diff options
Diffstat (limited to 'drivers/misc/enclosure.c')
| -rw-r--r-- | drivers/misc/enclosure.c | 684 |
1 files changed, 684 insertions, 0 deletions
diff --git a/drivers/misc/enclosure.c b/drivers/misc/enclosure.c new file mode 100644 index 000000000..1b010d926 --- /dev/null +++ b/drivers/misc/enclosure.c @@ -0,0 +1,684 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Enclosure Services + * + * Copyright (C) 2008 James Bottomley <James.Bottomley@HansenPartnership.com> + * +**----------------------------------------------------------------------------- +** +** +**----------------------------------------------------------------------------- +*/ +#include <linux/device.h> +#include <linux/enclosure.h> +#include <linux/err.h> +#include <linux/list.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/slab.h> + +static LIST_HEAD(container_list); +static DEFINE_MUTEX(container_list_lock); +static struct class enclosure_class; + +/** + * enclosure_find - find an enclosure given a parent device + * @dev: the parent to match against + * @start: Optional enclosure device to start from (NULL if none) + * + * Looks through the list of registered enclosures to find all those + * with @dev as a parent. Returns NULL if no enclosure is + * found. @start can be used as a starting point to obtain multiple + * enclosures per parent (should begin with NULL and then be set to + * each returned enclosure device). Obtains a reference to the + * enclosure class device which must be released with device_put(). + * If @start is not NULL, a reference must be taken on it which is + * released before returning (this allows a loop through all + * enclosures to exit with only the reference on the enclosure of + * interest held). Note that the @dev may correspond to the actual + * device housing the enclosure, in which case no iteration via @start + * is required. + */ +struct enclosure_device *enclosure_find(struct device *dev, + struct enclosure_device *start) +{ + struct enclosure_device *edev; + + mutex_lock(&container_list_lock); + edev = list_prepare_entry(start, &container_list, node); + if (start) + put_device(&start->edev); + + list_for_each_entry_continue(edev, &container_list, node) { + struct device *parent = edev->edev.parent; + /* parent might not be immediate, so iterate up to + * the root of the tree if necessary */ + while (parent) { + if (parent == dev) { + get_device(&edev->edev); + mutex_unlock(&container_list_lock); + return edev; + } + parent = parent->parent; + } + } + mutex_unlock(&container_list_lock); + + return NULL; +} +EXPORT_SYMBOL_GPL(enclosure_find); + +/** + * enclosure_for_each_device - calls a function for each enclosure + * @fn: the function to call + * @data: the data to pass to each call + * + * Loops over all the enclosures calling the function. + * + * Note, this function uses a mutex which will be held across calls to + * @fn, so it must have non atomic context, and @fn may (although it + * should not) sleep or otherwise cause the mutex to be held for + * indefinite periods + */ +int enclosure_for_each_device(int (*fn)(struct enclosure_device *, void *), + void *data) +{ + int error = 0; + struct enclosure_device *edev; + + mutex_lock(&container_list_lock); + list_for_each_entry(edev, &container_list, node) { + error = fn(edev, data); + if (error) + break; + } + mutex_unlock(&container_list_lock); + + return error; +} +EXPORT_SYMBOL_GPL(enclosure_for_each_device); + +/** + * enclosure_register - register device as an enclosure + * + * @dev: device containing the enclosure + * @name: chosen device name + * @components: number of components in the enclosure + * @cb: platform call-backs + * + * This sets up the device for being an enclosure. Note that @dev does + * not have to be a dedicated enclosure device. It may be some other type + * of device that