xref: /linux/drivers/firewire/core-device.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Device probing and sysfs code.
4  *
5  * Copyright (C) 2005-2006  Kristian Hoegsberg <krh@bitplanet.net>
6  */
7 
8 #include <linux/bug.h>
9 #include <linux/ctype.h>
10 #include <linux/delay.h>
11 #include <linux/device.h>
12 #include <linux/errno.h>
13 #include <linux/firewire.h>
14 #include <linux/firewire-constants.h>
15 #include <linux/jiffies.h>
16 #include <linux/kobject.h>
17 #include <linux/list.h>
18 #include <linux/mod_devicetable.h>
19 #include <linux/module.h>
20 #include <linux/mutex.h>
21 #include <linux/random.h>
22 #include <linux/rwsem.h>
23 #include <linux/slab.h>
24 #include <linux/spinlock.h>
25 #include <linux/string.h>
26 #include <linux/workqueue.h>
27 
28 #include <linux/atomic.h>
29 #include <asm/byteorder.h>
30 
31 #include "core.h"
32 
33 #define ROOT_DIR_OFFSET	5
34 
35 void fw_csr_iterator_init(struct fw_csr_iterator *ci, const u32 *p)
36 {
37 	ci->p = p + 1;
38 	ci->end = ci->p + (p[0] >> 16);
39 }
40 EXPORT_SYMBOL(fw_csr_iterator_init);
41 
42 int fw_csr_iterator_next(struct fw_csr_iterator *ci, int *key, int *value)
43 {
44 	*key = *ci->p >> 24;
45 	*value = *ci->p & 0xffffff;
46 
47 	return ci->p++ < ci->end;
48 }
49 EXPORT_SYMBOL(fw_csr_iterator_next);
50 
51 static const u32 *search_directory(const u32 *directory, int search_key)
52 {
53 	struct fw_csr_iterator ci;
54 	int key, value;
55 
56 	search_key |= CSR_DIRECTORY;
57 
58 	fw_csr_iterator_init(&ci, directory);
59 	while (fw_csr_iterator_next(&ci, &key, &value)) {
60 		if (key == search_key)
61 			return ci.p - 1 + value;
62 	}
63 
64 	return NULL;
65 }
66 
67 static const u32 *search_leaf(const u32 *directory, int search_key)
68 {
69 	struct fw_csr_iterator ci;
70 	int last_key = 0, key, value;
71 
72 	fw_csr_iterator_init(&ci, directory);
73 	while (fw_csr_iterator_next(&ci, &key, &value)) {
74 		if (last_key == search_key &&
75 		    key == (CSR_DESCRIPTOR | CSR_LEAF))
76 			return ci.p - 1 + value;
77 
78 		last_key = key;
79 	}
80 
81 	return NULL;
82 }
83 
84 static int textual_leaf_to_string(const u32 *block, char *buf, size_t size)
85 {
86 	unsigned int quadlets, i;
87 	char c;
88 
89 	if (!size || !buf)
90 		return -EINVAL;
91 
92 	quadlets = min(block[0] >> 16, 256U);
93 	if (quadlets < 2)
94 		return -ENODATA;
95 
96 	if (block[1] != 0 || block[2] != 0)
97 		/* unknown language/character set */
98 		return -ENODATA;
99 
100 	block += 3;
101 	quadlets -= 2;
102 	for (i = 0; i < quadlets * 4 && i < size - 1; i++) {
103 		c = block[i / 4] >> (24 - 8 * (i % 4));
104 		if (c == '\0')
105 			break;
106 		buf[i] = c;
107 	}
108 	buf[i] = '\0';
109 
110 	return i;
111 }
112 
113 /**
114  * fw_csr_string() - reads a string from the configuration ROM
115  * @directory:	e.g. root directory or unit directory
116  * @key:	the key of the preceding directory entry
117  * @buf:	where to put the string
118  * @size:	size of @buf, in bytes
119  *
120  * The string is taken from a minimal ASCII text descriptor leaf just after the entry with the
121  * @key. The string is zero-terminated. An overlong string is silently truncated such that it
122  * and the zero byte fit into @size.
123  *
124  * Returns strlen(buf) or a negative error code.
125  */
126 int fw_csr_string(const u32 *directory, int key, char *buf, size_t size)
127 {
128 	const u32 *leaf = search_leaf(directory, key);
129 	if (!leaf)
130 		return -ENOENT;
131 
132 	return textual_leaf_to_string(leaf, buf, size);
133 }
134 EXPORT_SYMBOL(fw_csr_string);
135 
136 static void get_ids(const u32 *directory, int *id)
137 {
138 	struct fw_csr_iterator ci;
139 	int key, value;
140 
141 	fw_csr_iterator_init(&ci, directory);
142 	while (fw_csr_iterator_next(&ci, &key, &value)) {
143 		switch (key) {
144 		case CSR_VENDOR:	id[0] = value; break;
145 		case CSR_MODEL:		id[1] = value; break;
146 		case CSR_SPECIFIER_ID:	id[2] = value; break;
147 		case CSR_VERSION:	id[3] = value; break;
148 		}
149 	}
150 }
151 
152 static void get_modalias_ids(const struct fw_unit *unit, int *id)
153 {
154 	const u32 *root_directory = &fw_parent_device(unit)->config_rom[ROOT_DIR_OFFSET];
155 	const u32 *directories[] = {NULL, NULL, NULL};
156 	const u32 *vendor_directory;
157 	int i;
158 
159 	directories[0] = root_directory;
160 
161 	// Legacy layout of configuration ROM described in Annex 1 of 'Configuration ROM for AV/C
162 	// Devices 1.0 (December 12, 2000, 1394 Trading Association, TA Document 1999027)'.
