Extend the DPLL core to support associating a DPLL pin with a firmware node. This association is required to allow other subsystems (such as network drivers) to locate and request specific DPLL pins defined in the Device Tree or ACPI.
* Add a .fwnode field to the struct dpll_pin * Introduce dpll_pin_fwnode_set() helper to allow the provider driver to associate a pin with a fwnode after the pin has been allocated * Introduce fwnode_dpll_pin_find() helper to allow consumers to search for a registered DPLL pin using its associated fwnode handle * Ensure the fwnode reference is properly released in dpll_pin_put() Signed-off-by: Ivan Vecera <[email protected]> --- Changes: RFC v2: - dpll_pin_fwnode_set() helper to set firmware node without touching dpll_pin_get() --- drivers/dpll/dpll_core.c | 49 ++++++++++++++++++++++++++++++++++++++++ drivers/dpll/dpll_core.h | 2 ++ include/linux/dpll.h | 11 +++++++++ 3 files changed, 62 insertions(+) diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c index a461095efd8ac..fb68b5e19b480 100644 --- a/drivers/dpll/dpll_core.c +++ b/drivers/dpll/dpll_core.c @@ -10,6 +10,7 @@ #include <linux/device.h> #include <linux/err.h> +#include <linux/property.h> #include <linux/slab.h> #include <linux/string.h> @@ -599,12 +600,60 @@ void dpll_pin_put(struct dpll_pin *pin) xa_destroy(&pin->parent_refs); xa_destroy(&pin->ref_sync_pins); dpll_pin_prop_free(&pin->prop); + fwnode_handle_put(pin->fwnode); kfree_rcu(pin, rcu); } mutex_unlock(&dpll_lock); } EXPORT_SYMBOL_GPL(dpll_pin_put); +/** + * dpll_pin_fwnode_set - set dpll pin firmware node reference + * @pin: pointer to a dpll pin + * @fwnode: firmware node handle + * + * Set firmware node handle for the given dpll pin. + */ +void dpll_pin_fwnode_set(struct dpll_pin *pin, struct fwnode_handle *fwnode) +{ + mutex_lock(&dpll_lock); + fwnode_handle_put(pin->fwnode); /* Drop fwnode previously set */ + pin->fwnode = fwnode_handle_get(fwnode); + mutex_unlock(&dpll_lock); +} +EXPORT_SYMBOL_GPL(dpll_pin_fwnode_set); + +/** + * fwnode_dpll_pin_find - find dpll pin by firmware node reference + * @fwnode: reference to firmware node + * + * Get existing object of a pin that is associated with given firmware node + * reference. + * + * Context: Acquires a lock (dpll_lock) + * Return: + * * valid dpll_pin struct pointer if succeeded + * * ERR_PTR(X) - error + */ +struct dpll_pin *fwnode_dpll_pin_find(struct fwnode_handle *fwnode) +{ + struct dpll_pin *pin, *ret = NULL; + unsigned long index; + + mutex_lock(&dpll_lock); + xa_for_each(&dpll_pin_xa, index, pin) { + if (pin->fwnode == fwnode) { + ret = pin; + refcount_inc(&ret->refcount); + break; + } + } + mutex_unlock(&dpll_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(fwnode_dpll_pin_find); + 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/dpll/dpll_core.h b/drivers/dpll/dpll_core.h index 8ce969bbeb64e..d3e17ff0ecef0 100644 --- a/drivers/dpll/dpll_core.h +++ b/drivers/dpll/dpll_core.h @@ -42,6 +42,7 @@ struct dpll_device { * @pin_idx: index of a pin given by dev driver * @clock_id: clock_id of creator * @module: module of creator + * @fwnode: optional reference to firmware node * @dpll_refs: hold referencees to dplls pin was registered with * @parent_refs: hold references to parent pins pin was registered with * @ref_sync_pins: hold references to pins for Reference SYNC feature @@ -54,6 +55,7 @@ struct dpll_pin { u32 pin_idx; u64 clock_id; struct module *module; + struct fwnode_handle *fwnode; struct xarray dpll_refs; struct xarray parent_refs; struct xarray ref_sync_pins; diff --git a/include/linux/dpll.h b/include/linux/dpll.h index 562f520b23c27..f0c31a111c304 100644 --- a/include/linux/dpll.h +++ b/include/linux/dpll.h @@ -16,6 +16,7 @@ struct dpll_device; struct dpll_pin; struct dpll_pin_esync; +struct fwnode_handle; struct dpll_device_ops { int (*mode_get)(const struct dpll_device *dpll, void *dpll_priv, @@ -173,6 +174,8 @@ void dpll_netdev_pin_clear(struct net_device *dev); size_t dpll_netdev_pin_handle_size(const struct net_device *dev); 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); #else static inline void dpll_netdev_pin_set(struct net_device *dev, struct dpll_pin *dpll_pin) { } @@ -188,6 +191,12 @@ dpll_netdev_add_pin_handle(struct sk_buff *msg, const struct net_device *dev) { return 0; } + +static inline struct dpll_pin * +fwnode_dpll_pin_find(struct fwnode_handle *fwnode) +{ + return NULL; +} #endif struct dpll_device * @@ -213,6 +222,8 @@ void dpll_pin_unregister(struct dpll_device *dpll, struct dpll_pin *pin, void dpll_pin_put(struct dpll_pin *pin); +void dpll_pin_fwnode_set(struct dpll_pin *pin, struct fwnode_handle *fwnode); + int dpll_pin_on_pin_register(struct dpll_pin *parent, struct dpll_pin *pin, const struct dpll_pin_ops *ops, void *priv); -- 2.52.0
