pdev)
348 {
349 	struct phantom_device *pht = pci_get_drvdata(pdev);
350 	unsigned int minor = MINOR(pht->cdev.dev);
351 
352 	device_destroy(phantom_class, MKDEV(phantom_major, minor));
353 
354 	cdev_del(&pht->cdev);
355 
356 	iowrite32(0, pht->caddr + PHN_IRQCTL);
357 	ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
358 	free_irq(pdev->irq, pht);
359 
360 	pci_iounmap(pdev, pht->oaddr);
361 	pci_iounmap(pdev, pht->iaddr);
362 	pci_iounmap(pdev, pht->caddr);
363 
364 	kfree(pht);
365 
366 	pci_release_regions(pdev);
367 
368 	phantom_devices[minor] = 0;
369 
370 	pci_disable_device(pdev);
371 }
372 
373 #ifdef CONFIG_PM
374 static int phantom_suspend(struct pci_dev *pdev, pm_message_t state)
375 {
376 	struct phantom_device *dev = pci_get_drvdata(pdev);
377 
378 	iowrite32(0, dev->caddr + PHN_IRQCTL);
379 	ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
380 
381 	return 0;
382 }
383 
384 static int phantom_resume(struct pci_dev *pdev)
385 {
386 	struct phantom_device *dev = pci_get_drvdata(pdev);
387 
388 	iowrite32(0, dev->caddr + PHN_IRQCTL);
389 
390 	return 0;
391 }
392 #else
393 #define phantom_suspend	NULL
394 #define phantom_resume	NULL
395 #endif
396 
397 static struct pci_device_id phantom_pci_tbl[] __devinitdata = {
398 	{ PCI_DEVICE(PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9050),
399 		.class = PCI_CLASS_BRIDGE_OTHER << 8, .class_mask = 0xffff00 },
400 	{ 0, }
401 };
402 MODULE_DEVICE_TABLE(pci, phantom_pci_tbl);
403 
404 static struct pci_driver phantom_pci_driver = {
405 	.name = "phantom",
406 	.id_table = phantom_pci_tbl,
407 	.probe = phantom_probe,
408 	.remove = __devexit_p(phantom_remove),
409 	.suspend = phantom_suspend,
410 	.resume = phantom_resume
411 };
412 
413 static ssize_t phantom_show_version(struct class *cls, char *buf)
414 {
415 	return sprintf(buf, PHANTOM_VERSION "\n");
416 }
417 
418 static CLASS_ATTR(version, 0444, phantom_show_version, NULL);
419 
420 static int __init phantom_init(void)
421 {
422 	int retval;
423 	dev_t dev;
424 
425 	phantom_class = class_create(THIS_MODULE, "phantom");
426 	if (IS_ERR(phantom_class)) {
427 		retval = PTR_ERR(phantom_class);
428 		printk(KERN_ERR "phantom: can't register phantom class\n");
429 		goto err;
430 	}
431 	retval = class_create_file(phantom_class, &class_attr_version);
432 	if (retval) {
433 		printk(KERN_ERR "phantom: can't create sysfs version file\n");
434 		goto err_class;
435 	}
436 
437 	retval = alloc_chrdev_region(&dev, 0, PHANTOM_MAX_MINORS, "phantom");
438 	if (retval) {
439 		printk(KERN_ERR "phantom: can't register character device\n");
440 		goto err_attr;
441 	}
442 	phantom_major = MAJOR(dev);
443 
444 	retval = pci_register_driver(&phantom_pci_driver);
445 	if (retval) {
446 		printk(KERN_ERR "phantom: can't register pci driver\n");
447 		goto err_unchr;
448 	}
449 
450 	printk(KERN_INFO "Phantom Linux Driver, version " PHANTOM_VERSION ", "
451 			"init OK\n");
452 
453 	return 0;
454 err_unchr:
455 	unregister_chrdev_region(dev, PHANTOM_MAX_MINORS);
456 err_attr:
457 	class_remove_file(phantom_class, &class_attr_version);
458 err_class:
459 	class_destroy(phantom_class);
460 err:
461 	return retval;
462 }
463 
464 static void __exit phantom_exit(void)
465 {
466 	pci_unregister_driver(&phantom_pci_driver);
467 
468 	unregister_chrdev_region(MKDEV(phantom_major, 0), PHANTOM_MAX_MINORS);
469 
470 	class_remove_file(phantom_class, &class_attr_version);
471 	class_destroy(phantom_class);
472 
473 	pr_debug("phantom: module successfully removed\n");
474 }
475 
476 module_init(phantom_init);
477 module_exit(phantom_exit);
478 
479 MODULE_AUTHOR("Jiri Slaby <jirislaby@gmail.com>");
480 MODULE_DESCRIPTION("Sensable Phantom driver");
481 MODULE_LICENSE("GPL");
482 MODULE_VERSION(PHANTOM_VERSION);
483