1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Device probing and sysfs code.
5 * Copyright (C) 2005-2006 Kristian Hoegsberg <krh@bitplanet.net>
9 #include <linux/ctype.h>
10 #include <linux/delay.h>
11 #include <linux/device.h>
12 #include <linux/errno.h>
13 #include <linux/firewire.h>
14 #include <linux/firewire-constants.h>
15 #include <linux/idr.h>
16 #include <linux/jiffies.h>
17 #include <linux/kobject.h>
18 #include <linux/list.h>
19 #include <linux/mod_devicetable.h>
20 #include <linux/module.h>
21 #include <linux/mutex.h>
22 #include <linux/random.h>
23 #include <linux/rwsem.h>
24 #include <linux/slab.h>
25 #include <linux/spinlock.h>
26 #include <linux/string.h>
27 #include <linux/workqueue.h>
29 #include <linux/atomic.h>
30 #include <asm/byteorder.h>
34 void fw_csr_iterator_init(struct fw_csr_iterator
*ci
, const u32
*p
)
37 ci
->end
= ci
->p
+ (p
[0] >> 16);
39 EXPORT_SYMBOL(fw_csr_iterator_init
);
41 int fw_csr_iterator_next(struct fw_csr_iterator
*ci
, int *key
, int *value
)
44 *value
= *ci
->p
& 0xffffff;
46 return ci
->p
++ < ci
->end
;
48 EXPORT_SYMBOL(fw_csr_iterator_next
);
50 static const u32
*search_leaf(const u32
*directory
, int search_key
)
52 struct fw_csr_iterator ci
;
53 int last_key
= 0, key
, value
;
55 fw_csr_iterator_init(&ci
, directory
);
56 while (fw_csr_iterator_next(&ci
, &key
, &value
)) {
57 if (last_key
== search_key
&&
58 key
== (CSR_DESCRIPTOR
| CSR_LEAF
))
59 return ci
.p
- 1 + value
;
67 static int textual_leaf_to_string(const u32
*block
, char *buf
, size_t size
)
69 unsigned int quadlets
, i
;
75 quadlets
= min(block
[0] >> 16, 256U);
79 if (block
[1] != 0 || block
[2] != 0)
80 /* unknown language/character set */
85 for (i
= 0; i
< quadlets
* 4 && i
< size
- 1; i
++) {
86 c
= block
[i
/ 4] >> (24 - 8 * (i
% 4));
97 * fw_csr_string() - reads a string from the configuration ROM
98 * @directory: e.g. root directory or unit directory
99 * @key: the key of the preceding directory entry
100 * @buf: where to put the string
101 * @size: size of @buf, in bytes
103 * The string is taken from a minimal ASCII text descriptor leaf after
104 * the immediate entry with @key. The string is zero-terminated.
105 * An overlong string is silently truncated such that it and the
106 * zero byte fit into @size.
108 * Returns strlen(buf) or a negative error code.
110 int fw_csr_string(const u32
*directory
, int key
, char *buf
, size_t size
)
112 const u32
*leaf
= search_leaf(directory
, key
);
116 return textual_leaf_to_string(leaf
, buf
, size
);
118 EXPORT_SYMBOL(fw_csr_string
);
120 static void get_ids(const u32
*directory
, int *id
)
122 struct fw_csr_iterator ci
;
125 fw_csr_iterator_init(&ci
, directory
);
126 while (fw_csr_iterator_next(&ci
, &key
, &value
)) {
128 case CSR_VENDOR
: id
[0] = value
; break;
129 case CSR_MODEL
: id
[1] = value
; break;
130 case CSR_SPECIFIER_ID
: id
[2] = value
; break;
131 case CSR_VERSION
: id
[3] = value
; break;
136 static void get_modalias_ids(const struct fw_unit
*unit
, int *id
)
138 get_ids(&fw_parent_device(unit
)->config_rom
[5], id
);
139 get_ids(unit
->directory
, id
);
142 static bool match_ids(const struct ieee1394_device_id
*id_table
, int *id
)
146 if (id
[0] == id_table
->vendor_id
)
147 match
|= IEEE1394_MATCH_VENDOR_ID
;
148 if (id
[1] == id_table
->model_id
)
149 match
|= IEEE1394_MATCH_MODEL_ID
;
150 if (id
[2] == id_table
->specifier_id
)
151 match
|= IEEE1394_MATCH_SPECIFIER_ID
;
152 if (id
[3] == id_table
->version
)
153 match
|= IEEE1394_MATCH_VERSION
;
155 return (match
& id_table
->match_flags
) == id_table
->match_flags
;
158 static const struct ieee1394_device_id
*unit_match(struct device
*dev
,
159 struct device_driver
*drv
)
161 const struct ieee1394_device_id
*id_table
=
162 container_of(drv
, struct fw_driver
, driver
)->id_table
;
163 int id
[] = {0, 0, 0, 0};