additionally responds to enclosure services + */ +struct enclosure_device * +enclosure_register(struct device *dev, const char *name, int components, + struct enclosure_component_callbacks *cb) +{ + struct enclosure_device *edev = + kzalloc(struct_size(edev, component, components), GFP_KERNEL); + int err, i; + + BUG_ON(!cb); + + if (!edev) + return ERR_PTR(-ENOMEM); + + edev->components = components; + + edev->edev.class = &enclosure_class; + edev->edev.parent = get_device(dev); + edev->cb = cb; + dev_set_name(&edev->edev, "%s", name); + err = device_register(&edev->edev); + if (err) + goto err; + + for (i = 0; i < components; i++) { + edev->component[i].number = -1; + edev->component[i].slot = -1; + edev->component[i].power_status = -1; + } + + mutex_lock(&container_list_lock); + list_add_tail(&edev->node, &container_list); + mutex_unlock(&container_list_lock); + + return edev; + + err: + put_device(edev->edev.parent); + kfree(edev); + return ERR_PTR(err); +} +EXPORT_SYMBOL_GPL(enclosure_register); + +static struct enclosure_component_callbacks enclosure_null_callbacks; + +/** + * enclosure_unregister - remove an enclosure + * + * @edev: the registered enclosure to remove; + */ +void enclosure_unregister(struct enclosure_device *edev) +{ + int i; + + mutex_lock(&container_list_lock); + list_del(&edev->node); + mutex_unlock(&container_list_lock); + + for (i = 0; i < edev->components; i++) + if (edev->component[i].number != -1) + device_unregister(&edev->component[i].cdev); + + /* prevent any callbacks into service user */ + edev->cb = &enclosure_null_callbacks; + device_unregister(&edev->edev); +} +EXPORT_SYMBOL_GPL(enclosure_unregister); + +#define ENCLOSURE_NAME_SIZE 64 +#define COMPONENT_NAME_SIZE 64 + +static void enclosure_link_name(struct enclosure_component *cdev, char *name) +{ + strcpy(name, "enclosure_device:"); + strcat(name, dev_name(&cdev->cdev)); +} + +static void enclosure_remove_links(struct enclosure_component *cdev) +{ + char name[ENCLOSURE_NAME_SIZE]; + + enclosure_link_name(cdev, name); + + /* + * In odd circumstances, like multipath devices, something else may + * already have removed the links, so check for this condition first. + */ + if (cdev->dev->kobj.sd) + sysfs_remove_link(&cdev->dev->kobj, name); + + if (cdev->cdev.kobj.sd) + sysfs_remove_link(&cdev->cdev.kobj, "device"); +} + +static int enclosure_add_links(struct enclosure_component *cdev) +{ + int error; + char name[ENCLOSURE_NAME_SIZE]; + + error = sysfs_create_link(&cdev->cdev.kobj, &cdev->dev->kobj, "device"); + if (error) + return error; + + enclosure_link_name(cdev, name); + error = sysfs_create_link(&cdev->dev->kobj, &cdev->cdev.kobj, name); + if (error) + sysfs_remove_link(&cdev->cdev.kobj, "device"); + + return error; +} + +static void enclosure_release(struct device *cdev) +{ + struct enclosure_device *edev = to_enclosure_device(cdev); + + put_device(cdev->parent); + kfree(edev); +} + +static void enclosure_component_release(struct device *dev) +{ + struct enclosure_component *cdev = to_enclosure_component(dev); + + if (cdev->dev) { + enclosure_remove_links(cdev); + put_device(cdev->dev); + } + put_device(dev->parent); +} + +static struct enclosure_component * +enclosure_component_find_by_name(struct enclosure_device *edev, + const char *name) +{ + int i; + const char *cname; + struct enclosure_component *ecomp; + + if (!edev || !name || !name[0]) + return NULL; + + for (i = 0; i < edev->components; i++) { + ecomp = &edev->component[i]; + cname = dev_name(&ecomp->cdev); + if (ecomp->number != -1 && + cname && cname[0] && + !strcmp(cname, name)) + return ecomp; + } + + return NULL; +} + +static const struct attribute_group *enclosure_component_groups[]; + +/** + * enclosure_component_alloc - prepare a new enclosure component + * @edev: the enclosure to add the component + * @number: the