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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
44#include "core.h"
45
46void fw_csr_iterator_init(struct fw_csr_iterator *ci, const u32 *p)
47{
48 ci->p = p + 1;
49 ci->end = ci->p + (p[0] >> 16);
50}
51EXPORT_SYMBOL(fw_csr_iterator_init);
52
53int fw_csr_iterator_next(struct fw_csr_iterator *ci, int *key, int *value)
54{
55 *key = *ci->p >> 24;
56 *value = *ci->p & 0xffffff;
57
58 return ci->p++ < ci->end;
59}
60EXPORT_SYMBOL(fw_csr_iterator_next);
61
62static const u32 *search_leaf(const u32 *directory, int search_key)
63{
64 struct fw_csr_iterator ci;
65 int last_key = 0, key, value;
66
67 fw_csr_iterator_init(&ci, directory);
68 while (fw_csr_iterator_next(&ci, &key, &value)) {
69 if (last_key == search_key &&
70 key == (CSR_DESCRIPTOR | CSR_LEAF))
71 return ci.p - 1 + value;
72
73 last_key = key;
74 }
75
76 return NULL;
77}
78
79static int textual_leaf_to_string(const u32 *block, char *buf, size_t size)
80{
81 unsigned int quadlets, i;
82 char c;
83
84 if (!size || !buf)
85 return -EINVAL;
86
87 quadlets = min(block[0] >> 16, 256U);
88 if (quadlets < 2)
89 return -ENODATA;
90
91 if (block[1] != 0 || block[2] != 0)
92 /* unknown language/character set */
93 return -ENODATA;
94
95 block += 3;
96 quadlets -= 2;
97 for (i = 0; i < quadlets * 4 && i < size - 1; i++) {
98 c = block[i / 4] >> (24 - 8 * (i % 4));
99 if (c == '\0')
100 break;
101 buf[i] = c;
102 }
103 buf[i] = '\0';
104
105 return i;
106}
107
108/**
109 * fw_csr_string() - reads a string from the configuration ROM
110 * @directory: e.g. root directory or unit directory
111 * @key: the key of the preceding directory entry
112 * @buf: where to put the string
113 * @size: size of @buf, in bytes
114 *
115 * The string is taken from a minimal ASCII text descriptor leaf after
116 * the immediate entry with @key. The string is zero-terminated.
117 * Returns strlen(buf) or a negative error code.
118 */
119int fw_csr_string(const u32 *directory, int key, char *buf, size_t size)
120{
121 const u32 *leaf = search_leaf(directory, key);
122 if (!leaf)
123 return -ENOENT;
124
125 return textual_leaf_to_string(leaf, buf, size);
126}
127EXPORT_SYMBOL(fw_csr_string);
128
129static void get_ids(const u32 *directory, int *id)
130{
131 struct fw_csr_iterator ci;
132 int key, value;
133
134 fw_csr_iterator_init(&ci, directory);
135 while (fw_csr_iterator_next(&ci, &key, &value)) {
136 switch (key) {
137 case CSR_VENDOR: id[0] = value; break;
138 case CSR_MODEL: id[1] = value; break;
139 case CSR_SPECIFIER_ID: id[2] = value; break;
140 case CSR_VERSION: id[3] = value; break;
141 }
142 }
143}
144
145static void get_modalias_ids(struct fw_unit *unit, int *id)
146{
147 get_ids(&fw_parent_device(unit)->config_rom[5], id);
148 get_ids(unit->directory, id);
149}
150
151static bool match_ids(const struct ieee1394_device_id *id_table, int *id)
152{
153 int match = 0;
154
155 if (id[0] == id_table->vendor_id)
156 match |= IEEE1394_MATCH_VENDOR_ID;
157 if (id[1] == id_table->model_id)
158 match |= IEEE1394_MATCH_MODEL_ID;
159 if (id[2] == id_table->specifier_id)
160 match |= IEEE1394_MATCH_SPECIFIER_ID;
161 if (id[3] == id_table->version)
162 match |= IEEE1394_MATCH_VERSION;
163
164 return (match & id_table->match_flags) == id_table->match_flags;
165}
166
167static bool is_fw_unit(struct device *dev);
168
169static int fw_unit_match(struct device *dev, 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 /* We only allow binding to fw_units. */
176 if (!is_fw_unit(dev))
177 return 0;
178
179 get_modalias_ids(fw_unit(dev), id);
180
181 for (; id_table->match_flags != 0; id_table++)
182 if (match_ids(id_table, id))
183 return 1;
184
185 return 0;
186}
187
188static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
189{
190 int id[] = {0, 0, 0, 0};
191
192 get_modalias_ids(unit, id);
193
194 return snprintf(buffer, buffer_size,
195 "ieee1394:ven%08Xmo%08Xsp%08Xver%08X",
196 id[0], id[1], id[2], id[3]);
197}
198
199static int fw_unit_uevent(struct device *dev, struct kobj_uevent_env *env)
200{
201 struct fw_unit *unit = fw_unit(dev);
202 char modalias[64];
203
204 get_modalias(unit, modalias, sizeof(modalias));
205
206 if (add_uevent_var(env, "MODALIAS=%s", modalias))
207 return -ENOMEM;
208
209 return 0;
210}
211
212struct bus_type fw_bus_type = {
213 .name = "firewire",
214 .match = fw_unit_match,
215};
216EXPORT_SYMBOL(fw_bus_type);
217
218int fw_device_enable_phys_dma(struct fw_device *device)
219{
220 int generation = device->generation;
221
222 /* device->node_id, accessed below, must not be older than generation */
223 smp_rmb();
224
225 return device->card->driver->enable_phys_dma(device->card,
226 device->node_id,
227 generation);
228}
229EXPORT_SYMBOL(fw_device_enable_phys_dma);
230
231struct config_rom_attribute {
232 struct device_attribute attr;
233 u32 key;
234};
235
236static ssize_t show_immediate(struct device *dev,
237 struct device_attribute *dattr, char *buf)
238{
239 struct config_rom_attribute *attr =
240 container_of(dattr, struct config_rom_attribute, attr);
241 struct fw_csr_iterator ci;
242 const u32 *dir;
243 int key, value, ret = -ENOENT;
244
245 down_read(&fw_device_rwsem);
246
247 if (is_fw_unit(dev))
248 dir = fw_unit(dev)->directory;
249 else
250 dir = fw_device(dev)->config_rom + 5;
251
252 fw_csr_iterator_init(&ci, dir);
253 while (fw_csr_iterator_next(&ci, &key, &value))
254 if (attr->key == key) {
255 ret = snprintf(buf, buf ? PAGE_SIZE : 0,
256 "0x%06x\n", value);
257 break;
258 }
259
260 up_read(&fw_device_rwsem);
261
262 return ret;
263}
264
265#define IMMEDIATE_ATTR(name, key) \
266 { __ATTR(name, S_IRUGO, show_immediate, NULL), key }
267
268static ssize_t show_text_leaf(struct device *dev,
269 struct device_attribute *dattr, char *buf)
270{
271 struct config_rom_attribute *attr =
272 container_of(dattr, struct config_rom_attribute, attr);
273 const u32 *dir;
274 size_t bufsize;
275 char dummy_buf[2];
276 int ret;
277
278 down_read(&fw_device_rwsem);
279
280 if (is_fw_unit(dev))
281 dir = fw_unit(dev)->directory;
282 else
283 dir = fw_device(dev)->config_rom + 5;
284
285 if (buf) {
286 bufsize = PAGE_SIZE - 1;
287 } else {
288 buf = dummy_buf;
289 bufsize = 1;
290 }
291
292 ret = fw_csr_string(dir, attr->key, buf, bufsize);
293
294 if (ret >= 0) {
295 /* Strip trailing whitespace and add newline. */
296 while (ret > 0 && isspace(buf[ret - 1]))
297 ret--;
298 strcpy(buf + ret, "\n");
299 ret++;
300 }
301
302 up_read(&fw_device_rwsem);
303
304 return ret;
305}
306
307#define TEXT_LEAF_ATTR(name, key) \
308 { __ATTR(name, S_IRUGO, show_text_leaf, NULL), key }
309
310static struct config_rom_attribute config_rom_attributes[] = {
311 IMMEDIATE_ATTR(vendor, CSR_VENDOR),
312 IMMEDIATE_ATTR(hardware_version, CSR_HARDWARE_VERSION),
313 IMMEDIATE_ATTR(specifier_id, CSR_SPECIFIER_ID),
314 IMMEDIATE_ATTR(version, CSR_VERSION),
315 IMMEDIATE_ATTR(model, CSR_MODEL),
316 TEXT_LEAF_ATTR(vendor_name, CSR_VENDOR),
317 TEXT_LEAF_ATTR(model_name, CSR_MODEL),
318 TEXT_LEAF_ATTR(hardware_version_name, CSR_HARDWARE_VERSION),
319};
320
321static void init_fw_attribute_group(struct device *dev,
322 struct device_attribute *attrs,
323 struct fw_attribute_group *group)
324{
325 struct device_attribute *attr;
326 int i, j;
327
328 for (j = 0; attrs[j].attr.name != NULL; j++)
329 group->attrs[j] = &attrs[j].attr;
330
331 for (i = 0; i < ARRAY_SIZE(config_rom_attributes); i++) {
332 attr = &config_rom_attributes[i].attr;
333 if (attr->show(dev, attr, NULL) < 0)
334 continue;
335 group->attrs[j++] = &attr->attr;
336 }
337
338 group->attrs[j] = NULL;
339 group->groups[0] = &group->group;
340 group->groups[1] = NULL;
341 group->group.attrs = group->attrs;
342 dev->groups = (const struct attribute_group **) group->groups;
343}
344
345static ssize_t modalias_show(struct device *dev,
346 struct device_attribute *attr, char *buf)
347{
348 struct fw_unit *unit = fw_unit(dev);
349 int length;
350
351 length = get_modalias(unit, buf, PAGE_SIZE);
352 strcpy(buf + length, "\n");
353
354 return length + 1;
355}
356
357static ssize_t rom_index_show(struct device *dev,
358 struct device_attribute *attr, char *buf)
359{
360 struct fw_device *device = fw_device(dev->parent);
361 struct fw_unit *unit = fw_unit(dev);
362
363 return snprintf(buf, PAGE_SIZE, "%d\n",
364 (int)(unit->directory - device->config_rom));
365}
366
367static struct device_attribute fw_unit_attributes[] = {
368 __ATTR_RO(modalias),
369 __ATTR_RO(rom_index),
370 __ATTR_NULL,
371};
372
373static ssize_t config_rom_show(struct device *dev,
