xref: /linux/drivers/firewire/nosy.c (revision 1c55bc8710a3ce9f93a35c6376706ae3eec71749)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * nosy - Snoop mode driver for TI PCILynx 1394 controllers
4  * Copyright (C) 2002-2007 Kristian Høgsberg
5  */
6 
7 #include <linux/device.h>
8 #include <linux/errno.h>
9 #include <linux/fs.h>
10 #include <linux/init.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/kernel.h>
14 #include <linux/kref.h>
15 #include <linux/miscdevice.h>
16 #include <linux/module.h>
17 #include <linux/mutex.h>
18 #include <linux/pci.h>
19 #include <linux/poll.h>
20 #include <linux/sched.h> /* required for linux/wait.h */
21 #include <linux/slab.h>
22 #include <linux/spinlock.h>
23 #include <linux/time64.h>
24 #include <linux/timex.h>
25 #include <linux/uaccess.h>
26 #include <linux/wait.h>
27 #include <linux/dma-mapping.h>
28 #include <linux/atomic.h>
29 #include <asm/byteorder.h>
30 
31 #include "nosy.h"
32 #include "nosy-user.h"
33 
34 #define TCODE_PHY_PACKET		0x10
35 #define PCI_DEVICE_ID_TI_PCILYNX	0x8000
36 
37 static char driver_name[] = KBUILD_MODNAME;
38 
39 #define RCV_BUFFER_SIZE (16 * 1024)
40 
41 /* this is the physical layout of a PCL, its size is 128 bytes */
42 struct pcl {
43 	__le32 next;
44 	__le32 async_error_next;
45 	u32 user_data;
46 	__le32 pcl_status;
47 	__le32 remaining_transfer_count;
48 	__le32 next_data_buffer;
49 	struct {
50 		__le32 control;
51 		__le32 pointer;
52 	} buffer[13];
53 };
54 
55 struct packet {
56 	unsigned int length;
57 	char data[];
58 };
59 
60 struct packet_buffer {
61 	char *data;
62 	size_t capacity;
63 	long total_packet_count, lost_packet_count;
64 	atomic_t size;
65 	struct packet *head, *tail;
66 	wait_queue_head_t wait;
67 };
68 
69 struct pcilynx {
70 	struct pci_dev *pci_device;
71 	__iomem char *registers;
72 
73 	struct pcl *rcv_start_pcl, *rcv_pcl;
74 	__le32 *rcv_buffer;
75 
76 	dma_addr_t rcv_start_pcl_bus, rcv_pcl_bus, rcv_buffer_bus;
77 
78 	spinlock_t client_list_lock;
79 	struct list_head client_list;
80 
81 	struct miscdevice misc;
82 	struct list_head link;
83 	struct kref kref;
84 };
85 
86 static inline struct pcilynx *
lynx_get(struct pcilynx * lynx)87 lynx_get(struct pcilynx *lynx)
88 {
89 	kref_get(&lynx->kref);
90 
91 	return lynx;
92 }
93 
94 static void
lynx_release(struct kref * kref)95 lynx_release(struct kref *kref)
96 {
97 	kfree(container_of(kref, struct pcilynx, kref));
98 }
99 
100 static inline void
lynx_put(struct pcilynx * lynx)101 lynx_put(struct pcilynx *lynx)
102 {
103 	kref_put(&lynx->kref, lynx_release);
104 }
105 
106 struct client {
107 	struct pcilynx *lynx;
108 	u32 tcode_mask;
109 	struct packet_buffer buffer;
110 	struct list_head link;
111 };
112 
113 static DEFINE_MUTEX(card_mutex);
114 static LIST_HEAD(card_list);
115 
116 static int
packet_buffer_init(struct packet_buffer * buffer,size_t capacity)117 packet_buffer_init(struct packet_buffer *buffer, size_t capacity)
118 {
119 	buffer->data = kmalloc(capacity, GFP_KERNEL);
120 	if (buffer->data == NULL)
121 		return -ENOMEM;
122 	buffer->head = (struct packet *) buffer->data;
123 	buffer->tail = (struct packet *) buffer->data;
124 	buffer->capacity = capacity;
125 	buffer->lost_packet_count = 0;
126 	atomic_set(&buffer->size, 0);
127 	init_waitqueue_head(&buffer->wait);
128 
129 	return 0;
130 }
131 
132 static void
