diff options
| author | Michael Walle <michael@walle.cc> | 2023-02-06 13:43:43 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-02-06 19:06:58 +0100 |
| commit | c5d264d4b527c96ae8903376a4b195df47b05203 (patch) | |
| tree | 583169312beaf4d2b4ef7d50dfb6857f86ecb523 /include/linux/of.h | |
| parent | 7390609b0121a1b982c5ecdfcd72dc328e5784ee (diff) | |
of: base: add of_parse_phandle_with_optional_args()
Add a new variant of the of_parse_phandle_with_args() which treats the
cells name as optional. If it's missing, it is assumed that the phandle
has no arguments.
Up until now, a nvmem node didn't have any arguments, so all the device
trees haven't any '#*-cells' property. But there is a need for an
additional argument for the phandle, for which we need a '#*-cells'
property. Therefore, we need to support nvmem nodes with and without
this property.
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20230206134356.839737-10-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/of.h')
| -rw-r--r-- | include/linux/of.h | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/include/linux/of.h b/include/linux/of.h index 8b9f94386dc3..98c252d2d851 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -1009,6 +1009,31 @@ static inline int of_parse_phandle_with_fixed_args(const struct device_node *np, } /** + * of_parse_phandle_with_optional_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 + * @cells_name: property name that specifies phandles' arguments count + * @index: index of a phandle to parse out + * @out_args: optional pointer to output arguments structure (will be filled) + * + * Same as of_parse_phandle_with_args() except that if the cells_name property + * is not found, cell_count of 0 is assumed. + * + * This is used to useful, if you have a phandle which didn't have arguments + * before and thus doesn't have a '#*-cells' property but is now migrated to + * having arguments while retaining backwards compatibility. + */ +static inline int of_parse_phandle_with_optional_args(const struct device_node *np, + const char *list_name, + const char *cells_name, + int index, + struct of_phandle_args *out_args) +{ + return __of_parse_phandle_with_args(np, list_name, cells_name, + 0, index, out_args); +} + +/** * of_property_count_u8_elems - Count the number of u8 elements in a property * * @np: device node from which the property value is to be read. |