165 get_modalias_ids(fw_unit(dev
), id
);
167 for (; id_table
->match_flags
!= 0; id_table
++)
168 if (match_ids(id_table
, id
))
174 static bool is_fw_unit(struct device
*dev
);
176 static int fw_unit_match(struct device
*dev
, struct device_driver
*drv
)
178 /* We only allow binding to fw_units. */
179 return is_fw_unit(dev
) && unit_match(dev
, drv
) != NULL
;
182 static int fw_unit_probe(struct device
*dev
)
184 struct fw_driver
*driver
=
185 container_of(dev
->driver
, struct fw_driver
, driver
);
187 return driver
->probe(fw_unit(dev
), unit_match(dev
, dev
->driver
));
190 static void fw_unit_remove(struct device
*dev
)
192 struct fw_driver
*driver
=
193 container_of(dev
->driver
, struct fw_driver
, driver
);
195 driver
->remove(fw_unit(dev
));
198 static int get_modalias(const struct fw_unit
*unit
, char *buffer
, size_t buffer_size
)
200 int id
[] = {0, 0, 0, 0};
202 get_modalias_ids(unit
, id
);
204 return snprintf(buffer
, buffer_size
,
205 "ieee1394:ven%08Xmo%08Xsp%08Xver%08X",
206 id
[0], id
[1], id
[2], id
[3]);
209 static int fw_unit_uevent(const struct device
*dev
, struct kobj_uevent_env
*env
)
211 const struct fw_unit
*unit
= fw_unit(dev
);
214 get_modalias(unit
, modalias
, sizeof(modalias
));
216 if (add_uevent_var(env
, "MODALIAS=%s", modalias
))
222 struct bus_type fw_bus_type
= {
224 .match
= fw_unit_match
,
225 .probe
= fw_unit_probe
,
226 .remove
= fw_unit_remove
,
228 EXPORT_SYMBOL(fw_bus_type
);
230 int fw_device_enable_phys_dma(struct fw_device
*device
)
232 int generation
= device
->generation
;
234 /* device->node_id, accessed below, must not be older than generation */
237 return device
->card
->driver
->enable_phys_dma(device
->card
,
241 EXPORT_SYMBOL(fw_device_enable_phys_dma
);
243 struct config_rom_attribute
{
244 struct device_attribute attr
;
248 static ssize_t
show_immediate(struct device
*dev
,
249 struct device_attribute
*dattr
, char *buf
)
251 struct config_rom_attribute
*attr
=
252 container_of(dattr
, struct config_rom_attribute
, attr
);
253 struct fw_csr_iterator ci
;
255 int key
, value
, ret
= -ENOENT
;
257 down_read(&fw_device_rwsem
);
260 dir
= fw_unit(dev
)->directory
;
262 dir
= fw_device(dev
)->config_rom
+ 5;
264 fw_csr_iterator_init(&ci
, dir
);
265 while (fw_csr_iterator_next(&ci
, &key
, &value
))
266 if (attr
->key
== key
) {
267 ret
= snprintf(buf
, buf
? PAGE_SIZE
: 0,
272 up_read(&fw_device_rwsem
);
277 #define IMMEDIATE_ATTR(name, key) \
278 { __ATTR(name, S_IRUGO, show_immediate, NULL), key }
280 static ssize_t
show_text_leaf(struct device
*dev
,
281 struct device_attribute
*dattr
, char *buf
)
283 struct config_rom_attribute
*attr
=
284 container_of(dattr
, struct config_rom_attribute
, attr
);
290 down_read(&fw_device_rwsem
);
293 dir
= fw_unit(dev
)->directory
;
295 dir
= fw_device(dev
)->config_rom
+ 5;
298 bufsize
= PAGE_SIZE
- 1;
304 ret
= fw_csr_string(dir
, attr
->key
, buf
, bufsize
);
307 /* Strip trailing whitespace and add newline. */
308 while (ret
> 0 && isspace(buf
[ret
- 1]))
310 strcpy(buf
+ ret
, "\n");
314 up_read(&fw_device_rwsem
);
319 #define TEXT_LEAF_ATTR(name, key) \
320 { __ATTR(name, S_IRUGO, show_text_leaf, NULL), key }
322 static struct config_rom_attribute config_rom_attributes
[] = {
323 IMMEDIATE_ATTR(vendor
, CSR_VENDOR
),
324 IMMEDIATE_ATTR(hardware_version
, CSR_HARDWARE_VERSION
),
325 IMMEDIATE_ATTR(specifier_id
, CSR_SPECIFIER_ID
),
326 IMMEDIATE_ATTR(version
, CSR_VERSION
),
327 IMMEDIATE_ATTR(model
, CSR_MODEL
),
328 TEXT_LEAF_ATTR(vendor_name
, CSR_VENDOR
),
329 TEXT_LEAF_ATTR(model_name
, CSR_MODEL
),
330 TEXT_LEAF_ATTR(hardware_version_name
, CSR_HARDWARE_VERSION
),
333 static void init_fw_attribute_group(struct device
*dev
,
334 struct device_attribute
*attrs
,
335 struct fw_attribute_group
*group
)
337 struct device_attribute
*attr
;
340 for (j
= 0; attrs