374 struct device_attribute *attr, char *buf)
375{
376 struct fw_device *device = fw_device(dev);
377 size_t length;
378
379 down_read(&fw_device_rwsem);
380 length = device->config_rom_length * 4;
381 memcpy(buf, device->config_rom, length);
382 up_read(&fw_device_rwsem);
383
384 return length;
385}
386
387static ssize_t guid_show(struct device *dev,
388 struct device_attribute *attr, char *buf)
389{
390 struct fw_device *device = fw_device(dev);
391 int ret;
392
393 down_read(&fw_device_rwsem);
394 ret = snprintf(buf, PAGE_SIZE, "0x%08x%08x\n",
395 device->config_rom[3], device->config_rom[4]);
396 up_read(&fw_device_rwsem);
397
398 return ret;
399}
400
401static int units_sprintf(char *buf, const u32 *directory)
402{
403 struct fw_csr_iterator ci;
404 int key, value;
405 int specifier_id = 0;
406 int version = 0;
407
408 fw_csr_iterator_init(&ci, directory);
409 while (fw_csr_iterator_next(&ci, &key, &value)) {
410 switch (key) {
411 case CSR_SPECIFIER_ID:
412 specifier_id = value;
413 break;
414 case CSR_VERSION:
415 version = value;
416 break;
417 }
418 }
419
420 return sprintf(buf, "0x%06x:0x%06x ", specifier_id, version);
421}
422
423static ssize_t units_show(struct device *dev,
424 struct device_attribute *attr, char *buf)
425{
426 struct fw_device *device = fw_device(dev);
427 struct fw_csr_iterator ci;
428 int key, value, i = 0;
429
430 down_read(&fw_device_rwsem);
431 fw_csr_iterator_init(&ci, &device->config_rom[5]);
432 while (fw_csr_iterator_next(&ci, &key, &value)) {
433 if (key != (CSR_UNIT | CSR_DIRECTORY))
434 continue;
435 i += units_sprintf(&buf[i], ci.p + value - 1);
436 if (i >= PAGE_SIZE - (8 + 1 + 8 + 1))
437 break;
438 }
439 up_read(&fw_device_rwsem);
440
441 if (i)
442 buf[i - 1] = '\n';
443
444 return i;
445}
446
447static struct device_attribute fw_device_attributes[] = {
448 __ATTR_RO(config_rom),
449 __ATTR_RO(guid),
450 __ATTR_RO(units),
451 __ATTR_NULL,
452};
453
454static int read_rom(struct fw_device *device,
455 int generation, int index, u32 *data)
456{
457 u64 offset = (CSR_REGISTER_BASE | CSR_CONFIG_ROM) + index * 4;
458 int i, rcode;
459
460 /* device->node_id, accessed below, must not be older than generation */
461 smp_rmb();
462
463 for (i = 10; i < 100; i += 10) {
464 rcode = fw_run_transaction(device->card,
465 TCODE_READ_QUADLET_REQUEST, device->node_id,
466 generation, device->max_speed, offset, data, 4);
467 if (rcode != RCODE_BUSY)
468 break;
469 msleep(i);
470 }
471 be32_to_cpus(data);
472
473 return rcode;
474}
475
476#define MAX_CONFIG_ROM_SIZE 256
477
478/*
479 * Read the bus info block, perform a speed probe, and read all of the rest of
480 * the config ROM. We do all this with a cached bus generation. If the bus
481 * generation changes under us, read_config_rom will fail and get retried.
482 * It's better to start all over in this case because the node from which we
483 * are reading the ROM may have changed the ROM during the reset.
484 * Returns either a result code or a negative error code.
485 */
486static int read_config_rom(struct fw_device *device, int generation)
487{
488 struct fw_card *card = device->card;
489 const u32 *old_rom, *new_rom;
490 u32 *rom, *stack;
491 u32 sp, key;
492 int i, end, length, ret;
493
494 rom = kmalloc(sizeof(*rom) * MAX_CONFIG_ROM_SIZE +
495 sizeof(*stack) * MAX_CONFIG_ROM_SIZE, GFP_KERNEL);
496 if (rom == NULL)
497 return -ENOMEM;
498
499 stack = &rom[MAX_CONFIG_ROM_SIZE];
500 memset(rom, 0, sizeof(*rom) * MAX_CONFIG_ROM_SIZE);
501
502 device->max_speed = SCODE_100;
503
504 /* First read the bus info block. */
505 for (i = 0; i < 5; i++) {
506 ret = read_rom(device, generation, i, &rom[i]);
507 if (ret != RCODE_COMPLETE)
508 goto out;
509 /*
510 * As per IEEE1212 7.2, during initialization, devices can
511 * reply with a 0 for the first quadlet of the config
512 * rom to indicate that they are booting (for example,
513 * if the firmware is on the disk of a external
514 * harddisk). In that case we just fail, and the
515 * retry mechanism will try again later.
516 */
517 if (i == 0 && rom[i] == 0) {
518 ret = RCODE_BUSY;
519 goto out;
520 }
521 }
522
523 device->max_speed = device->node->max_speed;
524
525 /*
526 * Determine the speed of
527 * - devices with link speed less than PHY speed,
528 * - devices with 1394b PHY (unless only connected to 1394a PHYs),
529 * - all devices if there are 1394b repeaters.
530 * Note, we cannot use the bus info block's link_spd as starting point
531 * because some buggy firmwares set it lower than necessary and because
532 * 1394-1995 nodes do not have the field.
533 */
534 if ((rom[2] & 0x7) < device->max_speed ||
535 device->max_speed == SCODE_BETA ||
536 card->beta_repeaters_present) {
537 u32 dummy;
538
539 /* for S1600 and S3200 */
540 if (device->max_speed == SCODE_BETA)
541 device->max_speed = card->link_speed;
542
543 while (device->max_speed > SCODE_100) {
544 if (read_rom(device, generation, 0, &dummy) ==
545 RCODE_COMPLETE)
546 break;
547 device->max_speed--;
548 }
549 }
550
551 /*
552 * Now parse the config rom. The config rom is a recursive
553 * directory structure so we parse it using a stack of
554 * references to the blocks that make up the structure. We
555 * push a reference to the root directory on the stack to
556 * start things off.
557 */
558 length = i;
559 sp = 0;
560 stack[sp++] = 0xc0000005;
561 while (sp > 0) {
562 /*
563 * Pop the next block reference of the stack. The
564 * lower 24 bits is the offset into the config rom,
565 * the upper 8 bits are the type of the reference the
566 * block.
567 */
568 key = stack[--sp];
569 i = key & 0xffffff;
570 if (WARN_ON(i >= MAX_CONFIG_ROM_SIZE)) {
571 ret = -ENXIO;
572 goto out;
573 }
574
575 /* Read header quadlet for the block to get the length. */
576 ret = read_rom(device, generation, i, &rom[i]);
577 if (ret != RCODE_COMPLETE)
578 goto out;
579 end = i + (rom[i] >> 16) + 1;
580 if (end > MAX_CONFIG_ROM_SIZE) {
581 /*
582 * This block extends outside the config ROM which is
583 * a firmware bug. Ignore this whole block, i.e.
584 * simply set a fake block length of 0.
585 */
586 fw_err(card, "skipped invalid ROM block %x at %llx\n",
587 rom[i],
588 i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
589 rom[i] = 0;
590 end = i;
591 }
592 i++;
593
594 /*
595 * Now read in the block. If this is a directory
596 * block, check the entries as we read them to see if
597 * it references another block, and push it in that case.
598 */
599 for (; i < end; i++) {
600 ret = read_rom(device, generation, i, &rom[i]);
601 if (ret != RCODE_COMPLETE)
602 goto out;
603
604 if ((key >> 30) != 3 || (rom[i] >> 30) < 2)
605 continue;
606 /*
607 * Offset points outside the ROM. May be a firmware
608 * bug or an Extended ROM entry (IEEE 1212-2001 clause
609 * 7.7.18). Simply overwrite this pointer here by a
610 * fake immediate entry so that later iterators over
611 * the ROM don't have to check offsets all the time.
612 */
613 if (i + (rom[i] & 0xffffff) >= MAX_CONFIG_ROM_SIZE) {
614 fw_err(card,
615 "skipped unsupported ROM entry %x at %llx\n",
616 rom[i],
617 i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
618 rom[i] = 0;
619 continue;
620 }
621 stack[sp++] = i + rom[i];
622 }
623 if (length < i)
624 length = i;
625 }
626
627 old_rom = device->config_rom;
628 new_rom = kmemdup(rom, length * 4, GFP_KERNEL);
629 if (new_rom == NULL) {
630 ret = -ENOMEM;
631 goto out;
632 }
633
634 down_write(&fw_device_rwsem);
635 device->config_rom = new_rom;
636 device->config_rom_length = length;
637 up_write(&fw_device_rwsem);
638
639 kfree(old_rom);
640 ret = RCODE_COMPLETE;
641 device->max_rec = rom[2] >> 12 & 0xf;
642 device->cmc = rom[2] >> 30 & 1;
643 device->irmc = rom[2] >> 31 & 1;
644 out:
645 kfree(rom);
646
647 return ret;
648}
649
650static void fw_unit_release(struct device *dev)
651{
652 struct fw_unit *unit = fw_unit(dev);
653
654 fw_device_put(fw_parent_device(unit));
655 kfree(unit);
656}
657
658static struct device_type fw_unit_type = {
659 .uevent = fw_unit_uevent,
660 .release = fw_unit_release,
661};
662
663static bool is_fw_unit(struct device *dev)
664{
665 return dev->type == &fw_unit_type;
666}
667
668static void create_units(struct fw_device *device)
669{
670 struct fw_csr_iterator ci;
671 struct fw_unit *unit;
672 int key, value, i;
673
674 i = 0;
675 fw_csr_iterator_init(&ci, &device->config_rom[5]);
676 while (fw_csr_iterator_next(&ci, &key, &value)) {
677 if (key != (CSR_UNIT | CSR_DIRECTORY))
678 continue;
679
680 /*
681 * Get the address of the unit directory and try to
682 * match the drivers id_tables against it.
