diff options
Diffstat (limited to 'drivers/of/base.c')
-rw-r--r-- | drivers/of/base.c | 607 |
1 files changed, 462 insertions, 145 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c index 10b51106c854..4557a142c752 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -21,8 +21,10 @@ #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" @@ -35,6 +37,12 @@ struct device_node *of_chosen; struct device_node *of_aliases; static struct device_node *of_stdout; +static struct kset *of_kset; + +/* + * Used to protect the of_aliases; but also overloaded to hold off addition of + * nodes to sysfs + */ DEFINE_MUTEX(of_aliases_mutex); /* use when traversing tree through the allnext, child, sibling, @@ -92,14 +100,14 @@ int __weak of_node_to_nid(struct device_node *np) struct device_node *of_node_get(struct device_node *node) { if (node) - kref_get(&node->kref); + kobject_get(&node->kobj); return node; } EXPORT_SYMBOL(of_node_get); -static inline struct device_node *kref_to_device_node(struct kref *kref) +static inline struct device_node *kobj_to_device_node(struct kobject *kobj) { - return container_of(kref, struct device_node, kref); + return container_of(kobj, struct device_node, kobj); } /** @@ -109,16 +117,15 @@ static inline struct device_node *kref_to_device_node(struct kref *kref) * In of_node_put() this function is passed to kref_put() * as the destructor. */ -static void of_node_release(struct kref *kref) +static void of_node_release(struct kobject *kobj) { - struct device_node *node = kref_to_device_node(kref); + 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(); - kref_init(&node->kref); return; } @@ -151,11 +158,154 @@ static void of_node_release(struct kref *kref) void of_node_put(struct device_node *node) { if (node) - kref_put(&node->kref, of_node_release); + kobject_put(&node->kobj); } EXPORT_SYMBOL(of_node_put); +#else +static void of_node_release(struct kobject *kobj) +{ + /* Without CONFIG_OF_DYNAMIC, no nodes gets freed */ +} #endif /* CONFIG_OF_DYNAMIC */ +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) +{ + struct property *pp = container_of(bin_attr, struct property, attr); + return memory_read_from_buffer(buf, count, &offset, pp->value, pp->length); +} + +static const char *safe_name(struct kobject *kobj, const char *orig_name) +{ + const char *name = orig_name; + struct kernfs_node *kn; + int i = 0; + + /* don't be a hero. After 16 tries give up */ + while (i < 16 && (kn = sysfs_get_dirent(kobj->sd, name))) { + sysfs_put(kn); + if (name != orig_name) + kfree(name); + name = kasprintf(GFP_KERNEL, "%s#%i", orig_name, ++i); + } + + if (name != orig_name) + pr_warn("device-tree: Duplicate name in %s, renamed to \"%s\"\n", + kobject_name(kobj), name); + return name; +} + +static 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; + + 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; +} + +static int __of_node_add(struct device_node *np) +{ + const char *name; + struct property *pp; + int rc; + + 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); + } + if (rc) + return rc; + + for_each_property_of_node(np, pp) + __of_add_property_sysfs(np, pp); + + 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); + of_kset = kset_create_and_add("devicetree", NULL, firmware_kobj); + if (!of_kset) { + mutex_unlock(&of_aliases_mutex); + return -ENOMEM; + } + for_each_of_allnodes(np) + __of_node_add(np); + mutex_unlock(&of_aliases_mutex); + + /* Symlink in /proc as required by userspace ABI */ + if (of_allnodes) + proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base"); + + return 0; +} +core_initcall(of_init); + static struct property *__of_find_property(const struct device_node *np, const char *name, int *lenp) { @@ -342,27 +492,72 @@ struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) } EXPORT_SYMBOL(of_get_cpu_node); -/** Checks if the given "compat" string matches one of the strings in - * the device's "compatible" property +/** + * __of_device_is_compatible() - Check if the node matches given constraints + * @device: pointer to node + * @compat: required compatible string, NULL or "" for any match + * @type: required device_type value, NULL or "" for any match + * @name: required node name, NULL or "" for any match + * + * Checks if the given @compat, @type and @name strings match the + * properties of the given @device. A constraints can be skipped by + * passing NULL or an empty string as the constraint. + * + * Returns 0 for no match, and a positive integer on match. The return + * value is a relative score with larger values indicating better + * matches. The score is weighted for the most specific compatible value + * to get the highest score. Matching type is next, followed by matching + * name. Practically speaking, this results in the following priority + * order for matches: + * + * 