[j
].attr
.name
!= NULL
; j
++)
341 group
->attrs
[j
] = &attrs
[j
].attr
;
343 for (i
= 0; i
< ARRAY_SIZE(config_rom_attributes
); i
++) {
344 attr
= &config_rom_attributes
[i
].attr
;
345 if (attr
->show(dev
, attr
, NULL
) < 0)
347 group
->attrs
[j
++] = &attr
->attr
;
350 group
->attrs
[j
] = NULL
;
351 group
->groups
[0] = &group
->group
;
352 group
->groups
[1] = NULL
;
353 group
->group
.attrs
= group
->attrs
;
354 dev
->groups
= (const struct attribute_group
**) group
->groups
;
357 static ssize_t
modalias_show(struct device
*dev
,
358 struct device_attribute
*attr
, char *buf
)
360 struct fw_unit
*unit
= fw_unit(dev
);
363 length
= get_modalias(unit
, buf
, PAGE_SIZE
);
364 strcpy(buf
+ length
, "\n");
369 static ssize_t
rom_index_show(struct device
*dev
,
370 struct device_attribute
*attr
, char *buf
)
372 struct fw_device
*device
= fw_device(dev
->parent
);
373 struct fw_unit
*unit
= fw_unit(dev
);
375 return sysfs_emit(buf
, "%td\n", unit
->directory
- device
->config_rom
);
378 static struct device_attribute fw_unit_attributes
[] = {
380 __ATTR_RO(rom_index
),
384 static ssize_t
config_rom_show(struct device
*dev
,
385 struct device_attribute
*attr
, char *buf
)
387 struct fw_device
*device
= fw_device(dev
);
390 down_read(&fw_device_rwsem
);
391 length
= device
->config_rom_length
* 4;
392 memcpy(buf
, device
->config_rom
, length
);
393 up_read(&fw_device_rwsem
);
398 static ssize_t
guid_show(struct device
*dev
,
399 struct device_attribute
*attr
, char *buf
)
401 struct fw_device
*device
= fw_device(dev
);
404 down_read(&fw_device_rwsem
);
405 ret
= sysfs_emit(buf
, "0x%08x%08x\n", device
->config_rom
[3], device
->config_rom
[4]);
406 up_read(&fw_device_rwsem
);
411 static ssize_t
is_local_show(struct device
*dev
,
412 struct device_attribute
*attr
, char *buf
)
414 struct fw_device
*device
= fw_device(dev
);
416 return sprintf(buf
, "%u\n", device
->is_local
);
419 static int units_sprintf(char *buf
, const u32
*directory
)
421 struct fw_csr_iterator ci
;
423 int specifier_id
= 0;
426 fw_csr_iterator_init(&ci
, directory
);
427 while (fw_csr_iterator_next(&ci
, &key
, &value
)) {
429 case CSR_SPECIFIER_ID
:
430 specifier_id
= value
;
438 return sprintf(buf
, "0x%06x:0x%06x ", specifier_id
, version
);
441 static ssize_t
units_show(struct device
*dev
,
442 struct device_attribute
*attr
, char *buf
)
444 struct fw_device
*device
= fw_device(dev
);
445 struct fw_csr_iterator ci
;
446 int key
, value
, i
= 0;
448 down_read(&fw_device_rwsem
);
449 fw_csr_iterator_init(&ci
, &device
->config_rom
[5]);
450 while (fw_csr_iterator_next(&ci
, &key
, &value
)) {
451 if (key
!= (CSR_UNIT
| CSR_DIRECTORY
))
453 i
+= units_sprintf(&buf
[i
], ci
.p
+ value
- 1);
454 if (i
>= PAGE_SIZE
- (8 + 1 + 8 + 1))
457 up_read(&fw_device_rwsem
);
465 static struct device_attribute fw_device_attributes
[] = {
466 __ATTR_RO(config_rom
),
473 static int read_rom(struct fw_device
*device
,
474 int generation
, int index
, u32
*data
)
476 u64 offset
= (CSR_REGISTER_BASE
| CSR_CONFIG_ROM
) + index
* 4;
479 /* device->node_id, accessed below, must not be older than generation */
482 for (i
= 10; i
< 100; i
+= 10) {
483 rcode
= fw_run_transaction(device
->card
,
484 TCODE_READ_QUADLET_REQUEST
, device
->node_id
,
485 generation
, device
->max_speed
, offset
, data
, 4);
486 if (rcode
!= RCODE_BUSY
)
495 #define MAX_CONFIG_ROM_SIZE 256
498 * Read the bus info block, perform a speed probe, and read all of the rest of
499 * the config ROM. We do all this with a cached bus generation. If the bus
500 * generation changes under us, read_config_rom will fail and get retried.
501 * It's better to start all over in this case because the node from which we
502 * are reading the ROM may have changed the ROM during the reset.
503 * Returns either a result code or a negative error code.