683 */
684 unit = kzalloc(sizeof(*unit), GFP_KERNEL);
685 if (unit == NULL) {
686 fw_err(device->card, "out of memory for unit\n");
687 continue;
688 }
689
690 unit->directory = ci.p + value - 1;
691 unit->device.bus = &fw_bus_type;
692 unit->device.type = &fw_unit_type;
693 unit->device.parent = &device->device;
694 dev_set_name(&unit->device, "%s.%d", dev_name(&device->device), i++);
695
696 BUILD_BUG_ON(ARRAY_SIZE(unit->attribute_group.attrs) <
697 ARRAY_SIZE(fw_unit_attributes) +
698 ARRAY_SIZE(config_rom_attributes));
699 init_fw_attribute_group(&unit->device,
700 fw_unit_attributes,
701 &unit->attribute_group);
702
703 if (device_register(&unit->device) < 0)
704 goto skip_unit;
705
706 fw_device_get(device);
707 continue;
708
709 skip_unit:
710 kfree(unit);
711 }
712}
713
714static int shutdown_unit(struct device *device, void *data)
715{
716 device_unregister(device);
717
718 return 0;
719}
720
721/*
722 * fw_device_rwsem acts as dual purpose mutex:
723 * - serializes accesses to fw_device_idr,
724 * - serializes accesses to fw_device.config_rom/.config_rom_length and
725 * fw_unit.directory, unless those accesses happen at safe occasions
726 */
727DECLARE_RWSEM(fw_device_rwsem);
728
729DEFINE_IDR(fw_device_idr);
730int fw_cdev_major;
731
732struct fw_device *fw_device_get_by_devt(dev_t devt)
733{
734 struct fw_device *device;
735
736 down_read(&fw_device_rwsem);
737 device = idr_find(&fw_device_idr, MINOR(devt));
738 if (device)
739 fw_device_get(device);
740 up_read(&fw_device_rwsem);
741
742 return device;
743}
744
745struct workqueue_struct *fw_workqueue;
746EXPORT_SYMBOL(fw_workqueue);
747
748static void fw_schedule_device_work(struct fw_device *device,
749 unsigned long delay)
750{
751 queue_delayed_work(fw_workqueue, &device->work, delay);
752}
753
754/*
755 * These defines control the retry behavior for reading the config
756 * rom. It shouldn't be necessary to tweak these; if the device
757 * doesn't respond to a config rom read within 10 seconds, it's not
758 * going to respond at all. As for the initial delay, a lot of
759 * devices will be able to respond within half a second after bus
760 * reset. On the other hand, it's not really worth being more
761 * aggressive than that, since it scales pretty well; if 10 devices
762 * are plugged in, they're all getting read within one second.
763 */
764
765#define MAX_RETRIES 10
766#define RETRY_DELAY (3 * HZ)
767#define INITIAL_DELAY (HZ / 2)
768#define SHUTDOWN_DELAY (2 * HZ)
769
770static void fw_device_shutdown(struct work_struct *work)
771{
772 struct fw_device *device =
773 container_of(work, struct fw_device, work.work);
774 int minor = MINOR(device->device.devt);
775
776 if (time_before64(get_jiffies_64(),
777 device->card->reset_jiffies + SHUTDOWN_DELAY)
778 && !list_empty(&device->card->link)) {
779 fw_schedule_device_work(device, SHUTDOWN_DELAY);
780 return;
781 }
782
783 if (atomic_cmpxchg(&device->state,
784 FW_DEVICE_GONE,
785 FW_DEVICE_SHUTDOWN) != FW_DEVICE_GONE)
786 return;
787
788 fw_device_cdev_remove(device);
789 device_for_each_child(&device->device, NULL, shutdown_unit);
790 device_unregister(&device->device);
791
792 down_write(&fw_device_rwsem);
793 idr_remove(&fw_device_idr, minor);
794 up_write(&fw_device_rwsem);
795
796 fw_device_put(device);
797}
798
799static void fw_device_release(struct device *dev)
800{
801 struct fw_device *device = fw_device(dev);
802 struct fw_card *card = device->card;
803 unsigned long flags;
804
805 /*
806 * Take the card lock so we don't set this to NULL while a
807 * FW_NODE_UPDATED callback is being handled or while the
808 * bus manager work looks at this node.
809 */
810 spin_lock_irqsave(&card->lock, flags);
811 device->node->data = NULL;
812 spin_unlock_irqrestore(&card->lock, flags);
813
814 fw_node_put(device->node);
815 kfree(device->config_rom);
816 kfree(device);
817 fw_card_put(card);
818}
819
820static struct device_type fw_device_type = {
821 .release = fw_device_release,
822};
823
824static bool is_fw_device(struct device *dev)
825{
826 return dev->type == &fw_device_type;
827}
828
829static int update_unit(struct device *dev, void *data)
830{
831 struct fw_unit *unit = fw_unit(dev);
832 struct fw_driver *driver = (struct fw_driver *)dev->driver;
833
834 if (is_fw_unit(dev) && driver != NULL && driver->update != NULL) {
835 device_lock(dev);
836 driver->update(unit);
837 device_unlock(dev);
838 }
839
840 return 0;
841}
842
843static void fw_device_update(struct work_struct *work)
844{
845 struct fw_device *device =
846 container_of(work, struct fw_device, work.work);
847
848 fw_device_cdev_update(device);
849 device_for_each_child(&device->device, NULL, update_unit);
850}
851
852/*
853 * If a device was pending for deletion because its node went away but its
854 * bus info block and root directory header matches that of a newly discovered
855 * device, revive the existing fw_device.
856 * The newly allocated fw_device becomes obsolete instead.
857 */
858static int lookup_existing_device(struct device *dev, void *data)
859{
860 struct fw_device *old = fw_device(dev);
861 struct fw_device *new = data;
862 struct fw_card *card = new->card;
863 int match = 0;
864
865 if (!is_fw_device(dev))
866 return 0;
867
868 down_read(&fw_device_rwsem); /* serialize config_rom access */
869 spin_lock_irq(&card->lock); /* serialize node access */
870
871 if (memcmp(old->config_rom, new->config_rom, 6 * 4) == 0 &&
872 atomic_cmpxchg(&old->state,
873 FW_DEVICE_GONE,
874 FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
875 struct fw_node *current_node = new->node;
876 struct fw_node *obsolete_node = old->node;
877
878 new->node = obsolete_node;
879 new->node->data = new;
880 old->node = current_node;
881 old->node->data = old;
882
883 old->max_speed = new->max_speed;
884 old->node_id = current_node->node_id;
885 smp_wmb(); /* update node_id before generation */
886 old->generation = card->generation;
887 old->config_rom_retries = 0;
888 fw_notice(card, "rediscovered device %s\n", dev_name(dev));
889
890 PREPARE_DELAYED_WORK(&old->work, fw_device_update);
891 fw_schedule_device_work(old, 0);
892
893 if (current_node == card->root_node)
894 fw_schedule_bm_work(card, 0);
895
896 match = 1;
897 }
898
899 spin_unlock_irq(&card->lock);
900 up_read(&fw_device_rwsem);
901
902 return match;
903}
904
905enum { BC_UNKNOWN = 0, BC_UNIMPLEMENTED, BC_IMPLEMENTED, };
906
907static void set_broadcast_channel(struct fw_device *device, int generation)
908{
909 struct fw_card *card = device->card;
910 __be32 data;
911 int rcode;
912
913 if (!card->broadcast_channel_allocated)
914 return;
915
916 /*
917 * The Broadcast_Channel Valid bit is required by nodes which want to
918 * transmit on this channel. Such transmissions are practically
919 * exclusive to IP over 1394 (RFC 2734). IP capable nodes are required
920 * to be IRM capable and have a max_rec of 8 or more. We use this fact
921 * to narrow down to which nodes we send Broadcast_Channel updates.
922 */
923 if (!device->irmc || device->max_rec < 8)
924 return;
925
926 /*
927 * Some 1394-1995 nodes crash if this 1394a-2000 register is written.
928 * Perform a read test first.
929 */
930 if (device->bc_implemented == BC_UNKNOWN) {
931 rcode = fw_run_transaction(card, TCODE_READ_QUADLET_REQUEST,
932 device->node_id, generation, device->max_speed,
933 CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
934 &data, 4);
935 switch (rcode) {
936 case RCODE_COMPLETE:
937 if (data & cpu_to_be32(1 << 31)) {
938 device->bc_implemented = BC_IMPLEMENTED;
939 break;
940 }
941 /* else fall through to case address error */
942 case RCODE_ADDRESS_ERROR:
943 device->bc_implemented = BC_UNIMPLEMENTED;
944 }
945 }
946
947 if (device->bc_implemented == BC_IMPLEMENTED) {
948 data = cpu_to_be32(BROADCAST_CHANNEL_INITIAL |
949 BROADCAST_CHANNEL_VALID);
950 fw_run_transaction(card, TCODE_WRITE_QUADLET_REQUEST,
951 device->node_id, generation, device->max_speed,
952 CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
953 &data, 4);
954 }
955}
956
957int fw_device_set_broadcast_channel(struct device *dev, void *gen)
958{
959 if (is_fw_device(dev))
960 set_broadcast_channel(fw_device(dev), (long)gen);
961
962 return 0;
963}
964
965static void fw_device_init(struct work_struct *work)
966{
967 struct fw_device *device =
968 container_of(work, struct fw_device, work.work);
969 struct fw_card *card = device->card;
970 struct device *revived_dev;
971 int minor, ret;
972
973 /*
974 * All failure paths here set node->data to NULL, so that we
975 * don't try to do device_for_each_child() on a kfree()'d
976 * device.
977 */
978
979 ret = read_config_rom(device, device->generation);
980 if (ret != RCODE_COMPLETE) {
981 if (device->config_rom_retries < MAX_RETRIES &&
982 atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
983 device->config_rom_retries++;
984 fw_schedule_device_work(device, RETRY_DELAY);
985 } else {
986 if (device->node->link_on)
987 fw_notice(card, "giving up on node %x: reading config rom failed: %s\n",
988 device->node_id,
989 fw_rcode_string(ret));
990 if (device->node == card->root_node)
991 fw_schedule_bm_work(card, 0);
992 fw_device_release(&device->device);
993 }
994 return;
995 }
996
997 revived_dev = device_find_child(card->device,
998 device, lookup_existing_device);
999 if (revived_dev) {
1000 put_device(revived_dev);
1001 fw_device_release(&device->device);
1002
1003 return;
1004 }
1005
1006 device_initialize(&device->device);
1007
1008 fw_device_get(device);
1009 down_write(&fw_device_rwsem);
1010 ret = idr_pre_get(&fw_device_idr, GFP_KERNEL) ?