device number + * @type: the type of component being added + * @name: an optional name to appear in sysfs (leave NULL if none) + * + * The name is optional for enclosures that give their components a unique + * name. If not, leave the field NULL and a name will be assigned. + * + * Returns a pointer to the enclosure component or an error. + */ +struct enclosure_component * +enclosure_component_alloc(struct enclosure_device *edev, + unsigned int number, + enum enclosure_component_type type, + const char *name) +{ + struct enclosure_component *ecomp; + struct device *cdev; + int i; + char newname[COMPONENT_NAME_SIZE]; + + if (number >= edev->components) + return ERR_PTR(-EINVAL); + + ecomp = &edev->component[number]; + + if (ecomp->number != -1) + return ERR_PTR(-EINVAL); + + ecomp->type = type; + ecomp->number = number; + cdev = &ecomp->cdev; + cdev->parent = get_device(&edev->edev); + + if (name && name[0]) { + /* Some hardware (e.g. enclosure in RX300 S6) has components + * with non unique names. Registering duplicates in sysfs + * will lead to warnings during bootup. So make the names + * unique by appending consecutive numbers -1, -2, ... */ + i = 1; + snprintf(newname, COMPONENT_NAME_SIZE, + "%s", name); + while (enclosure_component_find_by_name(edev, newname)) + snprintf(newname, COMPONENT_NAME_SIZE, + "%s-%i", name, i++); + dev_set_name(cdev, "%s", newname); + } else + dev_set_name(cdev, "%u", number); + + cdev->release = enclosure_component_release; + cdev->groups = enclosure_component_groups; + + return ecomp; +} +EXPORT_SYMBOL_GPL(enclosure_component_alloc); + +/** + * enclosure_component_register - publishes an initialized enclosure component + * @ecomp: component to add + * + * Returns 0 on successful registration, releases the component otherwise + */ +int enclosure_component_register(struct enclosure_component *ecomp) +{ + struct device *cdev; + int err; + + cdev = &ecomp->cdev; + err = device_register(cdev); + if (err) { + ecomp->number = -1; + put_device(cdev); + return err; + } + + return 0; +} +EXPORT_SYMBOL_GPL(enclosure_component_register); + +/** + * enclosure_add_device - add a device as being part of an enclosure + * @edev: the enclosure device being added to. + * @component: the number of the component + * @dev: the device being added + * + * Declares a real device to reside in slot (or identifier) @num of an + * enclosure. This will cause the relevant sysfs links to appear. + * This function may also be used to change a device associated with + * an enclosure without having to call enclosure_remove_device() in + * between. + * + * Returns zero on success or an error. + */ +int enclosure_add_device(struct enclosure_device *edev, int component, + struct device *dev) +{ + struct enclosure_component *cdev; + int err; + + if (!edev || component >= edev->components) + return -EINVAL; + + cdev = &edev->component[component]; + + if (cdev->dev == dev) + return -EEXIST; + + if (cdev->dev) { + enclosure_remove_links(cdev); + put_device(cdev->dev); + } + cdev->dev = get_device(dev); + err = enclosure_add_links(cdev); + if (err) { + put_device(cdev->dev); + cdev->dev = NULL; + } + return err; +} +EXPORT_SYMBOL_GPL(enclosure_add_device); + +/** + * enclosure_remove_device - remove a device from an enclosure + * @edev: the enclosure device + * @dev: device to remove/put + * + * Returns zero on success or an error. + * + */ +int enclosure_remove_device(struct enclosure_device *edev, struct device *dev) +{ + struct enclosure_component *cdev; + int i; + + if (!edev || !dev) + return -EINVAL; + + for (i = 0; i < edev->components; i++) { + cdev = &edev->component[i]; + if (cdev->dev == dev) { + enclosure_remove_links(cdev); + put_device(dev); + cdev->dev = NULL; + return 0; + } + } + return -ENODEV; +} +EXPORT_SYMBOL_GPL(enclosure_remove_device); + +/* + * sysfs pieces