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1/*
2 * Device probing and sysfs code.
3 *
4 * Copyright (C) 2005-2006 Kristian Hoegsberg <krh@bitplanet.net>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software Foundation,
18 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 */
20
21#include <linux/bug.h>
22#include <linux/ctype.h>
23#include <linux/delay.h>
24#include <linux/device.h>
25#include <linux/errno.h>
26#include <linux/firewire.h>
27#include <linux/firewire-constants.h>
28#include <linux/idr.h>
29#include <linux/jiffies.h>
30#include <linux/kobject.h>
31#include <linux/list.h>
32#include <linux/mod_devicetable.h>
33#include <linux/module.h>
34#include <linux/mutex.h>
35#include <linux/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}
1/*
2 * Device probing and sysfs code.
3 *
4 * Copyright (C) 2005-2006 Kristian Hoegsberg <krh@bitplanet.net>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software Foundation,
18 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 */
20
21#include <linux/bug.h>
22#include <linux/ctype.h>
23#include <linux/delay.h>
24#include <linux/device.h>
25#include <linux/errno.h>
26#include <linux/firewire.h>
27#include <linux/firewire-constants.h>
28#include <linux/idr.h>
29#include <linux/jiffies.h>
30#include <linux/kobject.h>
31#include <linux/list.h>
32#include <linux/mod_devicetable.h>
33#include <linux/module.h>
34#include <linux/mutex.h>
35#include <linux/random.h>
36#include <linux/rwsem.h>
37#include <linux/slab.h>
38#include <linux/spinlock.h>
39#include <linux/string.h>
40#include <linux/workqueue.h>
41
42#include <linux/atomic.h>
43#include <asm/byteorder.h>
44
45#include "core.h"
46
47void fw_csr_iterator_init(struct fw_csr_iterator *ci, const u32 *p)
48{
49 ci->p = p + 1;
50 ci->end = ci->p + (p[0] >> 16);
51}
52EXPORT_SYMBOL(fw_csr_iterator_init);
53
54int fw_csr_iterator_next(struct fw_csr_iterator *ci, int *key, int *value)
55{
56 *key = *ci->p >> 24;
57 *value = *ci->p & 0xffffff;
58
59 return ci->p++ < ci->end;
60}
61EXPORT_SYMBOL(fw_csr_iterator_next);
62
63static const u32 *search_leaf(const u32 *directory, int search_key)
64{
65 struct fw_csr_iterator ci;
66 int last_key = 0, key, value;
67
68 fw_csr_iterator_init(&ci, directory);
69 while (fw_csr_iterator_next(&ci, &key, &value)) {
70 if (last_key == search_key &&
71 key == (CSR_DESCRIPTOR | CSR_LEAF))
72 return ci.p - 1 + value;
73
74 last_key = key;
75 }
76
77 return NULL;
78}
79
80static int textual_leaf_to_string(const u32 *block, char *buf, size_t size)
81{
82 unsigned int quadlets, i;
83 char c;
84
85 if (!size || !buf)
86 return -EINVAL;
87
88 quadlets = min(block[0] >> 16, 256U);
89 if (quadlets < 2)
90 return -ENODATA;
91
92 if (block[1] != 0 || block[2] != 0)
93 /* unknown language/character set */
94 return -ENODATA;
95
96 block += 3;
97 quadlets -= 2;
98 for (i = 0; i < quadlets * 4 && i < size - 1; i++) {
99 c = block[i / 4] >> (24 - 8 * (i % 4));
100 if (c == '\0')
101 break;
102 buf[i] = c;
103 }
104 buf[i] = '\0';
105
106 return i;
107}
108
109/**
110 * fw_csr_string() - reads a string from the configuration ROM
111 * @directory: e.g. root directory or unit directory
112 * @key: the key of the preceding directory entry
113 * @buf: where to put the string
114 * @size: size of @buf, in bytes
115 *
116 * The string is taken from a minimal ASCII text descriptor leaf after
117 * the immediate entry with @key. The string is zero-terminated.
118 * Returns strlen(buf) or a negative error code.