505 static int read_config_rom(struct fw_device
*device
, int generation
)
507 struct fw_card
*card
= device
->card
;
508 const u32
*old_rom
, *new_rom
;
511 int i
, end
, length
, ret
;
513 rom
= kmalloc(sizeof(*rom
) * MAX_CONFIG_ROM_SIZE
+
514 sizeof(*stack
) * MAX_CONFIG_ROM_SIZE
, GFP_KERNEL
);
518 stack
= &rom
[MAX_CONFIG_ROM_SIZE
];
519 memset(rom
, 0, sizeof(*rom
) * MAX_CONFIG_ROM_SIZE
);
521 device
->max_speed
= SCODE_100
;
523 /* First read the bus info block. */
524 for (i
= 0; i
< 5; i
++) {
525 ret
= read_rom(device
, generation
, i
, &rom
[i
]);
526 if (ret
!= RCODE_COMPLETE
)
529 * As per IEEE1212 7.2, during initialization, devices can
530 * reply with a 0 for the first quadlet of the config
531 * rom to indicate that they are booting (for example,
532 * if the firmware is on the disk of a external
533 * harddisk). In that case we just fail, and the
534 * retry mechanism will try again later.
536 if (i
== 0 && rom
[i
] == 0) {
542 device
->max_speed
= device
->node
->max_speed
;
545 * Determine the speed of
546 * - devices with link speed less than PHY speed,
547 * - devices with 1394b PHY (unless only connected to 1394a PHYs),
548 * - all devices if there are 1394b repeaters.
549 * Note, we cannot use the bus info block's link_spd as starting point
550 * because some buggy firmwares set it lower than necessary and because
551 * 1394-1995 nodes do not have the field.
553 if ((rom
[2] & 0x7) < device
->max_speed
||
554 device
->max_speed
== SCODE_BETA
||
555 card
->beta_repeaters_present
) {
558 /* for S1600 and S3200 */
559 if (device
->max_speed
== SCODE_BETA
)
560 device
->max_speed
= card
->link_speed
;
562 while (device
->max_speed
> SCODE_100
) {
563 if (read_rom(device
, generation
, 0, &dummy
) ==
571 * Now parse the config rom. The config rom is a recursive
572 * directory structure so we parse it using a stack of
573 * references to the blocks that make up the structure. We
574 * push a reference to the root directory on the stack to
579 stack
[sp
++] = 0xc0000005;
582 * Pop the next block reference of the stack. The
583 * lower 24 bits is the offset into the config rom,
584 * the upper 8 bits are the type of the reference the
589 if (WARN_ON(i
>= MAX_CONFIG_ROM_SIZE
)) {
594 /* Read header quadlet for the block to get the length. */
595 ret
= read_rom(device
, generation
, i
, &rom
[i
]);
596 if (ret
!= RCODE_COMPLETE
)
598 end
= i
+ (rom
[i
] >> 16) + 1;
599 if (end
> MAX_CONFIG_ROM_SIZE
) {
601 * This block extends outside the config ROM which is
602 * a firmware bug. Ignore this whole block, i.e.
603 * simply set a fake block length of 0.
605 fw_err(card
, "skipped invalid ROM block %x at %llx\n",
607 i
* 4 | CSR_REGISTER_BASE
| CSR_CONFIG_ROM
);
614 * Now read in the block. If this is a directory
615 * block, check the entries as we read them to see if
616 * it references another block, and push it in that case.
618 for (; i
< end
; i
++) {
619 ret
= read_rom(device
, generation
, i
, &rom
[i
]);
620 if (ret
!= RCODE_COMPLETE
)
623 if ((key
>> 30) != 3 || (rom
[i
] >> 30) < 2)
626 * Offset points outside the ROM. May be a firmware
627 * bug or an Extended ROM entry (IEEE 1212-2001 clause
628 * 7.7.18). Simply overwrite this pointer here by a
629 * fake immediate entry so that later iterators over
630 * the ROM don't have to check offsets all the time.
632 if (i
+ (rom
[i
] & 0xffffff) >= MAX_CONFIG_ROM_SIZE
) {
634 "skipped unsupported ROM entry %x at %llx\n",
636 i
* 4 | CSR_REGISTER_BASE
| CSR_CONFIG_ROM
);
640 stack
[sp
++] = i
+ rom
[i
];
646 old_rom
= device
->config_rom
;
647 new_rom
= kmemdup(rom
, length
* 4, GFP_KERNEL
);
648 if (new_rom
== NULL
) {
653 down_write(&fw_device_rwsem
);
654 device
->config_rom
= new_rom
;
655 device
->config_rom_length
= length
;
656 up_write(&fw_device_rwsem
);
659 ret
= RCODE_COMPLETE
;
660 device
->max_rec
= rom
[2] >> 12 & 0xf;
661 device
->cmc
= rom
[2] >> 30 & 1;
662 device
->irmc
= rom
[2] >> 31 & 1;
669 static void fw_unit_release(struct device
*dev
)
671 struct fw_unit
*unit
= fw_unit(dev
);
673 fw_device_put(fw_parent_device(unit
));
677 static struct device_type fw_unit_type
= {
678 .uevent
= fw_unit_uevent
,
679 .release
= fw_unit_release
,
682 static bool is_fw_unit(struct device
*dev
)
684 return dev
->type
== &fw_unit_type
;
687 static void create_units(struct fw_device
*device
)
689 struct fw_csr_iterator ci
;
690 struct fw_unit
*unit
;
694 fw_csr_iterator_init(&ci
, &device
->config_rom
[5]);
695 while (fw_csr_iterator_next(&ci
, &key
, &value
)) {
696 if (key
!= (CSR_UNIT
| CSR_DIRECTORY
))
700 * Get the address of the unit directory and try to
701 * match the drivers id_tables against it.
