1 // SPDX-License-Identifier: GPL-2.0-only
5 * Copyright (C) 2008 James Bottomley <James.Bottomley@HansenPartnership.com>
7 **-----------------------------------------------------------------------------
10 **-----------------------------------------------------------------------------
12 #include <linux/device.h>
13 #include <linux/enclosure.h>
14 #include <linux/err.h>
15 #include <linux/list.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/mutex.h>
19 #include <linux/slab.h>
21 static LIST_HEAD(container_list);
22 static DEFINE_MUTEX(container_list_lock);
23 static struct class enclosure_class;
26 * enclosure_find - find an enclosure given a parent device
27 * @dev: the parent to match against
28 * @start: Optional enclosure device to start from (NULL if none)
30 * Looks through the list of registered enclosures to find all those
31 * with @dev as a parent. Returns NULL if no enclosure is
32 * found. @start can be used as a starting point to obtain multiple
33 * enclosures per parent (should begin with NULL and then be set to
34 * each returned enclosure device). Obtains a reference to the
35 * enclosure class device which must be released with device_put().
36 * If @start is not NULL, a reference must be taken on it which is
37 * released before returning (this allows a loop through all
38 * enclosures to exit with only the reference on the enclosure of
39 * interest held). Note that the @dev may correspond to the actual
40 * device housing the enclosure, in which case no iteration via @start
43 struct enclosure_device *enclosure_find(struct device *dev,
44 struct enclosure_device *start)
46 struct enclosure_device *edev;
48 mutex_lock(&container_list_lock);
49 edev = list_prepare_entry(start, &container_list, node);
51 put_device(&start->edev);
53 list_for_each_entry_continue(edev, &container_list, node) {
54 struct device *parent = edev->edev.parent;
55 /* parent might not be immediate, so iterate up to
56 * the root of the tree if necessary */
59 get_device(&edev->edev);
60 mutex_unlock(&container_list_lock);
63 parent = parent->parent;
66 mutex_unlock(&container_list_lock);
70 EXPORT_SYMBOL_GPL(enclosure_find);
73 * enclosure_for_each_device - calls a function for each enclosure
74 * @fn: the function to call
75 * @data: the data to pass to each call
77 * Loops over all the enclosures calling the function.
79 * Note, this function uses a mutex which will be held across calls to
80 * @fn, so it must have non atomic context, and @fn may (although it
81 * should not) sleep or otherwise cause the mutex to be held for
84 int enclosure_for_each_device(int (*fn)(struct enclosure_device *, void *),
88 struct enclosure_device *edev;
90 mutex_lock(&container_list_lock);
91 list_for_each_entry(edev, &container_list, node) {
92 error = fn(edev, data);
96 mutex_unlock(&container_list_lock);
100 EXPORT_SYMBOL_GPL(enclosure_for_each_device);
103 * enclosure_register - register device as an enclosure
105 * @dev: device containing the enclosure
106 * @name: chosen device name
107 * @components: number of components in the enclosure
108 * @cb: platform call-backs
110 * This sets up the device for being an enclosure. Note that @dev does
111 * not have to be a dedicated enclosure device. It may be some other type
112 * of device that additionally responds to enclosure services
114 struct enclosure_device *
115 enclosure_register(struct device *dev, const char *name, int components,
116 struct enclosure_component_callbacks *cb)
118 struct enclosure_device *edev =
119 kzalloc(struct_size(edev, component, components), GFP_KERNEL);