119 */
120int fw_csr_string(const u32 *directory, int key, char *buf, size_t size)
121{
122 const u32 *leaf = search_leaf(directory, key);
123 if (!leaf)
124 return -ENOENT;
125
126 return textual_leaf_to_string(leaf, buf, size);
127}
128EXPORT_SYMBOL(fw_csr_string);
129
130static void get_ids(const u32 *directory, int *id)
131{
132 struct fw_csr_iterator ci;
133 int key, value;
134
135 fw_csr_iterator_init(&ci, directory);
136 while (fw_csr_iterator_next(&ci, &key, &value)) {
137 switch (key) {
138 case CSR_VENDOR: id[0] = value; break;
139 case CSR_MODEL: id[1] = value; break;
140 case CSR_SPECIFIER_ID: id[2] = value; break;
141 case CSR_VERSION: id[3] = value; break;
142 }
143 }
144}
145
146static void get_modalias_ids(struct fw_unit *unit, int *id)
147{
148 get_ids(&fw_parent_device(unit)->config_rom[5], id);
149 get_ids(unit->directory, id);
150}
151
152static bool match_ids(const struct ieee1394_device_id *id_table, int *id)
153{
154 int match = 0;
155
156 if (id[0] == id_table->vendor_id)
157 match |= IEEE1394_MATCH_VENDOR_ID;
158 if (id[1] == id_table->model_id)
159 match |= IEEE1394_MATCH_MODEL_ID;
160 if (id[2] == id_table->specifier_id)
161 match |= IEEE1394_MATCH_SPECIFIER_ID;
162 if (id[3] == id_table->version)
163 match |= IEEE1394_MATCH_VERSION;
164
165 return (match & id_table->match_flags) == id_table->match_flags;
166}
167
168static const struct ieee1394_device_id *unit_match(struct device *dev,
169 struct device_driver *drv)
170{
171 const struct ieee1394_device_id *id_table =
172 container_of(drv, struct fw_driver, driver)->id_table;
173 int id[] = {0, 0, 0, 0};
174
175 get_modalias_ids(fw_unit(dev), id);
176
177 for (; id_table->match_flags != 0; id_table++)
178 if (match_ids(id_table, id))
179 return id_table;
180
181 return NULL;
182}
183
184static bool is_fw_unit(struct device *dev);
185
186static int fw_unit_match(struct device *dev, struct device_driver *drv)
187{
188 /* We only allow binding to fw_units. */
189 return is_fw_unit(dev) && unit_match(dev, drv) != NULL;
190}
191
192static int fw_unit_probe(struct device *dev)
193{
194 struct fw_driver *driver =
195 container_of(dev->driver, struct fw_driver, driver);
196
197 return driver->probe(fw_unit(dev), unit_match(dev, dev->driver));
198}
199
200static int fw_unit_remove(struct device *dev)
201{
202 struct fw_driver *driver =
203 container_of(dev->driver, struct fw_driver, driver);
204
205 return driver->remove(fw_unit(dev)), 0;
206}
207
208static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
209{
210 int id[] = {0, 0, 0, 0};
211
212 get_modalias_ids(unit, id);
213
214 return snprintf(buffer, buffer_size,
215 "ieee1394:ven%08Xmo%08Xsp%08Xver%08X",
216 id[0], id[1], id[2], id[3]);
217}
218
219static int fw_unit_uevent(struct device *dev, struct kobj_uevent_env *env)
220{
221 struct fw_unit *unit = fw_unit(dev);
222 char modalias[64];
223
224 get_modalias(unit, modalias, sizeof(modalias));
225
226 if (add_uevent_var(env, "MODALIAS=%s", modalias))
227 return -ENOMEM;
228
229 return 0;
230}
231
232struct bus_type fw_bus_type = {
233 .name = "firewire",
234 .match = fw_unit_match,
235 .probe = fw_unit_probe,
236 .remove = fw_unit_remove,
237};
238EXPORT_SYMBOL(fw_bus_type);
239
240int fw_device_enable_phys_dma(struct fw_device *device)
241{
242 int generation = device->generation;
243
244 /* device->node_id, accessed below, must not be older than generation */
245 smp_rmb();
246
247 return device->card->driver->enable_phys_dma(device->card,
248 device->node_id,
249 generation);
250}
251EXPORT_SYMBOL(fw_device_enable_phys_dma);
252
253struct config_rom_attribute {
254 struct device_attribute attr;
255 u32 key;
256};
257
258static ssize_t show_immediate(struct device *dev,
259 struct device_attribute *dattr, char *buf)
260{
261 struct config_rom_attribute *attr =
262 container_of(dattr, struct config_rom_attribute, attr);
263 struct fw_csr_iterator ci;
264 const u32 *dir;
265 int key, value, ret = -ENOENT;
266
267 down_read(&fw_device_rwsem);
268
269 if (is_fw_unit(dev))
270 dir = fw_unit(dev)->directory;
271 else
272 dir = fw_device(dev)->config_rom + 5;
273
274 fw_csr_iterator_init(&ci, dir);
275 while (fw_csr_iterator_next(&ci, &key, &value))
276 if (attr->key == key) {
277 ret = snprintf(buf, buf ? PAGE_SIZE : 0,
278 "0x%06x\n", value);
279 break;
280 }
281
282 up_read(&fw_device_rwsem);
283
284 return ret;
285}
286
287#define IMMEDIATE_ATTR(name, key) \
288 { __ATTR(name, S_IRUGO, show_immediate, NULL), key }
289
290static ssize_t show_text_leaf(struct device *dev,
291 struct device_attribute *dattr, char *buf)
292{
293 struct config_rom_attribute *attr =
294 container_of(dattr, struct config_rom_attribute, attr);
295 const u32 *dir;
296 size_t bufsize;
297 char dummy_buf[2];
298 int ret;
299
300 down_read(&fw_device_rwsem);
301
302 if (is_fw_unit(dev))
303 dir = fw_unit(dev)->directory;
304 else
305 dir = fw_device(dev)->config_rom + 5;
306
307 if (buf) {
308 bufsize = PAGE_SIZE - 1;
309 } else {
310 buf = dummy_buf;
311 bufsize = 1;
312 }
313
314 ret = fw_csr_string(dir, attr->key, buf, bufsize);
315
316 if (ret >= 0) {
317 /* Strip trailing whitespace and add newline. */
318 while (ret > 0 && isspace(buf[ret - 1]))