163 	vendor_directory = search_directory(root_directory, CSR_VENDOR);
164 	if (!vendor_directory) {
165 		directories[1] = unit->directory;
166 	} else {
167 		directories[1] = vendor_directory;
168 		directories[2] = unit->directory;
169 	}
170 
171 	for (i = 0; i < ARRAY_SIZE(directories) && !!directories[i]; ++i)
172 		get_ids(directories[i], id);
173 }
174 
175 static bool match_ids(const struct ieee1394_device_id *id_table, int *id)
176 {
177 	int match = 0;
178 
179 	if (id[0] == id_table->vendor_id)
180 		match |= IEEE1394_MATCH_VENDOR_ID;
181 	if (id[1] == id_table->model_id)
182 		match |= IEEE1394_MATCH_MODEL_ID;
183 	if (id[2] == id_table->specifier_id)
184 		match |= IEEE1394_MATCH_SPECIFIER_ID;
185 	if (id[3] == id_table->version)
186 		match |= IEEE1394_MATCH_VERSION;
187 
188 	return (match & id_table->match_flags) == id_table->match_flags;
189 }
190 
191 static const struct ieee1394_device_id *unit_match(struct device *dev,
192 						   const struct device_driver *drv)
193 {
194 	const struct ieee1394_device_id *id_table =
195 			container_of_const(drv, struct fw_driver, driver)->id_table;
196 	int id[] = {0, 0, 0, 0};
197 
198 	get_modalias_ids(fw_unit(dev), id);
199 
200 	for (; id_table->match_flags != 0; id_table++)
201 		if (match_ids(id_table, id))
202 			return id_table;
203 
204 	return NULL;
205 }
206 
207 static bool is_fw_unit(const struct device *dev);
208 
209 static int fw_unit_match(struct device *dev, const struct device_driver *drv)
210 {
211 	/* We only allow binding to fw_units. */
212 	return is_fw_unit(dev) && unit_match(dev, drv) != NULL;
213 }
214 
215 static int fw_unit_probe(struct device *dev)
216 {
217 	struct fw_driver *driver =
218 			container_of(dev->driver, struct fw_driver, driver);
219 
220 	return driver->probe(fw_unit(dev), unit_match(dev, dev->driver));
221 }
222 
223 static void fw_unit_remove(struct device *dev)
224 {
225 	struct fw_driver *driver =
226 			container_of(dev->driver, struct fw_driver, driver);
227 
228 	driver->remove(fw_unit(dev));
229 }
230 
231 static int get_modalias(const struct fw_unit *unit, char *buffer, size_t buffer_size)
232 {
233 	int id[] = {0, 0, 0, 0};
234 
235 	get_modalias_ids(unit, id);
236 
237 	return snprintf(buffer, buffer_size,
238 			"ieee1394:ven%08Xmo%08Xsp%08Xver%08X",
239 			id[0], id[1], id[2], id[3]);
240 }
241 
242 static int fw_unit_uevent(const struct device *dev, struct kobj_uevent_env *env)
243 {
244 	const struct fw_unit *unit = fw_unit(dev);
245 	char modalias[64];
246 
247 	get_modalias(unit, modalias, sizeof(modalias));
248 
249 	if (add_uevent_var(env, "MODALIAS=%s", modalias))
250 		return -ENOMEM;
251 
252 	return 0;
253 }
254 
255 const struct bus_type fw_bus_type = {
256 	.name = "firewire",
257 	.match = fw_unit_match,
258 	.probe = fw_unit_probe,
259 	.remove = fw_unit_remove,
260 };
261 EXPORT_SYMBOL(fw_bus_type);
262 
263 int fw_device_enable_phys_dma(struct fw_device *device)
264 {
265 	int generation = device->generation;
266 
267 	/* device->node_id, accessed below, must not be older than generation */
268 	smp_rmb();
269 
270 	return device->card->driver->enable_phys_dma(device->card,
271 						     device->node_id,
272 						     generation);
273 }
274 EXPORT_SYMBOL(fw_device_enable_phys_dma);
275 
276 struct config_rom_attribute {
277 	struct device_attribute attr;
278 	u32 key;
279 };
280 
281 static ssize_t show_immediate(struct device *dev,
282 			      struct device_attribute *dattr, char *buf)
283 {
284 	struct config_rom_attribute *attr =
285 		container_of(dattr, struct config_rom_attribute, attr);
286 	struct fw_csr_iterator ci;
287 	const u32 *directories[] = {NULL, NULL};
288 	int i, value = -1;
289 
290 	guard(rwsem_read)(&fw_device_rwsem);
291 
292 	if (is_fw_unit(dev)) {
293 		directories[0] = fw_unit(dev)->directory;
294 	} else {
295 		const u32 *root_directory = fw_device(dev)->config_rom + ROOT_DIR_OFFSET;
296 		const u32 *vendor_directory = search_directory(root_directory, CSR_VENDOR);
297 
298 		if (!vendor_directory) {
299 			directories[0] = root_directory;
300 		} else {
301 			// Legacy layout of configuration ROM described in Annex 1 of
302 			// 'Configuration ROM for AV/C Devices 1.0 (December 12, 2000, 1394 Trading
303 			// Association, TA Document 1999027)'.
304 			directories[0] = vendor_directory;
305 			directories[1] = root_directory;
306 		}
307 	}
308 
309 	for (i = 0; i < ARRAY_SIZE(directories) && !!directories[i]; ++i) {
310 		int key, val;
311 
312 		fw_csr_iterator_init(&ci, directories[i]);
313 		while (fw_csr_iterator_next(&ci, &key, &val)) {
314 			if (attr->key == key)
315 				value = val;
316 		}
317 	}
318 
319 	if (value < 0)
320 		return -ENOENT;
321 
322 	// Note that this function is also called by init_fw_attribute_group() with NULL pointer.
323 	return buf ? sysfs_emit(buf, "0x%06x\n", value) : 0;
324 }
325 
326 #define IMMEDIATE_ATTR(name, key)				\
327 	{ __ATTR(name, S_IRUGO, show_immediate, NULL), key }
328 
329 static ssize_t show_text_leaf(struct device *dev,
330 			      struct device_attribute *dattr, char *buf)
331 {
332 	struct config_rom_attribute *attr =
333 		container_of(dattr, struct config_rom_attribute, attr);
334 	const u32 *directories[] = {NULL, NULL};
335 	size_t bufsize;
336 	char dummy_buf[2];
337 	int i, ret = -ENOENT;
338 
339 	guard(rwsem_read)(&fw_device_rwsem);
340 
341 	if (is_fw_unit(dev)) {
342 		directories[0] = fw_unit(dev)->directory;
343 	} else {
344 		const u32 *root_directory = fw_device(dev)->config_rom + ROOT_DIR_OFFSET;
345 		const u32 *vendor_directory = search_directory(root_directory, CSR_VENDOR);
346 
347 		if (!vendor_directory) {
348 			directories[0] = root_directory;
349 		} else {
350 			// Legacy layout of configuration ROM described in Annex 1 of
351 			// 'Configuration ROM for AV/C Devices 1.0 (December 12, 2000, 1394
352 			// Trading Association, TA Document 1999027)'.
