[SCTP]: Add RCU synchronization around sctp_localaddr_list
[linux-2.6.git] / drivers / firewire / fw-device.c
blob2b6586341635b9ed57dafc5f6ebb977924177010
1 /*
2 * Device probing and sysfs code.
4 * Copyright (C) 2005-2006 Kristian Hoegsberg <krh@bitplanet.net>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software Foundation,
18 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21 #include <linux/module.h>
22 #include <linux/wait.h>
23 #include <linux/errno.h>
24 #include <linux/kthread.h>
25 #include <linux/device.h>
26 #include <linux/delay.h>
27 #include <linux/idr.h>
28 #include <linux/rwsem.h>
29 #include <asm/semaphore.h>
30 #include <linux/ctype.h>
31 #include "fw-transaction.h"
32 #include "fw-topology.h"
33 #include "fw-device.h"
35 void fw_csr_iterator_init(struct fw_csr_iterator *ci, u32 * p)
37 ci->p = p + 1;
38 ci->end = ci->p + (p[0] >> 16);
40 EXPORT_SYMBOL(fw_csr_iterator_init);
42 int fw_csr_iterator_next(struct fw_csr_iterator *ci, int *key, int *value)
44 *key = *ci->p >> 24;
45 *value = *ci->p & 0xffffff;
47 return ci->p++ < ci->end;
49 EXPORT_SYMBOL(fw_csr_iterator_next);
51 static int is_fw_unit(struct device *dev);
53 static int match_unit_directory(u32 * directory, const struct fw_device_id *id)
55 struct fw_csr_iterator ci;
56 int key, value, match;
58 match = 0;
59 fw_csr_iterator_init(&ci, directory);
60 while (fw_csr_iterator_next(&ci, &key, &value)) {
61 if (key == CSR_VENDOR && value == id->vendor)
62 match |= FW_MATCH_VENDOR;
63 if (key == CSR_MODEL && value == id->model)
64 match |= FW_MATCH_MODEL;
65 if (key == CSR_SPECIFIER_ID && value == id->specifier_id)
66 match |= FW_MATCH_SPECIFIER_ID;
67 if (key == CSR_VERSION && value == id->version)
68 match |= FW_MATCH_VERSION;
71 return (match & id->match_flags) == id->match_flags;
74 static int fw_unit_match(struct device *dev, struct device_driver *drv)
76 struct fw_unit *unit = fw_unit(dev);
77 struct fw_driver *driver = fw_driver(drv);
78 int i;
80 /* We only allow binding to fw_units. */
81 if (!is_fw_unit(dev))
82 return 0;
84 for (i = 0; driver->id_table[i].match_flags != 0; i++) {
85 if (match_unit_directory(unit->directory, &driver->id_table[i]))
86 return 1;
89 return 0;
92 static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
94 struct fw_device *device = fw_device(unit->device.parent);
95 struct fw_csr_iterator ci;
97 int key, value;
98 int vendor = 0;
99 int model = 0;
100 int specifier_id = 0;
101 int version = 0;
103 fw_csr_iterator_init(&ci, &device->config_rom[5]);
104 while (fw_csr_iterator_next(&ci, &key, &value)) {
105 switch (key) {
106 case CSR_VENDOR:
107 vendor = value;
108 break;
109 case CSR_MODEL:
110 model = value;
111 break;
115 fw_csr_iterator_init(&ci, unit->directory);
116 while (fw_csr_iterator_next(&ci, &key, &value)) {
117 switch (key) {
118 case CSR_SPECIFIER_ID:
119 specifier_id = value;
120 break;
121 case CSR_VERSION:
122 version = value;
123 break;
127 return snprintf(buffer, buffer_size,
128 "ieee1394:ven%08Xmo%08Xsp%08Xver%08X",
129 vendor, model, specifier_id, version);
132 static int
133 fw_unit_uevent(struct device *dev, char **envp, int num_envp,
134 char *buffer, int buffer_size)
136 struct fw_unit *unit = fw_unit(dev);
137 char modalias[64];
138 int length = 0;
139 int i = 0;
141 get_modalias(unit, modalias, sizeof(modalias));
143 if (add_uevent_var(envp, num_envp, &i,
144 buffer, buffer_size, &length,
145 "MODALIAS=%s", modalias))
146 return -ENOMEM;
148 envp[i] = NULL;
150 return 0;
153 struct bus_type fw_bus_type = {
154 .name = "firewire",
155 .match = fw_unit_match,
157 EXPORT_SYMBOL(fw_bus_type);
159 struct fw_device *fw_device_get(struct fw_device *device)
161 get_device(&device->device);
163 return device;
166 void fw_device_put(struct fw_device *device)
168 put_device(&device->device);
171 static void fw_device_release(struct device *dev)
173 struct fw_device *device = fw_device(dev);
174 unsigned long flags;
177 * Take the card lock so we don't set this to NULL while a
178 * FW_NODE_UPDATED callback is being handled.
180 spin_lock_irqsave(&device->card->lock, flags);
181 device->node->data = NULL;
182 spin_unlock_irqrestore(&device->card->lock, flags);
184 fw_node_put(device->node);
185 fw_card_put(device->card);
186 kfree(device->config_rom);
187 kfree(device);
190 int fw_device_enable_phys_dma(struct fw_device *device)
192 return device->card->driver->enable_phys_dma(device->card,
193 device->node_id,
194 device->generation);
196 EXPORT_SYMBOL(fw_device_enable_phys_dma);
198 struct config_rom_attribute {
199 struct device_attribute attr;
200 u32 key;
203 static ssize_t
204 show_immediate(struct device *dev, struct device_attribute *dattr, char *buf)
206 struct config_rom_attribute *attr =
207 container_of(dattr, struct config_rom_attribute, attr);
208 struct fw_csr_iterator ci;
209 u32 *dir;
210 int key, value;
212 if (is_fw_unit(dev))
213 dir = fw_unit(dev)->directory;
214 else
215 dir = fw_device(dev)->config_rom + 5;
217 fw_csr_iterator_init(&ci, dir);
218 while (fw_csr_iterator_next(&ci, &key, &value))
219 if (attr->key == key)
220 return snprintf(buf, buf ? PAGE_SIZE : 0,
221 "0x%06x\n", value);
223 return -ENOENT;
226 #define IMMEDIATE_ATTR(name, key) \
227 { __ATTR(name, S_IRUGO, show_immediate, NULL), key }
229 static ssize_t
230 show_text_leaf(struct device *dev, struct device_attribute *dattr, char *buf)
232 struct config_rom_attribute *attr =
233 container_of(dattr, struct config_rom_attribute, attr);
234 struct fw_csr_iterator ci;
235 u32 *dir, *block = NULL, *p, *end;
236 int length, key, value, last_key = 0;
237 char *b;
239 if (is_fw_unit(dev))
240 dir = fw_unit(dev)->directory;
241 else
242 dir = fw_device(dev)->config_rom + 5;
244 fw_csr_iterator_init(&ci, dir);
245 while (fw_csr_iterator_next(&ci, &key, &value)) {
246 if (attr->key == last_key &&
247 key == (CSR_DESCRIPTOR | CSR_LEAF))
248 block = ci.p - 1 + value;
249 last_key = key;
252 if (block == NULL)
253 return -ENOENT;
255 length = min(block[0] >> 16, 256U);
256 if (length < 3)
257 return -ENOENT;
259 if (block[1] != 0 || block[2] != 0)
260 /* Unknown encoding. */
261 return -ENOENT;
263 if (buf == NULL)
264 return length * 4;
266 b = buf;
267 end = &block[length + 1];
268 for (p = &block[3]; p < end; p++, b += 4)
269 * (u32 *) b = (__force u32) __cpu_to_be32(*p);
271 /* Strip trailing whitespace and add newline. */
272 while (b--, (isspace(*b) || *b == '\0') && b > buf);
273 strcpy(b + 1, "\n");
275 return b + 2 - buf;
278 #define TEXT_LEAF_ATTR(name, key) \
279 { __ATTR(name, S_IRUGO, show_text_leaf, NULL), key }
281 static struct config_rom_attribute config_rom_attributes[] = {
282 IMMEDIATE_ATTR(vendor, CSR_VENDOR),
283 IMMEDIATE_ATTR(hardware_version, CSR_HARDWARE_VERSION),
284 IMMEDIATE_ATTR(specifier_id, CSR_SPECIFIER_ID),
285 IMMEDIATE_ATTR(version, CSR_VERSION),
286 IMMEDIATE_ATTR(model, CSR_MODEL),
287 TEXT_LEAF_ATTR(vendor_name, CSR_VENDOR),
288 TEXT_LEAF_ATTR(model_name, CSR_MODEL),
289 TEXT_LEAF_ATTR(hardware_version_name, CSR_HARDWARE_VERSION),
292 static void
293 init_fw_attribute_group(struct device *dev,
294 struct device_attribute *attrs,
295 struct fw_attribute_group *group)
297 struct device_attribute *attr;
298 int i, j;
300 for (j = 0; attrs[j].attr.name != NULL; j++)
301 group->attrs[j] = &attrs[j].attr;
303 for (i = 0; i < ARRAY_SIZE(config_rom_attributes); i++) {
304 attr = &config_rom_attributes[i].attr;
305 if (attr->show(dev, attr, NULL) < 0)
306 continue;
307 group->attrs[j++] = &attr->attr;
310 BUG_ON(j >= ARRAY_SIZE(group->attrs));
311 group->attrs[j++] = NULL;
312 group->groups[0] = &group->group;
313 group->groups[1] = NULL;
314 group->group.attrs = group->attrs;
315 dev->groups = group->groups;
318 static ssize_t
319 modalias_show(struct device *dev,
320 struct device_attribute *attr, char *buf)
322 struct fw_unit *unit = fw_unit(dev);
323 int length;
325 length = get_modalias(unit, buf, PAGE_SIZE);
326 strcpy(buf + length, "\n");
328 return length + 1;
331 static ssize_t
332 rom_index_show(struct device *dev,
333 struct device_attribute *attr, char *buf)
335 struct fw_device *device = fw_device(dev->parent);
336 struct fw_unit *unit = fw_unit(dev);
338 return snprintf(buf, PAGE_SIZE, "%d\n",
339 (int)(unit->directory - device->config_rom));
342 static struct device_attribute fw_unit_attributes[] = {
343 __ATTR_RO(modalias),
344 __ATTR_RO(rom_index),
345 __ATTR_NULL,
348 static ssize_t
349 config_rom_show(struct device *dev, struct device_attribute *attr, char *buf)
351 struct fw_device *device = fw_device(dev);
353 memcpy(buf, device->config_rom, device->config_rom_length * 4);
355 return device->config_rom_length * 4;
358 static ssize_t
359 guid_show(struct device *dev, struct device_attribute *attr, char *buf)
361 struct fw_device *device = fw_device(dev);
362 u64 guid;
364 guid = ((u64)device->config_rom[3] << 32) | device->config_rom[4];
366 return snprintf(buf, PAGE_SIZE, "0x%016llx\n",
367 (unsigned long long)guid);
370 static struct device_attribute fw_device_attributes[] = {
371 __ATTR_RO(config_rom),
372 __ATTR_RO(guid),
373 __ATTR_NULL,
376 struct read_quadlet_callback_data {
377 struct completion done;
378 int rcode;
379 u32 data;
382 static void
383 complete_transaction(struct fw_card *card, int rcode,
384 void *payload, size_t length, void *data)
386 struct read_quadlet_callback_data *callback_data = data;
388 if (rcode == RCODE_COMPLETE)
389 callback_data->data = be32_to_cpu(*(__be32 *)payload);
390 callback_data->rcode = rcode;
391 complete(&callback_data->done);
394 static int read_rom(struct fw_device *device, int index, u32 * data)
396 struct read_quadlet_callback_data callback_data;
397 struct fw_transaction t;
398 u64 offset;
400 init_completion(&callback_data.done);
402 offset = 0xfffff0000400ULL + index * 4;
403 fw_send_request(device->card, &t, TCODE_READ_QUADLET_REQUEST,
404 device->node_id, device->generation, device->max_speed,
405 offset, NULL, 4, complete_transaction, &callback_data);
407 wait_for_completion(&callback_data.done);
409 *data = callback_data.data;
411 return callback_data.rcode;
414 static int read_bus_info_block(struct fw_device *device)
416 static u32 rom[256];
417 u32 stack[16], sp, key;
418 int i, end, length;
420 device->max_speed = SCODE_100;
422 /* First read the bus info block. */
423 for (i = 0; i < 5; i++) {
424 if (read_rom(device, i, &rom[i]) != RCODE_COMPLETE)
425 return -1;
427 * As per IEEE1212 7.2, during power-up, devices can
428 * reply with a 0 for the first quadlet of the config
429 * rom to indicate that they are booting (for example,
430 * if the firmware is on the disk of a external
431 * harddisk). In that case we just fail, and the
432 * retry mechanism will try again later.