319 ret--;
320 strcpy(buf + ret, "\n");
321 ret++;
322 }
323
324 up_read(&fw_device_rwsem);
325
326 return ret;
327}
328
329#define TEXT_LEAF_ATTR(name, key) \
330 { __ATTR(name, S_IRUGO, show_text_leaf, NULL), key }
331
332static struct config_rom_attribute config_rom_attributes[] = {
333 IMMEDIATE_ATTR(vendor, CSR_VENDOR),
334 IMMEDIATE_ATTR(hardware_version, CSR_HARDWARE_VERSION),
335 IMMEDIATE_ATTR(specifier_id, CSR_SPECIFIER_ID),
336 IMMEDIATE_ATTR(version, CSR_VERSION),
337 IMMEDIATE_ATTR(model, CSR_MODEL),
338 TEXT_LEAF_ATTR(vendor_name, CSR_VENDOR),
339 TEXT_LEAF_ATTR(model_name, CSR_MODEL),
340 TEXT_LEAF_ATTR(hardware_version_name, CSR_HARDWARE_VERSION),
341};
342
343static void init_fw_attribute_group(struct device *dev,
344 struct device_attribute *attrs,
345 struct fw_attribute_group *group)
346{
347 struct device_attribute *attr;
348 int i, j;
349
350 for (j = 0; attrs[j].attr.name != NULL; j++)
351 group->attrs[j] = &attrs[j].attr;
352
353 for (i = 0; i < ARRAY_SIZE(config_rom_attributes); i++) {
354 attr = &config_rom_attributes[i].attr;
355 if (attr->show(dev, attr, NULL) < 0)
356 continue;
357 group->attrs[j++] = &attr->attr;
358 }
359
360 group->attrs[j] = NULL;
361 group->groups[0] = &group->group;
362 group->groups[1] = NULL;
363 group->group.attrs = group->attrs;
364 dev->groups = (const struct attribute_group **) group->groups;
365}
366
367static ssize_t modalias_show(struct device *dev,
368 struct device_attribute *attr, char *buf)
369{
370 struct fw_unit *unit = fw_unit(dev);
371 int length;
372
373 length = get_modalias(unit, buf, PAGE_SIZE);
374 strcpy(buf + length, "\n");
375
376 return length + 1;
377}
378
379static ssize_t rom_index_show(struct device *dev,
380 struct device_attribute *attr, char *buf)
381{
382 struct fw_device *device = fw_device(dev->parent);
383 struct fw_unit *unit = fw_unit(dev);
384
385 return snprintf(buf, PAGE_SIZE, "%d\n",
386 (int)(unit->directory - device->config_rom));
387}
388
389static struct device_attribute fw_unit_attributes[] = {
390 __ATTR_RO(modalias),
391 __ATTR_RO(rom_index),
392 __ATTR_NULL,
393};
394
395static ssize_t config_rom_show(struct device *dev,
396 struct device_attribute *attr, char *buf)
397{
398 struct fw_device *device = fw_device(dev);
399 size_t length;
400
401 down_read(&fw_device_rwsem);
402 length = device->config_rom_length * 4;
403 memcpy(buf, device->config_rom, length);
404 up_read(&fw_device_rwsem);
405
406 return length;
407}
408
409static ssize_t guid_show(struct device *dev,
410 struct device_attribute *attr, char *buf)
411{
412 struct fw_device *device = fw_device(dev);
413 int ret;
414
415 down_read(&fw_device_rwsem);
416 ret = snprintf(buf, PAGE_SIZE, "0x%08x%08x\n",
417 device->config_rom[3], device->config_rom[4]);
418 up_read(&fw_device_rwsem);
419
420 return ret;
421}
422
423static ssize_t is_local_show(struct device *dev,
424 struct device_attribute *attr, char *buf)
425{
426 struct fw_device *device = fw_device(dev);
427
428 return sprintf(buf, "%u\n", device->is_local);
429}
430
431static int units_sprintf(char *buf, const u32 *directory)
432{
433 struct fw_csr_iterator ci;
434 int key, value;
435 int specifier_id = 0;
436 int version = 0;
437
438 fw_csr_iterator_init(&ci, directory);
439 while (fw_csr_iterator_next(&ci, &key, &value)) {
440 switch (key) {
441 case CSR_SPECIFIER_ID:
442 specifier_id = value;
443 break;
444 case CSR_VERSION:
445 version = value;
446 break;
447 }
448 }
449
450 return sprintf(buf, "0x%06x:0x%06x ", specifier_id, version);
451}
452
453static ssize_t units_show(struct device *dev,
454 struct device_attribute *attr, char *buf)
455{
456 struct fw_device *device = fw_device(dev);
457 struct fw_csr_iterator ci;
458 int key, value, i = 0;
459
460 down_read(&fw_device_rwsem);
461 fw_csr_iterator_init(&ci, &device->config_rom[5]);
462 while (fw_csr_iterator_next(&ci, &key, &value)) {
463 if (key != (CSR_UNIT | CSR_DIRECTORY))
464 continue;
465 i += units_sprintf(&buf[i], ci.p + value - 1);
466 if (i >= PAGE_SIZE - (8 + 1 + 8 + 1))
467 break;
468 }
469 up_read(&fw_device_rwsem);
470
471 if (i)
472 buf[i - 1] = '\n';
473
474 return i;
475}
476
477static struct device_attribute fw_device_attributes[] = {
478 __ATTR_RO(config_rom),
479 __ATTR_RO(guid),
480 __ATTR_RO(is_local),
481 __ATTR_RO(units),
482 __ATTR_NULL,
483};
484
485static int read_rom(struct fw_device *device,
486 int generation, int index, u32 *data)
487{
488 u64 offset = (CSR_REGISTER_BASE | CSR_CONFIG_ROM) + index * 4;
489 int i, rcode;
490
491 /* device->node_id, accessed below, must not be older than generation */
492 smp_rmb();
493
494 for (i = 10; i < 100; i += 10) {
495 rcode = fw_run_transaction(device->card,
496 TCODE_READ_QUADLET_REQUEST, device->node_id,
497 generation, device->max_speed, offset, data, 4);
498 if (rcode != RCODE_BUSY)
499 break;
500 msleep(i);
501 }
502 be32_to_cpus(data);
503
504 return rcode;
505}
506
507#define MAX_CONFIG_ROM_SIZE 256
508
509/*
510 * Read the bus info block, perform a speed probe, and read all of the rest of
511 * the config ROM. We do all this with a cached bus generation. If the bus
512 * generation changes under us, read_config_rom will fail and get retried.