353 			directories[0] = root_directory;
354 			directories[1] = vendor_directory;
355 		}
356 	}
357 
358 	// Note that this function is also called by init_fw_attribute_group() with NULL pointer.
359 	if (buf) {
360 		bufsize = PAGE_SIZE - 1;
361 	} else {
362 		buf = dummy_buf;
363 		bufsize = 1;
364 	}
365 
366 	for (i = 0; i < ARRAY_SIZE(directories) && !!directories[i]; ++i) {
367 		int result = fw_csr_string(directories[i], attr->key, buf, bufsize);
368 		// Detected.
369 		if (result >= 0) {
370 			ret = result;
371 		} else if (i == 0 && attr->key == CSR_VENDOR) {
372 			// Sony DVMC-DA1 has configuration ROM such that the descriptor leaf entry
373 			// in the root directory follows to the directory entry for vendor ID
374 			// instead of the immediate value for vendor ID.
375 			result = fw_csr_string(directories[i], CSR_DIRECTORY | attr->key, buf,
376 					       bufsize);
377 			if (result >= 0)
378 				ret = result;
379 		}
380 	}
381 
382 	if (ret < 0)
383 		return ret;
384 
385 	// Strip trailing whitespace and add newline.
386 	while (ret > 0 && isspace(buf[ret - 1]))
387 		ret--;
388 	strcpy(buf + ret, "\n");
389 	ret++;
390 
391 	return ret;
392 }
393 
394 #define TEXT_LEAF_ATTR(name, key)				\
395 	{ __ATTR(name, S_IRUGO, show_text_leaf, NULL), key }
396 
397 static struct config_rom_attribute config_rom_attributes[] = {
398 	IMMEDIATE_ATTR(vendor, CSR_VENDOR),
399 	IMMEDIATE_ATTR(hardware_version, CSR_HARDWARE_VERSION),
400 	IMMEDIATE_ATTR(specifier_id, CSR_SPECIFIER_ID),
401 	IMMEDIATE_ATTR(version, CSR_VERSION),
402 	IMMEDIATE_ATTR(model, CSR_MODEL),
403 	TEXT_LEAF_ATTR(vendor_name, CSR_VENDOR),
404 	TEXT_LEAF_ATTR(model_name, CSR_MODEL),
405 	TEXT_LEAF_ATTR(hardware_version_name, CSR_HARDWARE_VERSION),
406 };
407 
408 static void init_fw_attribute_group(struct device *dev,
409 				    struct device_attribute *attrs,
410 				    struct fw_attribute_group *group)
411 {
412 	struct device_attribute *attr;
413 	int i, j;
414 
415 	for (j = 0; attrs[j].attr.name != NULL; j++)
416 		group->attrs[j] = &attrs[j].attr;
417 
418 	for (i = 0; i < ARRAY_SIZE(config_rom_attributes); i++) {
419 		attr = &config_rom_attributes[i].attr;
420 		if (attr->show(dev, attr, NULL) < 0)
421 			continue;
422 		group->attrs[j++] = &attr->attr;
423 	}
424 
425 	group->attrs[j] = NULL;
426 	group->groups[0] = &group->group;
427 	group->groups[1] = NULL;
428 	group->group.attrs = group->attrs;
429 	dev->groups = (const struct attribute_group **) group->groups;
430 }
431 
432 static ssize_t modalias_show(struct device *dev,
433 			     struct device_attribute *attr, char *buf)
434 {
435 	struct fw_unit *unit = fw_unit(dev);
436 	int length;
437 
438 	length = get_modalias(unit, buf, PAGE_SIZE);
439 	strcpy(buf + length, "\n");
440 
441 	return length + 1;
442 }
443 
444 static ssize_t rom_index_show(struct device *dev,
445 			      struct device_attribute *attr, char *buf)
446 {
447 	struct fw_device *device = fw_device(dev->parent);
448 	struct fw_unit *unit = fw_unit(dev);
449 
450 	return sysfs_emit(buf, "%td\n", unit->directory - device->config_rom);
451 }
452 
453 static struct device_attribute fw_unit_attributes[] = {
454 	__ATTR_RO(modalias),
455 	__ATTR_RO(rom_index),
456 	__ATTR_NULL,
457 };
458 
459 static ssize_t config_rom_show(struct device *dev,
460 			       struct device_attribute *attr, char *buf)
461 {
462 	struct fw_device *device = fw_device(dev);
463 	size_t length;
464 
465 	guard(rwsem_read)(&fw_device_rwsem);
466 
467 	length = device->config_rom_length * 4;
468 	memcpy(buf, device->config_rom, length);
469 
470 	return length;
471 }
472 
473 static ssize_t guid_show(struct device *dev,
474 			 struct device_attribute *attr, char *buf)
475 {
476 	struct fw_device *device = fw_device(dev);
477 
478 	guard(rwsem_read)(&fw_device_rwsem);
479 
480 	return sysfs_emit(buf, "0x%08x%08x\n", device->config_rom[3], device->config_rom[4]);
481 }
482 
483 static ssize_t is_local_show(struct device *dev,
484 			     struct device_attribute *attr, char *buf)
485 {
486 	struct fw_device *device = fw_device(dev);
487 
488 	return sysfs_emit(buf, "%u\n", device->is_local);
489 }
490 
491 static int units_sprintf(char *buf, const u32 *directory)
492 {
493 	struct fw_csr_iterator ci;
494 	int key, value;
495 	int specifier_id = 0;
496 	int version = 0;
497 
498 	fw_csr_iterator_init(&ci, directory);
499 	while (fw_csr_iterator_next(&ci, &key, &value)) {
500 		switch (key) {
501 		case CSR_SPECIFIER_ID:
502 			specifier_id = value;
503 			break;
504 		case CSR_VERSION:
505 			version = value;
506 			break;
507 		}
508 	}
509 
510 	return sprintf(buf, "0x%06x:0x%06x ", specifier_id, version);
511 }
512 
513 static ssize_t units_show(struct device *dev,
514 			  struct device_attribute *attr, char *buf)
515 {
516 	struct fw_device *device = fw_device(dev);
517 	struct fw_csr_iterator ci;
518 	int key, value, i = 0;
519 
520 	guard(rwsem_read)(&fw_device_rwsem);
521 
522 	fw_csr_iterator_init(&ci, &device->config_rom[ROOT_DIR_OFFSET]);
523 	while (fw_csr_iterator_next(&ci, &key, &value)) {
524 		if (key != (CSR_UNIT | CSR_DIRECTORY))
525 			continue;
526 		i += units_sprintf(&buf[i], ci.p + value - 1);
527 		if (i >= PAGE_SIZE - (8 + 1 + 8 + 1))
528 			break;
529 	}
530 
531 	if (i)
532 		buf[i - 1] = '\n';
533 
534 	return i;
535 }
536 
537 static struct device_attribute fw_device_attributes[] = {
538 	__ATTR_RO(config_rom),
539 	__ATTR_RO(guid),
540 	__ATTR_RO(is_local),
541 	__ATTR_RO(units),
542 	__ATTR_NULL,
543 };
544 
545 static int read_rom(struct fw_device *device,
546 		    int generation, int index, u32 *data)
547 {
548 	u64 offset = (CSR_REGISTER_BASE | CSR_CONFIG_ROM) + index * 4;
549 	int i, rcode;
550 
551 	/* device->node_id, accessed below, must not be older than generation */
552 	smp_rmb();
553 
554 	for (i = 10; i < 100; i += 10) {
555 		rcode = fw_run_transaction(device->card,
556 				TCODE_READ_QUADLET_REQUEST, device->node_id,
557 				generation, device->max_speed, offset, data, 4);
558 		if (rcode != RCODE_BUSY)
559 			break;
560 		msleep(i);
561 	}
562 	be32_to_cpus(data);
563 
564 	return rcode;
565 }
566 
567 // By quadlet unit.
