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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Device probing and sysfs code.
4 *
5 * Copyright (C) 2005-2006 Kristian Hoegsberg <krh@bitplanet.net>
6 */
7
8#include <linux/bug.h>
9#include <linux/ctype.h>
10#include <linux/delay.h>
11#include <linux/device.h>
12#include <linux/errno.h>
13#include <linux/firewire.h>
14#include <linux/firewire-constants.h>
15#include <linux/idr.h>
16#include <linux/jiffies.h>
17#include <linux/kobject.h>
18#include <linux/list.h>
19#include <linux/mod_devicetable.h>
20#include <linux/module.h>
21#include <linux/mutex.h>
22#include <linux/random.h>
23#include <linux/rwsem.h>
24#include <linux/slab.h>
25#include <linux/spinlock.h>
26#include <linux/string.h>
27#include <linux/workqueue.h>
28
29#include <linux/atomic.h>
30#include <asm/byteorder.h>
31
32#include "core.h"
33
34#define ROOT_DIR_OFFSET 5
35
36void fw_csr_iterator_init(struct fw_csr_iterator *ci, const u32 *p)
37{
38 ci->p = p + 1;
39 ci->end = ci->p + (p[0] >> 16);
40}
41EXPORT_SYMBOL(fw_csr_iterator_init);
42
43int fw_csr_iterator_next(struct fw_csr_iterator *ci, int *key, int *value)
44{
45 *key = *ci->p >> 24;
46 *value = *ci->p & 0xffffff;
47
48 return ci->p++ < ci->end;
49}
50EXPORT_SYMBOL(fw_csr_iterator_next);
51
52static const u32 *search_directory(const u32 *directory, int search_key)
53{
54 struct fw_csr_iterator ci;
55 int key, value;
56
57 search_key |= CSR_DIRECTORY;
58
59 fw_csr_iterator_init(&ci, directory);
60 while (fw_csr_iterator_next(&ci, &key, &value)) {
61 if (key == search_key)
62 return ci.p - 1 + value;
63 }
64
65 return NULL;
66}
67
68static const u32 *search_leaf(const u32 *directory, int search_key)
69{
70 struct fw_csr_iterator ci;
71 int last_key = 0, key, value;
72
73 fw_csr_iterator_init(&ci, directory);
74 while (fw_csr_iterator_next(&ci, &key, &value)) {
75 if (last_key == search_key &&
76 key == (CSR_DESCRIPTOR | CSR_LEAF))
77 return ci.p - 1 + value;
78
79 last_key = key;
80 }
81
82 return NULL;
83}
84
85static int textual_leaf_to_string(const u32 *block, char *buf, size_t size)
86{
87 unsigned int quadlets, i;
88 char c;
89
90 if (!size || !buf)
91 return -EINVAL;
92
93 quadlets = min(block[0] >> 16, 256U);
94 if (quadlets < 2)
95 return -ENODATA;
96
97 if (block[1] != 0 || block[2] != 0)
98 /* unknown language/character set */
99 return -ENODATA;
100
101 block += 3;
102 quadlets -= 2;
103 for (i = 0; i < quadlets * 4 && i < size - 1; i++) {
104 c = block[i / 4] >> (24 - 8 * (i % 4));
105 if (c == '\0')
106 break;
107 buf[i] = c;
108 }
109 buf[i] = '\0';
110
111 return i;
112}
113
114/**
115 * fw_csr_string() - reads a string from the configuration ROM
116 * @directory: e.g. root directory or unit directory
117 * @key: the key of the preceding directory entry
118 * @buf: where to put the string
119 * @size: size of @buf, in bytes
120 *
121 * The string is taken from a minimal ASCII text descriptor leaf just after the entry with the
122 * @key. The string is zero-terminated. An overlong string is silently truncated such that it
123 * and the zero byte fit into @size.
124 *
125 * Returns strlen(buf) or a negative error code.
126 */
127int fw_csr_string(const u32 *directory, int key, char *buf, size_t size)
128{
129 const u32 *leaf = search_leaf(directory, key);
130 if (!leaf)
131 return -ENOENT;
132
133 return textual_leaf_to_string(leaf, buf, size);
134}
135EXPORT_SYMBOL(fw_csr_string);
136
137static void get_ids(const u32 *directory, int *id)
138{
139 struct fw_csr_iterator ci;
140 int key, value;
141
142 fw_csr_iterator_init(&ci, directory);
143 while (fw_csr_iterator_next(&ci, &key, &value)) {
144 switch (key) {
145 case CSR_VENDOR: id[0] = value; break;
146 case CSR_MODEL: id[1] = value; break;
147 case CSR_SPECIFIER_ID: id[2] = value; break;
148 case CSR_VERSION: id[3] = value; break;
149 }
150 }
151}
152
153static void get_modalias_ids(const struct fw_unit *unit, int *id)
154{
155 const u32 *root_directory = &fw_parent_device(unit)->config_rom[ROOT_DIR_OFFSET];
156 const u32 *directories[] = {NULL, NULL, NULL};
157 const u32 *vendor_directory;
158 int i;
159
160 directories[0] = root_directory;
161
162 // Legacy layout of configuration ROM described in Annex 1 of 'Configuration ROM for AV/C
163 // Devices 1.0 (December 12, 2000, 1394 Trading Association, TA Document 1999027)'.