513 * It's better to start all over in this case because the node from which we
514 * are reading the ROM may have changed the ROM during the reset.
515 * Returns either a result code or a negative error code.
516 */
517static int read_config_rom(struct fw_device *device, int generation)
518{
519 struct fw_card *card = device->card;
520 const u32 *old_rom, *new_rom;
521 u32 *rom, *stack;
522 u32 sp, key;
523 int i, end, length, ret;
524
525 rom = kmalloc(sizeof(*rom) * MAX_CONFIG_ROM_SIZE +
526 sizeof(*stack) * MAX_CONFIG_ROM_SIZE, GFP_KERNEL);
527 if (rom == NULL)
528 return -ENOMEM;
529
530 stack = &rom[MAX_CONFIG_ROM_SIZE];
531 memset(rom, 0, sizeof(*rom) * MAX_CONFIG_ROM_SIZE);
532
533 device->max_speed = SCODE_100;
534
535 /* First read the bus info block. */
536 for (i = 0; i < 5; i++) {
537 ret = read_rom(device, generation, i, &rom[i]);
538 if (ret != RCODE_COMPLETE)
539 goto out;
540 /*
541 * As per IEEE1212 7.2, during initialization, devices can
542 * reply with a 0 for the first quadlet of the config
543 * rom to indicate that they are booting (for example,
544 * if the firmware is on the disk of a external
545 * harddisk). In that case we just fail, and the
546 * retry mechanism will try again later.
547 */
548 if (i == 0 && rom[i] == 0) {
549 ret = RCODE_BUSY;
550 goto out;
551 }
552 }
553
554 device->max_speed = device->node->max_speed;
555
556 /*
557 * Determine the speed of
558 * - devices with link speed less than PHY speed,
559 * - devices with 1394b PHY (unless only connected to 1394a PHYs),
560 * - all devices if there are 1394b repeaters.
561 * Note, we cannot use the bus info block's link_spd as starting point
562 * because some buggy firmwares set it lower than necessary and because
563 * 1394-1995 nodes do not have the field.
564 */
565 if ((rom[2] & 0x7) < device->max_speed ||
566 device->max_speed == SCODE_BETA ||
567 card->beta_repeaters_present) {
568 u32 dummy;
569
570 /* for S1600 and S3200 */
571 if (device->max_speed == SCODE_BETA)
572 device->max_speed = card->link_speed;
573
574 while (device->max_speed > SCODE_100) {
575 if (read_rom(device, generation, 0, &dummy) ==
576 RCODE_COMPLETE)
577 break;
578 device->max_speed--;
579 }
580 }
581
582 /*
583 * Now parse the config rom. The config rom is a recursive
584 * directory structure so we parse it using a stack of
585 * references to the blocks that make up the structure. We
586 * push a reference to the root directory on the stack to
587 * start things off.
588 */
589 length = i;
590 sp = 0;
591 stack[sp++] = 0xc0000005;
592 while (sp > 0) {
593 /*
594 * Pop the next block reference of the stack. The
595 * lower 24 bits is the offset into the config rom,
596 * the upper 8 bits are the type of the reference the
597 * block.
598 */
599 key = stack[--sp];
600 i = key & 0xffffff;
601 if (WARN_ON(i >= MAX_CONFIG_ROM_SIZE)) {
602 ret = -ENXIO;
603 goto out;
604 }
605
606 /* Read header quadlet for the block to get the length. */
607 ret = read_rom(device, generation, i, &rom[i]);
608 if (ret != RCODE_COMPLETE)
609 goto out;
610 end = i + (rom[i] >> 16) + 1;
611 if (end > MAX_CONFIG_ROM_SIZE) {
612 /*
613 * This block extends outside the config ROM which is
614 * a firmware bug. Ignore this whole block, i.e.
615 * simply set a fake block length of 0.
616 */
617 fw_err(card, "skipped invalid ROM block %x at %llx\n",
618 rom[i],
619 i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
620 rom[i] = 0;
621 end = i;
622 }
623 i++;
624
625 /*
626 * Now read in the block. If this is a directory
627 * block, check the entries as we read them to see if
628 * it references another block, and push it in that case.
629 */
630 for (; i < end; i++) {
631 ret = read_rom(device, generation, i, &rom[i]);
632 if (ret != RCODE_COMPLETE)
633 goto out;
634
635 if ((key >> 30) != 3 || (rom[i] >> 30) < 2)
636 continue;
637 /*
638 * Offset points outside the ROM. May be a firmware
639 * bug or an Extended ROM entry (IEEE 1212-2001 clause
640 * 7.7.18). Simply overwrite this pointer here by a
641 * fake immediate entry so that later iterators over
642 * the ROM don't have to check offsets all the time.