1011 idr_get_new(&fw_device_idr, device, &minor) :
1012 -ENOMEM;
1013 up_write(&fw_device_rwsem);
1014
1015 if (ret < 0)
1016 goto error;
1017
1018 device->device.bus = &fw_bus_type;
1019 device->device.type = &fw_device_type;
1020 device->device.parent = card->device;
1021 device->device.devt = MKDEV(fw_cdev_major, minor);
1022 dev_set_name(&device->device, "fw%d", minor);
1023
1024 BUILD_BUG_ON(ARRAY_SIZE(device->attribute_group.attrs) <
1025 ARRAY_SIZE(fw_device_attributes) +
1026 ARRAY_SIZE(config_rom_attributes));
1027 init_fw_attribute_group(&device->device,
1028 fw_device_attributes,
1029 &device->attribute_group);
1030
1031 if (device_add(&device->device)) {
1032 fw_err(card, "failed to add device\n");
1033 goto error_with_cdev;
1034 }
1035
1036 create_units(device);
1037
1038 /*
1039 * Transition the device to running state. If it got pulled
1040 * out from under us while we did the intialization work, we
1041 * have to shut down the device again here. Normally, though,
1042 * fw_node_event will be responsible for shutting it down when
1043 * necessary. We have to use the atomic cmpxchg here to avoid
1044 * racing with the FW_NODE_DESTROYED case in
1045 * fw_node_event().
1046 */
1047 if (atomic_cmpxchg(&device->state,
1048 FW_DEVICE_INITIALIZING,
1049 FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
1050 PREPARE_DELAYED_WORK(&device->work, fw_device_shutdown);
1051 fw_schedule_device_work(device, SHUTDOWN_DELAY);
1052 } else {
1053 fw_notice(card, "created device %s: GUID %08x%08x, S%d00\n",
1054 dev_name(&device->device),
1055 device->config_rom[3], device->config_rom[4],
1056 1 << device->max_speed);
1057 device->config_rom_retries = 0;
1058
1059 set_broadcast_channel(device, device->generation);
1060 }
1061
1062 /*
1063 * Reschedule the IRM work if we just finished reading the
1064 * root node config rom. If this races with a bus reset we
1065 * just end up running the IRM work a couple of extra times -
1066 * pretty harmless.
1067 */
1068 if (device->node == card->root_node)
1069 fw_schedule_bm_work(card, 0);
1070
1071 return;
1072
1073 error_with_cdev:
1074 down_write(&fw_device_rwsem);
1075 idr_remove(&fw_device_idr, minor);
1076 up_write(&fw_device_rwsem);
1077 error:
1078 fw_device_put(device); /* fw_device_idr's reference */
1079
1080 put_device(&device->device); /* our reference */
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 bool *changed)
1086{
1087 u32 q;
1088 int i, rcode;
1089
1090 for (i = 0; i < 6; i++) {
1091 rcode = read_rom(device, generation, i, &q);
1092 if (rcode != RCODE_COMPLETE)
1093 return rcode;
1094
1095 if (i == 0 && q == 0)
1096 /* inaccessible (see read_config_rom); retry later */
1097 return RCODE_BUSY;
1098
1099 if (q != device->config_rom[i]) {
1100 *changed = true;
1101 return RCODE_COMPLETE;
1102 }
1103 }
1104
1105 *changed = false;
1106 return RCODE_COMPLETE;
1107}
1108
1109static void fw_device_refresh(struct work_struct *work)
1110{
1111 struct fw_device *device =
1112 container_of(work, struct fw_device, work.work);
1113 struct fw_card *card = device->card;
1114 int ret, node_id = device->node_id;
1115 bool changed;
1116
1117 ret = reread_config_rom(device, device->generation, &changed);
1118 if (ret != RCODE_COMPLETE)
1119 goto failed_config_rom;
1120
1121 if (!changed) {
1122 if (atomic_cmpxchg(&device->state,
1123 FW_DEVICE_INITIALIZING,
1124 FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
1125 goto gone;
1126
1127 fw_device_update(work);
1128 device->config_rom_retries = 0;
1129 goto out;
1130 }
1131
1132 /*
1133 * Something changed. We keep things simple and don't investigate
1134 * further. We just destroy all previous units and create new ones.
1135 */
1136 device_for_each_child(&device->device, NULL, shutdown_unit);
1137
1138 ret = read_config_rom(device, device->generation);
1139 if (ret != RCODE_COMPLETE)
1140 goto failed_config_rom;
1141
1142 fw_device_cdev_update(device);
1143 create_units(device);
1144
1145 /* Userspace may want to re-read attributes. */
1146 kobject_uevent(&device->device.kobj, KOBJ_CHANGE);
1147
1148 if (atomic_cmpxchg(&device->state,
1149 FW_DEVICE_INITIALIZING,
1150 FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
1151 goto gone;
1152
1153 fw_notice(card, "refreshed device %s\n", dev_name(&device->device));
1154 device->config_rom_retries = 0;
1155 goto out;
1156
1157 failed_config_rom:
1158 if (device->config_rom_retries < MAX_RETRIES &&
1159 atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
1160 device->config_rom_retries++;
1161 fw_schedule_device_work(device, RETRY_DELAY);
1162 return;
1163 }
1164
1165 fw_notice(card, "giving up on refresh of device %s: %s\n",
1166 dev_name(&device->device), fw_rcode_string(ret));
1167 gone:
1168 atomic_set(&device->state, FW_DEVICE_GONE);
1169 PREPARE_DELAYED_WORK(&device->work, fw_device_shutdown);
1170 fw_schedule_device_work(device, SHUTDOWN_DELAY);
1171 out:
1172 if (node_id == card->root_node->node_id)
1173 fw_schedule_bm_work(card, 0);
1174}
1175
1176void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
1177{
1178 struct fw_device *device;
1179
1180 switch (event) {
1181 case FW_NODE_CREATED:
1182 /*
1183 * Attempt to scan the node, regardless whether its self ID has
1184 * the L (link active) flag set or not. Some broken devices
1185 * send L=0 but have an up-and-running link; others send L=1
1186 * without actually having a link.
1187 */
1188 create:
1189 device = kzalloc(sizeof(*device), GFP_ATOMIC);
1190 if (device == NULL)
1191 break;
1192
1193 /*
1194 * Do minimal intialization of the device here, the
1195 * rest will happen in fw_device_init().
1196 *
1197 * Attention: A lot of things, even fw_device_get(),
1198 * cannot be done before fw_device_init() finished!
1199 * You can basically just check device->state and
1200 * schedule work until then, but only while holding
1201 * card->lock.
1202 */
1203 atomic_set(&device->state, FW_DEVICE_INITIALIZING);
1204 device->card = fw_card_get(card);
1205 device->node = fw_node_get(node);
1206 device->node_id = node->node_id;
1207 device->generation = card->generation;
1208 device->is_local = node == card->local_node;
1209 mutex_init(&device->client_list_mutex);
1210 INIT_LIST_HEAD(&device->client_list);
1211
1212 /*
1213 * Set the node data to point back to this device so
1214 * FW_NODE_UPDATED callbacks can update the node_id
1215 * and generation for the device.
1216 */
1217 node->data = device;
1218
1219 /*
1220 * Many devices are slow to respond after bus resets,
1221 * especially if they are bus powered and go through
1222 * power-up after getting plugged in. We schedule the
1223 * first config rom scan half a second after bus reset.
1224 */
1225 INIT_DELAYED_WORK(&device->work, fw_device_init);
1226 fw_schedule_device_work(device, INITIAL_DELAY);
1227 break;
1228
1229 case FW_NODE_INITIATED_RESET:
1230 case FW_NODE_LINK_ON:
1231 device = node->data;
1232 if (device == NULL)
1233 goto create;
1234
1235 device->node_id = node->node_id;
1236 smp_wmb(); /* update node_id before generation */
1237 device->generation = card->generation;
1238 if (atomic_cmpxchg(&device->state,
1239 FW_DEVICE_RUNNING,
1240 FW_DEVICE_INITIALIZING) == FW_DEVICE_RUNNING) {
1241 PREPARE_DELAYED_WORK(&device->work, fw_device_refresh);
1242 fw_schedule_device_work(device,
1243 device->is_local ? 0 : INITIAL_DELAY);
1244 }
1245 break;
1246
1247 case FW_NODE_UPDATED:
1248 device = node->data;
1249 if (device == NULL)
1250 break;
1251
1252 device->node_id = node->node_id;
1253 smp_wmb(); /* update node_id before generation */
1254 device->generation = card->generation;
1255 if (atomic_read(&device->state) == FW_DEVICE_RUNNING) {
1256 PREPARE_DELAYED_WORK(&device->work, fw_device_update);
1257 fw_schedule_device_work(device, 0);
1258 }
1259 break;
1260
1261 case FW_NODE_DESTROYED:
1262 case FW_NODE_LINK_OFF:
1263 if (!node->data)
1264 break;
1265
1266 /*
1267 * Destroy the device associated with the node. There
1268 * are two cases here: either the device is fully
1269 * initialized (FW_DEVICE_RUNNING) or we're in the
1270 * process of reading its config rom
1271 * (FW_DEVICE_INITIALIZING). If it is fully
1272 * initialized we can reuse device->work to schedule a
1273 * full fw_device_shutdown(). If not, there's work
1274 * scheduled to read it's config rom, and we just put
1275 * the device in shutdown state to have that code fail
1276 * to create the device.
1277 */
1278 device = node->data;
1279 if (atomic_xchg(&device->state,
1280 FW_DEVICE_GONE) == FW_DEVICE_RUNNING) {
1281 PREPARE_DELAYED_WORK(&device->work, fw_device_shutdown);
1282 fw_schedule_device_work(device,
1283 list_empty(&card->link) ? 0 : SHUTDOWN_DELAY);
1284 }
1285 break;
1286 }
1287}
1/*
2 * Device probing and sysfs code.
