dpll: core: add helpers to find DPLL pin fwnode
Add helper functions to the DPLL core to retrieve a DPLL pin's firmware
node handle based on the 'dpll-pins' and 'dpll-pin-names' properties.
Unlike simple phandle arrays, 'dpll-pins' entries typically contain
a pin specifier (index and direction) as defined by '#dpll-pin-cells'.
The new helper fwnode_dpll_pin_node_get() parses these specifiers
using fwnode_property_get_reference_args(). It resolves the target
pin by:
1. Identifying the DPLL device node from the phandle.
2. Selecting the correct sub-node ('input-pins' or 'output-pins') based
on the direction argument.
3. Matching the pin index argument against the 'reg' property of
the child nodes.
Additionally, register 'dpll-pins' in drivers/of/property.c to enable
proper parsing of the supplier bindings by the OF core.
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
v2:
* added check for fwnode_property_match_string() return value
* reworked searching for the pin using dpll device phandle and
pin specifier
* added dpll-pins into OF core supplier_bindings
---
drivers/dpll/dpll_core.c | 74 ++++++++++++++++++++++++++++++++++++++++
drivers/of/property.c | 2 ++
include/linux/dpll.h | 15 ++++++++
3 files changed, 91 insertions(+)
diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c
index fb68b5e19b480..b0083b5c10aa4 100644
--- a/drivers/dpll/dpll_core.c
+++ b/drivers/dpll/dpll_core.c
@@ -13,6 +13,7 @@
#include <linux/property.h>
#include <linux/slab.h>
#include <linux/string.h>
+#include <dt-bindings/dpll/dpll.h>
#include "dpll_core.h"
#include "dpll_netlink.h"
@@ -654,6 +655,79 @@ struct dpll_pin *fwnode_dpll_pin_find(struct fwnode_handle *fwnode)
}
EXPORT_SYMBOL_GPL(fwnode_dpll_pin_find);
+/**
+ * fwnode_dpll_pin_node_get - get dpll pin node from given fw node and pin name
+ * @fwnode: firmware node that uses the dpll pin
+ * @name: dpll pin name from dpll-pin-names property
+ *
+ * Return: ERR_PTR() on error or a valid firmware node handle on success.
+ */
+struct fwnode_handle *fwnode_dpll_pin_node_get(struct fwnode_handle *fwnode,
+ const char *name)
+{
+ struct fwnode_handle *parent_node, *pin_node;
+ struct fwnode_reference_args args;
+ const char *parent_name;
+ int ret, index = 0;
+
+ if (name) {
+ index = fwnode_property_match_string(fwnode, "dpll-pin-names",
+ name);
+ if (index < 0)
+ return ERR_PTR(-ENOENT);
+ }
+
+ ret = fwnode_property_get_reference_args(fwnode, "dpll-pins",
+ "#dpll-pin-cells", 2, index,
+ &args);
+ if (ret)
+ return ERR_PTR(ret);
+
+ /* We support only 2 cell DPLL bindings in the kernel currently. */
+ if (args.nargs != 2) {
+ fwnode_handle_put(args.fwnode);
+ return ERR_PTR(-ENOENT);
+ }
+
+ /* Resolve parent node name according pin direction type */
+ switch (args.args[1]) {
+ case DPLL_PIN_INPUT:
+ parent_name = "input-pins";
+ break;
+ case DPLL_PIN_OUTPUT:
+ parent_name = "output-pins";
+ break;
+ default:
+ fwnode_handle_put(args.fwnode);
+ return ERR_PTR(-EINVAL);
+ }
+
+ /* Get pin's parent sub-node */
+ parent_node = fwnode_get_named_child_node(args.fwnode, parent_name);
+ if (!parent_node) {
+ fwnode_handle_put(args.fwnode);
+ return ERR_PTR(-ENOENT);
+ }
+
+ /* Enumerate child pin nodes and find the requested one */
+ fwnode_for_each_child_node(parent_node, pin_node) {
+ u32 reg;
+
+ if (fwnode_property_read_u32(pin_node, "reg", ®))
+ continue;
+
+ if (reg == args.args[0])
+ break;
+ }
+
+ /* Release pin's parent and dpll device node */
+ fwnode_handle_put(parent_node);
+ fwnode_handle_put(args.fwnode);
+
+ return pin_node ? pin_node : ERR_PTR(-ENOENT);
+}
+EXPORT_SYMBOL_GPL(fwnode_dpll_pin_node_get);
+
static int
__dpll_pin_register(struct dpll_device *dpll, struct dpll_pin *pin,
const struct dpll_pin_ops *ops, void *priv, void *cookie)
diff --git a/drivers/of/property.c b/drivers/of/property.c
index 4e3524227720a..8571c8bb71ade 100644
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -1410,6 +1410,7 @@ DEFINE_SIMPLE_PROP(post_init_providers, "post-init-providers", NULL)
