diff options
Diffstat (limited to 'drivers/of/base.c')
-rw-r--r-- | drivers/of/base.c | 451 |
1 files changed, 123 insertions, 328 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c index b9864806e9b8..d8574adf0d62 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -17,6 +17,7 @@ * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ +#include <linux/console.h> #include <linux/ctype.h> #include <linux/cpu.h> #include <linux/module.h> @@ -35,15 +36,17 @@ struct device_node *of_allnodes; EXPORT_SYMBOL(of_allnodes); struct device_node *of_chosen; struct device_node *of_aliases; -static struct device_node *of_stdout; +struct device_node *of_stdout; -static struct kset *of_kset; +struct kset *of_kset; /* - * Used to protect the of_aliases; but also overloaded to hold off addition of - * nodes to sysfs + * Used to protect the of_aliases, to hold off addition of nodes to sysfs. + * This mutex must be held whenever modifications are being made to the + * device tree. The of_{attach,detach}_node() and + * of_{add,remove,update}_property() helpers make sure this happens. */ -DEFINE_MUTEX(of_aliases_mutex); +DEFINE_MUTEX(of_mutex); /* use when traversing tree through the allnext, child, sibling, * or parent members of struct device_node. @@ -89,79 +92,7 @@ int __weak of_node_to_nid(struct device_node *np) } #endif -#if defined(CONFIG_OF_DYNAMIC) -/** - * of_node_get - Increment refcount of a node - * @node: Node to inc refcount, NULL is supported to - * simplify writing of callers - * - * Returns node. - */ -struct device_node *of_node_get(struct device_node *node) -{ - if (node) - kobject_get(&node->kobj); - return node; -} -EXPORT_SYMBOL(of_node_get); - -static inline struct device_node *kobj_to_device_node(struct kobject *kobj) -{ - return container_of(kobj, struct device_node, kobj); -} - -/** - * of_node_release - release a dynamically allocated node - * @kref: kref element of the node to be released - * - * In of_node_put() this function is passed to kref_put() - * as the destructor. - */ -static void of_node_release(struct kobject *kobj) -{ - struct device_node *node = kobj_to_device_node(kobj); - struct property *prop = node->properties; - - /* We should never be releasing nodes that haven't been detached. */ - if (!of_node_check_flag(node, OF_DETACHED)) { - pr_err("ERROR: Bad of_node_put() on %s\n", node->full_name); - dump_stack(); - return; - } - - if (!of_node_check_flag(node, OF_DYNAMIC)) - return; - - while (prop) { - struct property *next = prop->next; - kfree(prop->name); - kfree(prop->value); - kfree(prop); - prop = next; - - if (!prop) { - prop = node->deadprops; - node->deadprops = NULL; - } - } - kfree(node->full_name); - kfree(node->data); - kfree(node); -} - -/** - * of_node_put - Decrement refcount of a node - * @node: Node to dec refcount, NULL is supported to - * simplify writing of callers - * - */ -void of_node_put(struct device_node *node) -{ - if (node) - kobject_put(&node->kobj); -} -EXPORT_SYMBOL(of_node_put); -#else +#ifndef CONFIG_OF_DYNAMIC static void of_node_release(struct kobject *kobj) { /* Without CONFIG_OF_DYNAMIC, no nodes gets freed */ @@ -200,13 +131,16 @@ static const char *safe_name(struct kobject *kobj, const char *orig_name) return name; } -static int __of_add_property_sysfs(struct device_node *np, struct property *pp) +int __of_add_property_sysfs(struct device_node *np, struct property *pp) { int rc; /* Important: Don't leak passwords */ bool secure = strncmp(pp->name, "security-", 9) == 0; + if (!of_kset || !of_node_is_attached(np)) + return 0; + sysfs_bin_attr_init(&pp->attr); pp->attr.attr.name = safe_name(&np->kobj, pp->name); pp->attr.attr.mode = secure ? S_IRUSR : S_IRUGO; @@ -218,12 +152,15 @@ static int __of_add_property_sysfs(struct device_node *np, struct property *pp) return rc; } -static int __of_node_add(struct device_node *np) +int __of_attach_node_sysfs(struct device_node *np) { const char *name; struct property *pp; int rc; + if (!of_kset) + return 0; + np->kobj.kset = of_kset; if (!np->parent) { /* Nodes without parents are new top level trees */ @@ -245,59 +182,20 @@ static int __of_node_add(struct device_node *np) return 0; } -int of_node_add(struct device_node *np) -{ - int rc = 0; - - BUG_ON(!of_node_is_initialized(np)); - - /* - * Grab