568 #define MAX_CONFIG_ROM_SIZE	((CSR_CONFIG_ROM_END - CSR_CONFIG_ROM) / sizeof(u32))
569 
570 /*
571  * Read the bus info block, perform a speed probe, and read all of the rest of
572  * the config ROM.  We do all this with a cached bus generation.  If the bus
573  * generation changes under us, read_config_rom will fail and get retried.
574  * It's better to start all over in this case because the node from which we
575  * are reading the ROM may have changed the ROM during the reset.
576  * Returns either a result code or a negative error code.
577  */
578 static int read_config_rom(struct fw_device *device, int generation)
579 {
580 	struct fw_card *card = device->card;
581 	const u32 *old_rom, *new_rom;
582 	u32 *rom, *stack;
583 	u32 sp, key;
584 	int i, end, length, ret;
585 
586 	rom = kmalloc(sizeof(*rom) * MAX_CONFIG_ROM_SIZE +
587 		      sizeof(*stack) * MAX_CONFIG_ROM_SIZE, GFP_KERNEL);
588 	if (rom == NULL)
589 		return -ENOMEM;
590 
591 	stack = &rom[MAX_CONFIG_ROM_SIZE];
592 	memset(rom, 0, sizeof(*rom) * MAX_CONFIG_ROM_SIZE);
593 
594 	device->max_speed = SCODE_100;
595 
596 	/* First read the bus info block. */
597 	for (i = 0; i < 5; i++) {
598 		ret = read_rom(device, generation, i, &rom[i]);
599 		if (ret != RCODE_COMPLETE)
600 			goto out;
601 		/*
602 		 * As per IEEE1212 7.2, during initialization, devices can
603 		 * reply with a 0 for the first quadlet of the config
604 		 * rom to indicate that they are booting (for example,
605 		 * if the firmware is on the disk of a external
606 		 * harddisk).  In that case we just fail, and the
607 		 * retry mechanism will try again later.
608 		 */
609 		if (i == 0 && rom[i] == 0) {
610 			ret = RCODE_BUSY;
611 			goto out;
612 		}
613 	}
614 
615 	device->max_speed = device->node->max_speed;
616 
617 	/*
618 	 * Determine the speed of
619 	 *   - devices with link speed less than PHY speed,
620 	 *   - devices with 1394b PHY (unless only connected to 1394a PHYs),
621 	 *   - all devices if there are 1394b repeaters.
622 	 * Note, we cannot use the bus info block's link_spd as starting point
623 	 * because some buggy firmwares set it lower than necessary and because
624 	 * 1394-1995 nodes do not have the field.
625 	 */
626 	if ((rom[2] & 0x7) < device->max_speed ||
627 	    device->max_speed == SCODE_BETA ||
628 	    card->beta_repeaters_present) {
629 		u32 dummy;
630 
631 		/* for S1600 and S3200 */
632 		if (device->max_speed == SCODE_BETA)
633 			device->max_speed = card->link_speed;
634 
635 		while (device->max_speed > SCODE_100) {
636 			if (read_rom(device, generation, 0, &dummy) ==
637 			    RCODE_COMPLETE)
638 				break;
639 			device->max_speed--;
640 		}
641 	}
642 
643 	/*
644 	 * Now parse the config rom.  The config rom is a recursive
645 	 * directory structure so we parse it using a stack of
646 	 * references to the blocks that make up the structure.  We
647 	 * push a reference to the root directory on the stack to
648 	 * start things off.
649 	 */
650 	length = i;
651 	sp = 0;
652 	stack[sp++] = 0xc0000005;
653 	while (sp > 0) {
654 		/*
655 		 * Pop the next block reference of the stack.  The
656 		 * lower 24 bits is the offset into the config rom,
657 		 * the upper 8 bits are the type of the reference the
658 		 * block.
659 		 */
660 		key = stack[--sp];
661 		i = key & 0xffffff;
662 		if (WARN_ON(i >= MAX_CONFIG_ROM_SIZE)) {
663 			ret = -ENXIO;
664 			goto out;
665 		}
666 
667 		/* Read header quadlet for the block to get the length. */
668 		ret = read_rom(device, generation, i, &rom[i]);
669 		if (ret != RCODE_COMPLETE)
670 			goto out;
671 		end = i + (rom[i] >> 16) + 1;
672 		if (end > MAX_CONFIG_ROM_SIZE) {
673 			/*
674 			 * This block extends outside the config ROM which is
675 			 * a firmware bug.  Ignore this whole block, i.e.
676 			 * simply set a fake block length of 0.
677 			 */
678 			fw_err(card, "skipped invalid ROM block %x at %llx\n",
679 			       rom[i],
680 			       i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
681 			rom[i] = 0;
682 			end = i;
683 		}
684 		i++;
685 
686 		/*
687 		 * Now read in the block.  If this is a directory
688 		 * block, check the entries as we read them to see if
689 		 * it references another block, and push it in that case.