164 vendor_directory = search_directory(root_directory, CSR_VENDOR);
165 if (!vendor_directory) {
166 directories[1] = unit->directory;
167 } else {
168 directories[1] = vendor_directory;
169 directories[2] = unit->directory;
170 }
171
172 for (i = 0; i < ARRAY_SIZE(directories) && !!directories[i]; ++i)
173 get_ids(directories[i], id);
174}
175
176static bool match_ids(const struct ieee1394_device_id *id_table, int *id)
177{
178 int match = 0;
179
180 if (id[0] == id_table->vendor_id)
181 match |= IEEE1394_MATCH_VENDOR_ID;
182 if (id[1] == id_table->model_id)
183 match |= IEEE1394_MATCH_MODEL_ID;
184 if (id[2] == id_table->specifier_id)
185 match |= IEEE1394_MATCH_SPECIFIER_ID;
186 if (id[3] == id_table->version)
187 match |= IEEE1394_MATCH_VERSION;
188
189 return (match & id_table->match_flags) == id_table->match_flags;
190}
191
192static const struct ieee1394_device_id *unit_match(struct device *dev,
193 struct device_driver *drv)
194{
195 const struct ieee1394_device_id *id_table =
196 container_of(drv, struct fw_driver, driver)->id_table;
197 int id[] = {0, 0, 0, 0};
198
199 get_modalias_ids(fw_unit(dev), id);
200
201 for (; id_table->match_flags != 0; id_table++)
202 if (match_ids(id_table, id))
203 return id_table;
204
205 return NULL;
206}
207
208static bool is_fw_unit(const struct device *dev);
209
210static int fw_unit_match(struct device *dev, struct device_driver *drv)
211{
212 /* We only allow binding to fw_units. */
213 return is_fw_unit(dev) && unit_match(dev, drv) != NULL;
214}
215
216static int fw_unit_probe(struct device *dev)
217{
218 struct fw_driver *driver =
219 container_of(dev->driver, struct fw_driver, driver);
220
221 return driver->probe(fw_unit(dev), unit_match(dev, dev->driver));
222}
223
224static void fw_unit_remove(struct device *dev)
225{
226 struct fw_driver *driver =
227 container_of(dev->driver, struct fw_driver, driver);
228
229 driver->remove(fw_unit(dev));
230}
231
232static int get_modalias(const struct fw_unit *unit, char *buffer, size_t buffer_size)
233{
234 int id[] = {0, 0, 0, 0};
235
236 get_modalias_ids(unit, id);
237
238 return snprintf(buffer, buffer_size,
239 "ieee1394:ven%08Xmo%08Xsp%08Xver%08X",
240 id[0], id[1], id[2], id[3]);
241}
242
243static int fw_unit_uevent(const struct device *dev, struct kobj_uevent_env *env)
244{
245 const struct fw_unit *unit = fw_unit(dev);
246 char modalias[64];
247
248 get_modalias(unit, modalias, sizeof(modalias));
249
250 if (add_uevent_var(env, "MODALIAS=%s", modalias))
251 return -ENOMEM;
252
253 return 0;
254}
255
256const struct bus_type fw_bus_type = {
257 .name = "firewire",
258 .match = fw_unit_match,
259 .probe = fw_unit_probe,
260 .remove = fw_unit_remove,
261};
262EXPORT_SYMBOL(fw_bus_type);
263
264int fw_device_enable_phys_dma(struct fw_device *device)
265{
266 int generation = device->generation;
267
268 /* device->node_id, accessed below, must not be older than generation */
269 smp_rmb();
270
271 return device->card->driver->enable_phys_dma(device->card,
272 device->node_id,
273 generation);
274}
275EXPORT_SYMBOL(fw_device_enable_phys_dma);
276
277struct config_rom_attribute {
278 struct device_attribute attr;
279 u32 key;
280};
281
282static ssize_t show_immediate(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 struct fw_csr_iterator ci;
288 const u32 *directories[] = {NULL, NULL};
289 int i, value = -1;
290
291 down_read(&fw_device_rwsem);
292
293 if (is_fw_unit(dev)) {
294 directories[0] = fw_unit(dev)->directory;
295 } else {
296 const u32 *root_directory = fw_device(dev)->config_rom + ROOT_DIR_OFFSET;
297 const u32 *vendor_directory = search_directory(root_directory, CSR_VENDOR);
298
299 if (!vendor_directory) {
300 directories[0] = root_directory;
301 } else {
302 // Legacy layout of configuration ROM described in Annex 1 of
303 // 'Configuration ROM for AV/C Devices 1.0 (December 12, 2000, 1394 Trading
304 // Association, TA Document 1999027)'.
305 directories[0] = vendor_directory;
306 directories[1] = root_directory;
307 }
308 }
309
310 for (i = 0; i < ARRAY_SIZE(directories) && !!directories[i]; ++i) {
311 int key, val;
312
313 fw_csr_iterator_init(&ci, directories[i]);
314 while (fw_csr_iterator_next(&ci, &key, &val)) {
315 if (attr->key == key)
316 value = val;
317 }
318 }
319
320 up_read(&fw_device_rwsem);
321
322 if (value < 0)
323 return -ENOENT;
324
325 return snprintf(buf, buf ? PAGE_SIZE : 0, "0x%06x\n", value);
326}
327
328#define IMMEDIATE_ATTR(name, key) \
329 { __ATTR(name, S_IRUGO, show_immediate, NULL), key }
330
331static ssize_t show_text_leaf(struct device *dev,
332 struct device_attribute *dattr, char *buf)
333{
334 struct config_rom_attribute *attr =
335 container_of(dattr, struct config_rom_attribute, attr);
336 const u32 *directories[] = {NULL, NULL};
337 size_t bufsize;
338 char dummy_buf[2];
339 int i, ret = -ENOENT;
340
341 down_read(&fw_device_rwsem);
342
343 if (is_fw_unit(dev)) {
344 directories[0] = fw_unit(dev)->directory;
345 } else {
346 const u32 *root_directory = fw_device(dev)->config_rom + ROOT_DIR_OFFSET;
347 const u32 *vendor_directory = search_directory(root_directory, CSR_VENDOR);
348
349 if (!vendor_directory) {
350 directories[0] = root_directory;
351 } else {
352 // Legacy layout of configuration ROM described in Annex 1 of
353 // 'Configuration ROM for AV/C Devices 1.0 (December 12, 2000, 1394
354 // Trading Association, TA Document 1999027)'.
