diff options
Diffstat (limited to 'drivers/of/base.c')
| -rw-r--r-- | drivers/of/base.c | 303 |
1 files changed, 207 insertions, 96 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c index 2390ddb22d6..321d3ef0500 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -24,38 +24,21 @@ #include <linux/slab.h> #include <linux/proc_fs.h> -/** - * struct alias_prop - Alias property in 'aliases' node - * @link: List node to link the structure in aliases_lookup list - * @alias: Alias property name - * @np: Pointer to device_node that the alias stands for - * @id: Index value from end of alias name - * @stem: Alias string without the index - * - * The structure represents one alias property of 'aliases' node as - * an entry in aliases_lookup list. - */ -struct alias_prop { - struct list_head link; - const char *alias; - struct device_node *np; - int id; - char stem[0]; -}; +#include "of_private.h" -static LIST_HEAD(aliases_lookup); +LIST_HEAD(aliases_lookup); struct device_node *of_allnodes; EXPORT_SYMBOL(of_allnodes); struct device_node *of_chosen; struct device_node *of_aliases; -static DEFINE_MUTEX(of_aliases_mutex); +DEFINE_MUTEX(of_aliases_mutex); /* use when traversing tree through the allnext, child, sibling, * or parent members of struct device_node. */ -DEFINE_RWLOCK(devtree_lock); +DEFINE_RAW_SPINLOCK(devtree_lock); int of_n_addr_cells(struct device_node *np) { @@ -164,16 +147,14 @@ void of_node_put(struct device_node *node) EXPORT_SYMBOL(of_node_put); #endif /* CONFIG_OF_DYNAMIC */ -struct property *of_find_property(const struct device_node *np, - const char *name, - int *lenp) +static struct property *__of_find_property(const struct device_node *np, + const char *name, int *lenp) { struct property *pp; if (!np) return NULL; - read_lock(&devtree_lock); for (pp = np->properties; pp; pp = pp->next) { if (of_prop_cmp(pp->name, name) == 0) { if (lenp) @@ -181,7 +162,20 @@ struct property *of_find_property(const struct device_node *np, break; } } - read_unlock(&devtree_lock); + + return pp; +} + +struct property *of_find_property(const struct device_node *np, + const char *name, + int *lenp) +{ + struct property *pp; + unsigned long flags; + + raw_spin_lock_irqsave(&devtree_lock, flags); + pp = __of_find_property(np, name, lenp); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return pp; } @@ -199,13 +193,13 @@ struct device_node *of_find_all_nodes(struct device_node *prev) { struct device_node *np; - read_lock(&devtree_lock); + raw_spin_lock(&devtree_lock); np = prev ? prev->allnext : of_allnodes; for (; np != NULL; np = np->allnext) if (of_node_get(np)) break; of_node_put(prev); - read_unlock(&devtree_lock); + raw_spin_unlock(&devtree_lock); return np; } EXPORT_SYMBOL(of_find_all_nodes); @@ -214,8 +208,20 @@ 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) +{ + struct property *pp = __of_find_property(np, name, lenp); + + return pp ? pp->value : NULL; +} + +/* + * Find a property with a given name for a given node + * and return the value. + */ const void *of_get_property(const struct device_node *np, const char *name, - int *lenp) + int *lenp) { struct property *pp = of_find_property(np, name, lenp); @@ -226,13 +232,13 @@ EXPORT_SYMBOL(of_get_property); /** Checks if the given "compat" string matches one of the strings in * the device's "compatible" property */ -int of_device_is_compatible(const struct device_node *device, - const char *compat) +static int __of_device_is_compatible(const struct device_node *device, + const char *compat) { const char* cp; int cplen, l; - cp = of_get_property(device, "compatible", &cplen); + cp = __of_get_property(device, "compatible", &cplen); if (cp == NULL) return 0; while (cplen > 0) { @@ -245,6 +251,21 @@ int of_device_is_compatible(const struct device_node *device, return 0; } + +/** Checks if the given "compat" string matches one of the strings in + * the device's "compatible" property + */ +int of_device_is_compatible(const struct device_node *device, + const char *compat) +{ + unsigned long flags; + int res; + + raw_spin_lock_irqsave(&devtree_lock, flags); + res = __of_device_is_compatible(device, compat); + raw_spin_unlock_irqrestore(&devtree_lock, flags); + return res; +} EXPORT_SYMBOL(of_device_is_compatible); /** @@ -269,19 +290,19 @@ int of_machine_is_compatible(const char *compat) EXPORT_SYMBOL(of_machine_is_compatible); /** - * of_device_is_available - check if a device is available for use + * __of_device_is_available - check if a device is available for use * - * @device: Node to check for availability + * @device: Node to check for availability, with