3 *
4 * Copyright (C) 2005-2006 Kristian Hoegsberg <krh@bitplanet.net>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software Foundation,
18 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 */
20
21#include <linux/bug.h>
22#include <linux/ctype.h>
23#include <linux/delay.h>
24#include <linux/device.h>
25#include <linux/errno.h>
26#include <linux/firewire.h>
27#include <linux/firewire-constants.h>
28#include <linux/idr.h>
29#include <linux/jiffies.h>
30#include <linux/kobject.h>
31#include <linux/list.h>
32#include <linux/mod_devicetable.h>
33#include <linux/module.h>
34#include <linux/mutex.h>
35#include <linux/random.h>
36#include <linux/rwsem.h>
37#include <linux/slab.h>
38#include <linux/spinlock.h>
39#include <linux/string.h>
40#include <linux/workqueue.h>
41
42#include <linux/atomic.h>
43#include <asm/byteorder.h>
44
45#include "core.h"
46
47void fw_csr_iterator_init(struct fw_csr_iterator *ci, const u32 *p)
48{
49 ci->p = p + 1;
50 ci->end = ci->p + (p[0] >> 16);
51}
52EXPORT_SYMBOL(fw_csr_iterator_init);
53
54int fw_csr_iterator_next(struct fw_csr_iterator *ci, int *key, int *value)
55{
56 *key = *ci->p >> 24;
57 *value = *ci->p & 0xffffff;
58
59 return ci->p++ < ci->end;
60}
61EXPORT_SYMBOL(fw_csr_iterator_next);
62
63static const u32 *search_leaf(const u32 *directory, int search_key)
64{
65 struct fw_csr_iterator ci;
66 int last_key = 0, key, value;
67
68 fw_csr_iterator_init(&ci, directory);
69 while (fw_csr_iterator_next(&ci, &key, &value)) {
70 if (last_key == search_key &&
71 key == (CSR_DESCRIPTOR | CSR_LEAF))
72 return ci.p - 1 + value;
73
74 last_key = key;
75 }
76
77 return NULL;
78}
79
80static int textual_leaf_to_string(const u32 *block, char *buf, size_t size)
81{
82 unsigned int quadlets, i;
83 char c;
84
85 if (!size || !buf)
86 return -EINVAL;
87
88 quadlets = min(block[0] >> 16, 256U);
89 if (quadlets < 2)
90 return -ENODATA;
91
92 if (block[1] != 0 || block[2] != 0)
93 /* unknown language/character set */
94 return -ENODATA;
95
96 block += 3;
97 quadlets -= 2;
98 for (i = 0; i < quadlets * 4 && i < size - 1; i++) {
99 c = block[i / 4] >> (24 - 8 * (i % 4));
100 if (c == '\0')
101 break;
102 buf[i] = c;
103 }
104 buf[i] = '\0';
105
106 return i;
107}
108
109/**
110 * fw_csr_string() - reads a string from the configuration ROM
111 * @directory: e.g. root directory or unit directory
112 * @key: the key of the preceding directory entry
113 * @buf: where to put the string
114 * @size: size of @buf, in bytes
115 *
116 * The string is taken from a minimal ASCII text descriptor leaf after
117 * the immediate entry with @key. The string is zero-terminated.
118 * An overlong string is silently truncated such that it and the
119 * zero byte fit into @size.
120 *
121 * Returns strlen(buf) or a negative error code.
122 */
123int fw_csr_string(const u32 *directory, int key, char *buf, size_t size)
124{
125 const u32 *leaf = search_leaf(directory, key);
126 if (!leaf)
127 return -ENOENT;
128
129 return textual_leaf_to_string(leaf, buf, size);
130}
131EXPORT_SYMBOL(fw_csr_string);
132
133static void get_ids(const u32 *directory, int *id)
134{
135 struct fw_csr_iterator ci;
136 int key, value;
137
138 fw_csr_iterator_init(&ci, directory);
139 while (fw_csr_iterator_next(&ci, &key, &value)) {
140 switch (key) {
141 case CSR_VENDOR: id[0] = value; break;
142 case CSR_MODEL: id[1] = value; break;
143 case CSR_SPECIFIER_ID: id[2] = value; break;
144 case CSR_VERSION: id[3] = value; break;
145 }
146 }
147}
148
149static void get_modalias_ids(struct fw_unit *unit, int *id)
150{
151 get_ids(&fw_parent_device(unit)->config_rom[5], id);
152 get_ids(unit->directory, id);
153}
154
155static bool match_ids(const struct ieee1394_device_id *id_table, int *id)
156{
157 int match = 0;
158
159 if (id[0] == id_table->vendor_id)
160 match |= IEEE1394_MATCH_VENDOR_ID;
161 if (id[1] == id_table->model_id)
162 match |= IEEE1394_MATCH_MODEL_ID;
163 if (id[2] == id_table->specifier_id)
164 match |= IEEE1394_MATCH_SPECIFIER_ID;
165 if (id[3] == id_table->version)
166 match |= IEEE1394_MATCH_VERSION;
167
168 return (match & id_table->match_flags) == id_table->match_flags;
169}
170
171static const struct ieee1394_device_id *unit_match(struct device *dev,
172 struct device_driver *drv)
173{
174 const struct ieee1394_device_id *id_table =
175 container_of(drv, struct fw_driver, driver)->id_table;
176 int id[] = {0, 0, 0, 0};
177
178 get_modalias_ids(fw_unit(dev), id);
179
180 for (; id_table->match_flags != 0; id_table++)
181 if (match_ids(id_table, id))
182 return id_table;
183
184 return NULL;
185}
186
187static bool is_fw_unit(struct device *dev);
188
189static int fw_unit_match(struct device *dev, struct device_driver *drv)
190{
191 /* We only allow binding to fw_units. */
192 return is_fw_unit(dev) && unit_match(dev, drv) != NULL;
193}
194
195static int fw_unit_probe(struct device *dev)
196{
197 struct fw_driver *driver =
198 container_of(dev->driver, struct fw_driver, driver);
199
200 return driver->probe(fw_unit(dev), unit_match(dev, dev->driver));
201}
202
203static int fw_unit_remove(struct device *dev)
204{
205 struct fw_driver *driver =
206 container_of(dev->driver, struct fw_driver, driver);
207
208 return driver->remove(fw_unit(dev)), 0;
209}
210
211static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
212{
213 int id[] = {0, 0, 0, 0};
214
215 get_modalias_ids(unit, id);
216
217 return snprintf(buffer, buffer_size,
218 "ieee1394:ven%08Xmo%08Xsp%08Xver%08X",
219 id[0], id[1], id[2], id[3]);
220}
221
222static int fw_unit_uevent(struct device *dev, struct kobj_uevent_env *env)
223{
224 struct fw_unit *unit = fw_unit(dev);
225 char modalias[64];
226
227 get_modalias(unit, modalias, sizeof(modalias));
228
229 if (add_uevent_var(env, "MODALIAS=%s", modalias))
230 return -ENOMEM;
231
232 return 0;
233}
234
235struct bus_type fw_bus_type = {
236 .name = "firewire",
237 .match = fw_unit_match,
238 .probe = fw_unit_probe,
239 .remove = fw_unit_remove,
240};
241EXPORT_SYMBOL(fw_bus_type);
242
243int fw_device_enable_phys_dma(struct fw_device *device)
244{
245 int generation = device->generation;
246
247 /* device->node_id, accessed below, must not be older than generation */
248 smp_rmb();
249
250 return device->card->driver->enable_phys_dma(device->card,
251 device->node_id,
252 generation);
253}
254EXPORT_SYMBOL(fw_device_enable_phys_dma);
255
256struct config_rom_attribute {
257 struct device_attribute attr;
258 u32 key;
259};
260
261static ssize_t show_immediate(struct device *dev,
262 struct device_attribute *dattr, char *buf)
263{
264 struct config_rom_attribute *attr =
265 container_of(dattr, struct config_rom_attribute, attr);
266 struct fw_csr_iterator ci;
267 const u32 *dir;
268 int key, value, ret = -ENOENT;
269
270 down_read(&fw_device_rwsem);
271
272 if (is_fw_unit(dev))
273 dir = fw_unit(dev)->directory;
274 else
275 dir = fw_device(dev)->config_rom + 5;
276
277 fw_csr_iterator_init(&ci, dir);
278 while (fw_csr_iterator_next(&ci, &key, &value))
279 if (attr->key == key) {
280 ret = snprintf(buf, buf ? PAGE_SIZE : 0,
281 "0x%06x\n", value);
282 break;
283 }
284
285 up_read(&fw_device_rwsem);
286
287 return ret;
288}
289
290#define IMMEDIATE_ATTR(name, key) \
291 { __ATTR(name, S_IRUGO, show_immediate, NULL), key }
292
293static ssize_t show_text_leaf(struct device *dev,
294 struct device_attribute *dattr, char *buf)
295{
296 struct config_rom_attribute *attr =
297 container_of(dattr, struct config_rom_attribute, attr);
298 const u32 *dir;
299 size_t bufsize;
300 char dummy_buf[2];
301 int ret;
302
303 down_read(&fw_device_rwsem);
304
305 if (is_fw_unit(dev))
306 dir = fw_unit(dev)->directory;
307 else
308 dir = fw_device(dev)->config_rom + 5;
309
310 if (buf) {
311 bufsize = PAGE_SIZE - 1;
312 } else {
313 buf = dummy_buf;
314 bufsize = 1;
315 }
316
317 ret = fw_csr_string(dir, attr->key, buf, bufsize);
318
319 if (ret >= 0) {
320 /* Strip trailing whitespace and add newline. */
321 while (ret > 0 && isspace(buf[ret - 1]))
322 ret--;
323 strcpy(buf + ret, "\n");
324 ret++;
325 }
326
327 up_read(&fw_device_rwsem);
328
329 return ret;
330}
331
332#define TEXT_LEAF_ATTR(name, key) \
333 { __ATTR(name, S_IRUGO, show_text_leaf, NULL), key }
334
335static struct config_rom_attribute config_rom_attributes[] = {
336 IMMEDIATE_ATTR(vendor, CSR_VENDOR),
337 IMMEDIATE_ATTR(hardware_version, CSR_HARDWARE_VERSION),
338 IMMEDIATE_ATTR(specifier_id, CSR_SPECIFIER_ID),
339 IMMEDIATE_ATTR(version, CSR_VERSION),
340 IMMEDIATE_ATTR(model, CSR_MODEL),
341 TEXT_LEAF_ATTR(vendor_name, CSR_VENDOR),
342 TEXT_LEAF_ATTR(model_name, CSR_MODEL),
343 TEXT_LEAF_ATTR(hardware_version_name, CSR_HARDWARE_VERSION),
344};
345
346static void init_fw_attribute_group(struct device *dev,
347 struct device_attribute *attrs,
348 struct fw_attribute_group *group)
349{
350 struct device_attribute *attr;
351 int i, j;
352
353 for (j = 0; attrs[j].attr.name != NULL; j++)
354 group->attrs[j] = &attrs[j].attr;
355
356 for (i = 0; i < ARRAY_SIZE(config_rom_attributes); i++) {
357 attr = &config_rom_attributes[i].attr;
358 if (attr->show(dev, attr, NULL) < 0)
359 continue;
360 group->attrs[j++] = &attr->attr;
361 }
362
363 group->attrs[j] = NULL;
364 group->groups[0] = &group->group;
365 group->groups[1] = NULL;
366 group->group.attrs = group->attrs;
367 dev->groups = (const struct attribute_group **) group->groups;
368}
369
370static ssize_t modalias_show(struct device *dev,
371 struct device_attribute *attr, char *buf)
372{