1. specific compatible && type && name + * 2. specific compatible && type + * 3. specific compatible && name + * 4. specific compatible + * 5. general compatible && type && name + * 6. general compatible && type + * 7. general compatible && name + * 8. general compatible + * 9. type && name + * 10. type + * 11. name */ static int __of_device_is_compatible(const struct device_node *device, - const char *compat) + const char *compat, const char *type, const char *name) { - const char* cp; - int cplen, l; + struct property *prop; + const char *cp; + int index = 0, score = 0; + + /* Compatible match has highest priority */ + if (compat && compat[0]) { + prop = __of_find_property(device, "compatible", NULL); + for (cp = of_prop_next_string(prop, NULL); cp; + cp = of_prop_next_string(prop, cp), index++) { + if (of_compat_cmp(cp, compat, strlen(compat)) == 0) { + score = INT_MAX/2 - (index << 2); + break; + } + } + if (!score) + return 0; + } - cp = __of_get_property(device, "compatible", &cplen); - if (cp == NULL) - return 0; - while (cplen > 0) { - if (of_compat_cmp(cp, compat, strlen(compat)) == 0) - return 1; - l = strlen(cp) + 1; - cp += l; - cplen -= l; + /* Matching type is better than matching name */ + if (type && type[0]) { + if (!device->type || of_node_cmp(type, device->type)) + return 0; + score += 2; } - return 0; + /* Matching name is a bit better than not */ + if (name && name[0]) { + if (!device->name || of_node_cmp(name, device->name)) + return 0; + score++; + } + + return score; } /** Checks if the given "compat" string matches one of the strings in @@ -375,7 +570,7 @@ int of_device_is_compatible(const struct device_node *device, int res; raw_spin_lock_irqsave(&devtree_lock, flags); - res = __of_device_is_compatible(device, compat); + res = __of_device_is_compatible(device, compat, NULL, NULL); raw_spin_unlock_irqrestore(&devtree_lock, flags); return res; } @@ -681,10 +876,7 @@ struct device_node *of_find_compatible_node(struct device_node *from, raw_spin_lock_irqsave(&devtree_lock, flags); np = from ? from->allnext : of_allnodes; for (; np; np = np->allnext) { - if (type - && !(np->type && (of_node_cmp(np->type, type) == 0))) - continue; - if (__of_device_is_compatible(np, compatible) && + if (__of_device_is_compatible(np, compatible, type, NULL) && of_node_get(np)) break; } @@ -730,65 +922,26 @@ out: } EXPORT_SYMBOL(of_find_node_with_property); -static const struct of_device_id * -of_match_compatible(const struct of_device_id *matches, - const struct device_node *node) -{ - const char *cp; - int cplen, l; - const struct of_device_id *m; - - cp = __of_get_property(node, "compatible", &cplen); - while (cp && (cplen > 0)) { - m = matches; - while (m->name[0] || m->type[0] || m->compatible[0]) { - /* Only match for the entries without type and name */ - if (m->name[0] || m->type[0] || - of_compat_cmp(m->compatible, cp, - strlen(m->compatible))) - m++; - else - return m; - } - - /* Get node's next compatible string */ - l = strlen(cp) + 1; - cp += l; - cplen -= l; - } - - return NULL; -} - static const struct of_device_id *__of_match_node(const struct of_device_id *matches, const struct device_node *node) { - const struct of_device_id *m; + const struct of_device_id *best_match = NULL; + int score, best_score = 0; if (!matches) return NULL; - m = of_match_compatible(matches, node); - if (m) - return m; - - while (matches->name[0] || matches->type[0] || matches->compatible[0]) { - int match = 1; - if (matches->name[0]) - match &= node->name - && !strcmp(matches->name, node->name); - if (matches->type[0]) - match &= node->type - && !strcmp(matches->type, node->type); - if (matches->compatible[0]) - match &= __of_device_is_compatible(node, - matches->compatible); - if (match) - return matches; - matches++; + for (; matches->name[0] || matches->type[0] || matches->compatible[0]; matches++) { + score = __of_device_is_compatible(node, matches->compatible, + matches->type, matches->name); + if (score > best_score) { + best_match = matches; + best_score = score; + } } - return NULL; + + return best_match; } /** @@ -796,12 +949,7 @@ const struct of_device_id *__of_match_node(const struct of_device_id *matches, * @matches: array of of device match structures to search in * @node: the of device structure to match against * - * Low level utility function used by device matching. We have two ways - * of matching: - * - Try to find the best compatible match by comparing each compatible - * string of device node with all the given matches respectively. - * - If the above method failed, then try to match the compatible by using - * __of_device_is_compatible() besides the match in type and name. + * Low level utility function used by device matching. */ const struct of_device_id *of_match_node(const struct of_device_id *matches, const