434 if (i == 0 && rom[i] == 0)
435 return -1;
438 device->max_speed = device->node->max_speed;
441 * Determine the speed of
442 * - devices with link speed less than PHY speed,
443 * - devices with 1394b PHY (unless only connected to 1394a PHYs),
444 * - all devices if there are 1394b repeaters.
445 * Note, we cannot use the bus info block's link_spd as starting point
446 * because some buggy firmwares set it lower than necessary and because
447 * 1394-1995 nodes do not have the field.
449 if ((rom[2] & 0x7) < device->max_speed ||
450 device->max_speed == SCODE_BETA ||
451 device->card->beta_repeaters_present) {
452 u32 dummy;
454 /* for S1600 and S3200 */
455 if (device->max_speed == SCODE_BETA)
456 device->max_speed = device->card->link_speed;
458 while (device->max_speed > SCODE_100) {
459 if (read_rom(device, 0, &dummy) == RCODE_COMPLETE)
460 break;
461 device->max_speed--;
466 * Now parse the config rom. The config rom is a recursive
467 * directory structure so we parse it using a stack of
468 * references to the blocks that make up the structure. We
469 * push a reference to the root directory on the stack to
470 * start things off.
472 length = i;
473 sp = 0;
474 stack[sp++] = 0xc0000005;
475 while (sp > 0) {
477 * Pop the next block reference of the stack. The
478 * lower 24 bits is the offset into the config rom,
479 * the upper 8 bits are the type of the reference the
480 * block.
482 key = stack[--sp];
483 i = key & 0xffffff;
484 if (i >= ARRAY_SIZE(rom))
486 * The reference points outside the standard
487 * config rom area, something's fishy.
489 return -1;
491 /* Read header quadlet for the block to get the length. */
492 if (read_rom(device, i, &rom[i]) != RCODE_COMPLETE)
493 return -1;
494 end = i + (rom[i] >> 16) + 1;
495 i++;
496 if (end > ARRAY_SIZE(rom))
498 * This block extends outside standard config
499 * area (and the array we're reading it
500 * into). That's broken, so ignore this
501 * device.
503 return -1;
506 * Now read in the block. If this is a directory
507 * block, check the entries as we read them to see if
508 * it references another block, and push it in that case.
510 while (i < end) {
511 if (read_rom(device, i, &rom[i]) != RCODE_COMPLETE)
512 return -1;
513 if ((key >> 30) == 3 && (rom[i] >> 30) > 1 &&
514 sp < ARRAY_SIZE(stack))
515 stack[sp++] = i + rom[i];
516 i++;
518 if (length < i)
519 length = i;
522 device->config_rom = kmalloc(length * 4, GFP_KERNEL);
523 if (device->config_rom == NULL)
524 return -1;
525 memcpy(device->config_rom, rom, length * 4);
526 device->config_rom_length = length;
528 return 0;
531 static void fw_unit_release(struct device *dev)
533 struct fw_unit *unit = fw_unit(dev);
535 kfree(unit);
538 static struct device_type fw_unit_type = {
539 .uevent = fw_unit_uevent,
540 .release = fw_unit_release,
543 static int is_fw_unit(struct device *dev)
545 return dev->type == &fw_unit_type;
548 static void create_units(struct fw_device *device)
550 struct fw_csr_iterator ci;
551 struct fw_unit *unit;
552 int key, value, i;
554 i = 0;
555 fw_csr_iterator_init(&ci, &device->config_rom[5]);
556 while (fw_csr_iterator_next(&ci, &key, &value)) {
557 if (key != (CSR_UNIT | CSR_DIRECTORY))
558 continue;
561 * Get the address of the unit directory and try to
562 * match the drivers id_tables against it.