373 struct fw_unit *unit = fw_unit(dev);
374 int length;
375
376 length = get_modalias(unit, buf, PAGE_SIZE);
377 strcpy(buf + length, "\n");
378
379 return length + 1;
380}
381
382static ssize_t rom_index_show(struct device *dev,
383 struct device_attribute *attr, char *buf)
384{
385 struct fw_device *device = fw_device(dev->parent);
386 struct fw_unit *unit = fw_unit(dev);
387
388 return snprintf(buf, PAGE_SIZE, "%d\n",
389 (int)(unit->directory - device->config_rom));
390}
391
392static struct device_attribute fw_unit_attributes[] = {
393 __ATTR_RO(modalias),
394 __ATTR_RO(rom_index),
395 __ATTR_NULL,
396};
397
398static ssize_t config_rom_show(struct device *dev,
399 struct device_attribute *attr, char *buf)
400{
401 struct fw_device *device = fw_device(dev);
402 size_t length;
403
404 down_read(&fw_device_rwsem);
405 length = device->config_rom_length * 4;
406 memcpy(buf, device->config_rom, length);
407 up_read(&fw_device_rwsem);
408
409 return length;
410}
411
412static ssize_t guid_show(struct device *dev,
413 struct device_attribute *attr, char *buf)
414{
415 struct fw_device *device = fw_device(dev);
416 int ret;
417
418 down_read(&fw_device_rwsem);
419 ret = snprintf(buf, PAGE_SIZE, "0x%08x%08x\n",
420 device->config_rom[3], device->config_rom[4]);
421 up_read(&fw_device_rwsem);
422
423 return ret;
424}
425
426static ssize_t is_local_show(struct device *dev,
427 struct device_attribute *attr, char *buf)
428{
429 struct fw_device *device = fw_device(dev);
430
431 return sprintf(buf, "%u\n", device->is_local);
432}
433
434static int units_sprintf(char *buf, const u32 *directory)
435{
436 struct fw_csr_iterator ci;
437 int key, value;
438 int specifier_id = 0;
439 int version = 0;
440
441 fw_csr_iterator_init(&ci, directory);
442 while (fw_csr_iterator_next(&ci, &key, &value)) {
443 switch (key) {
444 case CSR_SPECIFIER_ID:
445 specifier_id = value;
446 break;
447 case CSR_VERSION:
448 version = value;
449 break;
450 }
451 }
452
453 return sprintf(buf, "0x%06x:0x%06x ", specifier_id, version);
454}
455
456static ssize_t units_show(struct device *dev,
457 struct device_attribute *attr, char *buf)
458{
459 struct fw_device *device = fw_device(dev);
460 struct fw_csr_iterator ci;
461 int key, value, i = 0;
462
463 down_read(&fw_device_rwsem);
464 fw_csr_iterator_init(&ci, &device->config_rom[5]);
465 while (fw_csr_iterator_next(&ci, &key, &value)) {
466 if (key != (CSR_UNIT | CSR_DIRECTORY))
467 continue;
468 i += units_sprintf(&buf[i], ci.p + value - 1);
469 if (i >= PAGE_SIZE - (8 + 1 + 8 + 1))
470 break;
471 }
472 up_read(&fw_device_rwsem);
473
474 if (i)
475 buf[i - 1] = '\n';
476
477 return i;
478}
479
480static struct device_attribute fw_device_attributes[] = {
481 __ATTR_RO(config_rom),
482 __ATTR_RO(guid),
483 __ATTR_RO(is_local),
484 __ATTR_RO(units),
485 __ATTR_NULL,
486};
487
488static int read_rom(struct fw_device *device,
489 int generation, int index, u32 *data)
490{
491 u64 offset = (CSR_REGISTER_BASE | CSR_CONFIG_ROM) + index * 4;
492 int i, rcode;
493
494 /* device->node_id, accessed below, must not be older than generation */
495 smp_rmb();
496
497 for (i = 10; i < 100; i += 10) {
498 rcode = fw_run_transaction(device->card,
499 TCODE_READ_QUADLET_REQUEST, device->node_id,
500 generation, device->max_speed, offset, data, 4);
501 if (rcode != RCODE_BUSY)
502 break;
503 msleep(i);
504 }
505 be32_to_cpus(data);
506
507 return rcode;
508}
509
510#define MAX_CONFIG_ROM_SIZE 256
511
512/*
513 * Read the bus info block, perform a speed probe, and read all of the rest of
514 * the config ROM. We do all this with a cached bus generation. If the bus
515 * generation changes under us, read_config_rom will fail and get retried.
516 * It's better to start all over in this case because the node from which we
517 * are reading the ROM may have changed the ROM during the reset.
518 * Returns either a result code or a negative error code.
519 */
520static int read_config_rom(struct fw_device *device, int generation)
521{
522 struct fw_card *card = device->card;
523 const u32 *old_rom, *new_rom;
524 u32 *rom, *stack;
525 u32 sp, key;
526 int i, end, length, ret;
527
528 rom = kmalloc(sizeof(*rom) * MAX_CONFIG_ROM_SIZE +
529 sizeof(*stack) * MAX_CONFIG_ROM_SIZE, GFP_KERNEL);
530 if (rom == NULL)
531 return -ENOMEM;
532
533 stack = &rom[MAX_CONFIG_ROM_SIZE];
534 memset(rom, 0, sizeof(*rom) * MAX_CONFIG_ROM_SIZE);
535
536 device->max_speed = SCODE_100;
537
538 /* First read the bus info block. */
539 for (i = 0; i < 5; i++) {
540 ret = read_rom(device, generation, i, &rom[i]);
541 if (ret != RCODE_COMPLETE)
542 goto out;
543 /*
544 * As per IEEE1212 7.2, during initialization, devices can
545 * reply with a 0 for the first quadlet of the config
546 * rom to indicate that they are booting (for example,
547 * if the firmware is on the disk of a external
548 * harddisk). In that case we just fail, and the
549 * retry mechanism will try again later.
550 */
551 if (i == 0 && rom[i] == 0) {
552 ret = RCODE_BUSY;
553 goto out;
554 }
555 }
556
557 device->max_speed = device->node->max_speed;
558
559 /*
560 * Determine the speed of
561 * - devices with link speed less than PHY speed,
562 * - devices with 1394b PHY (unless only connected to 1394a PHYs),
563 * - all devices if there are 1394b repeaters.
564 * Note, we cannot use the bus info block's link_spd as starting point
565 * because some buggy firmwares set it lower than necessary and because
566 * 1394-1995 nodes do not have the field.
567 */
568 if ((rom[2] & 0x7) < device->max_speed ||
569 device->max_speed == SCODE_BETA ||
570 card->beta_repeaters_present) {
571 u32 dummy;
572
573 /* for S1600 and S3200 */
574 if (device->max_speed == SCODE_BETA)
575 device->max_speed = card->link_speed;
576
577 while (device->max_speed > SCODE_100) {
578 if (read_rom(device, generation, 0, &dummy) ==
579 RCODE_COMPLETE)
580 break;
581 device->max_speed--;
582 }
583 }
584
585 /*
586 * Now parse the config rom. The config rom is a recursive
587 * directory structure so we parse it using a stack of
588 * references to the blocks that make up the structure. We
589 * push a reference to the root directory on the stack to
590 * start things off.
591 */
592 length = i;
593 sp = 0;
594 stack[sp++] = 0xc0000005;
595 while (sp > 0) {
596 /*
597 * Pop the next block reference of the stack. The
598 * lower 24 bits is the offset into the config rom,
599 * the upper 8 bits are the type of the reference the
600 * block.
601 */
602 key = stack[--sp];
603 i = key & 0xffffff;
604 if (WARN_ON(i >= MAX_CONFIG_ROM_SIZE)) {
605 ret = -ENXIO;
606 goto out;
607 }
608
609 /* Read header quadlet for the block to get the length. */
610 ret = read_rom(device, generation, i, &rom[i]);
611 if (ret != RCODE_COMPLETE)
612 goto out;
613 end = i + (rom[i] >> 16) + 1;
614 if (end > MAX_CONFIG_ROM_SIZE) {
615 /*
616 * This block extends outside the config ROM which is
617 * a firmware bug. Ignore this whole block, i.e.
618 * simply set a fake block length of 0.
619 */
620 fw_err(card, "skipped invalid ROM block %x at %llx\n",
621 rom[i],
622 i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
623 rom[i] = 0;
624 end = i;
625 }
626 i++;
627
628 /*
629 * Now read in the block. If this is a directory
630 * block, check the entries as we read them to see if
631 * it references another block, and push it in that case.
632 */
633 for (; i < end; i++) {
634 ret = read_rom(device, generation, i, &rom[i]);
635 if (ret != RCODE_COMPLETE)
636 goto out;
637
638 if ((key >> 30) != 3 || (rom[i] >> 30) < 2)
639 continue;
640 /*
641 * Offset points outside the ROM. May be a firmware
642 * bug or an Extended ROM entry (IEEE 1212-2001 clause
643 * 7.7.18). Simply overwrite this pointer here by a
644 * fake immediate entry so that later iterators over
645 * the ROM don't have to check offsets all the time.
646 */
647 if (i + (rom[i] & 0xffffff) >= MAX_CONFIG_ROM_SIZE) {
648 fw_err(card,
649 "skipped unsupported ROM entry %x at %llx\n",
650 rom[i],
651 i * 4 | CSR_REGISTER_BASE | CSR_CONFIG_ROM);
652 rom[i] = 0;
653 continue;
654 }
655 stack[sp++] = i + rom[i];
656 }
657 if (length < i)
658 length = i;
659 }
660
661 old_rom = device->config_rom;
662 new_rom = kmemdup(rom, length * 4, GFP_KERNEL);
663 if (new_rom == NULL) {
664 ret = -ENOMEM;
665 goto out;
666 }
667
668 down_write(&fw_device_rwsem);
669 device->config_rom = new_rom;
670 device->config_rom_length = length;
671 up_write(&fw_device_rwsem);
672
673 kfree(old_rom);
674 ret = RCODE_COMPLETE;
675 device->max_rec = rom[2] >> 12 & 0xf;
676 device->cmc = rom[2] >> 30 & 1;
677 device->irmc = rom[2] >> 31 & 1;
678 out:
679 kfree(rom);
680
681 return ret;
682}
683
684static void fw_unit_release(struct device *dev)
685{
686 struct fw_unit *unit = fw_unit(dev);
687
688 fw_device_put(fw_parent_device(unit));
689 kfree(unit);
690}
691
692static struct device_type fw_unit_type = {
693 .uevent = fw_unit_uevent,
694 .release = fw_unit_release,
695};
696
697static bool is_fw_unit(struct device *dev)
698{
699 return dev->type == &fw_unit_type;
700}
701
702static void create_units(struct fw_device *device)
703{
704 struct fw_csr_iterator ci;
705 struct fw_unit *unit;
706 int key, value, i;
707
708 i = 0;
709 fw_csr_iterator_init(&ci, &device->config_rom[5]);
710 while (fw_csr_iterator_next(&ci, &key, &value)) {
711 if (key != (CSR_UNIT | CSR_DIRECTORY))
712 continue;
713
714 /*
715 * Get the address of the unit directory and try to
716 * match the drivers id_tables against it.