643 */
644 if (i + (rom[i] & 0xffffff) >= MAX_CONFIG_ROM_SIZE) {
645 fw_err(card,
646 "skipped unsupported ROM entry %x at %llx\n",
647 rom[i],
648 i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
649 rom[i] = 0;
650 continue;
651 }
652 stack[sp++] = i + rom[i];
653 }
654 if (length < i)
655 length = i;
656 }
657
658 old_rom = device->config_rom;
659 new_rom = kmemdup(rom, length * 4, GFP_KERNEL);
660 if (new_rom == NULL) {
661 ret = -ENOMEM;
662 goto out;
663 }
664
665 down_write(&fw_device_rwsem);
666 device->config_rom = new_rom;
667 device->config_rom_length = length;
668 up_write(&fw_device_rwsem);
669
670 kfree(old_rom);
671 ret = RCODE_COMPLETE;
672 device->max_rec = rom[2] >> 12 & 0xf;
673 device->cmc = rom[2] >> 30 & 1;
674 device->irmc = rom[2] >> 31 & 1;
675 out:
676 kfree(rom);
677
678 return ret;
679}
680
681static void fw_unit_release(struct device *dev)
682{
683 struct fw_unit *unit = fw_unit(dev);
684
685 fw_device_put(fw_parent_device(unit));
686 kfree(unit);
687}
688
689static struct device_type fw_unit_type = {
690 .uevent = fw_unit_uevent,
691 .release = fw_unit_release,
692};
693
694static bool is_fw_unit(struct device *dev)
695{
696 return dev->type == &fw_unit_type;
697}
698
699static void create_units(struct fw_device *device)
700{
701 struct fw_csr_iterator ci;
702 struct fw_unit *unit;
703 int key, value, i;
704
705 i = 0;
706 fw_csr_iterator_init(&ci, &device->config_rom[5]);
707 while (fw_csr_iterator_next(&ci, &key, &value)) {
708 if (key != (CSR_UNIT | CSR_DIRECTORY))
709 continue;
710
711 /*
712 * Get the address of the unit directory and try to
713 * match the drivers id_tables against it.
714 */
715 unit = kzalloc(sizeof(*unit), GFP_KERNEL);
716 if (unit == NULL)
717 continue;
718
719 unit->directory = ci.p + value - 1;
720 unit->device.bus = &fw_bus_type;
721 unit->device.type = &fw_unit_type;
722 unit->device.parent = &device->device;
723 dev_set_name(&unit->device, "%s.%d", dev_name(&device->device), i++);
724
725 BUILD_BUG_ON(ARRAY_SIZE(unit->attribute_group.attrs) <
726 ARRAY_SIZE(fw_unit_attributes) +
727 ARRAY_SIZE(config_rom_attributes));
728 init_fw_attribute_group(&unit->device,
729 fw_unit_attributes,
730 &unit->attribute_group);
731
732 if (device_register(&unit->device) < 0)
733 goto skip_unit;
734
735 fw_device_get(device);
736 continue;
737
738 skip_unit:
739 kfree(unit);
740 }
741}
742
743static int shutdown_unit(struct device *device, void *data)
744{
745 device_unregister(device);
746
747 return 0;
748}
749
750/*
751 * fw_device_rwsem acts as dual purpose mutex:
752 * - serializes accesses to fw_device_idr,
753 * - serializes accesses to fw_device.config_rom/.config_rom_length and
754 * fw_unit.directory, unless those accesses happen at safe occasions
755 */
756DECLARE_RWSEM(fw_device_rwsem);
757
758DEFINE_IDR(fw_device_idr);
759int fw_cdev_major;
760
761struct fw_device *fw_device_get_by_devt(dev_t devt)
762{
763 struct fw_device *device;
764
765 down_read(&fw_device_rwsem);
766 device = idr_find(&fw_device_idr, MINOR(devt));
767 if (device)
768 fw_device_get(device);
769 up_read(&fw_device_rwsem);
770
771 return device;
772}
773
774struct workqueue_struct *fw_workqueue;
775EXPORT_SYMBOL(fw_workqueue);
776
777static void fw_schedule_device_work(struct fw_device *device,
778 unsigned long delay)
779{
780 queue_delayed_work(fw_workqueue, &device->work, delay);
781}
782
783/*
784 * These defines control the retry behavior for reading the config
785 * rom. It shouldn't be necessary to tweak these; if the device
786 * doesn't respond to a config rom read within 10 seconds, it's not
787 * going to respond at all. As for the initial delay, a lot of
788 * devices will be able to respond within half a second after bus
789 * reset. On the other hand, it's not really worth being more
790 * aggressive than that, since it scales pretty well; if 10 devices
791 * are plugged in, they're all getting read within one second.
792 */
793
794#define MAX_RETRIES 10
795#define RETRY_DELAY (3 * HZ)
796#define INITIAL_DELAY (HZ / 2)
797#define SHUTDOWN_DELAY (2 * HZ)
798
799static void fw_device_shutdown(struct work_struct *work)
800{
801 struct fw_device *device =
802 container_of(work, struct fw_device, work.work);
803 int minor = MINOR(device->device.devt);
804
805 if (time_before64(get_jiffies_64(),
806 device->card->reset_jiffies + SHUTDOWN_DELAY)
807 && !list_empty(&device->card->link)) {
808 fw_schedule_device_work(device, SHUTDOWN_DELAY);
809 return;
810 }
811
812 if (atomic_cmpxchg(&device->state,
813 FW_DEVICE_GONE,
814 FW_DEVICE_SHUTDOWN) != FW_DEVICE_GONE)
815 return;
816
817 fw_device_cdev_remove(device);
818 device_for_each_child(&device->device, NULL, shutdown_unit);
819 device_unregister(&device->device);
820
821 down_write(&fw_device_rwsem);
822 idr_remove(&fw_device_idr, minor);
823 up_write(&fw_device_rwsem);
824
825 fw_device_put(device);
826}
827
828static void fw_device_release(struct device *dev)
829{
830 struct fw_device *device = fw_device(dev);
831 struct fw_card *card = device->card;
832 unsigned long flags;
833
834 /*
835 * Take the card lock so we don't set this to NULL while a
836 * FW_NODE_UPDATED callback is being handled or while the
837 * bus manager work looks at this node.