packet_buffer_destroy(struct packet_buffer * buffer)133 packet_buffer_destroy(struct packet_buffer *buffer)
134 {
135 	kfree(buffer->data);
136 }
137 
138 static int
packet_buffer_get(struct client * client,char __user * data,size_t user_length)139 packet_buffer_get(struct client *client, char __user *data, size_t user_length)
140 {
141 	struct packet_buffer *buffer = &client->buffer;
142 	size_t length;
143 	char *end;
144 
145 	if (wait_event_interruptible(buffer->wait,
146 				     atomic_read(&buffer->size) > 0) ||
147 				     list_empty(&client->lynx->link))
148 		return -ERESTARTSYS;
149 
150 	if (atomic_read(&buffer->size) == 0)
151 		return -ENODEV;
152 
153 	length = buffer->head->length;
154 
155 	if (length > user_length)
156 		return 0;
157 
158 	end = buffer->data + buffer->capacity;
159 
160 	if (&buffer->head->data[length] < end) {
161 		if (copy_to_user(data, buffer->head->data, length))
162 			return -EFAULT;
163 		buffer->head = (struct packet *) &buffer->head->data[length];
164 	} else {
165 		size_t split = end - buffer->head->data;
166 
167 		if (copy_to_user(data, buffer->head->data, split))
168 			return -EFAULT;
169 		if (copy_to_user(data + split, buffer->data, length - split))
170 			return -EFAULT;
171 		buffer->head = (struct packet *) &buffer->data[length - split];
172 	}
173 
174 	/*
175 	 * Decrease buffer->size as the last thing, since this is what
176 	 * keeps the interrupt from overwriting the packet we are
177 	 * retrieving from the buffer.
178 	 */
179 	atomic_sub(sizeof(struct packet) + length, &buffer->size);
180 
181 	return length;
182 }
183 
184 static void
packet_buffer_put(struct packet_buffer * buffer,void * data,size_t length)185 packet_buffer_put(struct packet_buffer *buffer, void *data, size_t length)
186 {
187 	char *end;
188 
189 	buffer->total_packet_count++;
190 
191 	if (buffer->capacity <
192 	    atomic_read(&buffer->size) + sizeof(struct packet) + length) {
193 		buffer->lost_packet_count++;
194 		return;
195 	}
196 
197 	end = buffer->data + buffer->capacity;
198 	buffer->tail->length = length;
199 
200 	if (&buffer->tail->data[length] < end) {
201 		memcpy(buffer->tail->data, data, length);
202 		buffer->tail = (struct packet *) &buffer->tail->data[length];
203 	} else {
204 		size_t split = end - buffer->tail->data;
205 
206 		memcpy(buffer->tail->data, data, split);
207 		memcpy(buffer->data, data + split, length - split);
208 		buffer->tail = (struct packet *) &buffer->data[length - split];
209 	}
210 
211 	/* Finally, adjust buffer size and wake up userspace reader. */
212 
213 	atomic_add(sizeof(struct packet) + length, &buffer->size);
214 	wake_up_interruptible(&buffer->wait);
215 }
216 
217 static inline void
reg_write(struct pcilynx * lynx,int offset,u32 data)218 reg_write(struct pcilynx *lynx, int offset, u32 data)
219 {
220 	writel(data, lynx->registers + offset);
221 }
222 
223 static inline u32
reg_read(struct pcilynx * lynx,int offset)224 reg_read(struct pcilynx *lynx, int offset)
225 {
226 	return readl(lynx->registers + offset);
227 }
228 
229 static inline void
reg_set_bits(struct pcilynx * lynx,int offset,u32 mask)230 reg_set_bits(struct pcilynx *lynx, int offset, u32 mask)
231 {
232 	reg_write(lynx, offset, (reg_read(lynx, offset) | mask));
233 }
234 
235 /*
236  * Maybe the pcl programs could be set up to just append data instead
237  * of using a whole packet.
238  */
239 static inline void
run_pcl(struct pcilynx * lynx,dma_addr_t pcl_bus,int dmachan)240 run_pcl(struct pcilynx *lynx, dma_addr_t pcl_bus,
241 			   int dmachan)
242 {
243 	reg_write(lynx, DMA0_CURRENT_PCL + dmachan * 0x20, pcl_bus);
244 	reg_write(lynx, DMA0_CHAN_CTRL + dmachan * 0x20,
245 		  DMA_CHAN_CTRL_ENABLE | DMA_CHAN_CTRL_LINK);
246 }
247 
248 static int
set_phy_reg(struct pcilynx * lynx,int addr,int val)249 set_phy_reg(struct pcilynx *lynx, int addr, int val)
250 {
251 	if (addr > 15) {
252 		dev_err(&lynx->pci_device->dev,
253 			"PHY register address %d out of range\n", addr);
254 		return -1;
255 	}
256 	if (val > 0xff) {
257 		dev_err(&lynx->pci_device->dev,
258 			"PHY register value %d out of range\n", val);
259 		return -1;
260 	}
261 	reg_write(lynx, LINK_PHY, LINK_PHY_WRITE |
262 		  LINK_PHY_ADDR(addr) | LINK_PHY_WDATA(val));
263 
264 	return 0;
265 }
266 
267 static int
nosy_open(struct inode * inode,struct file * file)268 nosy_open(struct inode *inode, struct file *file)
269 {
270 	int minor = iminor(inode);
271 	struct client *client;
272 	struct pcilynx *tmp, *lynx = NULL;
273 
274 	mutex_lock(&card_mutex);
275 	list_for_each_entry(tmp, &card_list, link)
276 		if (tmp->misc.minor == minor) {
277 			lynx = lynx_get(tmp);
278 			break;
279 		}
280 	mutex_unlock(&card_mutex);
281 	if (lynx == NULL)
282 		return -ENODEV;
283 
284 	client = kmalloc(sizeof *client, GFP_KERNEL);
285 	if (client == NULL)
286 		goto fail;
287 
288 	client->tcode_mask = ~0;
289 	client->lynx = lynx;
290 	INIT_LIST_HEAD(&client->link);
291 
292 	if (packet_buffer_init(&client->buffer, 128 * 1024) < 0)
293 		goto fail;
294 
295 	file->private_data = client;
296 
297 	return stream_open(inode, file);
298 fail:
299 	kfree(client);
300 	lynx_put(lynx);
301 
302 	return -ENOMEM;
303 }
304 
305 static int
nosy_release(struct inode * inode,struct file * file)306 nosy_release(struct inode *inode, struct file *file)
307 {
308 	struct client *client = file->private_data;
309 	struct pcilynx *lynx = client->lynx;
310 
311 	spin_lock_irq(&lynx->client_list_lock);
312 	list_del_init(&client->link);
313 	spin_unlock_irq(&lynx->client_list_lock);
314 
315 	packet_buffer_destroy(&client->buffer);
316 	kfree(client);
317 	lynx_put(lynx);
318 
319 	return 0;
320 }
321 
322 static __poll_t
nosy_poll(struct file * file,poll_table * pt)323 nosy_poll(struct file *file, poll_table *pt)
324 {
325 	struct client *client = file->private_data;
326 	__poll_t ret = 0;
327 
328 	poll_wait(file, &client->buffer.wait, pt);
329 
330 	if (atomic_read(&client->buffer.size) > 0)
331 		ret = EPOLLIN | EPOLLRDNORM;
332 
333 	if (list_empty(&client->lynx->link))
334 		ret |= EPOLLHUP;
335 
336 	return ret;
337 }
338 
339 static ssize_t
nosy_read(struct file * file,char __user * buffer,size_t count,loff_t * offset)340 nosy_read(struct file *file, char __user *buffer, size_t count, loff_t *offset)
341 {
342 	struct client *client = file->private_data;