703 unit
= kzalloc(sizeof(*unit
), GFP_KERNEL
);
707 unit
->directory
= ci
.p
+ value
- 1;
708 unit
->device
.bus
= &fw_bus_type
;
709 unit
->device
.type
= &fw_unit_type
;
710 unit
->device
.parent
= &device
->device
;
711 dev_set_name(&unit
->device
, "%s.%d", dev_name(&device
->device
), i
++);
713 BUILD_BUG_ON(ARRAY_SIZE(unit
->attribute_group
.attrs
) <
714 ARRAY_SIZE(fw_unit_attributes
) +
715 ARRAY_SIZE(config_rom_attributes
));
716 init_fw_attribute_group(&unit
->device
,
718 &unit
->attribute_group
);
720 fw_device_get(device
);
721 if (device_register(&unit
->device
) < 0) {
722 put_device(&unit
->device
);
728 static int shutdown_unit(struct device
*device
, void *data
)
730 device_unregister(device
);
736 * fw_device_rwsem acts as dual purpose mutex:
737 * - serializes accesses to fw_device_idr,
738 * - serializes accesses to fw_device.config_rom/.config_rom_length and
739 * fw_unit.directory, unless those accesses happen at safe occasions
741 DECLARE_RWSEM(fw_device_rwsem
);
743 DEFINE_IDR(fw_device_idr
);
746 struct fw_device
*fw_device_get_by_devt(dev_t devt
)
748 struct fw_device
*device
;
750 down_read(&fw_device_rwsem
);
751 device
= idr_find(&fw_device_idr
, MINOR(devt
));
753 fw_device_get(device
);
754 up_read(&fw_device_rwsem
);
759 struct workqueue_struct
*fw_workqueue
;
760 EXPORT_SYMBOL(fw_workqueue
);
762 static void fw_schedule_device_work(struct fw_device
*device
,
765 queue_delayed_work(fw_workqueue
, &device
->work
, delay
);
769 * These defines control the retry behavior for reading the config
770 * rom. It shouldn't be necessary to tweak these; if the device
771 * doesn't respond to a config rom read within 10 seconds, it's not
772 * going to respond at all. As for the initial delay, a lot of
773 * devices will be able to respond within half a second after bus
774 * reset. On the other hand, it's not really worth being more
775 * aggressive than that, since it scales pretty well; if 10 devices
776 * are plugged in, they're all getting read within one second.
779 #define MAX_RETRIES 10
780 #define RETRY_DELAY (3 * HZ)
781 #define INITIAL_DELAY (HZ / 2)
782 #define SHUTDOWN_DELAY (2 * HZ)
784 static void fw_device_shutdown(struct work_struct
*work
)
786 struct fw_device
*device
=
787 container_of(work
, struct fw_device
, work
.work
);
788 int minor
= MINOR(device
->device
.devt
);
790 if (time_before64(get_jiffies_64(),
791 device
->card
->reset_jiffies
+ SHUTDOWN_DELAY
)
792 && !list_empty(&device
->card
->link
)) {
793 fw_schedule_device_work(device
, SHUTDOWN_DELAY
);
797 if (atomic_cmpxchg(&device
->state
,
799 FW_DEVICE_SHUTDOWN
) != FW_DEVICE_GONE
)
802 fw_device_cdev_remove(device
);
803 device_for_each_child(&device
->device
, NULL
, shutdown_unit
);
804 device_unregister(&device
->device
);
806 down_write(&fw_device_rwsem
);
807 idr_remove(&fw_device_idr
, minor
);
808 up_write(&fw_device_rwsem
);
810 fw_device_put(device
);
813 static void fw_device_release(struct device
*dev
)
815 struct fw_device
*device
= fw_device(dev
);
816 struct fw_card
*card
= device
->card
;
820 * Take the card lock so we don't set this to NULL while a
821 * FW_NODE_UPDATED callback is being handled or while the
822 * bus manager work looks at this node.
824 spin_lock_irqsave(&card
->lock
, flags
);
825 device
->node
->data
= NULL
;
826 spin_unlock_irqrestore(&card
->lock
, flags
);
828 fw_node_put(device
->node
);
829 kfree(device
->config_rom
);
834 static struct device_type fw_device_type
= {
835 .release
= fw_device_release
,
838 static bool is_fw_device(struct device
*dev
)
840 return dev
->type
== &fw_device_type
;
843 static int update_unit(struct device
*dev
, void *data
)
845 struct fw_unit
*unit
= fw_unit(dev
);
846 struct fw_driver
*driver
= (struct fw_driver
*)dev
->driver
;
848 if (is_fw_unit(dev
) && driver
!= NULL
&& driver
->update
!= NULL
) {
850 driver
->update(unit
);
857 static void fw_device_update(struct work_struct
*work
)
859 struct fw_device
*device
=
860 container_of(work
, struct fw_device
, work
.work
);
862 fw_device_cdev_update(device
);
863 device_for_each_child(&device
->device
, NULL
, update_unit
);
867 * If a device was pending for deletion because its node went away but its
868 * bus info block and root directory header matches that of a newly discovered
869 * device, revive the existing fw_device.