838 */
839 spin_lock_irqsave(&card->lock, flags);
840 device->node->data = NULL;
841 spin_unlock_irqrestore(&card->lock, flags);
842
843 fw_node_put(device->node);
844 kfree(device->config_rom);
845 kfree(device);
846 fw_card_put(card);
847}
848
849static struct device_type fw_device_type = {
850 .release = fw_device_release,
851};
852
853static bool is_fw_device(struct device *dev)
854{
855 return dev->type == &fw_device_type;
856}
857
858static int update_unit(struct device *dev, void *data)
859{
860 struct fw_unit *unit = fw_unit(dev);
861 struct fw_driver *driver = (struct fw_driver *)dev->driver;
862
863 if (is_fw_unit(dev) && driver != NULL && driver->update != NULL) {
864 device_lock(dev);
865 driver->update(unit);
866 device_unlock(dev);
867 }
868
869 return 0;
870}
871
872static void fw_device_update(struct work_struct *work)
873{
874 struct fw_device *device =
875 container_of(work, struct fw_device, work.work);
876
877 fw_device_cdev_update(device);
878 device_for_each_child(&device->device, NULL, update_unit);
879}
880
881/*
882 * If a device was pending for deletion because its node went away but its
883 * bus info block and root directory header matches that of a newly discovered
884 * device, revive the existing fw_device.
885 * The newly allocated fw_device becomes obsolete instead.
886 */
887static int lookup_existing_device(struct device *dev, void *data)
888{
889 struct fw_device *old = fw_device(dev);
890 struct fw_device *new = data;
891 struct fw_card *card = new->card;
892 int match = 0;
893
894 if (!is_fw_device(dev))
895 return 0;
896
897 down_read(&fw_device_rwsem); /* serialize config_rom access */
898 spin_lock_irq(&card->lock); /* serialize node access */
899
900 if (memcmp(old->config_rom, new->config_rom, 6 * 4) == 0 &&
901 atomic_cmpxchg(&old->state,
902 FW_DEVICE_GONE,
903 FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
904 struct fw_node *current_node = new->node;
905 struct fw_node *obsolete_node = old->node;
906
907 new->node = obsolete_node;
908 new->node->data = new;
909 old->node = current_node;
910 old->node->data = old;
911
912 old->max_speed = new->max_speed;
913 old->node_id = current_node->node_id;
914 smp_wmb(); /* update node_id before generation */
915 old->generation = card->generation;
916 old->config_rom_retries = 0;
917 fw_notice(card, "rediscovered device %s\n", dev_name(dev));
918
919 old->workfn = fw_device_update;
920 fw_schedule_device_work(old, 0);
921
922 if (current_node == card->root_node)
923 fw_schedule_bm_work(card, 0);
924
925 match = 1;
926 }
927
928 spin_unlock_irq(&card->lock);
929 up_read(&fw_device_rwsem);
930
931 return match;
932}
933
934enum { BC_UNKNOWN = 0, BC_UNIMPLEMENTED, BC_IMPLEMENTED, };
935
936static void set_broadcast_channel(struct fw_device *device, int generation)
937{
938 struct fw_card *card = device->card;
939 __be32 data;
940 int rcode;
941
942 if (!card->broadcast_channel_allocated)
943 return;
944
945 /*
946 * The Broadcast_Channel Valid bit is required by nodes which want to
947 * transmit on this channel. Such transmissions are practically
948 * exclusive to IP over 1394 (RFC 2734). IP capable nodes are required
949 * to be IRM capable and have a max_rec of 8 or more. We use this fact
950 * to narrow down to which nodes we send Broadcast_Channel updates.
951 */
952 if (!device->irmc || device->max_rec < 8)
953 return;
954
955 /*
956 * Some 1394-1995 nodes crash if this 1394a-2000 register is written.
957 * Perform a read test first.
958 */
959 if (device->bc_implemented == BC_UNKNOWN) {
960 rcode = fw_run_transaction(card, TCODE_READ_QUADLET_REQUEST,
961 device->node_id, generation, device->max_speed,
962 CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
963 &data, 4);
964 switch (rcode) {
965 case RCODE_COMPLETE:
966 if (data & cpu_to_be32(1 << 31)) {
967 device->bc_implemented = BC_IMPLEMENTED;
968 break;
969 }
970 /* else fall through to case address error */
971 case RCODE_ADDRESS_ERROR:
972 device->bc_implemented = BC_UNIMPLEMENTED;
973 }
974 }
975
976 if (device->bc_implemented == BC_IMPLEMENTED) {
977 data = cpu_to_be32(BROADCAST_CHANNEL_INITIAL |
978 BROADCAST_CHANNEL_VALID);
979 fw_run_transaction(card, TCODE_WRITE_QUADLET_REQUEST,
980 device->node_id, generation, device->max_speed,
981 CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
982 &data, 4);
983 }
984}
985
986int fw_device_set_broadcast_channel(struct device *dev, void *gen)
987{
988 if (is_fw_device(dev))
989 set_broadcast_channel(fw_device(dev), (long)gen);
990
991 return 0;
992}
993
994static void fw_device_init(struct work_struct *work)
995{
996 struct fw_device *device =
997 container_of(work, struct fw_device, work.work);
998 struct fw_card *card = device->card;
999 struct device *revived_dev;
1000 int minor, ret;
1001
1002 /*
1003 * All failure paths here set node->data to NULL, so that we
1004 * don't try to do device_for_each_child() on a kfree()'d
1005 * device.