locks already held * * Returns 1 if the status property is absent or set to "okay" or "ok", * 0 otherwise */ -int of_device_is_available(const struct device_node *device) +static int __of_device_is_available(const struct device_node *device) { const char *status; int statlen; - status = of_get_property(device, "status", &statlen); + status = __of_get_property(device, "status", &statlen); if (status == NULL) return 1; @@ -292,6 +313,26 @@ int of_device_is_available(const struct device_node *device) return 0; } + +/** + * of_device_is_available - check if a device is available for use + * + * @device: Node to check for availability + * + * Returns 1 if the status property is absent or set to "okay" or "ok", + * 0 otherwise + */ +int of_device_is_available(const struct device_node *device) +{ + unsigned long flags; + int res; + + raw_spin_lock_irqsave(&devtree_lock, flags); + res = __of_device_is_available(device); + raw_spin_unlock_irqrestore(&devtree_lock, flags); + return res; + +} EXPORT_SYMBOL(of_device_is_available); /** @@ -304,13 +345,14 @@ EXPORT_SYMBOL(of_device_is_available); struct device_node *of_get_parent(const struct device_node *node) { struct device_node *np; + unsigned long flags; if (!node) return NULL; - read_lock(&devtree_lock); + raw_spin_lock_irqsave(&devtree_lock, flags); np = of_node_get(node->parent); - read_unlock(&devtree_lock); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return np; } EXPORT_SYMBOL(of_get_parent); @@ -329,14 +371,15 @@ EXPORT_SYMBOL(of_get_parent); struct device_node *of_get_next_parent(struct device_node *node) { struct device_node *parent; + unsigned long flags; if (!node) return NULL; - read_lock(&devtree_lock); + raw_spin_lock_irqsave(&devtree_lock, flags); parent = of_node_get(node->parent); of_node_put(node); - read_unlock(&devtree_lock); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return parent; } @@ -352,14 +395,15 @@ struct device_node *of_get_next_child(const struct device_node *node, struct device_node *prev) { struct device_node *next; + unsigned long flags; - read_lock(&devtree_lock); + raw_spin_lock_irqsave(&devtree_lock, flags); next = prev ? prev->sibling : node->child; for (; next; next = next->sibling) if (of_node_get(next)) break; of_node_put(prev); - read_unlock(&devtree_lock); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return next; } EXPORT_SYMBOL(of_get_next_child); @@ -377,16 +421,16 @@ struct device_node *of_get_next_available_child(const struct device_node *node, { struct device_node *next; - read_lock(&devtree_lock); + raw_spin_lock(&devtree_lock); next = prev ? prev->sibling : node->child; for (; next; next = next->sibling) { - if (!of_device_is_available(next)) + if (!__of_device_is_available(next)) continue; if (of_node_get(next)) break; } of_node_put(prev); - read_unlock(&devtree_lock); + raw_spin_unlock(&devtree_lock); return next; } EXPORT_SYMBOL(of_get_next_available_child); @@ -424,14 +468,15 @@ EXPORT_SYMBOL(of_get_child_by_name); struct device_node *of_find_node_by_path(const char *path) { struct device_node *np = of_allnodes; + unsigned long flags; - read_lock(&devtree_lock); + raw_spin_lock_irqsave(&devtree_lock, flags); for (; np; np = np->allnext) { if (np->full_name && (of_node_cmp(np->full_name, path) == 0) && of_node_get(np)) break; } - read_unlock(&devtree_lock); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return np; } EXPORT_SYMBOL(of_find_node_by_path); @@ -451,15 +496,16 @@ struct device_node *of_find_node_by_name(struct device_node *from, const char *name) { struct device_node *np; + unsigned long flags; - read_lock(&devtree_lock); + raw_spin_lock_irqsave(&devtree_lock, flags); np = from ? from->allnext : of_allnodes; for (; np; np = np->allnext) if (np->name && (of_node_cmp(np->name, name) == 0) && of_node_get(np)) break; of_node_put(from); - read_unlock(&devtree_lock); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return np; } EXPORT_SYMBOL(of_find_node_by_name); @@ -480,15 +526,16 @@ struct device_node *of_find_node_by_type(struct device_node *from, const char *type) { struct device_node *np; + unsigned long flags; - read_lock(&devtree_lock); + raw_spin_lock_irqsave(&devtree_lock, flags); np = from ? from->allnext : of_allnodes; for (; np; np = np->allnext) if (np->type && (of_node_cmp(np->type, type) == 0) && of_node_get(np)) break; of_node_put(from); - read_unlock(&devtree_lock); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return np; } EXPORT_SYMBOL(of_find_node_by_type); @@ -511,18 +558,20 @@ struct device_node *of_find_compatible_node(struct device_node *from, const char *type, const char *compatible) { struct device_node *np; + unsigned long flags; - read_lock(&devtree_lock); + 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) && of_node_get(np)) + if (__of_device_is_compatible(np, compatible) && + of_node_get(np)) break; } of_node_put(from); - read_unlock(&devtree_lock); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return np; } EXPORT_SYMBOL(of_find_compatible_node); @@ -544,8 +593,9 @@ struct device_node *of_find_node_with_property(struct device_node *from, { struct device_node *np; struct property *pp; + unsigned long flags; - read_lock(&devtree_lock); + raw_spin_lock_irqsave(&devtree_lock, flags); np = from ? from->allnext : of_allnodes; for (; np; np = np->allnext) { for (pp = np->properties; pp; pp = pp->next) { @@ -557,20 +607,14 @@ struct device_node *of_find_node_with_property(struct device_node *from, } out: of_node_put(from); - read_unlock(&devtree_lock); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return np; } EXPORT_SYMBOL(of_find_node_with_property); -/** - * of_match_node - Tell if an device_node has a matching of_match structure - * @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. - */ -const struct of_device_id *of_match_node(const struct of_device_id *matches, - const struct device_node *node) +static +const struct of_device_id *__of_match_node(const struct of_device_id *matches, + const struct device_node *node) { if (!matches) return NULL; @@ -584,14 +628,33 @@ const struct of_device_id *of_match_node(const struct of_device_id *matches, match &= node->type && !strcmp(matches->type, node->type); if (matches->compatible[0]) - match &= of_device_is_compatible(node, - matches->compatible); + match &= __of_device_is_compatible(node, + matches->compatible); if (match) return matches; matches++; } return NULL; } + +/** + * of_match_node - Tell if an device_node has a matching of_match structure + * @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. + */ +const struct of_device_id *of_match_node(const struct of_device_id *matches, + const struct device_node *node) +{ + const struct of_device_id *match; + unsigned long flags; + + raw_spin_lock_irqsave(&devtree_lock, flags); + match = __of_match_node(matches, node); + raw_spin_unlock_irqrestore(&devtree_lock, flags); + return match; +} EXPORT_SYMBOL(of_match_node); /** @@ -612,21 +675,24 @@ struct device_node *of_find_matching_node_and_match(struct device_node *from, const struct of_device_id **match) { struct device_node *np; + const struct of_device_id *m; + unsigned long flags; if (match) *match = NULL; - read_lock(&devtree_lock); + raw_spin_lock_irqsave(&devtree_lock, flags); np = from ? from->allnext : of_allnodes; for (; np; np = np->allnext) { - if (of_match_node(matches, np) && of_node_get(np)) { + m = __of_match_node(matches, np); + if (m && of_node_get(np)) { if (match) - *match = matches; + *match = m; break; } } of_node_put(from); - read_unlock(&devtree_lock); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return np; } EXPORT_SYMBOL(of_find_matching_node_and_match); @@ -669,12 +735,12 @@ struct device_node *of_find_node_by_phandle(phandle handle) { struct device_node *np; - read_lock(&devtree_lock); + raw_spin_lock(&devtree_lock); for (np = of_allnodes; np; np = np->allnext) if (np->phandle == handle) break; of_node_get(np); - read_unlock(&devtree_lock); + raw_spin_unlock(&devtree_lock); return np; } EXPORT_SYMBOL(of_find_node_by_phandle); @@ -1025,12 +1091,13 @@ EXPORT_SYMBOL(of_parse_phandle); * 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) +static 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) { const __be32 *list, *list_end; - int size, cur_index = 0; + int rc = 0, size, cur_index = 0; uint32_t count = 0; struct device_node *node = NULL; phandle phandle; @@ -1043,6 +1110,7 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na /* Loop over the phandles until all the requested entry is found */ while (list < list_end) { + rc = -EINVAL; count = 0; /* @@ -1059,13 +1127,13 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na if (!node) { pr_err("%s: could not find phandle\n", np->full_name); - break; + 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); - break; + goto err; } /* @@ -1075,7 +1143,7 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na if (list + count > list_end) { pr_err("%s: arguments longer than property\n", np->full_name); - break; + goto err; } } @@ -1085,9 +1153,10 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na * index matches, then fill the out_args structure and return, * or return -ENOENT