870 * The newly allocated fw_device becomes obsolete instead.
872 static int lookup_existing_device(struct device
*dev
, void *data
)
874 struct fw_device
*old
= fw_device(dev
);
875 struct fw_device
*new = data
;
876 struct fw_card
*card
= new->card
;
879 if (!is_fw_device(dev
))
882 down_read(&fw_device_rwsem
); /* serialize config_rom access */
883 spin_lock_irq(&card
->lock
); /* serialize node access */
885 if (memcmp(old
->config_rom
, new->config_rom
, 6 * 4) == 0 &&
886 atomic_cmpxchg(&old
->state
,
888 FW_DEVICE_RUNNING
) == FW_DEVICE_GONE
) {
889 struct fw_node
*current_node
= new->node
;
890 struct fw_node
*obsolete_node
= old
->node
;
892 new->node
= obsolete_node
;
893 new->node
->data
= new;
894 old
->node
= current_node
;
895 old
->node
->data
= old
;
897 old
->max_speed
= new->max_speed
;
898 old
->node_id
= current_node
->node_id
;
899 smp_wmb(); /* update node_id before generation */
900 old
->generation
= card
->generation
;
901 old
->config_rom_retries
= 0;
902 fw_notice(card
, "rediscovered device %s\n", dev_name(dev
));
904 old
->workfn
= fw_device_update
;
905 fw_schedule_device_work(old
, 0);
907 if (current_node
== card
->root_node
)
908 fw_schedule_bm_work(card
, 0);
913 spin_unlock_irq(&card
->lock
);
914 up_read(&fw_device_rwsem
);
919 enum { BC_UNKNOWN
= 0, BC_UNIMPLEMENTED
, BC_IMPLEMENTED
, };
921 static void set_broadcast_channel(struct fw_device
*device
, int generation
)
923 struct fw_card
*card
= device
->card
;
927 if (!card
->broadcast_channel_allocated
)
931 * The Broadcast_Channel Valid bit is required by nodes which want to
932 * transmit on this channel. Such transmissions are practically
933 * exclusive to IP over 1394 (RFC 2734). IP capable nodes are required
934 * to be IRM capable and have a max_rec of 8 or more. We use this fact
935 * to narrow down to which nodes we send Broadcast_Channel updates.
937 if (!device
->irmc
|| device
->max_rec
< 8)
941 * Some 1394-1995 nodes crash if this 1394a-2000 register is written.
942 * Perform a read test first.
944 if (device
->bc_implemented
== BC_UNKNOWN
) {
945 rcode
= fw_run_transaction(card
, TCODE_READ_QUADLET_REQUEST
,
946 device
->node_id
, generation
, device
->max_speed
,
947 CSR_REGISTER_BASE
+ CSR_BROADCAST_CHANNEL
,
951 if (data
& cpu_to_be32(1 << 31)) {
952 device
->bc_implemented
= BC_IMPLEMENTED
;
955 fallthrough
; /* to case address error */
956 case RCODE_ADDRESS_ERROR
:
957 device
->bc_implemented
= BC_UNIMPLEMENTED
;
961 if (device
->bc_implemented
== BC_IMPLEMENTED
) {
962 data
= cpu_to_be32(BROADCAST_CHANNEL_INITIAL
|
963 BROADCAST_CHANNEL_VALID
);
964 fw_run_transaction(card
, TCODE_WRITE_QUADLET_REQUEST
,
965 device
->node_id
, generation
, device
->max_speed
,
966 CSR_REGISTER_BASE
+ CSR_BROADCAST_CHANNEL
,
971 int fw_device_set_broadcast_channel(struct device
*dev
, void *gen
)
973 if (is_fw_device(dev
))
974 set_broadcast_channel(fw_device(dev
), (long)gen
);
979 static void fw_device_init(struct work_struct
*work
)
981 struct fw_device
*device
=
982 container_of(work
, struct fw_device
, work
.work
);
983 struct fw_card
*card
= device
->card
;
984 struct device
*revived_dev
;
988 * All failure paths here set node->data to NULL, so that we
989 * don't try to do device_for_each_child() on a kfree()'d
993 ret
= read_config_rom(device
, device
->generation
);
994 if (ret
!= RCODE_COMPLETE
) {
995 if (device
->config_rom_retries
< MAX_RETRIES
&&
996 atomic_read(&device
->state
) == FW_DEVICE_INITIALIZING
) {
997 device
->config_rom_retries
++;
998 fw_schedule_device_work(device
, RETRY_DELAY
);
1000 if (device
->node
->link_on
)
1001 fw_notice(card
, "giving up on node %x: reading config rom failed: %s\n",
1003 fw_rcode_string(ret
));
1004 if (device
->node
