Commit 7aff0fe3 authored by Grant Likely's avatar Grant Likely

of: Add of_property_match_string() to find index into a string list

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: default avatarGrant Likely <grant.likely@secretlab.ca>
parent dcd6c922
......@@ -31,6 +31,8 @@ consumer-a {
phandle-list-bad-phandle = <12345678 0 0>;
phandle-list-bad-args = <&provider2 1 0>,
<&provider3 0>;
empty-property;
unterminated-string = [40 41 42 43];
};
};
};
......
......@@ -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
......
......@@ -120,6 +120,34 @@ static void __init of_selftest_parse_phandle_with_args(void)
pr_info("end - %s\n", passed_all ? "PASS" : "FAIL");
}
static void __init of_selftest_property_match_string(void)
{
struct device_node *np;
int rc;
pr_info("start\n");
np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
if (!np) {
pr_err("No testcase data in device tree\n");
return;
}
rc = of_property_match_string(np, "phandle-list-names", "first");
selftest(rc == 0, "first expected:0 got:%i\n", rc);
rc = of_property_match_string(np, "phandle-list-names", "second");
selftest(rc == 1, "second expected:0 got:%i\n", rc);
rc = of_property_match_string(np, "phandle-list-names", "third");
selftest(rc == 2, "third expected:0 got:%i\n", rc);
rc = of_property_match_string(np, "phandle-list-names", "fourth");
selftest(rc == -ENODATA, "unmatched string; rc=%i", rc);
rc = of_property_match_string(np, "missing-property", "blah");
selftest(rc == -EINVAL, "missing property; rc=%i", rc);
rc = of_property_match_string(np, "empty-property", "blah");
selftest(rc == -ENODATA, "empty property; rc=%i", rc);
rc = of_property_match_string(np, "unterminated-string", "blah");
selftest(rc == -EILSEQ, "unterminated string; rc=%i", rc);
}
static int __init of_selftest(void)
{
struct device_node *np;
......@@ -133,6 +161,7 @@ static int __init of_selftest(void)
pr_info("start of selftest - you will see error messages\n");
of_selftest_parse_phandle_with_args();
of_selftest_property_match_string();
pr_info("end of selftest - %s\n", selftest_passed ? "PASS" : "FAIL");
return 0;
}
......
......@@ -217,6 +217,9 @@ 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,
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment