[PATCH net-next v2 03/12] dpll: Add helpers to find DPLL pin fwnode
From: Ivan Vecera <ivecera@redhat.com>
Date: 2026-01-16 18:46:54
Also in:
intel-wired-lan, linux-devicetree, linux-rdma, lkml
Subsystem:
dpll subsystem, open firmware and flattened device tree, the rest · Maintainers:
Vadim Fedorenko, Arkadiusz Kubalewski, Jiri Pirko, Rob Herring, Saravana Kannan, Linus Torvalds
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);
--
2.52.0