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