355 directories[0] = root_directory;
356 directories[1] = vendor_directory;
357 }
358 }
359
360 if (buf) {
361 bufsize = PAGE_SIZE - 1;
362 } else {
363 buf = dummy_buf;
364 bufsize = 1;
365 }
366
367 for (i = 0; i < ARRAY_SIZE(directories) && !!directories[i]; ++i) {
368 int result = fw_csr_string(directories[i], attr->key, buf, bufsize);
369 // Detected.
370 if (result >= 0) {
371 ret = result;
372 } else if (i == 0 && attr->key == CSR_VENDOR) {
373 // Sony DVMC-DA1 has configuration ROM such that the descriptor leaf entry
374 // in the root directory follows to the directory entry for vendor ID
375 // instead of the immediate value for vendor ID.
376 result = fw_csr_string(directories[i], CSR_DIRECTORY | attr->key, buf,
377 bufsize);
378 if (result >= 0)
379 ret = result;
380 }
381 }
382
383 if (ret >= 0) {
384 /* Strip trailing whitespace and add newline. */
385 while (ret > 0 && isspace(buf[ret - 1]))
386 ret--;
387 strcpy(buf + ret, "\n");
388 ret++;
389 }
390
391 up_read(&fw_device_rwsem);
392
393 return ret;
394}
395
396#define TEXT_LEAF_ATTR(name, key) \
397 { __ATTR(name, S_IRUGO, show_text_leaf, NULL), key }
398
399static struct config_rom_attribute config_rom_attributes[] = {
400 IMMEDIATE_ATTR(vendor, CSR_VENDOR),
401 IMMEDIATE_ATTR(hardware_version, CSR_HARDWARE_VERSION),
402 IMMEDIATE_ATTR(specifier_id, CSR_SPECIFIER_ID),
403 IMMEDIATE_ATTR(version, CSR_VERSION),
404 IMMEDIATE_ATTR(model, CSR_MODEL),
405 TEXT_LEAF_ATTR(vendor_name, CSR_VENDOR),
406 TEXT_LEAF_ATTR(model_name, CSR_MODEL),
407 TEXT_LEAF_ATTR(hardware_version_name, CSR_HARDWARE_VERSION),
408};
409
410static void init_fw_attribute_group(struct device *dev,
411 struct device_attribute *attrs,
412 struct fw_attribute_group *group)
413{
414 struct device_attribute *attr;
415 int i, j;
416
417 for (j = 0; attrs[j].attr.name != NULL; j++)
418 group->attrs[j] = &attrs[j].attr;
419
420 for (i = 0; i < ARRAY_SIZE(config_rom_attributes); i++) {
421 attr = &config_rom_attributes[i].attr;
422 if (attr->show(dev, attr, NULL) < 0)
423 continue;
424 group->attrs[j++] = &attr->attr;
425 }
426
427 group->attrs[j] = NULL;
428 group->groups[0] = &group->group;
429 group->groups[1] = NULL;
430 group->group.attrs = group->attrs;
431 dev->groups = (const struct attribute_group **) group->groups;
432}
433
434static ssize_t modalias_show(struct device *dev,
435 struct device_attribute *attr, char *buf)
436{
437 struct fw_unit *unit = fw_unit(dev);
438 int length;
439
440 length = get_modalias(unit, buf, PAGE_SIZE);
441 strcpy(buf + length, "\n");
442
443 return length + 1;
444}
445
446static ssize_t rom_index_show(struct device *dev,
447 struct device_attribute *attr, char *buf)
448{
449 struct fw_device *device = fw_device(dev->parent);
450 struct fw_unit *unit = fw_unit(dev);
451
452 return sysfs_emit(buf, "%td\n", unit->directory - device->config_rom);
453}
454
455static struct device_attribute fw_unit_attributes[] = {
456 __ATTR_RO(modalias),
457 __ATTR_RO(rom_index),
458 __ATTR_NULL,
459};
460
461static ssize_t config_rom_show(struct device *dev,
462 struct device_attribute *attr, char *buf)
463{
464 struct fw_device *device = fw_device(dev);
465 size_t length;
466
467 down_read(&fw_device_rwsem);
468 length = device->config_rom_length * 4;
469 memcpy(buf, device->config_rom, length);
470 up_read(&fw_device_rwsem);
471
472 return length;
473}
474
475static ssize_t guid_show(struct device *dev,
476 struct device_attribute *attr, char *buf)
477{
478 struct fw_device *device = fw_device(dev);
479 int ret;
480
481 down_read(&fw_device_rwsem);
482 ret = sysfs_emit(buf, "0x%08x%08x\n", device->config_rom[3], device->config_rom[4]);
483 up_read(&fw_device_rwsem);
484
485 return ret;
486}
487
488static ssize_t is_local_show(struct device *dev,
489 struct device_attribute *attr, char *buf)
490{
491 struct fw_device *device = fw_device(dev);
492
493 return sprintf(buf, "%u\n", device->is_local);
494}
495
496static int units_sprintf(char *buf, const u32 *directory)
497{
498 struct fw_csr_iterator ci;
499 int key, value;
500 int specifier_id = 0;
501 int version = 0;
502
503 fw_csr_iterator_init(&ci, directory);
504 while (fw_csr_iterator_next(&ci, &key, &value)) {
505 switch (key) {
506 case CSR_SPECIFIER_ID:
507 specifier_id = value;
508 break;
509 case CSR_VERSION:
510 version = value;
511 break;
512 }
513 }
514
515 return sprintf(buf, "0x%06x:0x%06x ", specifier_id, version);
516}
517
518static ssize_t units_show(struct device *dev,
519 struct device_attribute *attr, char *buf)
520{
521 struct fw_device *device = fw_device(dev);
522 struct fw_csr_iterator ci;
523 int key, value, i = 0;
524
525 down_read(&fw_device_rwsem);
526 fw_csr_iterator_init(&ci, &device->config_rom[ROOT_DIR_OFFSET]);
527 while (fw_csr_iterator_next(&ci, &key, &value)) {
528 if (key != (CSR_UNIT | CSR_DIRECTORY))
529 continue;
530 i += units_sprintf(&buf[i], ci.p + value - 1);
531 if (i >= PAGE_SIZE - (8 + 1 + 8 + 1))
532 break;
533 }
534 up_read(&fw_device_rwsem);
535
536 if (i)
537 buf[i - 1] = '\n';
538
539 return i;
540}
541
542static struct device_attribute fw_device_attributes[] = {
543 __ATTR_RO(config_rom),
544 __ATTR_RO(guid),
545 __ATTR_RO(is_local),
546 __ATTR_RO(units),
547 __ATTR_NULL,
548};
549
550static int read_rom(struct fw_device *device,
551 int generation, int index, u32 *data)
552{
553 u64 offset = (CSR_REGISTER_BASE | CSR_CONFIG_ROM) + index * 4;
554 int i, rcode;
555
556 /* device->node_id, accessed below, must not be older than generation */
557 smp_rmb();
558
559 for (i = 10; i < 100; i += 10) {
560 rcode = fw_run_transaction(device->card,
561 TCODE_READ_QUADLET_REQUEST, device->node_id,
562 generation, device->max_speed, offset, data, 4);
563 if (rcode != RCODE_BUSY)
564 break;
565 msleep(i);
566 }
567 be32_to_cpus(data);
568
569 return rcode;
570}
571
572#define MAX_CONFIG_ROM_SIZE 256
573
574/*
575 * Read the bus info block, perform a speed probe, and read all of the rest of
576 * the config ROM. We do all this with a cached bus generation. If the bus
577 * generation changes under us, read_config_rom will fail and get retried.