690 		 */
691 		for (; i < end; i++) {
692 			ret = read_rom(device, generation, i, &rom[i]);
693 			if (ret != RCODE_COMPLETE)
694 				goto out;
695 
696 			if ((key >> 30) != 3 || (rom[i] >> 30) < 2)
697 				continue;
698 			/*
699 			 * Offset points outside the ROM.  May be a firmware
700 			 * bug or an Extended ROM entry (IEEE 1212-2001 clause
701 			 * 7.7.18).  Simply overwrite this pointer here by a
702 			 * fake immediate entry so that later iterators over
703 			 * the ROM don't have to check offsets all the time.
704 			 */
705 			if (i + (rom[i] & 0xffffff) >= MAX_CONFIG_ROM_SIZE) {
706 				fw_err(card,
707 				       "skipped unsupported ROM entry %x at %llx\n",
708 				       rom[i],
709 				       i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
710 				rom[i] = 0;
711 				continue;
712 			}
713 			stack[sp++] = i + rom[i];
714 		}
715 		if (length < i)
716 			length = i;
717 	}
718 
719 	old_rom = device->config_rom;
720 	new_rom = kmemdup(rom, length * 4, GFP_KERNEL);
721 	if (new_rom == NULL) {
722 		ret = -ENOMEM;
723 		goto out;
724 	}
725 
726 	scoped_guard(rwsem_write, &fw_device_rwsem) {
727 		device->config_rom = new_rom;
728 		device->config_rom_length = length;
729 	}
730 
731 	kfree(old_rom);
732 	ret = RCODE_COMPLETE;
733 	device->max_rec	= rom[2] >> 12 & 0xf;
734 	device->cmc	= rom[2] >> 30 & 1;
735 	device->irmc	= rom[2] >> 31 & 1;
736  out:
737 	kfree(rom);
738 
739 	return ret;
740 }
741 
742 static void fw_unit_release(struct device *dev)
743 {
744 	struct fw_unit *unit = fw_unit(dev);
745 
746 	fw_device_put(fw_parent_device(unit));
747 	kfree(unit);
748 }
749 
750 static struct device_type fw_unit_type = {
751 	.uevent		= fw_unit_uevent,
752 	.release	= fw_unit_release,
753 };
754 
755 static bool is_fw_unit(const struct device *dev)
756 {
757 	return dev->type == &fw_unit_type;
758 }
759 
760 static void create_units(struct fw_device *device)
761 {
762 	struct fw_csr_iterator ci;
763 	struct fw_unit *unit;
764 	int key, value, i;
765 
766 	i = 0;
767 	fw_csr_iterator_init(&ci, &device->config_rom[ROOT_DIR_OFFSET]);
768 	while (fw_csr_iterator_next(&ci, &key, &value)) {
769 		if (key != (CSR_UNIT | CSR_DIRECTORY))
770 			continue;
771 
772 		/*
773 		 * Get the address of the unit directory and try to
774 		 * match the drivers id_tables against it.
775 		 */
776 		unit = kzalloc(sizeof(*unit), GFP_KERNEL);
777 		if (unit == NULL)
778 			continue;
779 
780 		unit->directory = ci.p + value - 1;
781 		unit->device.bus = &fw_bus_type;
782 		unit->device.type = &fw_unit_type;
783 		unit->device.parent = &device->device;
784 		dev_set_name(&unit->device, "%s.%d", dev_name(&device->device), i++);
785 
786 		BUILD_BUG_ON(ARRAY_SIZE(unit->attribute_group.attrs) <
787 				ARRAY_SIZE(fw_unit_attributes) +
788 				ARRAY_SIZE(config_rom_attributes));
789 		init_fw_attribute_group(&unit->device,
790 					fw_unit_attributes,
791 					&unit->attribute_group);
792 
793 		fw_device_get(device);
794 		if (device_register(&unit->device) < 0) {
795 			put_device(&unit->device);
796 			continue;
797 		}
798 	}
799 }
800 
801 static int shutdown_unit(struct device *device, void *data)
802 {
803 	device_unregister(device);
804 
805 	return 0;
806 }
807 
808 /*
809  * fw_device_rwsem acts as dual purpose mutex:
810  *   - serializes accesses to fw_device.config_rom/.config_rom_length and
811  *     fw_unit.directory, unless those accesses happen at safe occasions
812  */
813 DECLARE_RWSEM(fw_device_rwsem);
814 
815 DEFINE_XARRAY_ALLOC(fw_device_xa);
816 int fw_cdev_major;
817 
818 struct fw_device *fw_device_get_by_devt(dev_t devt)
819 {
820 	struct fw_device *device;
821 
822 	device = xa_load(&fw_device_xa, MINOR(devt));
823 	if (device)
824 		fw_device_get(device);
825 
826 	return device;
827 }
828 
829 struct workqueue_struct *fw_workqueue;
830 EXPORT_SYMBOL(fw_workqueue);
831 
832 static void fw_schedule_device_work(struct fw_device *device,
833 				    unsigned long delay)
834 {
835 	queue_delayed_work(fw_workqueue, &device->work, delay);
836 }
837 
838 /*
839  * These defines control the retry behavior for reading the config
840  * rom.  It shouldn't be necessary to tweak these; if the device
841  * doesn't respond to a config rom read within 10 seconds, it's not
842  * going to respond at all.  As for the initial delay, a lot of
843  * devices will be able to respond within half a second after bus
844  * reset.  On the other hand, it's not really worth being more
845  * aggressive than that, since it scales pretty well; if 10 devices
846  * are plugged in, they're all getting read within one second.