the mutex here so that in a race condition between of_init() and - * of_node_add(), node addition will still be consistent. - */ - mutex_lock(&of_aliases_mutex); - if (of_kset) - rc = __of_node_add(np); - else - /* This scenario may be perfectly valid, but report it anyway */ - pr_info("of_node_add(%s) before of_init()\n", np->full_name); - mutex_unlock(&of_aliases_mutex); - return rc; -} - -#if defined(CONFIG_OF_DYNAMIC) -static void of_node_remove(struct device_node *np) -{ - struct property *pp; - - BUG_ON(!of_node_is_initialized(np)); - - /* only remove properties if on sysfs */ - if (of_node_is_attached(np)) { - for_each_property_of_node(np, pp) - sysfs_remove_bin_file(&np->kobj, &pp->attr); - kobject_del(&np->kobj); - } - - /* finally remove the kobj_init ref */ - of_node_put(np); -} -#endif - static int __init of_init(void) { struct device_node *np; /* Create the kset, and register existing nodes */ - mutex_lock(&of_aliases_mutex); + mutex_lock(&of_mutex); of_kset = kset_create_and_add("devicetree", NULL, firmware_kobj); if (!of_kset) { - mutex_unlock(&of_aliases_mutex); + mutex_unlock(&of_mutex); return -ENOMEM; } for_each_of_allnodes(np) - __of_node_add(np); - mutex_unlock(&of_aliases_mutex); + __of_attach_node_sysfs(np); + mutex_unlock(&of_mutex); /* Symlink in /proc as required by userspace ABI */ if (of_allnodes) @@ -369,8 +267,8 @@ EXPORT_SYMBOL(of_find_all_nodes); * Find a property with a given name for a given node * and return the value. */ -static const void *__of_get_property(const struct device_node *np, - const char *name, int *lenp) +const void *__of_get_property(const struct device_node *np, + const char *name, int *lenp) { struct property *pp = __of_find_property(np, name, lenp); @@ -1748,32 +1646,10 @@ int of_count_phandle_with_args(const struct device_node *np, const char *list_na } EXPORT_SYMBOL(of_count_phandle_with_args); -#if defined(CONFIG_OF_DYNAMIC) -static int of_property_notify(int action, struct device_node *np, - struct property *prop) -{ - struct of_prop_reconfig pr; - - /* only call notifiers if the node is attached */ - if (!of_node_is_attached(np)) - return 0; - - pr.dn = np; - pr.prop = prop; - return of_reconfig_notify(action, &pr); -} -#else -static int of_property_notify(int action, struct device_node *np, - struct property *prop) -{ - return 0; -} -#endif - /** * __of_add_property - Add a property to a node without lock operations */ -static int __of_add_property(struct device_node *np, struct property *prop) +int __of_add_property(struct device_node *np, struct property *prop) { struct property **next; @@ -1799,22 +1675,49 @@ int of_add_property(struct device_node *np, struct property *prop) unsigned long flags; int rc; - rc = of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop); - if (rc) - return rc; + mutex_lock(&of_mutex); raw_spin_lock_irqsave(&devtree_lock, flags); rc = __of_add_property(np, prop); raw_spin_unlock_irqrestore(&devtree_lock, flags); - if (rc) - return rc; - if (of_node_is_attached(np)) + if (!rc) __of_add_property_sysfs(np, prop); + mutex_unlock(&of_mutex); + + if (!rc) + of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop, NULL); + return rc; } +int __of_remove_property(struct device_node *np, struct property *prop) +{ + struct property **next; + + for (next = &np->properties; *next; next = &(*next)->next) { + if (*next == prop) + break; + } + if (*next == NULL) + return -ENODEV; + + /* found the node */ + *next = prop->next; + prop->next = np->deadprops; + np->deadprops = prop; + + return 0; +} + +void __of_remove_property_sysfs(struct device_node *np, struct property *prop) +{ + /* at early boot, bail here and defer setup to of_init() */ + if (of_kset && of_node_is_attached(np)) + sysfs_remove_bin_file(&np->kobj, &prop->attr); +} + /** * of_remove_property - Remove a property from a node. * @@ -1825,211 +1728,98 @@ int of_add_property(struct device_node *np, struct property *prop) */ int of_remove_property(struct device_node *np, struct property *prop) { - struct property **next; unsigned long flags; - int found = 0; int rc; - rc = of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop); - if (rc) - return rc; + mutex_lock(&of_mutex); raw_spin_lock_irqsave(&devtree_lock, flags); - next = &np->properties; - while (*next) { - if (*next == prop) { - /* found the node */ - *next = prop->next; - prop->next = np->deadprops; - np->deadprops = prop; - found = 1; - break; - } - next = &(*next)->next; - } + rc = __of_remove_property(np, prop); raw_spin_unlock_irqrestore(&devtree_lock, flags); - if (!found) - return -ENODEV; + if (!rc) + __of_remove_property_sysfs(np, prop); - /* at early boot, bail hear and defer setup to of_init() */ - if (!of_kset) - return 0; + mutex_unlock(&of_mutex); - sysfs_remove_bin_file(&np->kobj, &prop->attr); + if (!rc) + of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop, NULL); - return 0; + return rc; } -/* - * of_update_property - Update a property in a node, if the property does - * not exist, add it. - * - * Note that we don't actually remove it, since we have given out - * who-knows-how-many pointers to the data using get-property. - * Instead we just move the property to the "dead properties" list, - * and add the new property to the property list - */ -int of_update_property(struct device_node *np, struct property *newprop) +int __of_update_property(struct device_node *np, struct property *newprop, + struct property **oldpropp) { struct property **next, *oldprop; - unsigned long flags; - int rc; - - rc = of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop); - if (rc) - return rc; - if (!newprop->name) - return -EINVAL; + for (next = &np->properties; *next; next = &(*next)->next) { + if (of_prop_cmp((*next)->name, newprop->name) == 0) + break; + } + *oldpropp = oldprop = *next; - raw_spin_lock_irqsave(&devtree_lock, flags); - next = &np->properties; - oldprop = __of_find_property(np, newprop->name, NULL); - if (!oldprop) { - /* add the new node */ - rc = __of_add_property(np, newprop); - } else while (*next) { + if (oldprop) { /* replace the node */ - if (*next == oldprop) { - newprop->next = oldprop->next; - *next = newprop; - oldprop->next = np->deadprops; - np->deadprops = oldprop; - break; - } - next = &(*next)->next; + newprop->next = oldprop->next; + *next = newprop; + oldprop->next = np->deadprops; + np->deadprops = oldprop; + } else { + /* new node */ + newprop->next = NULL; + *next = newprop; } - raw_spin_unlock_irqrestore(&devtree_lock, flags); - if (rc) - return rc; + return 0; +} + +void __of_update_property_sysfs(struct device_node *np, struct property *newprop, + struct property *oldprop) +{ /* At early boot, bail out and defer setup to of_init() */ if (!of_kset) - return 0; + return; - /* Update the sysfs attribute */ if (oldprop) sysfs_remove_bin_file(&np->kobj, &oldprop->attr); __of_add_property_sysfs(np, newprop); - - return 0; } -#if defined(CONFIG_OF_DYNAMIC) /* - * Support for dynamic device trees. + * of_update_property - Update a property in a node, if the property does + * not exist, add it. * - * On some platforms, the device tree can be manipulated at runtime. - * The routines in this section support adding, removing and changing - * device tree nodes. - */ - -static BLOCKING_NOTIFIER_HEAD(of_reconfig_chain); - -int of_reconfig_notifier_register(struct notifier_block *nb) -{ - return blocking_notifier_chain_register(&of_reconfig_chain, nb); -} -EXPORT_SYMBOL_GPL(of_reconfig_notifier_register); - -int of_reconfig_notifier_unregister(struct notifier_block *nb) -{ - return blocking_notifier_chain_unregister(&of_reconfig_chain, nb); -} -EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister); - -int of_reconfig_notify(unsigned long action, void *p) -{ - int rc; - - rc = blocking_notifier_call_chain(&of_reconfig_chain, action, p); - return notifier_to_errno(rc); -} - -/** - * of_attach_node - Plug a device node into the tree and global list. + * Note that we don't actually remove it, since we have given out + * who-knows-how-many pointers to the data using get-property. + * Instead we just move the property to the "dead properties" list, + * and add the new property to the property list */ -int of_attach_node(struct device_node *np) +int of_update_property(struct device_node *np, struct property *newprop) { + struct property *oldprop; unsigned long flags; int rc; - rc = of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, np); - if (rc) - return