578 * It's better to start all over in this case because the node from which we
579 * are reading the ROM may have changed the ROM during the reset.
580 * Returns either a result code or a negative error code.
581 */
582static int read_config_rom(struct fw_device *device, int generation)
583{
584 struct fw_card *card = device->card;
585 const u32 *old_rom, *new_rom;
586 u32 *rom, *stack;
587 u32 sp, key;
588 int i, end, length, ret;
589
590 rom = kmalloc(sizeof(*rom) * MAX_CONFIG_ROM_SIZE +
591 sizeof(*stack) * MAX_CONFIG_ROM_SIZE, GFP_KERNEL);
592 if (rom == NULL)
593 return -ENOMEM;
594
595 stack = &rom[MAX_CONFIG_ROM_SIZE];
596 memset(rom, 0, sizeof(*rom) * MAX_CONFIG_ROM_SIZE);
597
598 device->max_speed = SCODE_100;
599
600 /* First read the bus info block. */
601 for (i = 0; i < 5; i++) {
602 ret = read_rom(device, generation, i, &rom[i]);
603 if (ret != RCODE_COMPLETE)
604 goto out;
605 /*
606 * As per IEEE1212 7.2, during initialization, devices can
607 * reply with a 0 for the first quadlet of the config
608 * rom to indicate that they are booting (for example,
609 * if the firmware is on the disk of a external
610 * harddisk). In that case we just fail, and the
611 * retry mechanism will try again later.
612 */
613 if (i == 0 && rom[i] == 0) {
614 ret = RCODE_BUSY;
615 goto out;
616 }
617 }
618
619 device->max_speed = device->node->max_speed;
620
621 /*
622 * Determine the speed of
623 * - devices with link speed less than PHY speed,
624 * - devices with 1394b PHY (unless only connected to 1394a PHYs),
625 * - all devices if there are 1394b repeaters.
626 * Note, we cannot use the bus info block's link_spd as starting point
627 * because some buggy firmwares set it lower than necessary and because
628 * 1394-1995 nodes do not have the field.
629 */
630 if ((rom[2] & 0x7) < device->max_speed ||
631 device->max_speed == SCODE_BETA ||
632 card->beta_repeaters_present) {
633 u32 dummy;
634
635 /* for S1600 and S3200 */
636 if (device->max_speed == SCODE_BETA)
637 device->max_speed = card->link_speed;
638
639 while (device->max_speed > SCODE_100) {
640 if (read_rom(device, generation, 0, &dummy) ==
641 RCODE_COMPLETE)
642 break;
643 device->max_speed--;
644 }
645 }
646
647 /*
648 * Now parse the config rom. The config rom is a recursive
649 * directory structure so we parse it using a stack of
650 * references to the blocks that make up the structure. We
651 * push a reference to the root directory on the stack to
652 * start things off.
653 */
654 length = i;
655 sp = 0;
656 stack[sp++] = 0xc0000005;
657 while (sp > 0) {
658 /*
659 * Pop the next block reference of the stack. The
660 * lower 24 bits is the offset into the config rom,
661 * the upper 8 bits are the type of the reference the
662 * block.
663 */
664 key = stack[--sp];
665 i = key & 0xffffff;
666 if (WARN_ON(i >= MAX_CONFIG_ROM_SIZE)) {
667 ret = -ENXIO;
668 goto out;
669 }
670
671 /* Read header quadlet for the block to get the length. */
672 ret = read_rom(device, generation, i, &rom[i]);
673 if (ret != RCODE_COMPLETE)
674 goto out;
675 end = i + (rom[i] >> 16) + 1;
676 if (end > MAX_CONFIG_ROM_SIZE) {
677 /*
678 * This block extends outside the config ROM which is
679 * a firmware bug. Ignore this whole block, i.e.
680 * simply set a fake block length of 0.
681 */
682 fw_err(card, "skipped invalid ROM block %x at %llx\n",
683 rom[i],
684 i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
685 rom[i] = 0;
686 end = i;
687 }
688 i++;
689
690 /*
691 * Now read in the block. If this is a directory
692 * block, check the entries as we read them to see if
693 * it references another block, and push it in that case.