717 */
718 unit = kzalloc(sizeof(*unit), GFP_KERNEL);
719 if (unit == NULL)
720 continue;
721
722 unit->directory = ci.p + value - 1;
723 unit->device.bus = &fw_bus_type;
724 unit->device.type = &fw_unit_type;
725 unit->device.parent = &device->device;
726 dev_set_name(&unit->device, "%s.%d", dev_name(&device->device), i++);
727
728 BUILD_BUG_ON(ARRAY_SIZE(unit->attribute_group.attrs) <
729 ARRAY_SIZE(fw_unit_attributes) +
730 ARRAY_SIZE(config_rom_attributes));
731 init_fw_attribute_group(&unit->device,
732 fw_unit_attributes,
733 &unit->attribute_group);
734
735 if (device_register(&unit->device) < 0)
736 goto skip_unit;
737
738 fw_device_get(device);
739 continue;
740
741 skip_unit:
742 kfree(unit);
743 }
744}
745
746static int shutdown_unit(struct device *device, void *data)
747{
748 device_unregister(device);
749
750 return 0;
751}
752
753/*
754 * fw_device_rwsem acts as dual purpose mutex:
755 * - serializes accesses to fw_device_idr,
756 * - serializes accesses to fw_device.config_rom/.config_rom_length and
757 * fw_unit.directory, unless those accesses happen at safe occasions
758 */
759DECLARE_RWSEM(fw_device_rwsem);
760
761DEFINE_IDR(fw_device_idr);
762int fw_cdev_major;
763
764struct fw_device *fw_device_get_by_devt(dev_t devt)
765{
766 struct fw_device *device;
767
768 down_read(&fw_device_rwsem);
769 device = idr_find(&fw_device_idr, MINOR(devt));
770 if (device)
771 fw_device_get(device);
772 up_read(&fw_device_rwsem);
773
774 return device;
775}
776
777struct workqueue_struct *fw_workqueue;
778EXPORT_SYMBOL(fw_workqueue);
779
780static void fw_schedule_device_work(struct fw_device *device,
781 unsigned long delay)
782{
783 queue_delayed_work(fw_workqueue, &device->work, delay);
784}
785
786/*
787 * These defines control the retry behavior for reading the config
788 * rom. It shouldn't be necessary to tweak these; if the device
789 * doesn't respond to a config rom read within 10 seconds, it's not
790 * going to respond at all. As for the initial delay, a lot of
791 * devices will be able to respond within half a second after bus
792 * reset. On the other hand, it's not really worth being more
793 * aggressive than that, since it scales pretty well; if 10 devices
794 * are plugged in, they're all getting read within one second.
795 */
796
797#define MAX_RETRIES 10
798#define RETRY_DELAY (3 * HZ)
799#define INITIAL_DELAY (HZ / 2)
800#define SHUTDOWN_DELAY (2 * HZ)
801
802static void fw_device_shutdown(struct work_struct *work)
803{
804 struct fw_device *device =
805 container_of(work, struct fw_device, work.work);
806 int minor = MINOR(device->device.devt);
807
808 if (time_before64(get_jiffies_64(),
809 device->card->reset_jiffies + SHUTDOWN_DELAY)
810 && !list_empty(&device->card->link)) {
811 fw_schedule_device_work(device, SHUTDOWN_DELAY);
812 return;
813 }
814
815 if (atomic_cmpxchg(&device->state,
816 FW_DEVICE_GONE,
817 FW_DEVICE_SHUTDOWN) != FW_DEVICE_GONE)
818 return;
819
820 fw_device_cdev_remove(device);
821 device_for_each_child(&device->device, NULL, shutdown_unit);
822 device_unregister(&device->device);
823
824 down_write(&fw_device_rwsem);
825 idr_remove(&fw_device_idr, minor);
826 up_write(&fw_device_rwsem);
827
828 fw_device_put(device);
829}
830
831static void fw_device_release(struct device *dev)
832{
833 struct fw_device *device = fw_device(dev);
834 struct fw_card *card = device->card;
835 unsigned long flags;
836
837 /*
838 * Take the card lock so we don't set this to NULL while a
839 * FW_NODE_UPDATED callback is being handled or while the
840 * bus manager work looks at this node.
841 */
842 spin_lock_irqsave(&card->lock, flags);
843 device->node->data = NULL;
844 spin_unlock_irqrestore(&card->lock, flags);
845
846 fw_node_put(device->node);
847 kfree(device->config_rom);
848 kfree(device);
849 fw_card_put(card);
850}
851
852static struct device_type fw_device_type = {
853 .release = fw_device_release,
854};
855
856static bool is_fw_device(struct device *dev)
857{
858 return dev->type == &fw_device_type;
859}
860
861static int update_unit(struct device *dev, void *data)
862{
863 struct fw_unit *unit = fw_unit(dev);
864 struct fw_driver *driver = (struct fw_driver *)dev->driver;
865
866 if (is_fw_unit(dev) && driver != NULL && driver->update != NULL) {
867 device_lock(dev);
868 driver->update(unit);
869 device_unlock(dev);
870 }
871
872 return 0;
873}
874
875static void fw_device_update(struct work_struct *work)
876{
877 struct fw_device *device =
878 container_of(work, struct fw_device, work.work);
879
880 fw_device_cdev_update(device);
881 device_for_each_child(&device->device, NULL, update_unit);
882}
883
884/*
885 * If a device was pending for deletion because its node went away but its
886 * bus info block and root directory header matches that of a newly discovered
887 * device, revive the existing fw_device.
888 * The newly allocated fw_device becomes obsolete instead.
889 */
890static int lookup_existing_device(struct device *dev, void *data)
891{
892 struct fw_device *old = fw_device(dev);
893 struct fw_device *new = data;
894 struct fw_card *card = new->card;
895 int match = 0;
896
897 if (!is_fw_device(dev))
898 return 0;
899
900 down_read(&fw_device_rwsem); /* serialize config_rom access */
901 spin_lock_irq(&card->lock); /* serialize node access */
902
903 if (memcmp(old->config_rom, new->config_rom, 6 * 4) == 0 &&
904 atomic_cmpxchg(&old->state,
905 FW_DEVICE_GONE,
906 FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
907 struct fw_node *current_node = new->node;
908 struct fw_node *obsolete_node = old->node;
909
910 new->node = obsolete_node;
911 new->node->data = new;
912 old->node = current_node;
913 old->node->data = old;
914
915 old->max_speed = new->max_speed;
916 old->node_id = current_node->node_id;
917 smp_wmb(); /* update node_id before generation */
918 old->generation = card->generation;
919 old->config_rom_retries = 0;
920 fw_notice(card, "rediscovered device %s\n", dev_name(dev));
921
922 old->workfn = fw_device_update;
923 fw_schedule_device_work(old, 0);
924
925 if (current_node == card->root_node)
926 fw_schedule_bm_work(card, 0);
927
928 match = 1;
929 }
930
931 spin_unlock_irq(&card->lock);
932 up_read(&fw_device_rwsem);
933
934 return match;
935}
936
937enum { BC_UNKNOWN = 0, BC_UNIMPLEMENTED, BC_IMPLEMENTED, };
938
939static void set_broadcast_channel(struct fw_device *device, int generation)
940{
941 struct fw_card *card = device->card;
942 __be32 data;
943 int rcode;
944
945 if (!card->broadcast_channel_allocated)
946 return;
947
948 /*
949 * The Broadcast_Channel Valid bit is required by nodes which want to
950 * transmit on this channel. Such transmissions are practically
951 * exclusive to IP over 1394 (RFC 2734). IP capable nodes are required
952 * to be IRM capable and have a max_rec of 8 or more. We use this fact
953 * to narrow down to which nodes we send Broadcast_Channel updates.
954 */
955 if (!device->irmc || device->max_rec < 8)
956 return;
957
958 /*
959 * Some 1394-1995 nodes crash if this 1394a-2000 register is written.
960 * Perform a read test first.
961 */
962 if (device->bc_implemented == BC_UNKNOWN) {
963 rcode = fw_run_transaction(card, TCODE_READ_QUADLET_REQUEST,
964 device->node_id, generation, device->max_speed,
965 CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
966 &data, 4);
967 switch (rcode) {
968 case RCODE_COMPLETE:
969 if (data & cpu_to_be32(1 << 31)) {
970 device->bc_implemented = BC_IMPLEMENTED;
971 break;
972 }
973 /* else fall through to case address error */
974 case RCODE_ADDRESS_ERROR:
975 device->bc_implemented = BC_UNIMPLEMENTED;
976 }
977 }
978
979 if (device->bc_implemented == BC_IMPLEMENTED) {
980 data = cpu_to_be32(BROADCAST_CHANNEL_INITIAL |
981 BROADCAST_CHANNEL_VALID);
982 fw_run_transaction(card, TCODE_WRITE_QUADLET_REQUEST,
983 device->node_id, generation, device->max_speed,
984 CSR_REGISTER_BASE + CSR_BROADCAST_CHANNEL,
985 &data, 4);
986 }
987}
988
989int fw_device_set_broadcast_channel(struct device *dev, void *gen)
990{
991 if (is_fw_device(dev))
992 set_broadcast_channel(fw_device(dev), (long)gen);
993
994 return 0;
995}
996
997static void fw_device_init(struct work_struct *work)
998{
999 struct fw_device *device =
1000 container_of(work, struct fw_device, work.work);
1001 struct fw_card *card = device->card;
1002 struct device *revived_dev;
1003 int minor, ret;
1004
1005 /*
1006 * All failure paths here set node->data to NULL, so that we
1007 * don't try to do device_for_each_child() on a kfree()'d
1008 * device.