1006 */
1007
1008 ret = read_config_rom(device, device->generation);
1009 if (ret != RCODE_COMPLETE) {
1010 if (device->config_rom_retries < MAX_RETRIES &&
1011 atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
1012 device->config_rom_retries++;
1013 fw_schedule_device_work(device, RETRY_DELAY);
1014 } else {
1015 if (device->node->link_on)
1016 fw_notice(card, "giving up on node %x: reading config rom failed: %s\n",
1017 device->node_id,
1018 fw_rcode_string(ret));
1019 if (device->node == card->root_node)
1020 fw_schedule_bm_work(card, 0);
1021 fw_device_release(&device->device);
1022 }
1023 return;
1024 }
1025
1026 revived_dev = device_find_child(card->device,
1027 device, lookup_existing_device);
1028 if (revived_dev) {
1029 put_device(revived_dev);
1030 fw_device_release(&device->device);
1031
1032 return;
1033 }
1034
1035 device_initialize(&device->device);
1036
1037 fw_device_get(device);
1038 down_write(&fw_device_rwsem);
1039 minor = idr_alloc(&fw_device_idr, device, 0, 1 << MINORBITS,
1040 GFP_KERNEL);
1041 up_write(&fw_device_rwsem);
1042
1043 if (minor < 0)
1044 goto error;
1045
1046 device->device.bus = &fw_bus_type;
1047 device->device.type = &fw_device_type;
1048 device->device.parent = card->device;
1049 device->device.devt = MKDEV(fw_cdev_major, minor);
1050 dev_set_name(&device->device, "fw%d", minor);
1051
1052 BUILD_BUG_ON(ARRAY_SIZE(device->attribute_group.attrs) <
1053 ARRAY_SIZE(fw_device_attributes) +
1054 ARRAY_SIZE(config_rom_attributes));
1055 init_fw_attribute_group(&device->device,
1056 fw_device_attributes,
1057 &device->attribute_group);
1058
1059 if (device_add(&device->device)) {
1060 fw_err(card, "failed to add device\n");
1061 goto error_with_cdev;
1062 }
1063
1064 create_units(device);
1065
1066 /*
1067 * Transition the device to running state. If it got pulled
1068 * out from under us while we did the intialization work, we
1069 * have to shut down the device again here. Normally, though,
1070 * fw_node_event will be responsible for shutting it down when
1071 * necessary. We have to use the atomic cmpxchg here to avoid
1072 * racing with the FW_NODE_DESTROYED case in
1073 * fw_node_event().
1074 */
1075 if (atomic_cmpxchg(&device->state,
1076 FW_DEVICE_INITIALIZING,
1077 FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
1078 device->workfn = fw_device_shutdown;
1079 fw_schedule_device_work(device, SHUTDOWN_DELAY);
1080 } else {
1081 fw_notice(card, "created device %s: GUID %08x%08x, S%d00\n",
1082 dev_name(&device->device),
1083 device->config_rom[3], device->config_rom[4],
1084 1 << device->max_speed);
1085 device->config_rom_retries = 0;
1086
1087 set_broadcast_channel(device, device->generation);
1088
1089 add_device_randomness(&device->config_rom[3], 8);
1090 }
1091
1092 /*
1093 * Reschedule the IRM work if we just finished reading the
1094 * root node config rom. If this races with a bus reset we
1095 * just end up running the IRM work a couple of extra times -
1096 * pretty harmless.
1097 */
1098 if (device->node == card->root_node)
1099 fw_schedule_bm_work(card, 0);
1100
1101 return;
1102
1103 error_with_cdev:
1104 down_write(&fw_device_rwsem);
1105 idr_remove(&fw_device_idr, minor);
1106 up_write(&fw_device_rwsem);
1107 error:
1108 fw_device_put(device); /* fw_device_idr's reference */
1109
1110 put_device(&device->device); /* our reference */
1111}
1112
1113/* Reread and compare bus info block and header of root directory */
1114static int reread_config_rom(struct fw_device *device, int generation,
1115 bool *changed)
1116{
1117 u32 q;
1118 int i, rcode;
1119
1120 for (i = 0; i < 6; i++) {
1121 rcode = read_rom(device, generation, i, &q);
1122 if (rcode != RCODE_COMPLETE)
1123 return rcode;
1124
1125 if (i == 0 && q == 0)
1126 /* inaccessible (see read_config_rom); retry later */
1127 return RCODE_BUSY;
1128
1129 if (q != device->config_rom[i]) {
1130 *changed = true;
1131 return RCODE_COMPLETE;
1132 }
1133 }
1134
1135 *changed = false;
1136 return RCODE_COMPLETE;
1137}
1138
1139static void fw_device_refresh(struct work_struct *work)
1140{
1141 struct fw_device *device =
1142 container_of(work, struct fw_device, work.work);
1143 struct fw_card *card = device->card;
1144 int ret, node_id = device->node_id;
1145 bool changed;
1146
1147 ret = reread_config_rom(device, device->generation, &changed);
1148 if (ret != RCODE_COMPLETE)
1149 goto failed_config_rom;
1150
1151 if (!changed) {
1152 if (atomic_cmpxchg(&device->state,
1153 FW_DEVICE_INITIALIZING,
1154 FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
1155 goto gone;
1156
1157 fw_device_update(work);
1158 device->config_rom_retries = 0;
1159 goto out;
1160 }
1161
1162 /*
1163 * Something changed. We keep things simple and don't investigate
1164 * further. We just destroy all previous units and create new ones.