125 return ERR_PTR(-ENOMEM);
127 edev->components = components;
129 edev->edev.class = &enclosure_class;
130 edev->edev.parent = get_device(dev);
132 dev_set_name(&edev->edev, "%s", name);
133 err = device_register(&edev->edev);
137 for (i = 0; i < components; i++) {
138 edev->component[i].number = -1;
139 edev->component[i].slot = -1;
140 edev->component[i].power_status = -1;
143 mutex_lock(&container_list_lock);
144 list_add_tail(&edev->node, &container_list);
145 mutex_unlock(&container_list_lock);
150 put_device(edev->edev.parent);
154 EXPORT_SYMBOL_GPL(enclosure_register);
156 static struct enclosure_component_callbacks enclosure_null_callbacks;
159 * enclosure_unregister - remove an enclosure
161 * @edev: the registered enclosure to remove;
163 void enclosure_unregister(struct enclosure_device *edev)
167 mutex_lock(&container_list_lock);
168 list_del(&edev->node);
169 mutex_unlock(&container_list_lock);
171 for (i = 0; i < edev->components; i++)
172 if (edev->component[i].number != -1)
173 device_unregister(&edev->component[i].cdev);
175 /* prevent any callbacks into service user */
176 edev->cb = &enclosure_null_callbacks;
177 device_unregister(&edev->edev);
179 EXPORT_SYMBOL_GPL(enclosure_unregister);
181 #define ENCLOSURE_NAME_SIZE 64
182 #define COMPONENT_NAME_SIZE 64
184 static void enclosure_link_name(struct enclosure_component *cdev, char *name)
186 strcpy(name, "enclosure_device:");
187 strcat(name, dev_name(&cdev->cdev));
190 static void enclosure_remove_links(struct enclosure_component *cdev)
192 char name[ENCLOSURE_NAME_SIZE];
194 enclosure_link_name(cdev, name);
197 * In odd circumstances, like multipath devices, something else may
198 * already have removed the links, so check for this condition first.
200 if (cdev->dev->kobj.sd)
201 sysfs_remove_link(&cdev->dev->kobj, name);
203 if (cdev->cdev.kobj.sd)
204 sysfs_remove_link(&cdev->cdev.kobj, "device");
207 static int enclosure_add_links(struct enclosure_component *cdev)
210 char name[ENCLOSURE_NAME_SIZE];
212 error = sysfs_create_link(&cdev->cdev.kobj, &cdev->dev->kobj, "device");
216 enclosure_link_name(cdev, name);
217 error = sysfs_create_link(&cdev->dev->kobj, &cdev->cdev.kobj, name);
219 sysfs_remove_link(&cdev->cdev.kobj, "device");
224 static void enclosure_release(struct device *cdev)
226 struct enclosure_device *edev = to_enclosure_device(cdev);
228 put_device(cdev->parent);
232 static void enclosure_component_release(struct device *dev)
234 struct enclosure_component *cdev = to_enclosure_component(dev);
237 enclosure_remove_links(cdev);
238 put_device(cdev->dev);
240 put_device(dev->parent);
243 static struct enclosure_component *
244 enclosure_component_find_by_name(struct enclosure_device *edev,
249 struct enclosure_component *ecomp;
251 if (!edev || !name || !name[0])
254 for (i = 0; i < edev->components; i++) {
255 ecomp = &edev->component[i];
256 cname = dev_name(&ecomp->cdev);
257 if (ecomp->number != -1 &&
259 !strcmp(cname, name))
266 static const struct attribute_group *enclosure_component_groups[];
269 * enclosure_component_alloc - prepare a new enclosure component
270 * @edev: the enclosure to add the component
271 * @number: the device number
272 * @type: the type of component being added
273 * @name: an optional name to appear in sysfs (leave NULL if none)
275 * The name is optional for enclosures that give their components a unique
276 * name. If not, leave the field NULL and a name will be assigned.
278 * Returns a pointer to the enclosure component or an error.