694 */
695 for (; i < end; i++) {
696 ret = read_rom(device, generation, i, &rom[i]);
697 if (ret != RCODE_COMPLETE)
698 goto out;
699
700 if ((key >> 30) != 3 || (rom[i] >> 30) < 2)
701 continue;
702 /*
703 * Offset points outside the ROM. May be a firmware
704 * bug or an Extended ROM entry (IEEE 1212-2001 clause
705 * 7.7.18). Simply overwrite this pointer here by a
706 * fake immediate entry so that later iterators over
707 * the ROM don't have to check offsets all the time.
708 */
709 if (i + (rom[i] & 0xffffff) >= MAX_CONFIG_ROM_SIZE) {
710 fw_err(card,
711 "skipped unsupported ROM entry %x at %llx\n",
712 rom[i],
713 i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
714 rom[i] = 0;
715 continue;
716 }
717 stack[sp++] = i + rom[i];
718 }
719 if (length < i)
720 length = i;
721 }
722
723 old_rom = device->config_rom;
724 new_rom = kmemdup(rom, length * 4, GFP_KERNEL);
725 if (new_rom == NULL) {
726 ret = -ENOMEM;
727 goto out;
728 }
729
730 down_write(&fw_device_rwsem);
731 device->config_rom = new_rom;
732 device->config_rom_length = length;
733 up_write(&fw_device_rwsem);
734
735 kfree(old_rom);
736 ret = RCODE_COMPLETE;
737 device->max_rec = rom[2] >> 12 & 0xf;
738 device->cmc = rom[2] >> 30 & 1;
739 device->irmc = rom[2] >> 31 & 1;
740 out:
741 kfree(rom);
742
743 return ret;
744}
745
746static void fw_unit_release(struct device *dev)
747{
748 struct fw_unit *unit = fw_unit(dev);
749
750 fw_device_put(fw_parent_device(unit));
751 kfree(unit);
752}
753
754static struct device_type fw_unit_type = {
755 .uevent = fw_unit_uevent,
756 .release = fw_unit_release,
757};
758
759static bool is_fw_unit(const struct device *dev)
760{
761 return dev->type == &fw_unit_type;
762}
763
764static void create_units(struct fw_device *device)
765{
766 struct fw_csr_iterator ci;
767 struct fw_unit *unit;
768 int key, value, i;
769
770 i = 0;
771 fw_csr_iterator_init(&ci, &device->config_rom[ROOT_DIR_OFFSET]);
772 while (fw_csr_iterator_next(&ci, &key, &value)) {
773 if (key != (CSR_UNIT | CSR_DIRECTORY))
774 continue;
775
776 /*
777 * Get the address of the unit directory and try to
778 * match the drivers id_tables against it.
779 */
780 unit = kzalloc(sizeof(*unit), GFP_KERNEL);
781 if (unit == NULL)
782 continue;
783
784 unit->directory = ci.p + value - 1;
785 unit->device.bus = &fw_bus_type;
786 unit->device.type = &fw_unit_type;
787 unit->device.parent = &device->device;
788 dev_set_name(&unit->device, "%s.%d", dev_name(&device->device), i++);
789
790 BUILD_BUG_ON(ARRAY_SIZE(unit->attribute_group.attrs) <
791 ARRAY_SIZE(fw_unit_attributes) +
792 ARRAY_SIZE(config_rom_attributes));
793 init_fw_attribute_group(&unit->device,
794 fw_unit_attributes,
795 &unit->attribute_group);
796
797 fw_device_get(device);
798 if (device_register(&unit->device) < 0) {
799 put_device(&unit->device);
800 continue;
801 }
802 }
803}
804
805static int shutdown_unit(struct device *device, void *data)
806{
807 device_unregister(device);
808
809 return 0;
810}
811
812/*
813 * fw_device_rwsem acts as dual purpose mutex:
814 * - serializes accesses to fw_device_idr,
815 * - serializes accesses to fw_device.config_rom/.config_rom_length and
816 * fw_unit.directory, unless those accesses happen at safe occasions
817 */
818DECLARE_RWSEM(fw_device_rwsem);
819
820DEFINE_IDR(fw_device_idr);
821int fw_cdev_major;
822
823struct fw_device *fw_device_get_by_devt(dev_t devt)
824{
825 struct fw_device *device;
826
827 down_read(&fw_device_rwsem);
828 device = idr_find(&fw_device_idr, MINOR(devt));
829 if (device)
830 fw_device_get(device);
831 up_read(&fw_device_rwsem);
832
833 return device;
834}
835
836struct workqueue_struct *fw_workqueue;
837EXPORT_SYMBOL(fw_workqueue);
838
839static void fw_schedule_device_work(struct fw_device *device,
840 unsigned long delay)
841{
842 queue_delayed_work(fw_workqueue, &device->work, delay);
843}
844
845/*
846 * These defines control the retry behavior for reading the config
847 * rom. It shouldn't be necessary to tweak these; if the device
848 * doesn't respond to a config rom read within 10 seconds, it's not
849 * going to respond at all. As for the initial delay, a lot of
850 * devices will be able to respond within half a second after bus
851 * reset. On the other hand, it's not really worth being more
852 * aggressive than that, since it scales pretty well; if 10 devices
853 * are plugged in, they're all getting read within one second.
854 */
855
856#define MAX_RETRIES 10
857#define RETRY_DELAY (3 * HZ)
858#define INITIAL_DELAY (HZ / 2)
859#define SHUTDOWN_DELAY (2 * HZ)
860
861static void fw_device_shutdown(struct work_struct *work)
862{
863 struct fw_device *device =
864 container_of(work, struct fw_device, work.work);
865 int minor = MINOR(device->device.devt);
866
867 if (time_before64(get_jiffies_64(),
868 device->card->reset_jiffies + SHUTDOWN_DELAY)
869 && !list_empty(&device->card->link)) {
870 fw_schedule_device_work(device, SHUTDOWN_DELAY);
871 return;
872 }
873
874 if (atomic_cmpxchg(&device->state,
875 FW_DEVICE_GONE,
876 FW_DEVICE_SHUTDOWN) != FW_DEVICE_GONE)
877 return;
878
879 fw_device_cdev_remove(device);
880 device_for_each_child(&device->device, NULL, shutdown_unit);
881 device_unregister(&device->device);
882
883 down_write(&fw_device_rwsem);
884 idr_remove(&fw_device_idr, minor);
885 up_write(&fw_device_rwsem);
886
887 fw_device_put(device);
888}
889
890static void fw_device_release(struct device *dev)
891{
892 struct fw_device *device = fw_device(dev);
893 struct fw_card *card = device->card;
894 unsigned long flags;
895
896 /*
897 * Take the card lock so we don't set this to NULL while a
898 * FW_NODE_UPDATED callback is being handled or while the
899 * bus manager work looks at this node.