DEFINE_SIMPLE_PROP(access_controllers, "access-controllers", "#access-controller-cells")
DEFINE_SIMPLE_PROP(pses, "pses", "#pse-cells")
DEFINE_SIMPLE_PROP(power_supplies, "power-supplies", NULL)
+DEFINE_SIMPLE_PROP(dpll_pins, "dpll-pins", "#dpll-pin-cells")
DEFINE_SUFFIX_PROP(regulators, "-supply", NULL)
DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells")
@@ -1568,6 +1569,7 @@ static const struct supplier_bindings of_supplier_bindings[] = {
.parse_prop = parse_post_init_providers,
.fwlink_flags = FWLINK_FLAG_IGNORE,
},
+ { .parse_prop = parse_dpll_pins, },
{}
};
diff --git a/include/linux/dpll.h b/include/linux/dpll.h
index f0c31a111c304..755c36d1ef45a 100644
--- a/include/linux/dpll.h
+++ b/include/linux/dpll.h
@@ -11,6 +11,7 @@
#include <linux/device.h>
#include <linux/netlink.h>
#include <linux/netdevice.h>
+#include <linux/property.h>
#include <linux/rtnetlink.h>
struct dpll_device;
@@ -176,6 +177,8 @@ int dpll_netdev_add_pin_handle(struct sk_buff *msg,
const struct net_device *dev);
struct dpll_pin *fwnode_dpll_pin_find(struct fwnode_handle *fwnode);
+struct fwnode_handle *fwnode_dpll_pin_node_get(struct fwnode_handle *fwnode,
+ const char *name);
#else
static inline void
dpll_netdev_pin_set(struct net_device *dev, struct dpll_pin *dpll_pin) { }
@@ -197,8 +200,20 @@ fwnode_dpll_pin_find(struct fwnode_handle *fwnode)
{
return NULL;
}
+
+static inline struct fwnode_handle *
+fwnode_dpll_pin_node_get(struct fwnode_handle *fwnode, const char *name)
+{
+ return NULL;
+}
#endif
+static inline struct fwnode_handle *
+device_dpll_pin_node_get(struct device *dev, const char *name)
+{
+ return fwnode_dpll_pin_node_get(dev_fwnode(dev), name);
+}
+
struct dpll_device *
dpll_device_get(u64 clock_id, u32 dev_driver_id, struct module *module);
--
2.52.0On Fri, Jan 16, 2026 at 10:46 AM Ivan Vecera <ivecera@redhat.com> wrote:
>
> dpll: core: add helpers to find DPLL pin fwnode
>
> Add helper functions to the DPLL core to retrieve a DPLL pin's firmware
> node handle based on the 'dpll-pins' and 'dpll-pin-names' properties.
>
> Unlike simple phandle arrays, 'dpll-pins' entries typically contain
> a pin specifier (index and direction) as defined by '#dpll-pin-cells'.
> The new helper fwnode_dpll_pin_node_get() parses these specifiers
> using fwnode_property_get_reference_args(). It resolves the target
> pin by:
> 1. Identifying the DPLL device node from the phandle.
> 2. Selecting the correct sub-node ('input-pins' or 'output-pins') based
> on the direction argument.
> 3. Matching the pin index argument against the 'reg' property of
> the child nodes.
>
> Additionally, register 'dpll-pins' in drivers/of/property.c to enable
> proper parsing of the supplier bindings by the OF core.
>
> Signed-off-by: Ivan Vecera <ivecera@redhat.com>
> ---
> v2:
> * added check for fwnode_property_match_string() return value
> * reworked searching for the pin using dpll device phandle and
> pin specifier
> * added dpll-pins into OF core supplier_bindings
> ---
> drivers/dpll/dpll_core.c | 74 ++++++++++++++++++++++++++++++++++++++++
> drivers/of/property.c | 2 ++
> include/linux/dpll.h | 15 ++++++++
> 3 files changed, 91 insertions(+)
>
> diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c
> index fb68b5e19b480..b0083b5c10aa4 100644
> --- a/drivers/dpll/dpll_core.c
> +++ b/drivers/dpll/dpll_core.c
> @@ -13,6 +13,7 @@
> #include <linux/property.h>
> #include <linux/slab.h>
> #include <linux/string.h>
> +#include <dt-bindings/dpll/dpll.h>
>
> #include "dpll_core.h"
> #include "dpll_netlink.h"
> @@ -654,6 +655,79 @@ struct dpll_pin *fwnode_dpll_pin_find(struct fwnode_handle *fwnode)
> }
> EXPORT_SYMBOL_GPL(fwnode_dpll_pin_find);
>
> +/**
> + * fwnode_dpll_pin_node_get - get dpll pin node from given fw node and pin name
> + * @fwnode: firmware node that uses the dpll pin
> + * @name: dpll pin name from dpll-pin-names property
> + *
> + * Return: ERR_PTR() on error or a valid firmware node handle on success.