280 struct enclosure_component *
281 enclosure_component_alloc(struct enclosure_device *edev,
283 enum enclosure_component_type type,
286 struct enclosure_component *ecomp;
289 char newname[COMPONENT_NAME_SIZE];
291 if (number >= edev->components)
292 return ERR_PTR(-EINVAL);
294 ecomp = &edev->component[number];
296 if (ecomp->number != -1)
297 return ERR_PTR(-EINVAL);
300 ecomp->number = number;
302 cdev->parent = get_device(&edev->edev);
304 if (name && name[0]) {
305 /* Some hardware (e.g. enclosure in RX300 S6) has components
306 * with non unique names. Registering duplicates in sysfs
307 * will lead to warnings during bootup. So make the names
308 * unique by appending consecutive numbers -1, -2, ... */
310 snprintf(newname, COMPONENT_NAME_SIZE,
312 while (enclosure_component_find_by_name(edev, newname))
313 snprintf(newname, COMPONENT_NAME_SIZE,
315 dev_set_name(cdev, "%s", newname);
317 dev_set_name(cdev, "%u", number);
319 cdev->release = enclosure_component_release;
320 cdev->groups = enclosure_component_groups;
324 EXPORT_SYMBOL_GPL(enclosure_component_alloc);
327 * enclosure_component_register - publishes an initialized enclosure component
328 * @ecomp: component to add
330 * Returns 0 on successful registration, releases the component otherwise
332 int enclosure_component_register(struct enclosure_component *ecomp)
338 err = device_register(cdev);
347 EXPORT_SYMBOL_GPL(enclosure_component_register);
350 * enclosure_add_device - add a device as being part of an enclosure
351 * @edev: the enclosure device being added to.
352 * @component: the number of the component
353 * @dev: the device being added
355 * Declares a real device to reside in slot (or identifier) @num of an
356 * enclosure. This will cause the relevant sysfs links to appear.
357 * This function may also be used to change a device associated with
358 * an enclosure without having to call enclosure_remove_device() in
361 * Returns zero on success or an error.
363 int enclosure_add_device(struct enclosure_device *edev, int component,
366 struct enclosure_component *cdev;
369 if (!edev || component >= edev->components)
372 cdev = &edev->component[component];
374 if (cdev->dev == dev)
378 enclosure_remove_links(cdev);
379 put_device(cdev->dev);
381 cdev->dev = get_device(dev);
382 err = enclosure_add_links(cdev);
384 put_device(cdev->dev);
389 EXPORT_SYMBOL_GPL(enclosure_add_device);
392 * enclosure_remove_device - remove a device from an enclosure
393 * @edev: the enclosure device
394 * @dev: device to remove/put
396 * Returns zero on success or an error.
399 int enclosure_remove_device(struct enclosure_device *edev, struct device *dev)
401 struct enclosure_component *cdev;
407 for (i = 0; i < edev->components; i++) {
408 cdev = &edev->component[i];
409 if (cdev->dev == dev) {
410 enclosure_remove_links(cdev);
418 EXPORT_SYMBOL_GPL(enclosure_remove_device);
424 static ssize_t components_show(struct device *cdev,
425 struct device_attribute *attr, char *buf)
427 struct enclosure_device *edev = to_enclosure_device(cdev);
429 return snprintf(buf, 40, "%d\n", edev->components);
431 static DEVICE_ATTR_RO(components);
433 static ssize_t id_show(struct device *cdev,
434 struct device_attribute *attr,
437 struct enclosure_device *edev = to_enclosure_device(cdev);
439 if (edev->cb->show_id)
440 return edev->cb->show_id(edev, buf);
443 static DEVICE_ATTR_RO(id);
445 static struct attribute *enclosure_class_attrs[] = {
446 &dev_attr_components.attr,