343 
344 	return packet_buffer_get(client, buffer, count);
345 }
346 
347 static long
nosy_ioctl(struct file * file,unsigned int cmd,unsigned long arg)348 nosy_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
349 {
350 	struct client *client = file->private_data;
351 	spinlock_t *client_list_lock = &client->lynx->client_list_lock;
352 	struct nosy_stats stats;
353 	int ret;
354 
355 	switch (cmd) {
356 	case NOSY_IOC_GET_STATS:
357 		spin_lock_irq(client_list_lock);
358 		stats.total_packet_count = client->buffer.total_packet_count;
359 		stats.lost_packet_count  = client->buffer.lost_packet_count;
360 		spin_unlock_irq(client_list_lock);
361 
362 		if (copy_to_user((void __user *) arg, &stats, sizeof stats))
363 			return -EFAULT;
364 		else
365 			return 0;
366 
367 	case NOSY_IOC_START:
368 		ret = -EBUSY;
369 		spin_lock_irq(client_list_lock);
370 		if (list_empty(&client->link)) {
371 			list_add_tail(&client->link, &client->lynx->client_list);
372 			ret = 0;
373 		}
374 		spin_unlock_irq(client_list_lock);
375 
376 		return ret;
377 
378 	case NOSY_IOC_STOP:
379 		spin_lock_irq(client_list_lock);
380 		list_del_init(&client->link);
381 		spin_unlock_irq(client_list_lock);
382 
383 		return 0;
384 
385 	case NOSY_IOC_FILTER:
386 		spin_lock_irq(client_list_lock);
387 		client->tcode_mask = arg;
388 		spin_unlock_irq(client_list_lock);
389 
390 		return 0;
391 
392 	default:
393 		return -EINVAL;
394 		/* Flush buffer, configure filter. */
395 	}
396 }
397 
398 static const struct file_operations nosy_ops = {
399 	.owner =		THIS_MODULE,
400 	.read =			nosy_read,
401 	.unlocked_ioctl =	nosy_ioctl,
402 	.poll =			nosy_poll,
403 	.open =			nosy_open,
404 	.release =		nosy_release,
405 };
406 
407 #define PHY_PACKET_SIZE 12 /* 1 payload, 1 inverse, 1 ack = 3 quadlets */
408 
409 static void
packet_irq_handler(struct pcilynx * lynx)410 packet_irq_handler(struct pcilynx *lynx)
411 {
412 	struct client *client;
413 	u32 tcode_mask, tcode, timestamp;
414 	size_t length;
415 	struct timespec64 ts64;
416 
417 	/* FIXME: Also report rcv_speed. */
418 
419 	length = __le32_to_cpu(lynx->rcv_pcl->pcl_status) & 0x00001fff;
420 	tcode  = __le32_to_cpu(lynx->rcv_buffer[1]) >> 4 & 0xf;
421 
422 	ktime_get_real_ts64(&ts64);
423 	timestamp = ts64.tv_nsec / NSEC_PER_USEC;
424 	lynx->rcv_buffer[0] = (__force __le32)timestamp;
425 
426 	if (length == PHY_PACKET_SIZE)
427 		tcode_mask = 1 << TCODE_PHY_PACKET;
428 	else
429 		tcode_mask = 1 << tcode;
430 
431 	spin_lock(&lynx->client_list_lock);
432 
433 	list_for_each_entry(client, &lynx->client_list, link)
434 		if (client->tcode_mask & tcode_mask)
435 			packet_buffer_put(&client->buffer,
436 					  lynx->rcv_buffer, length + 4);
437 
438 	spin_unlock(&lynx->client_list_lock);
439 }
440 
441 static void
bus_reset_irq_handler(struct pcilynx * lynx)442 bus_reset_irq_handler(struct pcilynx *lynx)
443 {
444 	struct client *client;