847  */
848 
849 #define MAX_RETRIES	10
850 #define RETRY_DELAY	(3 * HZ)
851 #define INITIAL_DELAY	(HZ / 2)
852 #define SHUTDOWN_DELAY	(2 * HZ)
853 
854 static void fw_device_shutdown(struct work_struct *work)
855 {
856 	struct fw_device *device =
857 		container_of(work, struct fw_device, work.work);
858 
859 	if (time_before64(get_jiffies_64(),
860 			  device->card->reset_jiffies + SHUTDOWN_DELAY)
861 	    && !list_empty(&device->card->link)) {
862 		fw_schedule_device_work(device, SHUTDOWN_DELAY);
863 		return;
864 	}
865 
866 	if (atomic_cmpxchg(&device->state,
867 			   FW_DEVICE_GONE,
868 			   FW_DEVICE_SHUTDOWN) != FW_DEVICE_GONE)
869 		return;
870 
871 	fw_device_cdev_remove(device);
872 	device_for_each_child(&device->device, NULL, shutdown_unit);
873 	device_unregister(&device->device);
874 
875 	xa_erase(&fw_device_xa, MINOR(device->device.devt));
876 
877 	fw_device_put(device);
878 }
879 
880 static void fw_device_release(struct device *dev)
881 {
882 	struct fw_device *device = fw_device(dev);
883 	struct fw_card *card = device->card;
884 
885 	/*
886 	 * Take the card lock so we don't set this to NULL while a
887 	 * FW_NODE_UPDATED callback is being handled or while the
888 	 * bus manager work looks at this node.
889 	 */
890 	scoped_guard(spinlock_irqsave, &card->lock)
891 		device->node->data = NULL;
892 
893 	fw_node_put(device->node);
894 	kfree(device->config_rom);
895 	kfree(device);
896 	fw_card_put(card);
897 }
898 
899 static struct device_type fw_device_type = {
900 	.release = fw_device_release,
901 };
902 
903 static bool is_fw_device(const struct device *dev)
904 {
905 	return dev->type == &fw_device_type;
906 }
907 
908 static int update_unit(struct device *dev, void *data)
909 {
910 	struct fw_unit *unit = fw_unit(dev);
911 	struct fw_driver *driver = (struct fw_driver *)dev->driver;
912 
913 	if (is_fw_unit(dev) && driver != NULL && driver->update != NULL) {
914 		device_lock(dev);
915 		driver->update(unit);
916 		device_unlock(dev);
917 	}
918 
919 	return 0;
920 }
921 
922 static void fw_device_update(struct work_struct *work)
923 {
924 	struct fw_device *device =
925 		container_of(work, struct fw_device, work.work);
926 
927 	fw_device_cdev_update(device);
928 	device_for_each_child(&device->device, NULL, update_unit);
929 }
930 
931 enum { BC_UNKNOWN = 0, BC_UNIMPLEMENTED, BC_IMPLEMENTED, };
932 
933 static void set_broadcast_channel(struct fw_device *device, int generation)
934 {
935 	struct fw_card *card = device->card;
936 	__be32 data;
937 	int rcode;
938 
939 	if (!card->broadcast_channel_allocated)
940 		return;
941 
942 	/*
943 	 * The Broadcast_Channel Valid bit is required by nodes which want to
944 	 * transmit on this channel.  Such transmissions are practically
945 	 * exclusive to IP over 1394 (RFC 2734).  IP capable nodes are required
946 	 * to be IRM capable and have a max_rec of 8 or more.  We use this fact
947 	 * to narrow down to which nodes we send Broadcast_Channel updates.
948 	 */
949 	if (!device->irmc || device->max_rec < 8)
950 		return;
951 
952 	/*
953 	 * Some 1394-1995 nodes crash if this 1394a-2000 register is written.
954 	 * Perform a read test first.
955 	 */
956 	if (device->bc_implemented == BC_UNKNOWN) {
957 		rcode = fw_run_transaction(card, TCODE_READ_QUADLET_REQUEST,
958 				device->node_id, generation, device->max_speed,
959 				CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
960 				&data, 4);
961 		switch (rcode) {
962 		case RCODE_COMPLETE:
963 			if (data & cpu_to_be32(1 << 31)) {
964 				device->bc_implemented = BC_IMPLEMENTED;
965 				break;
966 			}
967 			fallthrough;	/* to case address error */
968 		case RCODE_ADDRESS_ERROR:
969 			device->bc_implemented = BC_UNIMPLEMENTED;
970 		}
971 	}
972 
973 	if (device->bc_implemented == BC_IMPLEMENTED) {
974 		data = cpu_to_be32(BROADCAST_CHANNEL_INITIAL |
975 				   BROADCAST_CHANNEL_VALID);
976 		fw_run_transaction(card, TCODE_WRITE_QUADLET_REQUEST,
977 				device->node_id, generation, device->max_speed,
978 				CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
979 				&data, 4);
980 	}
981 }
982 
983 int fw_device_set_broadcast_channel(struct device *dev, void *gen)
984 {
985 	if (is_fw_device(dev))
986 		set_broadcast_channel(fw_device(dev), (long)gen);
987 
988 	return 0;
989 }
990 
991 static int compare_configuration_rom(struct device *dev, void *data)
992 {
993 	const struct fw_device *old = fw_device(dev);
994 	const u32 *config_rom = data;
995 
996 	if (!is_fw_device(dev))
997 		return 0;
998 
999 	// Compare the bus information block and root_length/root_crc.
1000 	return !memcmp(old->config_rom, config_rom, 6 * 4);
1001 }
1002 
1003 static void fw_device_init(struct work_struct *work)
1004 {
1005 	struct fw_device *device =
1006 		container_of(work, struct fw_device, work.work);
1007 	struct fw_card *card = device->card;
1008 	struct device *found;
1009 	u32 minor;
1010 	int ret;
1011 
1012 	/*
1013 	 * All failure paths here set node->data to NULL, so that we
1014 	 * don't try to do device_for_each_child() on a kfree()'d
1015 	 * device.
1016 	 */
1017 
1018 	ret = read_config_rom(device, device->generation);
1019 	if (ret != RCODE_COMPLETE) {
1020 		if (device->config_rom_retries < MAX_RETRIES &&
1021 		    atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
1022 			device->config_rom_retries++;
1023 			fw_schedule_device_work(device, RETRY_DELAY);
1024 		} else {
1025 			if (device->node->link_on)
1026 				fw_notice(card, "giving up on node %x: reading config rom failed: %s\n",
1027 					  device->node_id,
1028 					  fw_rcode_string(ret));
1029 			if (device->node == card->root_node)
1030 				fw_schedule_bm_work(card, 0);
1031 			fw_device_release(&device->device);
1032 		}
1033 		return;
1034 	}
1035 
1036 	// If a device was pending for deletion because its node went away but its bus info block
1037 	// and root directory header matches that of a newly discovered device, revive the
1038 	// existing fw_device. The newly allocated fw_device becomes obsolete instead.
1039 	//
1040 	// serialize config_rom access.
