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