445 	struct timespec64 ts64;
446 	u32    timestamp;
447 
448 	ktime_get_real_ts64(&ts64);
449 	timestamp = ts64.tv_nsec / NSEC_PER_USEC;
450 
451 	spin_lock(&lynx->client_list_lock);
452 
453 	list_for_each_entry(client, &lynx->client_list, link)
454 		packet_buffer_put(&client->buffer, &timestamp, 4);
455 
456 	spin_unlock(&lynx->client_list_lock);
457 }
458 
459 static irqreturn_t
irq_handler(int irq,void * device)460 irq_handler(int irq, void *device)
461 {
462 	struct pcilynx *lynx = device;
463 	u32 pci_int_status;
464 
465 	pci_int_status = reg_read(lynx, PCI_INT_STATUS);
466 
467 	if (pci_int_status == ~0)
468 		/* Card was ejected. */
469 		return IRQ_NONE;
470 
471 	if ((pci_int_status & PCI_INT_INT_PEND) == 0)
472 		/* Not our interrupt, bail out quickly. */
473 		return IRQ_NONE;
474 
475 	if ((pci_int_status & PCI_INT_P1394_INT) != 0) {
476 		u32 link_int_status;
477 
478 		link_int_status = reg_read(lynx, LINK_INT_STATUS);
479 		reg_write(lynx, LINK_INT_STATUS, link_int_status);
480 
481 		if ((link_int_status & LINK_INT_PHY_BUSRESET) > 0)
482 			bus_reset_irq_handler(lynx);
483 	}
484 
485 	/* Clear the PCI_INT_STATUS register only after clearing the
486 	 * LINK_INT_STATUS register; otherwise the PCI_INT_P1394 will
487 	 * be set again immediately. */
488 
489 	reg_write(lynx, PCI_INT_STATUS, pci_int_status);
490 
491 	if ((pci_int_status & PCI_INT_DMA0_HLT) > 0) {
492 		packet_irq_handler(lynx);
493 		run_pcl(lynx, lynx->rcv_start_pcl_bus, 0);
494 	}
495 
496 	return IRQ_HANDLED;
497 }
498 
499 static void
remove_card(struct pci_dev * dev)500 remove_card(struct pci_dev *dev)
501 {
502 	struct pcilynx *lynx = pci_get_drvdata(dev);
503 	struct client *client;
504 
505 	mutex_lock(&card_mutex);
506 	list_del_init(&lynx->link);
507 	misc_deregister(&lynx->misc);
508 	mutex_unlock(&card_mutex);
509 
510 	reg_write(lynx, PCI_INT_ENABLE, 0);
511 	free_irq(lynx->pci_device->irq, lynx);
512 
513 	spin_lock_irq(&lynx->client_list_lock);
514 	list_for_each_entry(client, &lynx->client_list, link)
515 		wake_up_interruptible(&client->buffer.wait);
516 	spin_unlock_irq(&lynx->client_list_lock);
517 
518 	dma_free_coherent(&lynx->pci_device->dev, sizeof(struct pcl),
519 			  lynx->rcv_start_pcl, lynx->rcv_start_pcl_bus);
520 	dma_free_coherent(&lynx->pci_device->dev, sizeof(struct pcl),
521 			  lynx->rcv_pcl, lynx->rcv_pcl_bus);
522 	dma_free_coherent(&lynx->pci_device->dev, RCV_BUFFER_SIZE,
523 			  lynx->rcv_buffer, lynx->rcv_buffer_bus);
524 
525 	iounmap(lynx->registers);
526 	pci_disable_device(dev);
527 	lynx_put(lynx);
528 }
529 
530 static int
add_card(struct pci_dev * dev,const struct pci_device_id * unused)531 add_card(struct pci_dev *dev, const struct pci_device_id *unused)
532 {
533 	struct pcilynx *lynx;
534 	u32 p, end;
535 	int ret, i;
536 
537 	if (dma_set_mask(&dev->dev, DMA_BIT_MASK(32))) {
538 		dev_err(&dev->dev,
539 		    "DMA address limits not supported for PCILynx hardware\n");