564 unit = kzalloc(sizeof(*unit), GFP_KERNEL);
565 if (unit == NULL) {
566 fw_error("failed to allocate memory for unit\n");
567 continue;
570 unit->directory = ci.p + value - 1;
571 unit->device.bus = &fw_bus_type;
572 unit->device.type = &fw_unit_type;
573 unit->device.parent = &device->device;
574 snprintf(unit->device.bus_id, sizeof(unit->device.bus_id),
575 "%s.%d", device->device.bus_id, i++);
577 init_fw_attribute_group(&unit->device,
578 fw_unit_attributes,
579 &unit->attribute_group);
580 if (device_register(&unit->device) < 0)
581 goto skip_unit;
583 continue;
585 skip_unit:
586 kfree(unit);
590 static int shutdown_unit(struct device *device, void *data)
592 device_unregister(device);
594 return 0;
597 static DECLARE_RWSEM(idr_rwsem);
598 static DEFINE_IDR(fw_device_idr);
599 int fw_cdev_major;
601 struct fw_device *fw_device_from_devt(dev_t devt)
603 struct fw_device *device;
605 down_read(&idr_rwsem);
606 device = idr_find(&fw_device_idr, MINOR(devt));
607 up_read(&idr_rwsem);
609 return device;
612 static void fw_device_shutdown(struct work_struct *work)
614 struct fw_device *device =
615 container_of(work, struct fw_device, work.work);
616 int minor = MINOR(device->device.devt);
618 down_write(&idr_rwsem);
619 idr_remove(&fw_device_idr, minor);
620 up_write(&idr_rwsem);
622 fw_device_cdev_remove(device);
623 device_for_each_child(&device->device, NULL, shutdown_unit);
624 device_unregister(&device->device);
627 static struct device_type fw_device_type = {
628 .release = fw_device_release,
632 * These defines control the retry behavior for reading the config
633 * rom. It shouldn't be necessary to tweak these; if the device
634 * doesn't respond to a config rom read within 10 seconds, it's not
635 * going to respond at all. As for the initial delay, a lot of
636 * devices will be able to respond within half a second after bus
637 * reset. On the other hand, it's not really worth being more
638 * aggressive than that, since it scales pretty well; if 10 devices
639 * are plugged in, they're all getting read within one second.
642 #define MAX_RETRIES 10
643 #define RETRY_DELAY (3 * HZ)
644 #define INITIAL_DELAY (HZ / 2)
646 static void fw_device_init(struct work_struct *work)
648 struct fw_device *device =
649 container_of(work, struct fw_device, work.work);
650 int minor, err;
653 * All failure paths here set node->data to NULL, so that we
654 * don't try to do device_for_each_child() on a kfree()'d
655 * device.
658 if (read_bus_info_block(device) < 0) {
659 if (device->config_rom_retries < MAX_RETRIES) {
660 device->config_rom_retries++;
661 schedule_delayed_work(&device->work, RETRY_DELAY);
662 } else {
663 fw_notify("giving up on config rom for node id %x\n",
664 device->node_id);
665 if (device->node == device->card->root_node)
666 schedule_delayed_work(&device->card->work, 0);
667 fw_device_release(&device->device);
669 return;
672 err = -ENOMEM;
673 down_write(&idr_rwsem);
674 if (idr_pre_get(&fw_device_idr, GFP_KERNEL))
675 err = idr_get_new(&fw_device_idr, device, &minor);
676 up_write(&idr_rwsem);
677 if (err < 0)
678 goto error;
680 device->device.bus = &fw_bus_type;
681 device->device.type = &fw_device_type;
682 device->device.parent = device->card->device;
683 device->device.devt = MKDEV(fw_cdev_major, minor);
684 snprintf(device->device.bus_id, sizeof(device->device.bus_id),
685 "fw%d", minor);
687 init_fw_attribute_group(&device->device,
688 fw_device_attributes,
689 &device->attribute_group);
690 if (device_add(&device->device)) {
691 fw_error("Failed to add device.\n");
692 goto error_with_cdev;
695 create_units(device);
698 * Transition the device to running state. If it got pulled
699 * out from under us while we did the intialization work, we
700 * have to shut down the device again here. Normally, though,
701 * fw_node_event will be responsible for shutting it down when
702 * necessary. We have to use the atomic cmpxchg here to avoid
703 * racing with the FW_NODE_DESTROYED case in
704 * fw_node_event().
