From 6441dfa8307a564f797b868a74205fe9c2f42eb0 Mon Sep 17 00:00:00 2001 From: Sascha Hauer Date: Fri, 22 Nov 2019 09:38:29 +0100 Subject: of: Add of_property_read_string_array() of_property_read_string_array() is used to read a multistring device tree property into an array of strings. This is taken from the kernel. It is implemented around of_property_read_string_helper() which can be used to implement of_property_count_strings() and of_property_read_string_index() as well. Signed-off-by: Sascha Hauer --- include/of.h | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 70 insertions(+), 13 deletions(-) (limited to 'include') diff --git a/include/of.h b/include/of.h index 98ddf795cb..f63a3efe13 100644 --- a/include/of.h +++ b/include/of.h @@ -197,14 +197,12 @@ extern int of_property_read_u64(const struct device_node *np, extern int of_property_read_string(struct device_node *np, const char *propname, const char **out_string); -extern int of_property_read_string_index(struct device_node *np, - const char *propname, - int index, const char **output); extern int of_property_match_string(struct device_node *np, const char *propname, const char *string); -extern int of_property_count_strings(struct device_node *np, - const char *propname); +extern int of_property_read_string_helper(const struct device_node *np, + const char *propname, + const char **out_strs, size_t sz, int index); extern const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur, u32 *pu); @@ -444,20 +442,15 @@ static inline int of_property_read_string(struct device_node *np, return -ENOSYS; } -static inline int of_property_read_string_index(struct device_node *np, - const char *propname, int index, const char **output) -{ - return -ENOSYS; -} - static inline int of_property_match_string(struct device_node *np, const char *propname, const char *string) { return -ENOSYS; } -static inline int of_property_count_strings(struct device_node *np, - const char *propname) +static inline int of_property_read_string_helper(const struct device_node *np, + const char *propname, + const char **out_strs, size_t sz, int index) { return -ENOSYS; } @@ -752,6 +745,70 @@ static inline struct device_node *of_find_matching_node( for (child = of_get_next_available_child(parent, NULL); child != NULL; \ child = of_get_next_available_child(parent, child)) +/** + * of_property_read_string_array() - Read an array of strings from a multiple + * strings property. + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @out_strs: output array of string pointers. + * @sz: number of array elements to read. + * + * Search for a property in a device tree node and retrieve a list of + * terminated string values (pointer to data, not a copy) in that property. + * + * If @out_strs is NULL, the number of strings in the property is returned. + */ +static inline int of_property_read_string_array(const struct device_node *np, + const char *propname, const char **out_strs, + size_t sz) +{ + return of_property_read_string_helper(np, propname, out_strs, sz, 0); +} + +/** + * of_property_count_strings() - Find and return the number of strings from a + * multiple strings property. + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * + * Search for a property in a device tree node and retrieve the number of null + * terminated string contain in it. Returns the number of strings on + * success, -EINVAL if the property does not exist, -ENODATA if property + * does not have a value, and -EILSEQ if the string is not null-terminated + * within the length of the property data. + */ +static inline int of_property_count_strings(const struct device_node *np, + const char *propname) +{ + return of_property_read_string_helper(np, propname, NULL, 0, 0); +} + +/** + * of_property_read_string_index() - Find and read a string from a multiple + * strings property. + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @index: index of the string in the list of strings + * @out_string: pointer to null terminated return string, modified only if + * return value is 0. + * + * Search for a property in a device tree node and retrieve a null + * terminated string value (pointer to data, not a copy) in the list of strings + * contained in that property. + * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if + * property does not have a value, and -EILSEQ if the string is not + * null-terminated within the length of the property data. + * + * The out_string pointer is modified only if a valid string can be decoded. + */ +static inline int of_property_read_string_index(const struct device_node *np, + const char *propname, + int index, const char **output) +{ + int rc = of_property_read_string_helper(np, propname, output, 1, index); + return rc < 0 ? rc : 0; +} + /** * of_property_read_bool - Findfrom a property * @np: device node from which the property value is to be read. -- cgit v1.2.3