540 		return -ENXIO;
541 	}
542 	if (pci_enable_device(dev)) {
543 		dev_err(&dev->dev, "Failed to enable PCILynx hardware\n");
544 		return -ENXIO;
545 	}
546 	pci_set_master(dev);
547 
548 	lynx = kzalloc(sizeof *lynx, GFP_KERNEL);
549 	if (lynx == NULL) {
550 		dev_err(&dev->dev, "Failed to allocate control structure\n");
551 		ret = -ENOMEM;
552 		goto fail_disable;
553 	}
554 	lynx->pci_device = dev;
555 	pci_set_drvdata(dev, lynx);
556 
557 	spin_lock_init(&lynx->client_list_lock);
558 	INIT_LIST_HEAD(&lynx->client_list);
559 	kref_init(&lynx->kref);
560 
561 	lynx->registers = ioremap(pci_resource_start(dev, 0),
562 					  PCILYNX_MAX_REGISTER);
563 	if (lynx->registers == NULL) {
564 		dev_err(&dev->dev, "Failed to map registers\n");
565 		ret = -ENOMEM;
566 		goto fail_deallocate_lynx;
567 	}
568 
569 	lynx->rcv_start_pcl = dma_alloc_coherent(&lynx->pci_device->dev,
570 						 sizeof(struct pcl),
571 						 &lynx->rcv_start_pcl_bus,
572 						 GFP_KERNEL);
573 	lynx->rcv_pcl = dma_alloc_coherent(&lynx->pci_device->dev,
574 					   sizeof(struct pcl),
575 					   &lynx->rcv_pcl_bus, GFP_KERNEL);
576 	lynx->rcv_buffer = dma_alloc_coherent(&lynx->pci_device->dev,
577 					      RCV_BUFFER_SIZE,
578 					      &lynx->rcv_buffer_bus, GFP_KERNEL);
579 	if (lynx->rcv_start_pcl == NULL ||
580 	    lynx->rcv_pcl == NULL ||
581 	    lynx->rcv_buffer == NULL) {
582 		dev_err(&dev->dev, "Failed to allocate receive buffer\n");
583 		ret = -ENOMEM;
584 		goto fail_deallocate_buffers;
585 	}
586 	lynx->rcv_start_pcl->next	= cpu_to_le32(lynx->rcv_pcl_bus);
587 	lynx->rcv_pcl->next		= cpu_to_le32(PCL_NEXT_INVALID);
588 	lynx->rcv_pcl->async_error_next	= cpu_to_le32(PCL_NEXT_INVALID);
589 
590 	lynx->rcv_pcl->buffer[0].control =
591 			cpu_to_le32(PCL_CMD_RCV | PCL_BIGENDIAN | 2044);
592 	lynx->rcv_pcl->buffer[0].pointer =
593 			cpu_to_le32(lynx->rcv_buffer_bus + 4);
594 	p = lynx->rcv_buffer_bus + 2048;
595 	end = lynx->rcv_buffer_bus + RCV_BUFFER_SIZE;
596 	for (i = 1; p < end; i++, p += 2048) {
597 		lynx->rcv_pcl->buffer[i].control =
598 			cpu_to_le32(PCL_CMD_RCV | PCL_BIGENDIAN | 2048);
599 		lynx->rcv_pcl->buffer[i].pointer = cpu_to_le32(p);
600 	}
601 	lynx->rcv_pcl->buffer[i - 1].control |= cpu_to_le32(PCL_LAST_BUFF);
602 
603 	reg_set_bits(lynx, MISC_CONTROL, MISC_CONTROL_SWRESET);
604 	/* Fix buggy cards with autoboot pin not tied low: */
605 	reg_write(lynx, DMA0_CHAN_CTRL, 0);
606 	reg_write(lynx, DMA_GLOBAL_REGISTER, 0x00 << 24);
607 
608 #if 0
609 	/* now, looking for PHY register set */
610 	if ((get_phy_reg(lynx, 2) & 0xe0) == 0xe0) {
611 		lynx->phyic.reg_1394a = 1;
612 		PRINT(KERN_INFO, lynx->id,
613 		      "found 1394a conform PHY (using extended register set)");
614 		lynx->phyic.vendor = get_phy_vendorid(lynx);
615 		lynx->phyic.product = get_phy_productid(lynx);
616 	} else {
617 		lynx->phyic.reg_1394a = 0;
618 		PRINT(KERN_INFO, lynx->id, "found old 1394 PHY");
619 	}
