diff options
Diffstat (limited to 'drivers/of/base.c')
| -rw-r--r-- | drivers/of/base.c | 999 |
1 files changed, 644 insertions, 355 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c index b60f9a77ab03..f0668356867b 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -18,10 +18,13 @@ * 2 of the License, or (at your option) any later version. */ #include <linux/ctype.h> +#include <linux/cpu.h> #include <linux/module.h> #include <linux/of.h> +#include <linux/of_graph.h> #include <linux/spinlock.h> #include <linux/slab.h> +#include <linux/string.h> #include <linux/proc_fs.h> #include "of_private.h" @@ -32,8 +35,17 @@ 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; -DEFINE_MUTEX(of_aliases_mutex); +struct kset *of_kset; + +/* + * 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_mutex); /* use when traversing tree through the allnext, child, sibling, * or parent members of struct device_node. @@ -72,80 +84,117 @@ int of_n_size_cells(struct device_node *np) } EXPORT_SYMBOL(of_n_size_cells); -#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) +#ifndef CONFIG_OF_DYNAMIC +static void of_node_release(struct kobject *kobj) { - if (node) - kref_get(&node->kref); - return node; + /* Without CONFIG_OF_DYNAMIC, no nodes gets freed */ } -EXPORT_SYMBOL(of_node_get); +#endif /* CONFIG_OF_DYNAMIC */ -static inline struct device_node *kref_to_device_node(struct kref *kref) +struct kobj_type of_node_ktype = { + .release = of_node_release, +}; + +static ssize_t of_node_property_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, char *buf, + loff_t offset, size_t count) { - return container_of(kref, struct device_node, kref); + struct property *pp = container_of(bin_attr, struct property, attr); + return memory_read_from_buffer(buf, count, &offset, pp->value, pp->length); } -/** - * 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 kref *kref) +static const char *safe_name(struct kobject *kobj, const char *orig_name) { - struct device_node *node = kref_to_device_node(kref); - 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(); - kref_init(&node->kref); - return; + const char *name = orig_name; + struct sysfs_dirent *kn; + int i = 0; + + /* don't be a hero. After 16 tries give up */ + while (i < 16 && (kn = sysfs_get_dirent(kobj->sd, NULL, name))) { + sysfs_put(kn); + if (name != orig_name) + kfree(name); + name = kasprintf(GFP_KERNEL, "%s#%i", orig_name, ++i); } - if (!of_node_check_flag(node, OF_DYNAMIC)) - return; + if (name != orig_name) + pr_warn("device-tree: Duplicate name in %s, renamed to \"%s\"\n", + kobject_name(kobj), name); + return name; +} - while (prop) { - struct property *next = prop->next; - kfree(prop->name); - kfree(prop->value); - kfree(prop); - prop = next; +int __of_add_property_sysfs(struct device_node *np, struct property *pp) +{ + int rc; - if (!prop) { - prop = node->deadprops; - node->deadprops = NULL; - } + /* 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; + pp->attr.size = secure ? 0 : pp->length; + pp->attr.read = of_node_property_read; + + rc = sysfs_create_bin_file(&np->kobj, &pp->attr); + WARN(rc, "error adding attribute %s to node %s\n", pp->name, np->full_name); + return rc; +} + +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 */ + rc = kobject_add(&np->kobj, NULL, safe_name(&of_kset->kobj, "base")); + } else { + name = safe_name(&np->parent->kobj, kbasename(np->full_name)); + if (!name || !name[0]) + return -EINVAL; + + rc = kobject_add(&np->kobj, &np->parent->kobj, "%s", name); } - kfree(node->full_name); - kfree(node->data); - kfree(node); + if (rc) + return rc; + + for_each_property_of_node(np, pp) + __of_add_property_sysfs(np, pp); + + return 0; } -/** - * 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) +static int __init of_init(void) { - if (node) - kref_put(&node->kref, of_node_release); + struct device_node *np; + + /* Create the kset, and register existing nodes */ + mutex_lock(&of_mutex); + of_kset = kset_create_and_add("devicetree", NULL, firmware_kobj); + if (!of_kset) { + mutex_unlock(&of_mutex); + return -ENOMEM; + } + for_each_of_allnodes(np) + __of_attach_node_sysfs(np); + mutex_unlock(&of_mutex); + + /* Symlink in /proc as required by userspace ABI */ + if (of_allnodes) + proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base"); + + return 0; } -EXPORT_SYMBOL(of_node_put); -#endif /* CONFIG_OF_DYNAMIC */ +core_initcall(of_init); static struct property *__of_find_property(const struct device_node *np, const char *name, int *lenp) @@ -209,8 +258,8 @@ 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); @@ -230,6 +279,100 @@ const void *of_get_property(const struct device_node *np, const char *name, } EXPORT_SYMBOL(of_get_property); +/* + * arch_match_cpu_phys_id - Match the given logical CPU and physical id + * + * @cpu: logical cpu index of a core/thread + * @phys_id: physical identifier of a core/thread + * + * CPU logical to physical index mapping is architecture specific. + * However this __weak function provides a default match of physical + * id to logical cpu index. phys_id provided here is usually values read + * from the device tree which must match the hardware internal registers. + * + * Returns true if the physical identifier and the logical cpu index + * correspond to the same core/thread, false otherwise. + */ +bool __weak arch_match_cpu_phys_id(int cpu, u64 phys_id) +{ + return (u32)phys_id == cpu; +} + +/** + * Checks if the given "prop_name" property holds the physical id of the + * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not + * NULL, local thread number within the core is returned in it. + */ +static bool __of_find_n_match_cpu_property(struct device_node *cpun, + const char *prop_name, int cpu, unsigned int *thread) +{ + const __be32 *cell; + int ac, prop_len, tid; + u64 hwid; + + ac = of_n_addr_cells(cpun); + cell = of_get_property(cpun, prop_name, &prop_len); + if (!cell) + return false; + prop_len /= sizeof(*cell); + for (tid = 0; tid < prop_len; tid++) { + hwid = of_read_number(cell, ac); + if (arch_match_cpu_phys_id(cpu, hwid)) { + if (thread) + *thread = tid; + return true; + } + cell += ac; + } + return false; +} + +/** + * of_get_cpu_node - Get device node associated with the given logical CPU + * + * @cpu: CPU number(logical index) for which device node is required + * @thread: if not NULL, local thread number within the physical core is + * returned + * + * The main purpose of this function is to retrieve the device node for the + * given logical CPU index. It should be used to initialize the of_node in + * cpu device. Once of_node in cpu device is populated, all the further + * references can use that instead. + * + * CPU logical to physical index mapping is architecture specific and is built + * before booting secondary cores. This function uses arch_match_cpu_phys_id + * which can be overridden by architecture specific implementation. + * + * Returns a node pointer for the logical cpu if found, else NULL. + */ +struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) +{ + struct device_node *cpun, *cpus; + + cpus = of_find_node_by_path("/cpus"); + if (!cpus) { + pr_warn("Missing cpus node, bailing out\n"); + return NULL; + } + + for_each_child_of_node(cpus, cpun) { + if (of_node_cmp(cpun->type, "cpu")) + continue; + /* Check for non-standard "ibm,ppc-interrupt-server#s" property + * for thread ids on PowerPC. If it doesn't exist fallback to + * standard "reg" property. + */ + if (IS_ENABLED(CONFIG_PPC) && + __of_find_n_match_cpu_property(cpun, + "ibm,ppc-interrupt-server#s", cpu, thread)) + return cpun; + if (__of_find_n_match_cpu_property(cpun, "reg", cpu, thread)) + return cpun; + } + return NULL; +} +EXPORT_SYMBOL(of_get_cpu_node); + /** Checks if the given "compat" string matches one of the strings in * the device's "compatible" property */ @@ -750,6 +893,38 @@ struct device_node *of_find_node_by_phandle(phandle handle) EXPORT_SYMBOL(of_find_node_by_phandle); /** + * of_property_count_elems_of_size - Count the number of elements in a property + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @elem_size: size of the