1165 */
1166 device_for_each_child(&device->device, NULL, shutdown_unit);
1167
1168 ret = read_config_rom(device, device->generation);
1169 if (ret != RCODE_COMPLETE)
1170 goto failed_config_rom;
1171
1172 fw_device_cdev_update(device);
1173 create_units(device);
1174
1175 /* Userspace may want to re-read attributes. */
1176 kobject_uevent(&device->device.kobj, KOBJ_CHANGE);
1177
1178 if (atomic_cmpxchg(&device->state,
1179 FW_DEVICE_INITIALIZING,
1180 FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
1181 goto gone;
1182
1183 fw_notice(card, "refreshed device %s\n", dev_name(&device->device));
1184 device->config_rom_retries = 0;
1185 goto out;
1186
1187 failed_config_rom:
1188 if (device->config_rom_retries < MAX_RETRIES &&
1189 atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
1190 device->config_rom_retries++;
1191 fw_schedule_device_work(device, RETRY_DELAY);
1192 return;
1193 }
1194
1195 fw_notice(card, "giving up on refresh of device %s: %s\n",
1196 dev_name(&device->device), fw_rcode_string(ret));
1197 gone:
1198 atomic_set(&device->state, FW_DEVICE_GONE);
1199 device->workfn = fw_device_shutdown;
1200 fw_schedule_device_work(device, SHUTDOWN_DELAY);
1201 out:
1202 if (node_id == card->root_node->node_id)
1203 fw_schedule_bm_work(card, 0);
1204}
1205
1206static void fw_device_workfn(struct work_struct *work)
1207{
1208 struct fw_device *device = container_of(to_delayed_work(work),
1209 struct fw_device, work);
1210 device->workfn(work);
1211}
1212
1213void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
1214{
1215 struct fw_device *device;
1216
1217 switch (event) {
1218 case FW_NODE_CREATED:
1219 /*
1220 * Attempt to scan the node, regardless whether its self ID has
1221 * the L (link active) flag set or not. Some broken devices
1222 * send L=0 but have an up-and-running link; others send L=1
1223 * without actually having a link.
1224 */
1225 create:
1226 device = kzalloc(sizeof(*device), GFP_ATOMIC);
1227 if (device == NULL)
1228 break;
1229
1230 /*
1231 * Do minimal intialization of the device here, the
1232 * rest will happen in fw_device_init().
1233 *
1234 * Attention: A lot of things, even fw_device_get(),
1235 * cannot be done before fw_device_init() finished!
1236 * You can basically just check device->state and
1237 * schedule work until then, but only while holding
1238 * card->lock.
1239 */
1240 atomic_set(&device->state, FW_DEVICE_INITIALIZING);
1241 device->card = fw_card_get(card);
1242 device->node = fw_node_get(node);
1243 device->node_id = node->node_id;
1244 device->generation = card->generation;
1245 device->is_local = node == card->local_node;
1246 mutex_init(&device->client_list_mutex);
1247 INIT_LIST_HEAD(&device->client_list);
1248
1249 /*
1250 * Set the node data to point back to this device so
1251 * FW_NODE_UPDATED callbacks can update the node_id
1252 * and generation for the device.
1253 */
1254 node->data = device;
1255
1256 /*
1257 * Many devices are slow to respond after bus resets,
1258 * especially if they are bus powered and go through
1259 * power-up after getting plugged in. We schedule the
1260 * first config rom scan half a second after bus reset.
1261 */
1262 device->workfn = fw_device_init;
1263 INIT_DELAYED_WORK(&device->work, fw_device_workfn);
1264 fw_schedule_device_work(device, INITIAL_DELAY);
1265 break;
1266
1267 case FW_NODE_INITIATED_RESET:
1268 case FW_NODE_LINK_ON:
1269 device = node->data;
1270 if (device == NULL)
1271 goto create;
1272
1273 device->node_id = node->node_id;
1274 smp_wmb(); /* update node_id before generation */
1275 device->generation = card->generation;
1276 if (atomic_cmpxchg(&device->state,
1277 FW_DEVICE_RUNNING,
1278 FW_DEVICE_INITIALIZING) == FW_DEVICE_RUNNING) {
1279 device->workfn = fw_device_refresh;
1280 fw_schedule_device_work(device,
1281 device->is_local ? 0 : INITIAL_DELAY);
1282 }
1283 break;
1284
1285 case FW_NODE_UPDATED:
1286 device = node->data;
1287 if (device == NULL)
1288 break;
1289
1290 device->node_id = node->node_id;
1291 smp_wmb(); /* update node_id before generation */
1292 device->generation = card->generation;
1293 if (atomic_read(&device->state) == FW_DEVICE_RUNNING) {
1294 device->workfn = fw_device_update;
1295 fw_schedule_device_work(device, 0);
1296 }
1297 break;
1298
1299 case FW_NODE_DESTROYED:
1300 case FW_NODE_LINK_OFF:
1301 if (!node->data)
1302 break;
1303
1304 /*
1305 * Destroy the device associated with the node. There
1306 * are two cases here: either the device is fully
1307 * initialized (FW_DEVICE_RUNNING) or we're in the
1308 * process of reading its config rom
1309 * (FW_DEVICE_INITIALIZING). If it is fully
1310 * initialized we can reuse device->work to schedule a
1311 * full fw_device_shutdown(). If not, there's work
1312 * scheduled to read it's config rom, and we just put
1313 * the device in shutdown state to have that code fail
1314 * to create the device.
1315 */
1316 device = node->data;
1317 if (atomic_xchg(&device->state,
1318 FW_DEVICE_GONE) == FW_DEVICE_RUNNING) {
1319 device->workfn = fw_device_shutdown;
1320 fw_schedule_device_work(device,
1321 list_empty(&card->link) ? 0 : SHUTDOWN_DELAY);
1322 }
1323 break;
1324 }
1325}