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