individual element + * + * Search for a property in a device node and count the number of elements of + * size elem_size in it. Returns number of elements on sucess, -EINVAL if the + * property does not exist or its length does not match a multiple of elem_size + * and -ENODATA if the property does not have a value. + */ +int of_property_count_elems_of_size(const struct device_node *np, + const char *propname, int elem_size) +{ + struct property *prop = of_find_property(np, propname, NULL); + + if (!prop) + return -EINVAL; + if (!prop->value) + return -ENODATA; + + if (prop->length % elem_size != 0) { + pr_err("size of %s in node %s is not a multiple of %d\n", + propname, np->full_name, elem_size); + return -EINVAL; + } + + return prop->length / elem_size; +} +EXPORT_SYMBOL_GPL(of_property_count_elems_of_size); + +/** * of_find_property_value_of_size * * @np: device node from which the property value is to be read. @@ -1036,65 +1211,10 @@ int of_property_read_string_helper(struct device_node *np, const char *propname, } EXPORT_SYMBOL_GPL(of_property_read_string_helper); -/** - * of_parse_phandle - Resolve a phandle property to a device_node pointer - * @np: Pointer to device node holding phandle property - * @phandle_name: Name of property holding a phandle value - * @index: For properties holding a table of phandles, this is the index into - * the table - * - * Returns the device_node pointer with refcount incremented. Use - * of_node_put() on it when done. - */ -struct device_node *of_parse_phandle(const struct device_node *np, - const char *phandle_name, int index) -{ - const __be32 *phandle; - int size; - - phandle = of_get_property(np, phandle_name, &size); - if ((!phandle) || (size < sizeof(*phandle) * (index + 1))) - return NULL; - - return of_find_node_by_phandle(be32_to_cpup(phandle + index)); -} -EXPORT_SYMBOL(of_parse_phandle); - -/** - * of_parse_phandle_with_args() - Find a node pointed by phandle in a list - * @np: pointer to a device tree node containing a list - * @list_name: property name that contains a list - * @cells_name: property name that specifies phandles' arguments count - * @index: index of a phandle to parse out - * @out_args: optional pointer to output arguments structure (will be filled) - * - * This function is useful to parse lists of phandles and their arguments. - * Returns 0 on success and fills out_args, on error returns appropriate - * errno value. - * - * Caller is responsible to call of_node_put() on the returned out_args->node - * pointer. - * - * Example: - * - * phandle1: node1 { - * #list-cells = <2>; - * } - * - * phandle2: node2 { - * #list-cells = <1>; - * } - * - * node3 { - * list = <&phandle1 1 2 &phandle2 3>; - * } - * - * To get a device_node of the `node2' node you may call this: - * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args); - */ static int __of_parse_phandle_with_args(const struct device_node *np, const char *list_name, - const char *cells_name, int index, + const char *cells_name, + int cell_count, int index, struct of_phandle_args *out_args) { const __be32 *list, *list_end; @@ -1122,19 +1242,32 @@ static int __of_parse_phandle_with_args(const struct device_node *np, if (phandle) { /* * Find the provider node and parse the #*-cells - * property to determine the argument length + * property to determine the argument length. + * + * This is not needed if the cell count is hard-coded + * (i.e. cells_name not set, but cell_count is set), + * except when we're going to return the found node + * below. */ - node = of_find_node_by_phandle(phandle); - if (!node) { - pr_err("%s: could not find phandle\n", - np->full_name); - goto err; + if (cells_name || cur_index == index) { + node = of_find_node_by_phandle(phandle); + if (!node) { + pr_err("%s: could not find phandle\n", + np->full_name); + goto err; + } } - if (of_property_read_u32(node, cells_name, &count)) { - pr_err("%s: could not get %s for %s\n", - np->full_name, cells_name, - node->full_name); - goto err; + + if (cells_name) { + if (of_property_read_u32(node, cells_name, + &count)) { + pr_err("%s: could not get %s for %s\n", + np->full_name, cells_name, + node->full_name); + goto err; + } + } else { + count = cell_count; } /* @@ -1194,17 +1327,117 @@ static int __of_parse_phandle_with_args(const struct device_node *np, return rc; } +/** + * of_parse_phandle - Resolve a phandle property to a device_node pointer + * @np: Pointer to device node holding phandle property + * @phandle_name: Name of property holding a phandle value + * @index: For properties holding a table of phandles, this is the index into + * the table + * + * Returns the device_node pointer with refcount incremented. Use + * of_node_put() on it when done. + */ +struct device_node *of_parse_phandle(const struct device_node *np, + const char *phandle_name, int index) +{ + struct of_phandle_args args; + + if (index < 0) + return NULL; + + if (__of_parse_phandle_with_args(np, phandle_name, NULL, 0, + index, &args)) + return NULL; + + return args.np; +} +EXPORT_SYMBOL(of_parse_phandle); + +/** + * of_parse_phandle_with_args() - Find a node pointed by phandle in a list + * @np: pointer to a device tree node containing a list + * @list_name: property name that contains a list + * @cells_name: property name that specifies phandles' arguments count + * @index: index of a phandle to parse out + * @out_args: optional pointer to output arguments structure (will be filled) + * + * This function is useful to parse lists of phandles and their arguments. + * Returns 0 on success and fills out_args, on error returns appropriate + * errno value. + * + * Caller is responsible to call of_node_put() on the returned out_args->node + * pointer. + * + * Example: + * + * phandle1: node1 { + * #list-cells = <2>; + * } + * + * phandle2: node2 { + * #list-cells = <1>; + * } + * + * node3 { + * list = <&phandle1 1 2 &phandle2 3>; + * } + * + * To get a device_node of the `node2' node you may call this: + * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args); + */ int of_parse_phandle_with_args(const struct device_node *np, const char *list_name, const char *cells_name, int index, struct of_phandle_args *out_args) { if (index < 0) return -EINVAL; - return __of_parse_phandle_with_args(np, list_name, cells_name, index, out_args); + return __of_parse_phandle_with_args(np, list_name, cells_name, 0, + index, out_args); } EXPORT_SYMBOL(of_parse_phandle_with_args); /** + * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list + * @np: pointer to a device tree node containing a list + * @list_name: property name that contains a list + * @cell_count: number of argument cells following the phandle + * @index: index of a phandle to parse out + * @out_args: optional pointer to output arguments structure (will be filled) + * + * This function is useful to parse lists of phandles and their arguments. + * Returns 0 on success and fills out_args, on error returns appropriate + * errno value. + * + * Caller is responsible to call of_node_put() on the returned out_args->node + * pointer. + * + * Example: + * + * phandle1: node1 { + * } + * + * phandle2: node2 { + * } + * + * node3 { + * list = <&phandle1 0 2 &phandle2 2 3>; + * } + * + * To get a device_node of the `node2' node you may call this: + * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args); + */ +int of_parse_phandle_with_fixed_args(const struct device_node *np, + const char *list_name, int cell_count, + int index, struct of_phandle_args *out_args) +{ + if (index < 0) + return -EINVAL; + return __of_parse_phandle_with_args(np, list_name, NULL, cell_count, + index, out_args); +} +EXPORT_SYMBOL(of_parse_phandle_with_fixed_args); + +/** * of_count_phandle_with_args() - Find the number of phandles references in a property * @np: pointer to a device tree node containing a list * @list_name: property name that contains a list @@ -1222,305 +1455,185 @@ EXPORT_SYMBOL(of_parse_phandle_with_args); int of_count_phandle_with_args(const struct device_node *np, const char *list_name, const char *cells_name) { - return __of_parse_phandle_with_args(np, list_name, cells_name, -1, NULL); + return __of_parse_phandle_with_args(np, list_name, cells_name, 0, -1, + NULL); } 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; - - 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 + * __of_add_property - Add a property to a node without lock operations */ -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; - unsigned long flags; - int rc; - - rc = of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop); - if (rc) - return rc; prop->next = NULL; - raw_spin_lock_irqsave(&devtree_lock, flags); next = &np->properties; while (*next) { - if (strcmp(prop->name, (*next)->name) == 0) { + if (strcmp(prop->name, (*next)->name) == 0) /* duplicate ! don't insert it */ - raw_spin_unlock_irqrestore(&devtree_lock, flags); - return -1; - } + return -EEXIST; + next = &(*next)->next; } *next = prop; - raw_spin_unlock_irqrestore(&devtree_lock, flags); - -#ifdef CONFIG_PROC_DEVICETREE - /* try to add to proc as well if it was initialized */ - if (np->pde) - proc_device_tree_add_prop(np->pde, prop); -#endif /* CONFIG_PROC_DEVICETREE */ return 0; } /** - * of_remove_property - Remove a property from a node. - * - * 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, so it won't be found any more. + * of_add_property - Add a property to a node */ -int of_remove_property(struct device_node *np, struct property *prop) +int of_add_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_add_property(np, prop); raw_spin_unlock_irqrestore(&devtree_lock, flags); - if (!found) - return -ENODEV; + if (!rc) + __of_add_property_sysfs(np, prop); -#ifdef CONFIG_PROC_DEVICETREE - /* try to remove the proc node as well */ - if (np->pde) - proc_device_tree_remove_prop(np->pde, prop); -#endif /* CONFIG_PROC_DEVICETREE */ + mutex_unlock(&of_mutex); - return 0; + if (!rc) + of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop, NULL); + + 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_remove_property(struct device_node *np, struct property *prop) { - struct property **next, *oldprop; - unsigned long flags; - int rc, found = 0; - - rc = of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop); - if (rc) - return rc; - - if (!newprop->name) - return -EINVAL; - - oldprop = of_find_property(np, newprop->name, NULL); - if (!oldprop) - return of_add_property(np, newprop); + struct property **next; - raw_spin_lock_irqsave(&devtree_lock, flags); - next = &np->properties; - while (*next) { - if (*next == oldprop) { - /* found the node */ - newprop->next = oldprop->next; - *next = newprop; - oldprop->next = np->deadprops; - np->deadprops = oldprop; - found = 1; + for (next = &np->properties; *next; next = &(*next)->next) { + if (*next == prop) break; - } - next = &(*next)->next; } - raw_spin_unlock_irqrestore(&devtree_lock, flags); - - if (!found) + if (*next == NULL) return -ENODEV; -#ifdef CONFIG_PROC_DEVICETREE - /* try to add to proc as well if it was initialized */ - if (np->pde) - proc_device_tree_update_prop(np->pde, newprop, oldprop); -#endif /* CONFIG_PROC_DEVICETREE */ + /* found the node */ + *next = prop->next; + prop->next = np->deadprops; + np->deadprops = prop; return 0; } -#if defined(CONFIG_OF_DYNAMIC) -/* - * Support for dynamic device trees. - * - * 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); -} - -#ifdef CONFIG_PROC_DEVICETREE -static void of_add_proc_dt_entry(struct device_node *dn) -{ - struct proc_dir_entry *ent; - - ent = proc_mkdir(strrchr(dn->full_name, '/') + 1, dn->parent->pde); - if (ent) - proc_device_tree_add_node(dn, ent); -} -#else -static void of_add_proc_dt_entry(struct device_node *dn) +void __of_remove_property_sysfs(struct device_node *np, struct property *prop) { - return; + /* 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); } -#endif /** - * of_attach_node - Plug a device node into the tree and global list. + * of_remove_property - Remove a property from a node. + * + * 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, so it won't be found any more. */ -int of_attach_node(struct device_node *np) +int of_remove_property(struct