450 ATTRIBUTE_GROUPS(enclosure_class);
452 static struct class enclosure_class = {
454 .owner = THIS_MODULE,
455 .dev_release = enclosure_release,
456 .dev_groups = enclosure_class_groups,
459 static const char *const enclosure_status[] = {
460 [ENCLOSURE_STATUS_UNSUPPORTED] = "unsupported",
461 [ENCLOSURE_STATUS_OK] = "OK",
462 [ENCLOSURE_STATUS_CRITICAL] = "critical",
463 [ENCLOSURE_STATUS_NON_CRITICAL] = "non-critical",
464 [ENCLOSURE_STATUS_UNRECOVERABLE] = "unrecoverable",
465 [ENCLOSURE_STATUS_NOT_INSTALLED] = "not installed",
466 [ENCLOSURE_STATUS_UNKNOWN] = "unknown",
467 [ENCLOSURE_STATUS_UNAVAILABLE] = "unavailable",
468 [ENCLOSURE_STATUS_MAX] = NULL,
471 static const char *const enclosure_type[] = {
472 [ENCLOSURE_COMPONENT_DEVICE] = "device",
473 [ENCLOSURE_COMPONENT_ARRAY_DEVICE] = "array device",
476 static ssize_t get_component_fault(struct device *cdev,
477 struct device_attribute *attr, char *buf)
479 struct enclosure_device *edev = to_enclosure_device(cdev->parent);
480 struct enclosure_component *ecomp = to_enclosure_component(cdev);
482 if (edev->cb->get_fault)
483 edev->cb->get_fault(edev, ecomp);
484 return snprintf(buf, 40, "%d\n", ecomp->fault);
487 static ssize_t set_component_fault(struct device *cdev,
488 struct device_attribute *attr,
489 const char *buf, size_t count)
491 struct enclosure_device *edev = to_enclosure_device(cdev->parent);
492 struct enclosure_component *ecomp = to_enclosure_component(cdev);
493 int val = simple_strtoul(buf, NULL, 0);
495 if (edev->cb->set_fault)
496 edev->cb->set_fault(edev, ecomp, val);
500 static ssize_t get_component_status(struct device *cdev,
501 struct device_attribute *attr,char *buf)
503 struct enclosure_device *edev = to_enclosure_device(cdev->parent);
504 struct enclosure_component *ecomp = to_enclosure_component(cdev);
506 if (edev->cb->get_status)
507 edev->cb->get_status(edev, ecomp);
508 return snprintf(buf, 40, "%s\n", enclosure_status[ecomp->status]);
511 static ssize_t set_component_status(struct device *cdev,
512 struct device_attribute *attr,
513 const char *buf, size_t count)
515 struct enclosure_device *edev = to_enclosure_device(cdev->parent);
516 struct enclosure_component *ecomp = to_enclosure_component(cdev);
519 for (i = 0; enclosure_status[i]; i++) {
520 if (strncmp(buf, enclosure_status[i],
521 strlen(enclosure_status[i])) == 0 &&
522 (buf[strlen(enclosure_status[i])] == '\n' ||
523 buf[strlen(enclosure_status[i])] == '\0'))
527 if (enclosure_status[i] && edev->cb->set_status) {
528 edev->cb->set_status(edev, ecomp, i);
534 static ssize_t get_component_active(struct device *cdev,
535 struct device_attribute *attr, char *buf)
537 struct enclosure_device *edev = to_enclosure_device(cdev->parent);
538 struct enclosure_component *ecomp = to_enclosure_component(cdev);
540 if (edev->cb->get_active)
541 edev->cb->get_active(edev, ecomp);
542 return snprintf(buf, 40, "%d\n", ecomp->active);
545 static ssize_t set_component_active(struct device *cdev,
546 struct device_attribute *attr,
547 const char *buf, size_t count)
549 struct enclosure_device *edev = to_enclosure_device(cdev->parent);
550 struct enclosure_component *ecomp = to_enclosure_component(cdev);
551 int val = simple_strtoul(buf, NULL, 0);
553 if (edev->cb->set_active)
554 edev->cb->set_active(edev, ecomp, val);
558 static ssize_t get_component_locate(struct device *cdev,
559 struct device_attribute *attr, char *buf)
561 struct enclosure_device *edev = to_enclosure_device(cdev->parent);