900 */
901 spin_lock_irqsave(&card->lock, flags);
902 device->node->data = NULL;
903 spin_unlock_irqrestore(&card->lock, flags);
904
905 fw_node_put(device->node);
906 kfree(device->config_rom);
907 kfree(device);
908 fw_card_put(card);
909}
910
911static struct device_type fw_device_type = {
912 .release = fw_device_release,
913};
914
915static bool is_fw_device(const struct device *dev)
916{
917 return dev->type == &fw_device_type;
918}
919
920static int update_unit(struct device *dev, void *data)
921{
922 struct fw_unit *unit = fw_unit(dev);
923 struct fw_driver *driver = (struct fw_driver *)dev->driver;
924
925 if (is_fw_unit(dev) && driver != NULL && driver->update != NULL) {
926 device_lock(dev);
927 driver->update(unit);
928 device_unlock(dev);
929 }
930
931 return 0;
932}
933
934static void fw_device_update(struct work_struct *work)
935{
936 struct fw_device *device =
937 container_of(work, struct fw_device, work.work);
938
939 fw_device_cdev_update(device);
940 device_for_each_child(&device->device, NULL, update_unit);
941}
942
943/*
944 * If a device was pending for deletion because its node went away but its
945 * bus info block and root directory header matches that of a newly discovered
946 * device, revive the existing fw_device.
947 * The newly allocated fw_device becomes obsolete instead.
948 */
949static int lookup_existing_device(struct device *dev, void *data)
950{
951 struct fw_device *old = fw_device(dev);
952 struct fw_device *new = data;
953 struct fw_card *card = new->card;
954 int match = 0;
955
956 if (!is_fw_device(dev))
957 return 0;
958
959 down_read(&fw_device_rwsem); /* serialize config_rom access */
960 spin_lock_irq(&card->lock); /* serialize node access */
961
962 if (memcmp(old->config_rom, new->config_rom, 6 * 4) == 0 &&
963 atomic_cmpxchg(&old->state,
964 FW_DEVICE_GONE,
965 FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
966 struct fw_node *current_node = new->node;
967 struct fw_node *obsolete_node = old->node;
968
969 new->node = obsolete_node;
970 new->node->data = new;
971 old->node = current_node;
972 old->node->data = old;
973
974 old->max_speed = new->max_speed;
975 old->node_id = current_node->node_id;
976 smp_wmb(); /* update node_id before generation */
977 old->generation = card->generation;
978 old->config_rom_retries = 0;
979 fw_notice(card, "rediscovered device %s\n", dev_name(dev));
980
981 old->workfn = fw_device_update;
982 fw_schedule_device_work(old, 0);
983
984 if (current_node == card->root_node)
985 fw_schedule_bm_work(card, 0);
986
987 match = 1;
988 }
989
990 spin_unlock_irq(&card->lock);
991 up_read(&fw_device_rwsem);
992
993 return match;
994}
995
996enum { BC_UNKNOWN = 0, BC_UNIMPLEMENTED, BC_IMPLEMENTED, };
997
998static void set_broadcast_channel(struct fw_device *device, int generation)
999{
1000 struct fw_card *card = device->card;
1001 __be32 data;
1002 int rcode;
1003
1004 if (!card->broadcast_channel_allocated)
1005 return;
1006
1007 /*
1008 * The Broadcast_Channel Valid bit is required by nodes which want to
1009 * transmit on this channel. Such transmissions are practically
1010 * exclusive to IP over 1394 (RFC 2734). IP capable nodes are required
1011 * to be IRM capable and have a max_rec of 8 or more. We use this fact
1012 * to narrow down to which nodes we send Broadcast_Channel updates.
1013 */
1014 if (!device->irmc || device->max_rec < 8)
1015 return;
1016
1017 /*
1018 * Some 1394-1995 nodes crash if this 1394a-2000 register is written.
1019 * Perform a read test first.
1020 */
1021 if (device->bc_implemented == BC_UNKNOWN) {
1022 rcode = fw_run_transaction(card, TCODE_READ_QUADLET_REQUEST,
1023 device->node_id, generation, device->max_speed,
1024 CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
1025 &data, 4);
1026 switch (rcode) {
1027 case RCODE_COMPLETE:
1028 if (data & cpu_to_be32(1 << 31)) {
1029 device->bc_implemented = BC_IMPLEMENTED;
1030 break;
1031 }
1032 fallthrough; /* to case address error */
1033 case RCODE_ADDRESS_ERROR:
1034 device->bc_implemented = BC_UNIMPLEMENTED;
1035 }
1036 }
1037
1038 if (device->bc_implemented == BC_IMPLEMENTED) {
1039 data = cpu_to_be32(BROADCAST_CHANNEL_INITIAL |
1040 BROADCAST_CHANNEL_VALID);
1041 fw_run_transaction(card, TCODE_WRITE_QUADLET_REQUEST,
1042 device->node_id, generation, device->max_speed,
1043 CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
1044 &data, 4);
1045 }
1046}
1047
1048int fw_device_set_broadcast_channel(struct device *dev, void *gen)
1049{
1050 if (is_fw_device(dev))
1051 set_broadcast_channel(fw_device(dev), (long)gen);
1052
1053 return 0;
1054}
1055
1056static void fw_device_init(struct work_struct *work)
1057{
1058 struct fw_device *device =
1059 container_of(work, struct fw_device, work.work);
1060 struct fw_card *card = device->card;
1061 struct device *revived_dev;
1062 int minor, ret;
1063
1064 /*
1065 * All failure paths here set node->data to NULL, so that we
1066 * don't try to do device_for_each_child() on a kfree()'d
1067 * device.