struct device_node *node) @@ -906,6 +1054,38 @@ 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. @@ -1500,6 +1680,10 @@ static int of_property_notify(int action, struct device_node *np, { 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); @@ -1513,11 +1697,31 @@ static int of_property_notify(int action, struct device_node *np, #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) +{ + struct property **next; + + prop->next = NULL; + next = &np->properties; + while (*next) { + if (strcmp(prop->name, (*next)->name) == 0) + /* duplicate ! don't insert it */ + return -EEXIST; + + next = &(*next)->next; + } + *next = prop; + + return 0; +} + +/** * of_add_property - Add a property to a node */ int of_add_property(struct device_node *np, struct property *prop) { - struct property **next; unsigned long flags; int rc; @@ -1525,27 +1729,16 @@ int of_add_property(struct device_node *np, struct property *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) { - /* duplicate ! don't insert it */ - raw_spin_unlock_irqrestore(&devtree_lock, flags); - return -1; - } - next = &(*next)->next; - } - *next = prop; + rc = __of_add_property(np, prop); raw_spin_unlock_irqrestore(&devtree_lock, flags); + if (rc) + return rc; -#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 */ + if (of_node_is_attached(np)) + __of_add_property_sysfs(np, prop); - return 0; + return rc; } /** @@ -1585,11 +1778,11 @@ int of_remove_property(struct device_node *np, struct property *prop) if (!found) return -ENODEV; -#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 */ + /* at early boot, bail hear and defer setup to of_init() */ + if (!of_kset) + return 0; + + sysfs_remove_bin_file(&np->kobj, &prop->attr); return 0; } @@ -1635,16 +1828,17 @@ int of_update_property(struct device_node *np, struct property *newprop) next = &(*next)->next; } raw_spin_unlock_irqrestore(&devtree_lock, flags); + if (rc) + return rc; + + /* Update the sysfs attribute */ + if (oldprop) + sysfs_remove_bin_file(&np->kobj, &oldprop->attr); + __of_add_property_sysfs(np, newprop); if (!found) 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 */ - return 0; } @@ -1679,22 +1873,6 @@ int of_reconfig_notify(unsigned long action, void *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) -{ - return; -} -#endif - /** * of_attach_node - Plug a device node into the tree and global list. */ @@ -1712,24 +1890,13 @@ int of_attach_node(struct device_node *np) np->allnext = of_allnodes; np->parent->child = np; of_allnodes = np; + of_node_clear_flag(np, OF_DETACHED); raw_spin_unlock_irqrestore(&devtree_lock, flags); - of_add_proc_dt_entry(np); + of_node_add(np); return 0; } -#ifdef CONFIG_PROC_DEVICETREE -static void of_remove_proc_dt_entry(struct device_node *dn) -{ - proc_remove(dn->pde); -} -#else -static void of_remove_proc_dt_entry(struct device_node *dn) -{ - return; -} -#endif - /** * of_detach_node - "Unplug" a node from the device tree. * @@ -1785,7 +1952,7 @@ int of_detach_node(struct device_node *np) of_node_set_flag(np, OF_DETACHED); raw_spin_unlock_irqrestore(&devtree_lock, flags); - of_remove_proc_dt_entry(np); + of_node_remove(np); return rc; } #endif /* defined(CONFIG_OF_DYNAMIC) */ @@ -1821,9 +1988,9 @@ void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align)) 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); + const char *name = of_get_property(of_chosen, "stdout-path", NULL); + if (!name) + name = of_get_property(of_chosen, "linux,stdout-path", NULL); if (name) of_stdout = of_find_node_by_path(name); } @@ -1984,3 +2151,153 @@ struct device_node *of_find_next_cache_node(const struct device_node *np) return NULL; } + +/** + * 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 = NULL; + + if (!parent) + return NULL; + + if (!prev) { + struct device_node *node; + /* + * It's the first call, we have to find a port subnode + * within this node or within an optional 'ports' node. + */ + node = of_get_child_by_name(parent, "ports"); + if (node) + parent = node; + + port = of_get_child_by_name(parent, "port"); + + if (port) { + /* Found a port, get an endpoint. */ + endpoint = of_get_next_child(port, NULL); + of_node_put(port); + } else { + endpoint = NULL; + } + + if (!endpoint) + pr_err("%s(): no endpoint nodes specified for %s\n", + __func__, parent->full_name); + of_node_put(node); + + return endpoint; + } + + 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. */ + of_node_get(prev); + 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. */ + do { + port = of_get_next_child(parent, port); + if (!port) + return NULL; + } while (of_node_cmp(port->name, "port")); + + /* Pick up the first endpoint in this port. */ + endpoint = of_get_next_child(port, NULL); + of_node_put(port); + + return endpoint; +} +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); |