== card
->root_node
)
1005 fw_schedule_bm_work(card
, 0);
1006 fw_device_release(&device
->device
);
1011 revived_dev
= device_find_child(card
->device
,
1012 device
, lookup_existing_device
);
1014 put_device(revived_dev
);
1015 fw_device_release(&device
->device
);
1020 device_initialize(&device
->device
);
1022 fw_device_get(device
);
1023 down_write(&fw_device_rwsem
);
1024 minor
= idr_alloc(&fw_device_idr
, device
, 0, 1 << MINORBITS
,
1026 up_write(&fw_device_rwsem
);
1031 device
->device
.bus
= &fw_bus_type
;
1032 device
->device
.type
= &fw_device_type
;
1033 device
->device
.parent
= card
->device
;
1034 device
->device
.devt
= MKDEV(fw_cdev_major
, minor
);
1035 dev_set_name(&device
->device
, "fw%d", minor
);
1037 BUILD_BUG_ON(ARRAY_SIZE(device
->attribute_group
.attrs
) <
1038 ARRAY_SIZE(fw_device_attributes
) +
1039 ARRAY_SIZE(config_rom_attributes
));
1040 init_fw_attribute_group(&device
->device
,
1041 fw_device_attributes
,
1042 &device
->attribute_group
);
1044 if (device_add(&device
->device
)) {
1045 fw_err(card
, "failed to add device\n");
1046 goto error_with_cdev
;
1049 create_units(device
);
1052 * Transition the device to running state. If it got pulled
1053 * out from under us while we did the initialization work, we
1054 * have to shut down the device again here. Normally, though,
1055 * fw_node_event will be responsible for shutting it down when
1056 * necessary. We have to use the atomic cmpxchg here to avoid
1057 * racing with the FW_NODE_DESTROYED case in
1060 if (atomic_cmpxchg(&device
->state
,
1061 FW_DEVICE_INITIALIZING
,
1062 FW_DEVICE_RUNNING
) == FW_DEVICE_GONE
) {
1063 device
->workfn
= fw_device_shutdown
;
1064 fw_schedule_device_work(device
, SHUTDOWN_DELAY
);
1066 fw_notice(card
, "created device %s: GUID %08x%08x, S%d00\n",
1067 dev_name(&device
->device
),
1068 device
->config_rom
[3], device
->config_rom
[4],
1069 1 << device
->max_speed
);
1070 device
->config_rom_retries
= 0;
1072 set_broadcast_channel(device
, device
->generation
);
1074 add_device_randomness(&device
->config_rom
[3], 8);
1078 * Reschedule the IRM work if we just finished reading the
1079 * root node config rom. If this races with a bus reset we
1080 * just end up running the IRM work a couple of extra times -
1083 if (device
->node
== card
->root_node
)
1084 fw_schedule_bm_work(card
, 0);
1089 down_write(&fw_device_rwsem
);
1090 idr_remove(&fw_device_idr
, minor
);
1091 up_write(&fw_device_rwsem
);
1093 fw_device_put(device
); /* fw_device_idr's reference */
1095 put_device(&device
->device
); /* our reference */
1098 /* Reread and compare bus info block and header of root directory */
1099 static int reread_config_rom(struct fw_device
*device
, int generation
,
1105 for (i
= 0; i
< 6; i
++) {
1106 rcode
= read_rom(device
, generation
, i
, &q
);
1107 if (rcode
!= RCODE_COMPLETE
)
1110 if (i
== 0 && q
== 0)
1111 /* inaccessible (see read_config_rom); retry later */
1114 if (q
!= device
->config_rom
[i
]) {
1116 return RCODE_COMPLETE
;
1121 return RCODE_COMPLETE
;
1124 static void fw_device_refresh(struct work_struct
*work
)
1126 struct fw_device
*device
=
1127 container_of(work
, struct fw_device
, work
.work
);
1128 struct fw_card
*card
= device
->card
;
1129 int ret
, node_id
= device
->node_id
;
1132 ret
= reread_config_rom(device
, device
->generation
, &changed
);
1133 if (ret
!= RCODE_COMPLETE
)
1134 goto failed_config_rom
;
1137 if (atomic_cmpxchg(&device
->state
,
1138 FW_DEVICE_INITIALIZING
,
1139 FW_DEVICE_RUNNING
) == FW_DEVICE_GONE
)
1142 fw_device_update(work
);
1143 device
->config_rom_retries
= 0;
1148 * Something changed. We keep things simple and don't investigate
1149 * further. We just destroy all previous units and create new ones.