1068 */
1069
1070 ret = read_config_rom(device, device->generation);
1071 if (ret != RCODE_COMPLETE) {
1072 if (device->config_rom_retries < MAX_RETRIES &&
1073 atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
1074 device->config_rom_retries++;
1075 fw_schedule_device_work(device, RETRY_DELAY);
1076 } else {
1077 if (device->node->link_on)
1078 fw_notice(card, "giving up on node %x: reading config rom failed: %s\n",
1079 device->node_id,
1080 fw_rcode_string(ret));
1081 if (device->node == card->root_node)
1082 fw_schedule_bm_work(card, 0);
1083 fw_device_release(&device->device);
1084 }
1085 return;
1086 }
1087
1088 revived_dev = device_find_child(card->device,
1089 device, lookup_existing_device);
1090 if (revived_dev) {
1091 put_device(revived_dev);
1092 fw_device_release(&device->device);
1093
1094 return;
1095 }
1096
1097 device_initialize(&device->device);
1098
1099 fw_device_get(device);
1100 down_write(&fw_device_rwsem);
1101 minor = idr_alloc(&fw_device_idr, device, 0, 1 << MINORBITS,
1102 GFP_KERNEL);
1103 up_write(&fw_device_rwsem);
1104
1105 if (minor < 0)
1106 goto error;
1107
1108 device->device.bus = &fw_bus_type;
1109 device->device.type = &fw_device_type;
1110 device->device.parent = card->device;
1111 device->device.devt = MKDEV(fw_cdev_major, minor);
1112 dev_set_name(&device->device, "fw%d", minor);
1113
1114 BUILD_BUG_ON(ARRAY_SIZE(device->attribute_group.attrs) <
1115 ARRAY_SIZE(fw_device_attributes) +
1116 ARRAY_SIZE(config_rom_attributes));
1117 init_fw_attribute_group(&device->device,
1118 fw_device_attributes,
1119 &device->attribute_group);
1120
1121 if (device_add(&device->device)) {
1122 fw_err(card, "failed to add device\n");
1123 goto error_with_cdev;
1124 }
1125
1126 create_units(device);
1127
1128 /*
1129 * Transition the device to running state. If it got pulled
1130 * out from under us while we did the initialization work, we
1131 * have to shut down the device again here. Normally, though,
1132 * fw_node_event will be responsible for shutting it down when
1133 * necessary. We have to use the atomic cmpxchg here to avoid
1134 * racing with the FW_NODE_DESTROYED case in
1135 * fw_node_event().
1136 */
1137 if (atomic_cmpxchg(&device->state,
1138 FW_DEVICE_INITIALIZING,
1139 FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
1140 device->workfn = fw_device_shutdown;
1141 fw_schedule_device_work(device, SHUTDOWN_DELAY);
1142 } else {
1143 fw_notice(card, "created device %s: GUID %08x%08x, S%d00\n",
1144 dev_name(&device->device),
1145 device->config_rom[3], device->config_rom[4],
1146 1 << device->max_speed);
1147 device->config_rom_retries = 0;
1148
1149 set_broadcast_channel(device, device->generation);
1150
1151 add_device_randomness(&device->config_rom[3], 8);
1152 }
1153
1154 /*
1155 * Reschedule the IRM work if we just finished reading the
1156 * root node config rom. If this races with a bus reset we
1157 * just end up running the IRM work a couple of extra times -
1158 * pretty harmless.
1159 */
1160 if (device->node == card->root_node)
1161 fw_schedule_bm_work(card, 0);
1162
1163 return;
1164
1165 error_with_cdev:
1166 down_write(&fw_device_rwsem);
1167 idr_remove(&fw_device_idr, minor);
1168 up_write(&fw_device_rwsem);
1169 error:
1170 fw_device_put(device); /* fw_device_idr's reference */
1171
1172 put_device(&device->device); /* our reference */
1173}
1174
1175/* Reread and compare bus info block and header of root directory */
1176static int reread_config_rom(struct fw_device *device, int generation,
1177 bool *changed)
1178{
1179 u32 q;
1180 int i, rcode;
1181
1182 for (i = 0; i < 6; i++) {
1183 rcode = read_rom(device, generation, i, &q);
1184 if (rcode != RCODE_COMPLETE)
1185 return rcode;
1186
1187 if (i == 0 && q == 0)
1188 /* inaccessible (see read_config_rom); retry later */
1189 return RCODE_BUSY;
1190
1191 if (q != device->config_rom[i]) {
1192 *changed = true;
1193 return RCODE_COMPLETE;
1194 }
1195 }
1196
1197 *changed = false;
1198 return RCODE_COMPLETE;
1199}
1200
1201static void fw_device_refresh(struct work_struct *work)
1202{
1203 struct fw_device *device =
1204 container_of(work, struct fw_device, work.work);
1205 struct fw_card *card = device->card;
1206 int ret, node_id = device->node_id;
1207 bool changed;
1208
1209 ret = reread_config_rom(device, device->generation, &changed);
1210 if (ret != RCODE_COMPLETE)
1211 goto failed_config_rom;
1212
1213 if (!changed) {
1214 if (atomic_cmpxchg(&device->state,
1215 FW_DEVICE_INITIALIZING,
1216 FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
1217 goto gone;
1218
1219 fw_device_update(work);
1220 device->config_rom_retries = 0;
1221 goto out;
1222 }
1223
1224 /*
1225 * Something changed. We keep things simple and don't investigate
1226 * further. We just destroy all previous units and create new ones.