rc; - - raw_spin_lock_irqsave(&devtree_lock, flags); - np->sibling = np->parent->child; - np->allnext = np->parent->allnext; - np->parent->allnext = np; - np->parent->child = np; - of_node_clear_flag(np, OF_DETACHED); - raw_spin_unlock_irqrestore(&devtree_lock, flags); - - of_node_add(np); - return 0; -} - -/** - * of_detach_node - "Unplug" a node from the device tree. - * - * The caller must hold a reference to the node. The memory associated with - * the node is not freed until its refcount goes to zero. - */ -int of_detach_node(struct device_node *np) -{ - struct device_node *parent; - unsigned long flags; - int rc = 0; + if (!newprop->name) + return -EINVAL; - rc = of_reconfig_notify(OF_RECONFIG_DETACH_NODE, np); - if (rc) - return rc; + mutex_lock(&of_mutex); raw_spin_lock_irqsave(&devtree_lock, flags); + rc = __of_update_property(np, newprop, &oldprop); + raw_spin_unlock_irqrestore(&devtree_lock, flags); - if (of_node_check_flag(np, OF_DETACHED)) { - /* someone already detached it */ - raw_spin_unlock_irqrestore(&devtree_lock, flags); - return rc; - } - - parent = np->parent; - if (!parent) { - raw_spin_unlock_irqrestore(&devtree_lock, flags); - return rc; - } + if (!rc) + __of_update_property_sysfs(np, newprop, oldprop); - if (of_allnodes == np) - of_allnodes = np->allnext; - else { - struct device_node *prev; - for (prev = of_allnodes; - prev->allnext != np; - prev = prev->allnext) - ; - prev->allnext = np->allnext; - } + mutex_unlock(&of_mutex); - if (parent->child == np) - parent->child = np->sibling; - else { - struct device_node *prevsib; - for (prevsib = np->parent->child; - prevsib->sibling != np; - prevsib = prevsib->sibling) - ; - prevsib->sibling = np->sibling; - } - - of_node_set_flag(np, OF_DETACHED); - raw_spin_unlock_irqrestore(&devtree_lock, flags); + if (!rc) + of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop, oldprop); - of_node_remove(np); return rc; } -#endif /* defined(CONFIG_OF_DYNAMIC) */ static void of_alias_add(struct alias_prop *ap, struct device_node *np, int id, const char *stem, int stem_len) @@ -2062,9 +1852,12 @@ void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align)) of_chosen = of_find_node_by_path("/chosen@0"); if (of_chosen) { + /* linux,stdout-path and /aliases/stdout are for legacy compatibility */ const char *name = of_get_property(of_chosen, "stdout-path", NULL); if (!name) name = of_get_property(of_chosen, "linux,stdout-path", NULL); + if (IS_ENABLED(CONFIG_PPC) && !name) + name = of_get_property(of_aliases, "stdout", NULL); if (name) of_stdout = of_find_node_by_path(name); } @@ -2122,7 +1915,7 @@ int of_alias_get_id(struct device_node *np, const char *stem) struct alias_prop *app; int id = -ENODEV; - mutex_lock(&of_aliases_mutex); + mutex_lock(&of_mutex); list_for_each_entry(app, &aliases_lookup, link) { if (strcmp(app->stem, stem) != 0) continue; @@ -2132,7 +1925,7 @@ int of_alias_get_id(struct device_node *np, const char *stem) break; } } - mutex_unlock(&of_aliases_mutex); + mutex_unlock(&of_mutex); return id; } @@ -2180,20 +1973,22 @@ const char *of_prop_next_string(struct property *prop, const char *cur) EXPORT_SYMBOL_GPL(of_prop_next_string); /** - * of_device_is_stdout_path - check if a device node matches the - * linux,stdout-path property - * - * Check if this device node matches the linux,stdout-path property - * in the chosen node. return true if yes, false otherwise. + * of_console_check() - Test and setup console for DT setup + * @dn - Pointer to device node + * @name - Name to use for preferred console without index. ex. "ttyS" + * @index - Index to use for preferred console. + * + * Check if the given device node matches the stdout-path property in the + * /chosen node. If it does then register it as the preferred console and return + * TRUE. Otherwise return FALSE. */ -int of_device_is_stdout_path(struct device_node *dn) +bool of_console_check(struct device_node *dn, char *name, int index) { - if (!of_stdout) + if (!dn || dn != of_stdout || console_set_on_cmdline) return false; - - return of_stdout == dn; + return add_preferred_console(name, index, NULL); } -EXPORT_SYMBOL_GPL(of_device_is_stdout_path); +EXPORT_SYMBOL_GPL(of_console_check); /** * of_find_next_cache_node - Find a node's subsidiary cache |