Commit 4fcd15a0 authored by Benoit Cousson's avatar Benoit Cousson Committed by Kevin Hilman

of: Add helpers to get one string in multiple strings property

Add of_property_read_string_index and of_property_count_strings
to retrieve one string inside a property that will contains
severals strings.
Signed-off-by: default avatarBenoit Cousson <b-cousson@ti.com>
Acked-by: default avatarGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: default avatarKevin Hilman <khilman@ti.com>
parent f718e2c0
......@@ -661,6 +661,90 @@ int of_property_read_string(struct device_node *np, const char *propname,
}
EXPORT_SYMBOL_GPL(of_property_read_string);
/**
* 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.
*/
int of_property_read_string_index(struct device_node *np, const char *propname,
int index, const char **output)
{
struct property *prop = of_find_property(np, propname, NULL);
int i = 0;
size_t l = 0, total = 0;
const char *p;
if (!prop)
return -EINVAL;
if (!prop->value)
return -ENODATA;
if (strnlen(prop->value, prop->length) >= prop->length)
return -EILSEQ;
p = prop->value;
for (i = 0; total < prop->length; total += l, p += l) {
l = strlen(p) + 1;
if ((*p != 0) && (i++ == index)) {
*output = p;
return 0;
}
}
return -ENODATA;
}
EXPORT_SYMBOL_GPL(of_property_read_string_index);
/**
* 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.
*/
int of_property_count_strings(struct device_node *np, const char *propname)
{
struct property *prop = of_find_property(np, propname, NULL);
int i = 0;
size_t l = 0, total = 0;
const char *p;
if (!prop)
return -EINVAL;
if (!prop->value)
return -ENODATA;
if (strnlen(prop->value, prop->length) >= prop->length)
return -EILSEQ;
p = prop->value;
for (i = 0; total < prop->length; total += l, p += l) {
l = strlen(p) + 1;
if (*p != 0)
i++;
}
return i;
}
EXPORT_SYMBOL_GPL(of_property_count_strings);
/**
* of_parse_phandle - Resolve a phandle property to a device_node pointer
* @np: Pointer to device node holding phandle property
......
......@@ -203,6 +203,11 @@ extern int of_property_read_u32_array(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_count_strings(struct device_node *np,
const char *propname);
extern int of_device_is_compatible(const struct device_node *device,
const char *);
extern int of_device_is_available(const struct device_node *device);
......@@ -256,6 +261,19 @@ 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 **out_string)
{
return -ENOSYS;
}
static inline int of_property_count_strings(struct device_node *np,
const char *propname)
{
return -ENOSYS;
}
static inline const void *of_get_property(const struct device_node *node,
const char *name,
int *lenp)
......
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