706 if (atomic_cmpxchg(&device->state,
707 FW_DEVICE_INITIALIZING,
708 FW_DEVICE_RUNNING) == FW_DEVICE_SHUTDOWN)
709 fw_device_shutdown(&device->work.work);
710 else
711 fw_notify("created new fw device %s "
712 "(%d config rom retries, S%d00)\n",
713 device->device.bus_id, device->config_rom_retries,
714 1 << device->max_speed);
717 * Reschedule the IRM work if we just finished reading the
718 * root node config rom. If this races with a bus reset we
719 * just end up running the IRM work a couple of extra times -
720 * pretty harmless.
722 if (device->node == device->card->root_node)
723 schedule_delayed_work(&device->card->work, 0);
725 return;
727 error_with_cdev:
728 down_write(&idr_rwsem);
729 idr_remove(&fw_device_idr, minor);
730 up_write(&idr_rwsem);
731 error:
732 put_device(&device->device);
735 static int update_unit(struct device *dev, void *data)
737 struct fw_unit *unit = fw_unit(dev);
738 struct fw_driver *driver = (struct fw_driver *)dev->driver;
740 if (is_fw_unit(dev) && driver != NULL && driver->update != NULL) {
741 down(&dev->sem);
742 driver->update(unit);
743 up(&dev->sem);
746 return 0;
749 static void fw_device_update(struct work_struct *work)
751 struct fw_device *device =
752 container_of(work, struct fw_device, work.work);
754 fw_device_cdev_update(device);
755 device_for_each_child(&device->device, NULL, update_unit);
758 void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
760 struct fw_device *device;
762 switch (event) {
763 case FW_NODE_CREATED:
764 case FW_NODE_LINK_ON:
765 if (!node->link_on)
766 break;
768 device = kzalloc(sizeof(*device), GFP_ATOMIC);
769 if (device == NULL)
770 break;
773 * Do minimal intialization of the device here, the
774 * rest will happen in fw_device_init(). We need the
775 * card and node so we can read the config rom and we
776 * need to do device_initialize() now so
777 * device_for_each_child() in FW_NODE_UPDATED is
778 * doesn't freak out.
780 device_initialize(&device->device);
781 atomic_set(&device->state, FW_DEVICE_INITIALIZING);
782 device->card = fw_card_get(card);
783 device->node = fw_node_get(node);
784 device->node_id = node->node_id;
785 device->generation = card->generation;
786 INIT_LIST_HEAD(&device->client_list);
789 * Set the node data to point back to this device so
790 * FW_NODE_UPDATED callbacks can update the node_id
791 * and generation for the device.
793 node->data = device;
796 * Many devices are slow to respond after bus resets,
797 * especially if they are bus powered and go through
798 * power-up after getting plugged in. We schedule the
799 * first config rom scan half a second after bus reset.
801 INIT_DELAYED_WORK(&device->work, fw_device_init);
802 schedule_delayed_work(&device->work, INITIAL_DELAY);
803 break;
805 case FW_NODE_UPDATED:
806 if (!node->link_on || node->data == NULL)
807 break;
809 device = node->data;
810 device->node_id = node->node_id;
811 device->generation = card->generation;
812 if (atomic_read(&device->state) == FW_DEVICE_RUNNING) {
813 PREPARE_DELAYED_WORK(&device->work, fw_device_update);
814 schedule_delayed_work(&device->work, 0);
816 break;
818 case FW_NODE_DESTROYED:
819 case FW_NODE_LINK_OFF:
820 if (!node->data)
821 break;
824 * Destroy the device associated with the node. There
825 * are two cases here: either the device is fully
826 * initialized (FW_DEVICE_RUNNING) or we're in the
827 * process of reading its config rom
828 * (FW_DEVICE_INITIALIZING). If it is fully
829 * initialized we can reuse device->work to schedule a
830 * full fw_device_shutdown(). If not, there's work
831 * scheduled to read it's config rom, and we just put
832 * the device in shutdown state to have that code fail
833 * to create the device.
835 device = node->data;
836 if (atomic_xchg(&device->state,
837 FW_DEVICE_SHUTDOWN) == FW_DEVICE_RUNNING) {
838 PREPARE_DELAYED_WORK(&device->work, fw_device_shutdown);
839 schedule_delayed_work(&device->work, 0);
841 break;