below + */ + +static ssize_t components_show(struct device *cdev, + struct device_attribute *attr, char *buf) +{ + struct enclosure_device *edev = to_enclosure_device(cdev); + + return sysfs_emit(buf, "%d\n", edev->components); +} +static DEVICE_ATTR_RO(components); + +static ssize_t id_show(struct device *cdev, + struct device_attribute *attr, + char *buf) +{ + struct enclosure_device *edev = to_enclosure_device(cdev); + + if (edev->cb->show_id) + return edev->cb->show_id(edev, buf); + return -EINVAL; +} +static DEVICE_ATTR_RO(id); + +static struct attribute *enclosure_class_attrs[] = { + &dev_attr_components.attr, + &dev_attr_id.attr, + NULL, +}; +ATTRIBUTE_GROUPS(enclosure_class); + +static struct class enclosure_class = { + .name = "enclosure", + .owner = THIS_MODULE, + .dev_release = enclosure_release, + .dev_groups = enclosure_class_groups, +}; + +static const char *const enclosure_status[] = { + [ENCLOSURE_STATUS_UNSUPPORTED] = "unsupported", + [ENCLOSURE_STATUS_OK] = "OK", + [ENCLOSURE_STATUS_CRITICAL] = "critical", + [ENCLOSURE_STATUS_NON_CRITICAL] = "non-critical", + [ENCLOSURE_STATUS_UNRECOVERABLE] = "unrecoverable", + [ENCLOSURE_STATUS_NOT_INSTALLED] = "not installed", + [ENCLOSURE_STATUS_UNKNOWN] = "unknown", + [ENCLOSURE_STATUS_UNAVAILABLE] = "unavailable", + [ENCLOSURE_STATUS_MAX] = NULL, +}; + +static const char *const enclosure_type[] = { + [ENCLOSURE_COMPONENT_DEVICE] = "device", + [ENCLOSURE_COMPONENT_ARRAY_DEVICE] = "array device", +}; + +static ssize_t get_component_fault(struct device *cdev, + struct device_attribute *attr, char *buf) +{ + struct enclosure_device *edev = to_enclosure_device(cdev->parent); + struct enclosure_component *ecomp = to_enclosure_component(cdev); + + if (edev->cb->get_fault) + edev->cb->get_fault(edev, ecomp); + return sysfs_emit(buf, "%d\n", ecomp->fault); +} + +static ssize_t set_component_fault(struct device *cdev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct enclosure_device *edev = to_enclosure_device(cdev->parent); + struct enclosure_component *ecomp = to_enclosure_component(cdev); + int val = simple_strtoul(buf, NULL, 0); + + if (edev->cb->set_fault) + edev->cb->set_fault(edev, ecomp, val); + return count; +} + +static ssize_t get_component_status(struct device *cdev, + struct device_attribute *attr,char *buf) +{ + struct enclosure_device *edev = to_enclosure_device(cdev->parent); + struct enclosure_component *ecomp = to_enclosure_component(cdev); + + if (edev->cb->get_status) + edev->cb->get_status(edev, ecomp); + return sysfs_emit(buf, "%s\n", enclosure_status[ecomp->status]); +} + +static ssize_t set_component_status(struct device *cdev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct enclosure_device *edev = to_enclosure_device(cdev->parent); + struct enclosure_component *ecomp = to_enclosure_component(cdev); + int i; + + for (i = 0; enclosure_status[i]; i++) { + if (strncmp(buf, enclosure_status[i], + strlen(enclosure_status[i])) == 0 && + (buf[strlen(enclosure_status[i])] == '\n' || + buf[strlen(enclosure_status[i])] == '\0')) + break; + } + + if (enclosure_status[i] && edev->cb->set_status) { + edev->cb->set_status(edev, ecomp, i); + return count; + } else + return -EINVAL; +} + +static ssize_t get_component_active(struct device *cdev, + struct device_attribute *attr, char *buf) +{ + struct enclosure_device *edev = to_enclosure_device(cdev->parent); + struct enclosure_component *ecomp = to_enclosure_component(cdev); + + if (edev->cb->get_active) + edev->cb->get_active(edev, ecomp); + return sysfs_emit(buf, "%d\n", ecomp->active); +} + +static ssize_t set_component_active(struct device *cdev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct enclosure_device *edev = to_enclosure_device(cdev->parent); + struct enclosure_component *ecomp = to_enclosure_component(cdev); + int val = simple_strtoul(buf, NULL, 