1041 	scoped_guard(rwsem_read, &fw_device_rwsem) {
1042 		found = device_find_child(card->device, (void *)device->config_rom,
1043 					  compare_configuration_rom);
1044 	}
1045 	if (found) {
1046 		struct fw_device *reused = fw_device(found);
1047 
1048 		if (atomic_cmpxchg(&reused->state,
1049 				   FW_DEVICE_GONE,
1050 				   FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
1051 			// serialize node access
1052 			scoped_guard(spinlock_irq, &card->lock) {
1053 				struct fw_node *current_node = device->node;
1054 				struct fw_node *obsolete_node = reused->node;
1055 
1056 				device->node = obsolete_node;
1057 				device->node->data = device;
1058 				reused->node = current_node;
1059 				reused->node->data = reused;
1060 
1061 				reused->max_speed = device->max_speed;
1062 				reused->node_id = current_node->node_id;
1063 				smp_wmb();  /* update node_id before generation */
1064 				reused->generation = card->generation;
1065 				reused->config_rom_retries = 0;
1066 				fw_notice(card, "rediscovered device %s\n",
1067 					  dev_name(found));
1068 
1069 				reused->workfn = fw_device_update;
1070 				fw_schedule_device_work(reused, 0);
1071 
1072 				if (current_node == card->root_node)
1073 					fw_schedule_bm_work(card, 0);
1074 			}
1075 
1076 			put_device(found);
1077 			fw_device_release(&device->device);
1078 
1079 			return;
1080 		}
1081 
1082 		put_device(found);
1083 	}
1084 
1085 	device_initialize(&device->device);
1086 
1087 	fw_device_get(device);
1088 
1089 	// The index of allocated entry is used for minor identifier of device node.
1090 	ret = xa_alloc(&fw_device_xa, &minor, device, XA_LIMIT(0, MINORMASK), GFP_KERNEL);
1091 	if (ret < 0)
1092 		goto error;
1093 
1094 	device->device.bus = &fw_bus_type;
1095 	device->device.type = &fw_device_type;
1096 	device->device.parent = card->device;
1097 	device->device.devt = MKDEV(fw_cdev_major, minor);
1098 	dev_set_name(&device->device, "fw%d", minor);
1099 
1100 	BUILD_BUG_ON(ARRAY_SIZE(device->attribute_group.attrs) <
1101 			ARRAY_SIZE(fw_device_attributes) +
1102 			ARRAY_SIZE(config_rom_attributes));
1103 	init_fw_attribute_group(&device->device,
1104 				fw_device_attributes,
1105 				&device->attribute_group);
1106 
1107 	if (device_add(&device->device)) {
1108 		fw_err(card, "failed to add device\n");
1109 		goto error_with_cdev;
1110 	}
1111 
1112 	create_units(device);
1113 
1114 	/*
1115 	 * Transition the device to running state.  If it got pulled
1116 	 * out from under us while we did the initialization work, we
1117 	 * have to shut down the device again here.  Normally, though,
1118 	 * fw_node_event will be responsible for shutting it down when
1119 	 * necessary.  We have to use the atomic cmpxchg here to avoid
1120 	 * racing with the FW_NODE_DESTROYED case in
1121 	 * fw_node_event().
1122 	 */
1123 	if (atomic_cmpxchg(&device->state,
1124 			   FW_DEVICE_INITIALIZING,
1125 			   FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
1126 		device->workfn = fw_device_shutdown;
1127 		fw_schedule_device_work(device, SHUTDOWN_DELAY);
1128 	} else {
1129 		fw_notice(card, "created device %s: GUID %08x%08x, S%d00\n",
1130 			  dev_name(&device->device),
1131 			  device->config_rom[3], device->config_rom[4],
1132 			  1 << device->max_speed);
1133 		device->config_rom_retries = 0;
1134 
1135 		set_broadcast_channel(device, device->generation);
1136 
1137 		add_device_randomness(&device->config_rom[3], 8);
1138 	}
1139 
1140 	/*
1141 	 * Reschedule the IRM work if we just finished reading the
1142 	 * root node config rom.  If this races with a bus reset we
1143 	 * just end up running the IRM work a couple of extra times -
1144 	 * pretty harmless.
1145 	 */
1146 	if (device->node == card->root_node)
1147 		fw_schedule_bm_work(card, 0);
1148 
1149 	return;
1150 
1151  error_with_cdev:
1152 	xa_erase(&fw_device_xa, minor);
1153  error:
1154 	fw_device_put(device);		// fw_device_xa's reference.
1155 
1156 	put_device(&device->device);	/* our reference */
1157 }
1158 
1159 /* Reread and compare bus info block and header of root directory */
1160 static int reread_config_rom(struct fw_device *device, int generation,
1161 			     bool *changed)
1162 {
1163 	u32 q;
1164 	int i, rcode;
1165 
1166 	for (i = 0; i < 6; i++) {
1167 		rcode = read_rom(device, generation, i, &q);
1168 		if (rcode != RCODE_COMPLETE)
1169 			return rcode;
1170 
1171 		if (i == 0 && q == 0)
1172 			/* inaccessible (see read_config_rom); retry later */
1173 			return RCODE_BUSY;
1174 
1175 		if (q != device->config_rom[i]) {
1176 			*changed = true;
1177 			return RCODE_COMPLETE;
1178 		}
1179 	}
1180 
1181 	*changed = false;
1182 	return RCODE_COMPLETE;
1183 }
1184 
1185 static void fw_device_refresh(struct work_struct *work)
1186 {
1187 	struct fw_device *device =
1188 		container_of(work, struct fw_device, work.work);
1189 	struct fw_card *card = device->card;
1190 	int ret, node_id = device->node_id;
1191 	bool changed;
1192 
1193 	ret = reread_config_rom(device, device->generation, &changed);
1194 	if (ret != RCODE_COMPLETE)
1195 		goto failed_config_rom;
1196 
1197 	if (!changed) {
1198 		if (atomic_cmpxchg(&device->state,
1199 				   FW_DEVICE_INITIALIZING,
1200 				   FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
1201 			goto gone;
1202 
1203 		fw_device_update(work);
1204 		device->config_rom_retries = 0;
1205 		goto out;
1206 	}
1207 
1208 	/*
1209 	 * Something changed.  We keep things simple and don't investigate
1210 	 * further.  We just destroy all previous units and create new ones.
