From patchwork Wed Jun 6 12:27:53 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [08/21] of: Add of_property_match_string() to find index into a string list Date: Wed, 06 Jun 2012 02:27:53 -0000 From: Ike Panhc X-Patchwork-Id: 163342 Message-Id: <1338985673-26207-1-git-send-email-ike.pan@canonical.com> To: kernel-team@lists.ubuntu.com From: Grant Likely BugLink: http://launchpad.net/bugs/1008345 Add a helper function for finding the index of a string in a string list property. This helper is useful for bindings that use a separate *-name property for attaching names to tuples in another property such as 'reg' or 'gpios'. Signed-off-by: Grant Likely (backported from commit 7aff0fe33033fc75b61446ba29d38b1b1354af9f) Signed-off-by: Ike Panhc --- drivers/of/base.c | 36 ++++++++++++++++++++++++++++++++++++ include/linux/of.h | 3 +++ 2 files changed, 39 insertions(+) diff --git a/drivers/of/base.c b/drivers/of/base.c index c6db9ab..ff3c1fb 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -761,6 +761,42 @@ int of_property_read_string_index(struct device_node *np, const char *propname, } EXPORT_SYMBOL_GPL(of_property_read_string_index); +/** + * of_property_match_string() - Find string in a list and return index + * @np: pointer to node containing string list property + * @propname: string list property name + * @string: pointer to string to search for in string list + * + * This function searches a string list property and returns the index + * of a specific string value. + */ +int of_property_match_string(struct device_node *np, const char *propname, + const char *string) +{ + struct property *prop = of_find_property(np, propname, NULL); + size_t l; + int i; + const char *p, *end; + + if (!prop) + return -EINVAL; + if (!prop->value) + return -ENODATA; + + p = prop->value; + end = p + prop->length; + + for (i = 0; p < end; i++, p += l) { + l = strlen(p) + 1; + if (p + l > end) + return -EILSEQ; + pr_debug("comparing %s with %s\n", string, p); + if (strcmp(string, p) == 0) + return i; /* Found it; return index */ + } + return -ENODATA; +} +EXPORT_SYMBOL_GPL(of_property_match_string); /** * of_property_count_strings - Find and return the number of strings from a diff --git a/include/linux/of.h b/include/linux/of.h index ea44fd7..f02794e 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -218,6 +218,9 @@ extern int of_property_read_string(struct device_node *np, 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_device_is_compatible(const struct device_node *device,