> + */
> +struct fwnode_handle *fwnode_dpll_pin_node_get(struct fwnode_handle *fwnode,
> + const char *name)
> +{
> + struct fwnode_handle *parent_node, *pin_node;
> + struct fwnode_reference_args args;
> + const char *parent_name;
> + int ret, index = 0;
> +
> + if (name) {
> + index = fwnode_property_match_string(fwnode, "dpll-pin-names",
> + name);
> + if (index < 0)
> + return ERR_PTR(-ENOENT);
> + }
> +
> + ret = fwnode_property_get_reference_args(fwnode, "dpll-pins",
> + "#dpll-pin-cells", 2, index,
> + &args);
> + if (ret)
> + return ERR_PTR(ret);
> +
> + /* We support only 2 cell DPLL bindings in the kernel currently. */
> + if (args.nargs != 2) {
> + fwnode_handle_put(args.fwnode);
> + return ERR_PTR(-ENOENT);
> + }
> +
> + /* Resolve parent node name according pin direction type */
> + switch (args.args[1]) {
> + case DPLL_PIN_INPUT:
> + parent_name = "input-pins";
> + break;
> + case DPLL_PIN_OUTPUT:
> + parent_name = "output-pins";
> + break;
> + default:
> + fwnode_handle_put(args.fwnode);
> + return ERR_PTR(-EINVAL);
> + }
> +
> + /* Get pin's parent sub-node */
> + parent_node = fwnode_get_named_child_node(args.fwnode, parent_name);
> + if (!parent_node) {
> + fwnode_handle_put(args.fwnode);
> + return ERR_PTR(-ENOENT);
> + }
> +
> + /* Enumerate child pin nodes and find the requested one */
> + fwnode_for_each_child_node(parent_node, pin_node) {
> + u32 reg;
> +
> + if (fwnode_property_read_u32(pin_node, "reg", ®))
> + continue;
> +
> + if (reg == args.args[0])
> + break;
> + }
> +
> + /* Release pin's parent and dpll device node */
> + fwnode_handle_put(parent_node);
> + fwnode_handle_put(args.fwnode);
> +
> + return pin_node ? pin_node : ERR_PTR(-ENOENT);
> +}
> +EXPORT_SYMBOL_GPL(fwnode_dpll_pin_node_get);
> +
> static int
> __dpll_pin_register(struct dpll_device *dpll, struct dpll_pin *pin,
> const struct dpll_pin_ops *ops, void *priv, void *cookie)
> diff --git a/drivers/of/property.c b/drivers/of/property.c
> index 4e3524227720a..8571c8bb71ade 100644
> --- a/drivers/of/property.c
> +++ b/drivers/of/property.c
> @@ -1410,6 +1410,7 @@ DEFINE_SIMPLE_PROP(post_init_providers, "post-init-providers", NULL)
> DEFINE_SIMPLE_PROP(access_controllers, "access-controllers", "#access-controller-cells")
> DEFINE_SIMPLE_PROP(pses, "pses", "#pse-cells")
> DEFINE_SIMPLE_PROP(power_supplies, "power-supplies", NULL)
> +DEFINE_SIMPLE_PROP(dpll_pins, "dpll-pins", "#dpll-pin-cells")
> DEFINE_SUFFIX_PROP(regulators, "-supply", NULL)
> DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells")
>
> @@ -1568,6 +1569,7 @@ static const struct supplier_bindings of_supplier_bindings[] = {
> .parse_prop = parse_post_init_providers,
> .fwlink_flags = FWLINK_FLAG_IGNORE,
> },
> + { .parse_prop = parse_dpll_pins, },
Keep the same order as the other table please.
-Saravana
> {}
> };
>
> diff --git a/include/linux/dpll.h b/include/linux/dpll.h
> index f0c31a111c304..755c36d1ef45a 100644
> --- a/include/linux/dpll.h
> +++ b/include/linux/dpll.h
> @@ -11,6 +11,7 @@
> #include <linux/device.h>
> #include <linux/netlink.h>
> #include <linux/netdevice.h>
> +#include <linux/property.h>
> #include <linux/rtnetlink.h>
>
> struct dpll_device;
> @@ -176,6 +177,8 @@ int dpll_netdev_add_pin_handle(struct sk_buff *msg,
> const struct net_device *dev);
>
> struct dpll_pin *fwnode_dpll_pin_find(struct fwnode_handle *fwnode);
> +struct fwnode_handle *fwnode_dpll_pin_node_get(struct fwnode_handle *fwnode,
> + const char *name);
> #else
> static inline void
> dpll_netdev_pin_set(struct net_device *dev, struct dpll_pin *dpll_pin) { }
> @@ -197,8 +200,20 @@ fwnode_dpll_pin_find(struct fwnode_handle *fwnode)
> {
> return NULL;
> }
> +
> +static inline struct fwnode_handle *
> +fwnode_dpll_pin_node_get(struct fwnode_handle *fwnode, const char *name)
> +{
> + return NULL;
> +}
> #endif
>
> +static inline struct fwnode_handle *
> +device_dpll_pin_node_get(struct device *dev, const char *name)
> +{
> + return fwnode_dpll_pin_node_get(dev_fwnode(dev), name);
> +}
> +
> struct dpll_device *
> dpll_device_get(u64 clock_id, u32 dev_driver_id, struct module *module);
>
> --
> 2.52.0
>
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