leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

device property: Add fwnode_property_match_string()

Browse Source 
Sometimes it is useful to be able to extract an index of certain string
value from an array of strings. A typical use case is to give a name to a
DMA channel, PWM, clock and so on.

Provide an implementation using unified device property accessors that
follows of_property_match_string() but works for all supported fwnodes.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Mika Westerberg 2015-09-14 17:37:35 +03:00 committed by Rafael J. Wysocki
parent 504a337499
commit 3f5c8d3187
2 changed files with 72 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

68
drivers/base/property.c
View File

@ -287,6 +287,28 @@ int device_property_read_string(struct device *dev, const char *propname,
}
EXPORT_SYMBOL_GPL(device_property_read_string);
/**
* device_property_match_string - find a string in an array and return index
* @dev: Device to get the property of
* @propname: Name of the property holding the array
* @string: String to look for
*
* Find a given string in a string array and if it is found return the
* index back.
*
* Return: %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of strings,
* %-ENXIO if no suitable firmware interface is present.
*/
int device_property_match_string(struct device *dev, const char *propname,
const char *string)
{
return fwnode_property_match_string(dev_fwnode(dev), propname, string);
}
EXPORT_SYMBOL_GPL(device_property_match_string);
#define OF_DEV_PROP_READ_ARRAY(node, propname, type, val, nval) \
(val) ? of_property_read_##type##_array((node), (propname), (val), (nval)) \
: of_property_count_elems_of_size((node), (propname), sizeof(type))
@ -478,6 +500,52 @@ int fwnode_property_read_string(struct fwnode_handle *fwnode,
}
EXPORT_SYMBOL_GPL(fwnode_property_read_string);
/**
* fwnode_property_match_string - find a string in an array and return index
* @fwnode: Firmware node to get the property of
* @propname: Name of the property holding the array
* @string: String to look for
*
* Find a given string in a string array and if it is found return the
* index back.
*
* Return: %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of strings,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_match_string(struct fwnode_handle *fwnode,
const char *propname, const char *string)
{
const char **values;
int nval, ret, i;
nval = fwnode_property_read_string_array(fwnode, propname, NULL, 0);
if (nval < 0)
return nval;
values = kcalloc(nval, sizeof(*values), GFP_KERNEL);
if (!values)
return -ENOMEM;
ret = fwnode_property_read_string_array(fwnode, propname, values, nval);
if (ret < 0)
goto out;
ret = -ENODATA;
for (i = 0; i < nval; i++) {
if (!strcmp(values[i], string)) {
ret = i;
break;
}
}
out:
kfree(values);
return ret;
}
EXPORT_SYMBOL_GPL(fwnode_property_match_string);
/**
* device_get_next_child_node - Return the next child node handle for a device
* @dev: Device to find the next child node for.

4
include/linux/property.h
View File

@ -40,6 +40,8 @@ int device_property_read_string_array(struct device *dev, const char *propname,
const char **val, size_t nval);
int device_property_read_string(struct device *dev, const char *propname,
const char **val);
int device_property_match_string(struct device *dev,
const char *propname, const char *string);
bool fwnode_property_present(struct fwnode_handle *fwnode, const char *propname);
int fwnode_property_read_u8_array(struct fwnode_handle *fwnode,
@ -59,6 +61,8 @@ int fwnode_property_read_string_array(struct fwnode_handle *fwnode,
size_t nval);
int fwnode_property_read_string(struct fwnode_handle *fwnode,
const char *propname, const char **val);
int fwnode_property_match_string(struct fwnode_handle *fwnode,
const char *propname, const char *string);
struct fwnode_handle *device_get_next_child_node(struct device *dev,
struct fwnode_handle *child);