562 struct enclosure_component *ecomp = to_enclosure_component(cdev);
564 if (edev->cb->get_locate)
565 edev->cb->get_locate(edev, ecomp);
566 return snprintf(buf, 40, "%d\n", ecomp->locate);
569 static ssize_t set_component_locate(struct device *cdev,
570 struct device_attribute *attr,
571 const char *buf, size_t count)
573 struct enclosure_device *edev = to_enclosure_device(cdev->parent);
574 struct enclosure_component *ecomp = to_enclosure_component(cdev);
575 int val = simple_strtoul(buf, NULL, 0);
577 if (edev->cb->set_locate)
578 edev->cb->set_locate(edev, ecomp, val);
582 static ssize_t get_component_power_status(struct device *cdev,
583 struct device_attribute *attr,
586 struct enclosure_device *edev = to_enclosure_device(cdev->parent);
587 struct enclosure_component *ecomp = to_enclosure_component(cdev);
589 if (edev->cb->get_power_status)
590 edev->cb->get_power_status(edev, ecomp);
592 /* If still uninitialized, the callback failed or does not exist. */
593 if (ecomp->power_status == -1)
594 return (edev->cb->get_power_status) ? -EIO : -ENOTTY;
596 return snprintf(buf, 40, "%s\n", ecomp->power_status ? "on" : "off");
599 static ssize_t set_component_power_status(struct device *cdev,
600 struct device_attribute *attr,
601 const char *buf, size_t count)
603 struct enclosure_device *edev = to_enclosure_device(cdev->parent);
604 struct enclosure_component *ecomp = to_enclosure_component(cdev);
607 if (strncmp(buf, "on", 2) == 0 &&
608 (buf[2] == '\n' || buf[2] == '\0'))
610 else if (strncmp(buf, "off", 3) == 0 &&
611 (buf[3] == '\n' || buf[3] == '\0'))
616 if (edev->cb->set_power_status)
617 edev->cb->set_power_status(edev, ecomp, val);
621 static ssize_t get_component_type(struct device *cdev,
622 struct device_attribute *attr, char *buf)
624 struct enclosure_component *ecomp = to_enclosure_component(cdev);
626 return snprintf(buf, 40, "%s\n", enclosure_type[ecomp->type]);
629 static ssize_t get_component_slot(struct device *cdev,
630 struct device_attribute *attr, char *buf)
632 struct enclosure_component *ecomp = to_enclosure_component(cdev);
635 /* if the enclosure does not override then use 'number' as a stand-in */
636 if (ecomp->slot >= 0)
639 slot = ecomp->number;
641 return snprintf(buf, 40, "%d\n", slot);
644 static DEVICE_ATTR(fault, S_IRUGO | S_IWUSR, get_component_fault,
645 set_component_fault);
646 static DEVICE_ATTR(status, S_IRUGO | S_IWUSR, get_component_status,
647 set_component_status);
648 static DEVICE_ATTR(active, S_IRUGO | S_IWUSR, get_component_active,
649 set_component_active);
650 static DEVICE_ATTR(locate, S_IRUGO | S_IWUSR, get_component_locate,
651 set_component_locate);
652 static DEVICE_ATTR(power_status, S_IRUGO | S_IWUSR, get_component_power_status,
653 set_component_power_status);
654 static DEVICE_ATTR(type, S_IRUGO, get_component_type, NULL);
655 static DEVICE_ATTR(slot, S_IRUGO, get_component_slot, NULL);
657 static struct attribute *enclosure_component_attrs[] = {
658 &dev_attr_fault.attr,
659 &dev_attr_status.attr,
660 &dev_attr_active.attr,
661 &dev_attr_locate.attr,
662 &dev_attr_power_status.attr,
667 ATTRIBUTE_GROUPS(enclosure_component);
669 static int __init enclosure_init(void)
671 return class_register(&enclosure_class);
674 static void __exit enclosure_exit(void)
676 class_unregister(&enclosure_class);
679 module_init(enclosure_init);
680 module_exit(enclosure_exit);
682 MODULE_AUTHOR("James Bottomley");
683 MODULE_DESCRIPTION("Enclosure Services");
684 MODULE_LICENSE("GPL v2");