diff options
| author | Grant Likely <grant.likely@secretlab.ca> | 2009-04-25 12:52:40 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-04-27 02:53:45 -0700 |
| commit | 739649c53d7f78f5bf41bdfd1a858ee90c7a687a (patch) | |
| tree | 0e11496435be0cab44c7eaab37964a7c74bd3187 | |
| parent | edf391ff17232f097d72441c9ad467bcb3b5db18 (diff) | |
of: add of_parse_phandle() helper for parsing phandle properties
of_parse_phandle() is a helper function to read and parse a phandle
property and return a pointer to the resulting device_node.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/of/base.c | 24 | ||||
| -rw-r--r-- | include/linux/of.h | 3 |
2 files changed, 27 insertions, 0 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c index 41c5dfd85358..ddf224d456b2 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -495,6 +495,30 @@ int of_modalias_node(struct device_node *node, char *modalias, int len) EXPORT_SYMBOL_GPL(of_modalias_node); /** + * of_parse_phandle - Resolve a phandle property to a device_node pointer + * @np: Pointer to device node holding phandle property + * @phandle_name: Name of property holding a phandle value + * @index: For properties holding a table of phandles, this is the index into + * the table + * + * Returns the device_node pointer with refcount incremented. Use + * of_node_put() on it when done. + */ +struct device_node * +of_parse_phandle(struct device_node *np, const char *phandle_name, int index) +{ + const phandle *phandle; + int size; + + phandle = of_get_property(np, phandle_name, &size); + if ((!phandle) || (size < sizeof(*phandle) * (index + 1))) + return NULL; + + return of_find_node_by_phandle(phandle[index]); +} +EXPORT_SYMBOL(of_parse_phandle); + +/** * of_parse_phandles_with_args - Find a node pointed by phandle in a list * @np: pointer to a device tree node containing a list * @list_name: property name that contains a list diff --git a/include/linux/of.h b/include/linux/of.h index 6a7efa242f5e..7be2d1043c16 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -77,6 +77,9 @@ extern int of_n_size_cells(struct device_node *np); extern const struct of_device_id *of_match_node( const struct of_device_id *matches, const struct device_node *node); extern int of_modalias_node(struct device_node *node, char *modalias, int len); +extern struct device_node *of_parse_phandle(struct device_node *np, + const char *phandle_name, + int index); extern int of_parse_phandles_with_args(struct device_node *np, const char *list_name, const char *cells_name, int index, struct device_node **out_node, const void **out_args); |