1211 	 */
1212 	device_for_each_child(&device->device, NULL, shutdown_unit);
1213 
1214 	ret = read_config_rom(device, device->generation);
1215 	if (ret != RCODE_COMPLETE)
1216 		goto failed_config_rom;
1217 
1218 	fw_device_cdev_update(device);
1219 	create_units(device);
1220 
1221 	/* Userspace may want to re-read attributes. */
1222 	kobject_uevent(&device->device.kobj, KOBJ_CHANGE);
1223 
1224 	if (atomic_cmpxchg(&device->state,
1225 			   FW_DEVICE_INITIALIZING,
1226 			   FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
1227 		goto gone;
1228 
1229 	fw_notice(card, "refreshed device %s\n", dev_name(&device->device));
1230 	device->config_rom_retries = 0;
1231 	goto out;
1232 
1233  failed_config_rom:
1234 	if (device->config_rom_retries < MAX_RETRIES &&
1235 	    atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
1236 		device->config_rom_retries++;
1237 		fw_schedule_device_work(device, RETRY_DELAY);
1238 		return;
1239 	}
1240 
1241 	fw_notice(card, "giving up on refresh of device %s: %s\n",
1242 		  dev_name(&device->device), fw_rcode_string(ret));
1243  gone:
1244 	atomic_set(&device->state, FW_DEVICE_GONE);
1245 	device->workfn = fw_device_shutdown;
1246 	fw_schedule_device_work(device, SHUTDOWN_DELAY);
1247  out:
1248 	if (node_id == card->root_node->node_id)
1249 		fw_schedule_bm_work(card, 0);
1250 }
1251 
1252 static void fw_device_workfn(struct work_struct *work)
1253 {
1254 	struct fw_device *device = container_of(to_delayed_work(work),
1255 						struct fw_device, work);
1256 	device->workfn(work);
1257 }
1258 
1259 void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
1260 {
1261 	struct fw_device *device;
1262 
1263 	switch (event) {
1264 	case FW_NODE_CREATED:
1265 		/*
1266 		 * Attempt to scan the node, regardless whether its self ID has
1267 		 * the L (link active) flag set or not.  Some broken devices
1268 		 * send L=0 but have an up-and-running link; others send L=1
1269 		 * without actually having a link.
1270 		 */
1271  create:
1272 		device = kzalloc(sizeof(*device), GFP_ATOMIC);
1273 		if (device == NULL)
1274 			break;
1275 
1276 		/*
1277 		 * Do minimal initialization of the device here, the
1278 		 * rest will happen in fw_device_init().
1279 		 *
1280 		 * Attention:  A lot of things, even fw_device_get(),
1281 		 * cannot be done before fw_device_init() finished!
1282 		 * You can basically just check device->state and
1283 		 * schedule work until then, but only while holding
1284 		 * card->lock.
1285 		 */
1286 		atomic_set(&device->state, FW_DEVICE_INITIALIZING);
1287 		device->card = fw_card_get(card);
1288 		device->node = fw_node_get(node);
1289 		device->node_id = node->node_id;
1290 		device->generation = card->generation;
1291 		device->is_local = node == card->local_node;
1292 		mutex_init(&device->client_list_mutex);
1293 		INIT_LIST_HEAD(&device->client_list);
1294 
1295 		/*
1296 		 * Set the node data to point back to this device so
1297 		 * FW_NODE_UPDATED callbacks can update the node_id
1298 		 * and generation for the device.
1299 		 */
1300 		node->data = device;
1301 
1302 		/*
1303 		 * Many devices are slow to respond after bus resets,
1304 		 * especially if they are bus powered and go through
1305 		 * power-up after getting plugged in.  We schedule the
1306 		 * first config rom scan half a second after bus reset.
1307 		 */
1308 		device->workfn = fw_device_init;
1309 		INIT_DELAYED_WORK(&device->work, fw_device_workfn);
1310 		fw_schedule_device_work(device, INITIAL_DELAY);
1311 		break;
1312 
1313 	case FW_NODE_INITIATED_RESET:
1314 	case FW_NODE_LINK_ON:
1315 		device = node->data;
1316 		if (device == NULL)
1317 			goto create;
1318 
1319 		device->node_id = node->node_id;
1320 		smp_wmb();  /* update node_id before generation */
1321 		device->generation = card->generation;
1322 		if (atomic_cmpxchg(&device->state,
1323 			    FW_DEVICE_RUNNING,
1324 			    FW_DEVICE_INITIALIZING) == FW_DEVICE_RUNNING) {
1325 			device->workfn = fw_device_refresh;
1326 			fw_schedule_device_work(device,
1327 				device->is_local ? 0 : INITIAL_DELAY);
1328 		}
1329 		break;
1330 
1331 	case FW_NODE_UPDATED:
1332 		device = node->data;
1333 		if (device == NULL)
1334 			break;
1335 
1336 		device->node_id = node->node_id;
1337 		smp_wmb();  /* update node_id before generation */
1338 		device->generation = card->generation;
1339 		if (atomic_read(&device->state) == FW_DEVICE_RUNNING) {
1340 			device->workfn = fw_device_update;
1341 			fw_schedule_device_work(device, 0);
1342 		}
1343 		break;
1344 
1345 	case FW_NODE_DESTROYED:
1346 	case FW_NODE_LINK_OFF:
1347 		if (!node->data)
1348 			break;
1349 
1350 		/*
1351 		 * Destroy the device associated with the node.  There
1352 		 * are two cases here: either the device is fully
1353 		 * initialized (FW_DEVICE_RUNNING) or we're in the
1354 		 * process of reading its config rom
1355 		 * (FW_DEVICE_INITIALIZING).  If it is fully
1356 		 * initialized we can reuse device->work to schedule a
1357 		 * full fw_device_shutdown().  If not, there's work
1358 		 * scheduled to read it's config rom, and we just put
1359 		 * the device in shutdown state to have that code fail
1360 		 * to create the device.
1361 		 */
1362 		device = node->data;
1363 		if (atomic_xchg(&device->state,
1364 				FW_DEVICE_GONE) == FW_DEVICE_RUNNING) {
1365 			device->workfn = fw_device_shutdown;
1366 			fw_schedule_device_work(device,
1367 				list_empty(&card->link) ? 0 : SHUTDOWN_DELAY);
1368 		}
1369 		break;
1370 	}
1371 }
1372 
1373 #ifdef CONFIG_FIREWIRE_KUNIT_DEVICE_ATTRIBUTE_TEST
1374 #include "device-attribute-test.c"
1375 #endif
1376