1151 device_for_each_child(&device
->device
, NULL
, shutdown_unit
);
1153 ret
= read_config_rom(device
, device
->generation
);
1154 if (ret
!= RCODE_COMPLETE
)
1155 goto failed_config_rom
;
1157 fw_device_cdev_update(device
);
1158 create_units(device
);
1160 /* Userspace may want to re-read attributes. */
1161 kobject_uevent(&device
->device
.kobj
, KOBJ_CHANGE
);
1163 if (atomic_cmpxchg(&device
->state
,
1164 FW_DEVICE_INITIALIZING
,
1165 FW_DEVICE_RUNNING
) == FW_DEVICE_GONE
)
1168 fw_notice(card
, "refreshed device %s\n", dev_name(&device
->device
));
1169 device
->config_rom_retries
= 0;
1173 if (device
->config_rom_retries
< MAX_RETRIES
&&
1174 atomic_read(&device
->state
) == FW_DEVICE_INITIALIZING
) {
1175 device
->config_rom_retries
++;
1176 fw_schedule_device_work(device
, RETRY_DELAY
);
1180 fw_notice(card
, "giving up on refresh of device %s: %s\n",
1181 dev_name(&device
->device
), fw_rcode_string(ret
));
1183 atomic_set(&device
->state
, FW_DEVICE_GONE
);
1184 device
->workfn
= fw_device_shutdown
;
1185 fw_schedule_device_work(device
, SHUTDOWN_DELAY
);
1187 if (node_id
== card
->root_node
->node_id
)
1188 fw_schedule_bm_work(card
, 0);
1191 static void fw_device_workfn(struct work_struct
*work
)
1193 struct fw_device
*device
= container_of(to_delayed_work(work
),
1194 struct fw_device
, work
);
1195 device
->workfn(work
);
1198 void fw_node_event(struct fw_card
*card
, struct fw_node
*node
, int event
)
1200 struct fw_device
*device
;
1203 case FW_NODE_CREATED
:
1205 * Attempt to scan the node, regardless whether its self ID has
1206 * the L (link active) flag set or not. Some broken devices
1207 * send L=0 but have an up-and-running link; others send L=1
1208 * without actually having a link.
1211 device
= kzalloc(sizeof(*device
), GFP_ATOMIC
);
1216 * Do minimal initialization of the device here, the
1217 * rest will happen in fw_device_init().
1219 * Attention: A lot of things, even fw_device_get(),
1220 * cannot be done before fw_device_init() finished!
1221 * You can basically just check device->state and
1222 * schedule work until then, but only while holding
1225 atomic_set(&device
->state
, FW_DEVICE_INITIALIZING
);
1226 device
->card
= fw_card_get(card
);
1227 device
->node
= fw_node_get(node
);
1228 device
->node_id
= node
->node_id
;
1229 device
->generation
= card
->generation
;
1230 device
->is_local
= node
== card
->local_node
;
1231 mutex_init(&device
->client_list_mutex
);
1232 INIT_LIST_HEAD(&device
->client_list
);
1235 * Set the node data to point back to this device so
1236 * FW_NODE_UPDATED callbacks can update the node_id
1237 * and generation for the device.
1239 node
->data
= device
;
1242 * Many devices are slow to respond after bus resets,
1243 * especially if they are bus powered and go through
1244 * power-up after getting plugged in. We schedule the
1245 * first config rom scan half a second after bus reset.
1247 device
->workfn
= fw_device_init
;
1248 INIT_DELAYED_WORK(&device
->work
, fw_device_workfn
);
1249 fw_schedule_device_work(device
, INITIAL_DELAY
);
1252 case FW_NODE_INITIATED_RESET
:
1253 case FW_NODE_LINK_ON
:
1254 device
= node
->data
;
1258 device
->node_id
= node
->node_id
;
1259 smp_wmb(); /* update node_id before generation */
1260 device
->generation
= card
->generation
;
1261 if (atomic_cmpxchg(&device
->state
,
1263 FW_DEVICE_INITIALIZING
) == FW_DEVICE_RUNNING
) {
1264 device
->workfn
= fw_device_refresh
;
1265 fw_schedule_device_work(device
,
1266 device
->is_local
? 0 : INITIAL_DELAY
);
1270 case FW_NODE_UPDATED
:
1271 device
= node
->data
;
1275 device
->node_id
= node
->node_id
;
1276 smp_wmb(); /* update node_id before generation */
1277 device
->generation
= card
->generation
;
1278 if (atomic_read(&device
->state
) == FW_DEVICE_RUNNING
) {
1279 device
->workfn
= fw_device_update
;
1280 fw_schedule_device_work(device
, 0);
1284 case FW_NODE_DESTROYED
:
1285 case FW_NODE_LINK_OFF
:
1290 * Destroy the device associated with the node. There
1291 * are two cases here: either the device is fully
1292 * initialized (FW_DEVICE_RUNNING) or we're in the
1293 * process of reading its config rom
1294 * (FW_DEVICE_INITIALIZING). If it is fully
1295 * initialized we can reuse device->work to schedule a
1296 * full fw_device_shutdown(). If not, there's work
1297 * scheduled to read it's config rom, and we just put
1298 * the device in shutdown state to have that code fail
1299 * to create the device.
1301 device
= node
->data
;
1302 if (atomic_xchg(&device
->state
,
1303 FW_DEVICE_GONE
) == FW_DEVICE_RUNNING
) {
1304 device
->workfn
= fw_device_shutdown
;
1305 fw_schedule_device_work(device
,
1306 list_empty(&card
->link
) ? 0 : SHUTDOWN_DELAY
);