device_node *np, struct property *prop) { unsigned long flags; int rc; - rc = of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, np); - if (rc) - return rc; + mutex_lock(&of_mutex); raw_spin_lock_irqsave(&devtree_lock, flags); - np->sibling = np->parent->child; - np->allnext = of_allnodes; - np->parent->child = np; - of_allnodes = np; + rc = __of_remove_property(np, prop); raw_spin_unlock_irqrestore(&devtree_lock, flags); - of_add_proc_dt_entry(np); - return 0; + if (!rc) + __of_remove_property_sysfs(np, prop); + + mutex_unlock(&of_mutex); + + if (!rc) + of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop, NULL); + + return rc; } -#ifdef CONFIG_PROC_DEVICETREE -static void of_remove_proc_dt_entry(struct device_node *dn) +int __of_update_property(struct device_node *np, struct property *newprop, + struct property **oldpropp) { - proc_remove(dn->pde); + struct property **next, *oldprop; + + for (next = &np->properties; *next; next = &(*next)->next) { + if (of_prop_cmp((*next)->name, newprop->name) == 0) + break; + } + *oldpropp = oldprop = *next; + + if (oldprop) { + /* replace the node */ + newprop->next = oldprop->next; + *next = newprop; + oldprop->next = np->deadprops; + np->deadprops = oldprop; + } else { + /* new node */ + newprop->next = NULL; + *next = newprop; + } + + return 0; } -#else -static void of_remove_proc_dt_entry(struct device_node *dn) + +void __of_update_property_sysfs(struct device_node *np, struct property *newprop, + struct property *oldprop) { - return; + /* At early boot, bail out and defer setup to of_init() */ + if (!of_kset) + return; + + if (oldprop) + sysfs_remove_bin_file(&np->kobj, &oldprop->attr); + __of_add_property_sysfs(np, newprop); } -#endif -/** - * of_detach_node - "Unplug" a node from the device tree. +/* + * of_update_property - Update a property in a node, if the property does + * not exist, add it. * - * The caller must hold a reference to the node. The memory associated with - * the node is not freed until its refcount goes to zero. + * 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_detach_node(struct device_node *np) +int of_update_property(struct device_node *np, struct property *newprop) { - struct device_node *parent; + struct property *oldprop; unsigned long flags; - int rc = 0; + int rc; - rc = of_reconfig_notify(OF_RECONFIG_DETACH_NODE, np); - if (rc) - return rc; + if (!newprop->name) + return -EINVAL; - raw_spin_lock_irqsave(&devtree_lock, flags); + mutex_lock(&of_mutex); - 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; - } + raw_spin_lock_irqsave(&devtree_lock, flags); + rc = __of_update_property(np, newprop, &oldprop); + raw_spin_unlock_irqrestore(&devtree_lock, flags); - 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; - } + if (!rc) + __of_update_property_sysfs(np, newprop, oldprop); - 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; - } + mutex_unlock(&of_mutex); - 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_remove_proc_dt_entry(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) @@ -1551,6 +1664,15 @@ void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align)) of_chosen = of_find_node_by_path("/chosen"); if (of_chosen == NULL) of_chosen = of_find_node_by_path("/chosen@0"); + + if (of_chosen) { + const char *name; + + name = of_get_property(of_chosen, "linux,stdout-path", NULL); + if (name) + of_stdout = of_find_node_by_path(name); + } + of_aliases = of_find_node_by_path("/aliases"); if (!of_aliases) return; @@ -1604,7 +1726,7 @@ 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; @@ -1614,7 +1736,7 @@ int of_alias_get_id(struct device_node *np, const char *stem) break; } } - mutex_unlock(&of_aliases_mutex); + mutex_unlock(&of_mutex); return id; } @@ -1660,3 +1782,170 @@ const char *of_prop_next_string(struct property *prop, const char *cur) return curv; } 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. + */ +int of_device_is_stdout_path(struct device_node *dn) +{ + if (!of_stdout) + return false; + + return of_stdout == dn; +} +EXPORT_SYMBOL_GPL(of_device_is_stdout_path); + +/** + * of_graph_parse_endpoint() - parse common endpoint node properties + * @node: pointer to endpoint device_node + * @endpoint: pointer to the OF endpoint data structure + * + * The caller should hold a reference to @node. + */ +int of_graph_parse_endpoint(const struct device_node *node, + struct of_endpoint *endpoint) +{ + struct device_node *port_node = of_get_parent(node); + + WARN_ONCE(!port_node, "%s(): endpoint %s has no parent node\n", + __func__, node->full_name); + + memset(endpoint, 0, sizeof(*endpoint)); + + endpoint->local_node = node; + /* + * It doesn't matter whether the two calls below succeed. + * If they don't then the default value 0 is used. + */ + of_property_read_u32(port_node, "reg", &endpoint->port); + of_property_read_u32(node, "reg", &endpoint->id); + + of_node_put(port_node); + + return 0; +} +EXPORT_SYMBOL(of_graph_parse_endpoint); + +/** + * of_graph_get_next_endpoint() - get next endpoint node + * @parent: pointer to the parent device node + * @prev: previous endpoint node, or NULL to get first + * + * Return: An 'endpoint' node pointer with refcount incremented. Refcount + * of the passed @prev node is not decremented, the caller have to use + * of_node_put() on it when done. + */ +struct device_node *of_graph_get_next_endpoint(const struct device_node *parent, + struct device_node *prev) +{ + struct device_node *endpoint; + struct device_node *port; + + if (!parent) + return NULL; + + /* + * Start by locating the port node. If no previous endpoint is specified + * search for the first port node, otherwise get the previous endpoint + * parent port node. + */ + if (!prev) { + struct device_node *node; + + node = of_get_child_by_name(parent, "ports"); + if (node) + parent = node; + + port = of_get_child_by_name(parent, "port"); + of_node_put(node); + + if (!port) { + pr_err("%s(): no port node found in %s\n", + __func__, parent->full_name); + return NULL; + } + } else { + port = of_get_parent(prev); + if (WARN_ONCE(!port, "%s(): endpoint %s has no parent node\n", + __func__, prev->full_name)) + return NULL; + + /* + * Avoid dropping prev node refcount to 0 when getting the next + * child below. + */ + of_node_get(prev); + } + + while (1) { + /* + * Now that we have a port node, get the next endpoint by + * getting the next child. If the previous endpoint is NULL this + * will return the first child. + */ + endpoint = of_get_next_child(port, prev); + if (endpoint) { + of_node_put(port); + return endpoint; + } + + /* No more endpoints under this port, try the next one. */ + prev = NULL; + + do { + port = of_get_next_child(parent, port); + if (!port) + return NULL; + } while (of_node_cmp(port->name, "port")); + } +} +EXPORT_SYMBOL(of_graph_get_next_endpoint); + +/** + * of_graph_get_remote_port_parent() - get remote port's parent node + * @node: pointer to a local endpoint device_node + * + * Return: Remote device node associated with remote endpoint node linked + * to @node. Use of_node_put() on it when done. + */ +struct device_node *of_graph_get_remote_port_parent( + const struct device_node *node) +{ + struct device_node *np; + unsigned int depth; + + /* Get remote endpoint node. */ + np = of_parse_phandle(node, "remote-endpoint", 0); + + /* Walk 3 levels up only if there is 'ports' node. */ + for (depth = 3; depth && np; depth--) { + np = of_get_next_parent(np); + if (depth == 2 && of_node_cmp(np->name, "ports")) + break; + } + return np; +} +EXPORT_SYMBOL(of_graph_get_remote_port_parent); + +/** + * of_graph_get_remote_port() - get remote port node + * @node: pointer to a local endpoint device_node + * + * Return: Remote port node associated with remote endpoint node linked + * to @node. Use of_node_put() on it when done. + */ +struct device_node *of_graph_get_remote_port(const struct device_node *node) +{ + struct device_node *np; + + /* Get remote endpoint node. */ + np = of_parse_phandle(node, "remote-endpoint", 0); + if (!np) + return NULL; + return of_get_next_parent(np); +} +EXPORT_SYMBOL(of_graph_get_remote_port); |