0); + + if (edev->cb->set_active) + edev->cb->set_active(edev, ecomp, val); + return count; +} + +static ssize_t get_component_locate(struct device *cdev, + struct device_attribute *attr, char *buf) +{ + struct enclosure_device *edev = to_enclosure_device(cdev->parent); + struct enclosure_component *ecomp = to_enclosure_component(cdev); + + if (edev->cb->get_locate) + edev->cb->get_locate(edev, ecomp); + return sysfs_emit(buf, "%d\n", ecomp->locate); +} + +static ssize_t set_component_locate(struct device *cdev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct enclosure_device *edev = to_enclosure_device(cdev->parent); + struct enclosure_component *ecomp = to_enclosure_component(cdev); + int val = simple_strtoul(buf, NULL, 0); + + if (edev->cb->set_locate) + edev->cb->set_locate(edev, ecomp, val); + return count; +} + +static ssize_t get_component_power_status(struct device *cdev, + struct device_attribute *attr, + char *buf) +{ + struct enclosure_device *edev = to_enclosure_device(cdev->parent); + struct enclosure_component *ecomp = to_enclosure_component(cdev); + + if (edev->cb->get_power_status) + edev->cb->get_power_status(edev, ecomp); + + /* If still uninitialized, the callback failed or does not exist. */ + if (ecomp->power_status == -1) + return (edev->cb->get_power_status) ? -EIO : -ENOTTY; + + return sysfs_emit(buf, "%s\n", ecomp->power_status ? "on" : "off"); +} + +static ssize_t set_component_power_status(struct device *cdev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct enclosure_device *edev = to_enclosure_device(cdev->parent); + struct enclosure_component *ecomp = to_enclosure_component(cdev); + int val; + + if (strncmp(buf, "on", 2) == 0 && + (buf[2] == '\n' || buf[2] == '\0')) + val = 1; + else if (strncmp(buf, "off", 3) == 0 && + (buf[3] == '\n' || buf[3] == '\0')) + val = 0; + else + return -EINVAL; + + if (edev->cb->set_power_status) + edev->cb->set_power_status(edev, ecomp, val); + return count; +} + +static ssize_t get_component_type(struct device *cdev, + struct device_attribute *attr, char *buf) +{ + struct enclosure_component *ecomp = to_enclosure_component(cdev); + + return sysfs_emit(buf, "%s\n", enclosure_type[ecomp->type]); +} + +static ssize_t get_component_slot(struct device *cdev, + struct device_attribute *attr, char *buf) +{ + struct enclosure_component *ecomp = to_enclosure_component(cdev); + int slot; + + /* if the enclosure does not override then use 'number' as a stand-in */ + if (ecomp->slot >= 0) + slot = ecomp->slot; + else + slot = ecomp->number; + + return sysfs_emit(buf, "%d\n", slot); +} + +static DEVICE_ATTR(fault, S_IRUGO | S_IWUSR, get_component_fault, + set_component_fault); +static DEVICE_ATTR(status, S_IRUGO | S_IWUSR, get_component_status, + set_component_status); +static DEVICE_ATTR(active, S_IRUGO | S_IWUSR, get_component_active, + set_component_active); +static DEVICE_ATTR(locate, S_IRUGO | S_IWUSR, get_component_locate, + set_component_locate); +static DEVICE_ATTR(power_status, S_IRUGO | S_IWUSR, get_component_power_status, + set_component_power_status); +static DEVICE_ATTR(type, S_IRUGO, get_component_type, NULL); +static DEVICE_ATTR(slot, S_IRUGO, get_component_slot, NULL); + +static struct attribute *enclosure_component_attrs[] = { + &dev_attr_fault.attr, + &dev_attr_status.attr, + &dev_attr_active.attr, + &dev_attr_locate.attr, + &dev_attr_power_status.attr, + &dev_attr_type.attr, + &dev_attr_slot.attr, + NULL +}; +ATTRIBUTE_GROUPS(enclosure_component); + +static int __init enclosure_init(void) +{ + return class_register(&enclosure_class); +} + +static void __exit enclosure_exit(void) +{ + class_unregister(&enclosure_class); +} + +module_init(enclosure_init); +module_exit(enclosure_exit); + +MODULE_AUTHOR("James Bottomley"); +MODULE_DESCRIPTION("Enclosure Services"); +MODULE_LICENSE("GPL v2"); |