1227 */
1228 device_for_each_child(&device->device, NULL, shutdown_unit);
1229
1230 ret = read_config_rom(device, device->generation);
1231 if (ret != RCODE_COMPLETE)
1232 goto failed_config_rom;
1233
1234 fw_device_cdev_update(device);
1235 create_units(device);
1236
1237 /* Userspace may want to re-read attributes. */
1238 kobject_uevent(&device->device.kobj, KOBJ_CHANGE);
1239
1240 if (atomic_cmpxchg(&device->state,
1241 FW_DEVICE_INITIALIZING,
1242 FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
1243 goto gone;
1244
1245 fw_notice(card, "refreshed device %s\n", dev_name(&device->device));
1246 device->config_rom_retries = 0;
1247 goto out;
1248
1249 failed_config_rom:
1250 if (device->config_rom_retries < MAX_RETRIES &&
1251 atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
1252 device->config_rom_retries++;
1253 fw_schedule_device_work(device, RETRY_DELAY);
1254 return;
1255 }
1256
1257 fw_notice(card, "giving up on refresh of device %s: %s\n",
1258 dev_name(&device->device), fw_rcode_string(ret));
1259 gone:
1260 atomic_set(&device->state, FW_DEVICE_GONE);
1261 device->workfn = fw_device_shutdown;
1262 fw_schedule_device_work(device, SHUTDOWN_DELAY);
1263 out:
1264 if (node_id == card->root_node->node_id)
1265 fw_schedule_bm_work(card, 0);
1266}
1267
1268static void fw_device_workfn(struct work_struct *work)
1269{
1270 struct fw_device *device = container_of(to_delayed_work(work),
1271 struct fw_device, work);
1272 device->workfn(work);
1273}
1274
1275void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
1276{
1277 struct fw_device *device;
1278
1279 switch (event) {
1280 case FW_NODE_CREATED:
1281 /*
1282 * Attempt to scan the node, regardless whether its self ID has
1283 * the L (link active) flag set or not. Some broken devices
1284 * send L=0 but have an up-and-running link; others send L=1
1285 * without actually having a link.
1286 */
1287 create:
1288 device = kzalloc(sizeof(*device), GFP_ATOMIC);
1289 if (device == NULL)
1290 break;
1291
1292 /*
1293 * Do minimal initialization of the device here, the
1294 * rest will happen in fw_device_init().
1295 *
1296 * Attention: A lot of things, even fw_device_get(),
1297 * cannot be done before fw_device_init() finished!
1298 * You can basically just check device->state and
1299 * schedule work until then, but only while holding
1300 * card->lock.
1301 */
1302 atomic_set(&device->state, FW_DEVICE_INITIALIZING);
1303 device->card = fw_card_get(card);
1304 device->node = fw_node_get(node);
1305 device->node_id = node->node_id;
1306 device->generation = card->generation;
1307 device->is_local = node == card->local_node;
1308 mutex_init(&device->client_list_mutex);
1309 INIT_LIST_HEAD(&device->client_list);
1310
1311 /*
1312 * Set the node data to point back to this device so
1313 * FW_NODE_UPDATED callbacks can update the node_id
1314 * and generation for the device.
1315 */
1316 node->data = device;
1317
1318 /*
1319 * Many devices are slow to respond after bus resets,
1320 * especially if they are bus powered and go through
1321 * power-up after getting plugged in. We schedule the
1322 * first config rom scan half a second after bus reset.
1323 */
1324 device->workfn = fw_device_init;
1325 INIT_DELAYED_WORK(&device->work, fw_device_workfn);
1326 fw_schedule_device_work(device, INITIAL_DELAY);
1327 break;
1328
1329 case FW_NODE_INITIATED_RESET:
1330 case FW_NODE_LINK_ON:
1331 device = node->data;
1332 if (device == NULL)
1333 goto create;
1334
1335 device->node_id = node->node_id;
1336 smp_wmb(); /* update node_id before generation */
1337 device->generation = card->generation;
1338 if (atomic_cmpxchg(&device->state,
1339 FW_DEVICE_RUNNING,
1340 FW_DEVICE_INITIALIZING) == FW_DEVICE_RUNNING) {
1341 device->workfn = fw_device_refresh;
1342 fw_schedule_device_work(device,
1343 device->is_local ? 0 : INITIAL_DELAY);
1344 }
1345 break;
1346
1347 case FW_NODE_UPDATED:
1348 device = node->data;
1349 if (device == NULL)
1350 break;
1351
1352 device->node_id = node->node_id;
1353 smp_wmb(); /* update node_id before generation */
1354 device->generation = card->generation;
1355 if (atomic_read(&device->state) == FW_DEVICE_RUNNING) {
1356 device->workfn = fw_device_update;
1357 fw_schedule_device_work(device, 0);
1358 }
1359 break;
1360
1361 case FW_NODE_DESTROYED:
1362 case FW_NODE_LINK_OFF:
1363 if (!node->data)
1364 break;
1365
1366 /*
1367 * Destroy the device associated with the node. There
1368 * are two cases here: either the device is fully
1369 * initialized (FW_DEVICE_RUNNING) or we're in the
1370 * process of reading its config rom
1371 * (FW_DEVICE_INITIALIZING). If it is fully
1372 * initialized we can reuse device->work to schedule a
1373 * full fw_device_shutdown(). If not, there's work
1374 * scheduled to read it's config rom, and we just put
1375 * the device in shutdown state to have that code fail
1376 * to create the device.
1377 */
1378 device = node->data;
1379 if (atomic_xchg(&device->state,
1380 FW_DEVICE_GONE) == FW_DEVICE_RUNNING) {
1381 device->workfn = fw_device_shutdown;
1382 fw_schedule_device_work(device,
1383 list_empty(&card->link) ? 0 : SHUTDOWN_DELAY);
1384 }
1385 break;
1386 }
1387}
1388
1389#ifdef CONFIG_FIREWIRE_KUNIT_DEVICE_ATTRIBUTE_TEST
1390#include "device-attribute-test.c"
1391#endif
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}