1009 */
1010
1011 ret = read_config_rom(device, device->generation);
1012 if (ret != RCODE_COMPLETE) {
1013 if (device->config_rom_retries < MAX_RETRIES &&
1014 atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
1015 device->config_rom_retries++;
1016 fw_schedule_device_work(device, RETRY_DELAY);
1017 } else {
1018 if (device->node->link_on)
1019 fw_notice(card, "giving up on node %x: reading config rom failed: %s\n",
1020 device->node_id,
1021 fw_rcode_string(ret));
1022 if (device->node == card->root_node)
1023 fw_schedule_bm_work(card, 0);
1024 fw_device_release(&device->device);
1025 }
1026 return;
1027 }
1028
1029 revived_dev = device_find_child(card->device,
1030 device, lookup_existing_device);
1031 if (revived_dev) {
1032 put_device(revived_dev);
1033 fw_device_release(&device->device);
1034
1035 return;
1036 }
1037
1038 device_initialize(&device->device);
1039
1040 fw_device_get(device);
1041 down_write(&fw_device_rwsem);
1042 minor = idr_alloc(&fw_device_idr, device, 0, 1 << MINORBITS,
1043 GFP_KERNEL);
1044 up_write(&fw_device_rwsem);
1045
1046 if (minor < 0)
1047 goto error;
1048
1049 device->device.bus = &fw_bus_type;
1050 device->device.type = &fw_device_type;
1051 device->device.parent = card->device;
1052 device->device.devt = MKDEV(fw_cdev_major, minor);
1053 dev_set_name(&device->device, "fw%d", minor);
1054
1055 BUILD_BUG_ON(ARRAY_SIZE(device->attribute_group.attrs) <
1056 ARRAY_SIZE(fw_device_attributes) +
1057 ARRAY_SIZE(config_rom_attributes));
1058 init_fw_attribute_group(&device->device,
1059 fw_device_attributes,
1060 &device->attribute_group);
1061
1062 if (device_add(&device->device)) {
1063 fw_err(card, "failed to add device\n");
1064 goto error_with_cdev;
1065 }
1066
1067 create_units(device);
1068
1069 /*
1070 * Transition the device to running state. If it got pulled
1071 * out from under us while we did the initialization work, we
1072 * have to shut down the device again here. Normally, though,
1073 * fw_node_event will be responsible for shutting it down when
1074 * necessary. We have to use the atomic cmpxchg here to avoid
1075 * racing with the FW_NODE_DESTROYED case in
1076 * fw_node_event().
1077 */
1078 if (atomic_cmpxchg(&device->state,
1079 FW_DEVICE_INITIALIZING,
1080 FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
1081 device->workfn = fw_device_shutdown;
1082 fw_schedule_device_work(device, SHUTDOWN_DELAY);
1083 } else {
1084 fw_notice(card, "created device %s: GUID %08x%08x, S%d00\n",
1085 dev_name(&device->device),
1086 device->config_rom[3], device->config_rom[4],
1087 1 << device->max_speed);
1088 device->config_rom_retries = 0;
1089
1090 set_broadcast_channel(device, device->generation);
1091
1092 add_device_randomness(&device->config_rom[3], 8);
1093 }
1094
1095 /*
1096 * Reschedule the IRM work if we just finished reading the
1097 * root node config rom. If this races with a bus reset we
1098 * just end up running the IRM work a couple of extra times -
1099 * pretty harmless.
1100 */
1101 if (device->node == card->root_node)
1102 fw_schedule_bm_work(card, 0);
1103
1104 return;
1105
1106 error_with_cdev:
1107 down_write(&fw_device_rwsem);
1108 idr_remove(&fw_device_idr, minor);
1109 up_write(&fw_device_rwsem);
1110 error:
1111 fw_device_put(device); /* fw_device_idr's reference */
1112
1113 put_device(&device->device); /* our reference */
1114}
1115
1116/* Reread and compare bus info block and header of root directory */
1117static int reread_config_rom(struct fw_device *device, int generation,
1118 bool *changed)
1119{
1120 u32 q;
1121 int i, rcode;
1122
1123 for (i = 0; i < 6; i++) {
1124 rcode = read_rom(device, generation, i, &q);
1125 if (rcode != RCODE_COMPLETE)
1126 return rcode;
1127
1128 if (i == 0 && q == 0)
1129 /* inaccessible (see read_config_rom); retry later */
1130 return RCODE_BUSY;
1131
1132 if (q != device->config_rom[i]) {
1133 *changed = true;
1134 return RCODE_COMPLETE;
1135 }
1136 }
1137
1138 *changed = false;
1139 return RCODE_COMPLETE;
1140}
1141
1142static void fw_device_refresh(struct work_struct *work)
1143{
1144 struct fw_device *device =
1145 container_of(work, struct fw_device, work.work);
1146 struct fw_card *card = device->card;
1147 int ret, node_id = device->node_id;
1148 bool changed;
1149
1150 ret = reread_config_rom(device, device->generation, &changed);
1151 if (ret != RCODE_COMPLETE)
1152 goto failed_config_rom;
1153
1154 if (!changed) {
1155 if (atomic_cmpxchg(&device->state,
1156 FW_DEVICE_INITIALIZING,
1157 FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
1158 goto gone;
1159
1160 fw_device_update(work);
1161 device->config_rom_retries = 0;
1162 goto out;
1163 }
1164
1165 /*
1166 * Something changed. We keep things simple and don't investigate
1167 * further. We just destroy all previous units and create new ones.
1168 */
1169 device_for_each_child(&device->device, NULL, shutdown_unit);
1170
1171 ret = read_config_rom(device, device->generation);
1172 if (ret != RCODE_COMPLETE)
1173 goto failed_config_rom;
1174
1175 fw_device_cdev_update(device);
1176 create_units(device);
1177
1178 /* Userspace may want to re-read attributes. */
1179 kobject_uevent(&device->device.kobj, KOBJ_CHANGE);
1180
1181 if (atomic_cmpxchg(&device->state,
1182 FW_DEVICE_INITIALIZING,
1183 FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
1184 goto gone;
1185
1186 fw_notice(card, "refreshed device %s\n", dev_name(&device->device));
1187 device->config_rom_retries = 0;
1188 goto out;
1189
1190 failed_config_rom:
1191 if (device->config_rom_retries < MAX_RETRIES &&
1192 atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
1193 device->config_rom_retries++;
1194 fw_schedule_device_work(device, RETRY_DELAY);
1195 return;
1196 }
1197
1198 fw_notice(card, "giving up on refresh of device %s: %s\n",
1199 dev_name(&device->device), fw_rcode_string(ret));
1200 gone:
1201 atomic_set(&device->state, FW_DEVICE_GONE);
1202 device->workfn = fw_device_shutdown;
1203 fw_schedule_device_work(device, SHUTDOWN_DELAY);
1204 out:
1205 if (node_id == card->root_node->node_id)
1206 fw_schedule_bm_work(card, 0);
1207}
1208
1209static void fw_device_workfn(struct work_struct *work)
1210{
1211 struct fw_device *device = container_of(to_delayed_work(work),
1212 struct fw_device, work);
1213 device->workfn(work);
1214}
1215
1216void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
1217{
1218 struct fw_device *device;
1219
1220 switch (event) {
1221 case FW_NODE_CREATED:
1222 /*
1223 * Attempt to scan the node, regardless whether its self ID has
1224 * the L (link active) flag set or not. Some broken devices
1225 * send L=0 but have an up-and-running link; others send L=1
1226 * without actually having a link.
1227 */
1228 create:
1229 device = kzalloc(sizeof(*device), GFP_ATOMIC);
1230 if (device == NULL)
1231 break;
1232
1233 /*
1234 * Do minimal initialization of the device here, the
1235 * rest will happen in fw_device_init().
1236 *
1237 * Attention: A lot of things, even fw_device_get(),
1238 * cannot be done before fw_device_init() finished!
1239 * You can basically just check device->state and
1240 * schedule work until then, but only while holding
1241 * card->lock.
1242 */
1243 atomic_set(&device->state, FW_DEVICE_INITIALIZING);
1244 device->card = fw_card_get(card);
1245 device->node = fw_node_get(node);
1246 device->node_id = node->node_id;
1247 device->generation = card->generation;
1248 device->is_local = node == card->local_node;
1249 mutex_init(&device->client_list_mutex);
1250 INIT_LIST_HEAD(&device->client_list);
1251
1252 /*
1253 * Set the node data to point back to this device so
1254 * FW_NODE_UPDATED callbacks can update the node_id
1255 * and generation for the device.
1256 */
1257 node->data = device;
1258
1259 /*
1260 * Many devices are slow to respond after bus resets,
1261 * especially if they are bus powered and go through
1262 * power-up after getting plugged in. We schedule the
1263 * first config rom scan half a second after bus reset.
1264 */
1265 device->workfn = fw_device_init;
1266 INIT_DELAYED_WORK(&device->work, fw_device_workfn);
1267 fw_schedule_device_work(device, INITIAL_DELAY);
1268 break;
1269
1270 case FW_NODE_INITIATED_RESET:
1271 case FW_NODE_LINK_ON:
1272 device = node->data;
1273 if (device == NULL)
1274 goto create;
1275
1276 device->node_id = node->node_id;
1277 smp_wmb(); /* update node_id before generation */
1278 device->generation = card->generation;
1279 if (atomic_cmpxchg(&device->state,
1280 FW_DEVICE_RUNNING,
1281 FW_DEVICE_INITIALIZING) == FW_DEVICE_RUNNING) {
1282 device->workfn = fw_device_refresh;
1283 fw_schedule_device_work(device,
1284 device->is_local ? 0 : INITIAL_DELAY);
1285 }
1286 break;
1287
1288 case FW_NODE_UPDATED:
1289 device = node->data;
1290 if (device == NULL)
1291 break;
1292
1293 device->node_id = node->node_id;
1294 smp_wmb(); /* update node_id before generation */
1295 device->generation = card->generation;
1296 if (atomic_read(&device->state) == FW_DEVICE_RUNNING) {
1297 device->workfn = fw_device_update;
1298 fw_schedule_device_work(device, 0);
1299 }
1300 break;
1301
1302 case FW_NODE_DESTROYED:
1303 case FW_NODE_LINK_OFF:
1304 if (!node->data)
1305 break;
1306
1307 /*
1308 * Destroy the device associated with the node. There
1309 * are two cases here: either the device is fully
1310 * initialized (FW_DEVICE_RUNNING) or we're in the
1311 * process of reading its config rom
1312 * (FW_DEVICE_INITIALIZING). If it is fully
1313 * initialized we can reuse device->work to schedule a
1314 * full fw_device_shutdown(). If not, there's work
1315 * scheduled to read it's config rom, and we just put
1316 * the device in shutdown state to have that code fail
1317 * to create the device.
1318 */
1319 device = node->data;
1320 if (atomic_xchg(&device->state,
1321 FW_DEVICE_GONE) == FW_DEVICE_RUNNING) {
1322 device->workfn = fw_device_shutdown;
1323 fw_schedule_device_work(device,
1324 list_empty(&card->link) ? 0 : SHUTDOWN_DELAY);
1325 }
1326 break;
1327 }
1328}