for an empty entry. */ + rc = -ENOENT; if (cur_index == index) { if (!phandle) - return -ENOENT; + goto err; if (out_args) { int i; @@ -1098,6 +1167,10 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na for (i = 0; i < count; i++) out_args->args[i] = be32_to_cpup(list++); } + + /* Found it! return success */ + if (node) + of_node_put(node); return 0; } @@ -1107,13 +1180,51 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na cur_index++; } - /* Loop exited without finding a valid entry; return an error */ + /* + * Unlock node before returning result; will be one of: + * -ENOENT : index is for empty phandle + * -EINVAL : parsing error on data + * [1..n] : Number of phandle (count mode; when index = -1) + */ + rc = index < 0 ? cur_index : -ENOENT; + err: if (node) of_node_put(node); - return -EINVAL; + return rc; +} + +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); } EXPORT_SYMBOL(of_parse_phandle_with_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 + * @cells_name: property name that specifies phandles' arguments count + * + * Returns the number of phandle + argument tuples within a property. It + * is a typical pattern to encode a list of phandle and variable + * arguments into a single property. The number of arguments is encoded + * by a property in the phandle-target node. For example, a gpios + * property would contain a list of GPIO specifies consisting of a + * phandle and 1 or more arguments. The number of arguments are + * determined by the #gpio-cells property in the node pointed to by the + * phandle. + */ +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); +} +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) @@ -1146,18 +1257,18 @@ int of_add_property(struct device_node *np, struct property *prop) return rc; prop->next = NULL; - write_lock_irqsave(&devtree_lock, flags); + raw_spin_lock_irqsave(&devtree_lock, flags); next = &np->properties; while (*next) { if (strcmp(prop->name, (*next)->name) == 0) { /* duplicate ! don't insert it */ - write_unlock_irqrestore(&devtree_lock, flags); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return -1; } next = &(*next)->next; } *next = prop; - write_unlock_irqrestore(&devtree_lock, flags); + raw_spin_unlock_irqrestore(&devtree_lock, flags); #ifdef CONFIG_PROC_DEVICETREE /* try to add to proc as well if it was initialized */ @@ -1187,7 +1298,7 @@ int of_remove_property(struct device_node *np, struct property *prop) if (rc) return rc; - write_lock_irqsave(&devtree_lock, flags); + raw_spin_lock_irqsave(&devtree_lock, flags); next = &np->properties; while (*next) { if (*next == prop) { @@ -1200,7 +1311,7 @@ int of_remove_property(struct device_node *np, struct property *prop) } next = &(*next)->next; } - write_unlock_irqrestore(&devtree_lock, flags); + raw_spin_unlock_irqrestore(&devtree_lock, flags); if (!found) return -ENODEV; @@ -1240,7 +1351,7 @@ int of_update_property(struct device_node *np, struct property *newprop) if (!oldprop) return of_add_property(np, newprop); - write_lock_irqsave(&devtree_lock, flags); + raw_spin_lock_irqsave(&devtree_lock, flags); next = &np->properties; while (*next) { if (*next == oldprop) { @@ -1254,7 +1365,7 @@ int of_update_property(struct device_node *np, struct property *newprop) } next = &(*next)->next; } - write_unlock_irqrestore(&devtree_lock, flags); + raw_spin_unlock_irqrestore(&devtree_lock, flags); if (!found) return -ENODEV; @@ -1327,12 +1438,12 @@ int of_attach_node(struct device_node *np) if (rc) return rc; - write_lock_irqsave(&devtree_lock, flags); + raw_spin_lock_irqsave(&devtree_lock, flags); np->sibling = np->parent->child; np->allnext = of_allnodes; np->parent->child = np; of_allnodes = np; - write_unlock_irqrestore(&devtree_lock, flags); + raw_spin_unlock_irqrestore(&devtree_lock, flags); of_add_proc_dt_entry(np); return 0; @@ -1375,17 +1486,17 @@ int of_detach_node(struct device_node *np) if (rc) return rc; - write_lock_irqsave(&devtree_lock, flags); + raw_spin_lock_irqsave(&devtree_lock, flags); if (of_node_check_flag(np, OF_DETACHED)) { /* someone already detached it */ - write_unlock_irqrestore(&devtree_lock, flags); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return rc; } parent = np->parent; if (!parent) { - write_unlock_irqrestore(&devtree_lock, flags); + raw_spin_unlock_irqrestore(&devtree_lock, flags); return rc; } @@ -1412,7 +1523,7 @@ int of_detach_node(struct device_node *np) } of_node_set_flag(np, OF_DETACHED); - write_unlock_irqrestore(&devtree_lock, flags); + raw_spin_unlock_irqrestore(&devtree_lock, flags); of_remove_proc_dt_entry(np); return rc; |