From 035fd9482274bf43858b00e0ff95179af66df8e8 Mon Sep 17 00:00:00 2001 From: Stephen Warren Date: Wed, 14 Aug 2013 15:27:10 -0600 Subject: [PATCH] of: introduce of_parse_phandle_with_fixed_args This is identical to of_parse_phandle_with_args(), except that the number of argument cells is fixed, rather than being parsed out of the node referenced by each phandle. Signed-off-by: Stephen Warren Acked-by: Mark Rutland Signed-off-by: Grant Likely --- drivers/of/base.c | 66 ++++++++++++++++++++++++++++++++++++++++------ include/linux/of.h | 10 +++++++ 2 files changed, 68 insertions(+), 8 deletions(-) diff --git a/drivers/of/base.c b/drivers/of/base.c index ef2f1d0dd80a..1f80acf4c16a 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -1082,7 +1082,8 @@ EXPORT_SYMBOL_GPL(of_property_count_strings); 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; @@ -1118,11 +1119,17 @@ static int __of_parse_phandle_with_args(const struct device_node *np, 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; } /* @@ -1244,10 +1251,52 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na { 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 @@ -1266,7 +1315,8 @@ 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); diff --git a/include/linux/of.h b/include/linux/of.h index 90a8811e9e48..87d08306fef4 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -280,6 +280,9 @@ extern struct device_node *of_parse_phandle(const struct device_node *np, extern 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); +extern int of_parse_phandle_with_fixed_args(const struct device_node *np, + const char *list_name, int cells_count, int index, + struct of_phandle_args *out_args); extern int of_count_phandle_with_args(const struct device_node *np, const char *list_name, const char *cells_name); @@ -477,6 +480,13 @@ static inline int of_parse_phandle_with_args(struct device_node *np, return -ENOSYS; } +static inline int of_parse_phandle_with_fixed_args(const struct device_node *np, + const char *list_name, int cells_count, int index, + struct of_phandle_args *out_args) +{ + return -ENOSYS; +} + static inline int of_count_phandle_with_args(struct device_node *np, const char *list_name, const char *cells_name) -- 2.30.2