620 #endif
621 
622 	/* Setup the general receive FIFO max size. */
623 	reg_write(lynx, FIFO_SIZES, 255);
624 
625 	reg_set_bits(lynx, PCI_INT_ENABLE, PCI_INT_DMA_ALL);
626 
627 	reg_write(lynx, LINK_INT_ENABLE,
628 		  LINK_INT_PHY_TIME_OUT | LINK_INT_PHY_REG_RCVD |
629 		  LINK_INT_PHY_BUSRESET | LINK_INT_IT_STUCK |
630 		  LINK_INT_AT_STUCK | LINK_INT_SNTRJ |
631 		  LINK_INT_TC_ERR | LINK_INT_GRF_OVER_FLOW |
632 		  LINK_INT_ITF_UNDER_FLOW | LINK_INT_ATF_UNDER_FLOW);
633 
634 	/* Disable the L flag in self ID packets. */
635 	set_phy_reg(lynx, 4, 0);
636 
637 	/* Put this baby into snoop mode */
638 	reg_set_bits(lynx, LINK_CONTROL, LINK_CONTROL_SNOOP_ENABLE);
639 
640 	run_pcl(lynx, lynx->rcv_start_pcl_bus, 0);
641 
642 	if (request_irq(dev->irq, irq_handler, IRQF_SHARED,
643 			driver_name, lynx)) {
644 		dev_err(&dev->dev,
645 			"Failed to allocate shared interrupt %d\n", dev->irq);
646 		ret = -EIO;
647 		goto fail_deallocate_buffers;
648 	}
649 
650 	lynx->misc.parent = &dev->dev;
651 	lynx->misc.minor = MISC_DYNAMIC_MINOR;
652 	lynx->misc.name = "nosy";
653 	lynx->misc.fops = &nosy_ops;
654 
655 	mutex_lock(&card_mutex);
656 	ret = misc_register(&lynx->misc);
657 	if (ret) {
658 		dev_err(&dev->dev, "Failed to register misc char device\n");
659 		mutex_unlock(&card_mutex);
660 		goto fail_free_irq;
661 	}
662 	list_add_tail(&lynx->link, &card_list);
663 	mutex_unlock(&card_mutex);
664 
665 	dev_info(&dev->dev,
666 		 "Initialized PCILynx IEEE1394 card, irq=%d\n", dev->irq);
667 
668 	return 0;
669 
670 fail_free_irq:
671 	reg_write(lynx, PCI_INT_ENABLE, 0);
672 	free_irq(lynx->pci_device->irq, lynx);
673 
674 fail_deallocate_buffers:
675 	if (lynx->rcv_start_pcl)
676 		dma_free_coherent(&lynx->pci_device->dev, sizeof(struct pcl),
677 				  lynx->rcv_start_pcl,
678 				  lynx->rcv_start_pcl_bus);
679 	if (lynx->rcv_pcl)
680 		dma_free_coherent(&lynx->pci_device->dev, sizeof(struct pcl),
681 				  lynx->rcv_pcl, lynx->rcv_pcl_bus);
682 	if (lynx->rcv_buffer)
683 		dma_free_coherent(&lynx->pci_device->dev, RCV_BUFFER_SIZE,
684 				  lynx->rcv_buffer, lynx->rcv_buffer_bus);
685 	iounmap(lynx->registers);
686 
687 fail_deallocate_lynx:
688 	kfree(lynx);
689 
690 fail_disable:
691 	pci_disable_device(dev);
692 
693 	return ret;
694 }
695 
696 static struct pci_device_id pci_table[] = {
697 	{
698 		.vendor =    PCI_VENDOR_ID_TI,
699 		.device =    PCI_DEVICE_ID_TI_PCILYNX,
700 		.subvendor = PCI_ANY_ID,
701 		.subdevice = PCI_ANY_ID,
702 	},
703 	{ }	/* Terminating entry */
704 };
705 
706 MODULE_DEVICE_TABLE(pci, pci_table);
707 
708 static struct pci_driver lynx_pci_driver = {
709 	.name =		driver_name,
710 	.id_table =	pci_table,
711 	.probe =	add_card,
712 	.remove =	remove_card,
713 };
714 
715 module_pci_driver(lynx_pci_driver);
716 
717 MODULE_AUTHOR("Kristian Hoegsberg");
718 MODULE_DESCRIPTION("Snoop mode driver for TI pcilynx 1394 controllers");
719 MODULE_LICENSE("GPL");
720