new file mode 100644
@@ -0,0 +1,976 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * dpll_core.c - DPLL subsystem kernel-space interface implementation.
+ *
+ * Copyright (c) 2023 Meta Platforms, Inc. and affiliates
+ * Copyright (c) 2023 Intel Corporation.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+#include "dpll_core.h"
+
+DEFINE_MUTEX(dpll_lock);
+
+DEFINE_XARRAY_FLAGS(dpll_device_xa, XA_FLAGS_ALLOC);
+DEFINE_XARRAY_FLAGS(dpll_pin_xa, XA_FLAGS_ALLOC);
+
+#define ASSERT_DPLL_REGISTERED(d) \
+ WARN_ON_ONCE(!xa_get_mark(&dpll_device_xa, (d)->id, DPLL_REGISTERED))
+#define ASSERT_DPLL_NOT_REGISTERED(d) \
+ WARN_ON_ONCE(xa_get_mark(&dpll_device_xa, (d)->id, DPLL_REGISTERED))
+
+struct dpll_device_registration {
+ struct list_head list;
+ const struct dpll_device_ops *ops;
+ void *priv;
+};
+
+struct dpll_pin_registration {
+ struct list_head list;
+ const struct dpll_pin_ops *ops;
+ void *priv;
+};
+
+/**
+ * dpll_device_get_by_id - find dpll device by it's id
+ * @id: id of searched dpll
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return:
+ * * dpll_device struct if found
+ * * NULL otherwise
+ */
+struct dpll_device *dpll_device_get_by_id(int id)
+{
+ if (xa_get_mark(&dpll_device_xa, id, DPLL_REGISTERED))
+ return xa_load(&dpll_device_xa, id);
+
+ return NULL;
+}
+
+/**
+ * dpll_pin_registration_find - find a pin registration record
+ * @ref: reference between dpll and pin
+ * @ops: searched pin ops pointer
+ * @priv: searched pin priv pointer
+ *
+ * Search dpll's registered pins for given ops and priv data.
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return:
+ * * NULL - if pin was not found
+ * * pointer to `struct dpll_pin_registration` if found
+ */
+static struct dpll_pin_registration *
+dpll_pin_registration_find(struct dpll_pin_ref *ref,
+ const struct dpll_pin_ops *ops, void *priv)
+{
+ struct dpll_pin_registration *reg;
+
+ list_for_each_entry(reg, &ref->registration_list, list) {
+ if (reg->ops == ops && reg->priv == priv)
+ return reg;
+ }
+ return NULL;
+}
+
+/**
+ * dpll_xa_ref_pin_add - add pin reference to a given xarray
+ * @xa_pins: dpll_pin_ref xarray holding pins
+ * @pin: pin being added
+ * @ops: ops for a pin
+ * @priv: pointer to private data of owner
+ *
+ * Allocate and create reference of a pin and enlist a registration
+ * structure storing ops and priv pointers of a caller registant.
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return:
+ * * 0 on success
+ * * -ENOMEM on failed allocation
+ */
+static int
+dpll_xa_ref_pin_add(struct xarray *xa_pins, struct dpll_pin *pin,
+ const struct dpll_pin_ops *ops, void *priv)
+{
+ struct dpll_pin_registration *reg;
+ struct dpll_pin_ref *ref;
+ bool ref_exists = false;
+ unsigned long i;
+ int ret;
+
+ xa_for_each(xa_pins, i, ref) {
+ if (ref->pin != pin)
+ continue;
+ reg = dpll_pin_registration_find(ref, ops, priv);
+ if (reg) {
+ refcount_inc(&ref->refcount);
+ return 0;
+ }
+ ref_exists = true;
+ break;
+ }
+
+ if (!ref_exists) {
+ ref = kzalloc(sizeof(*ref), GFP_KERNEL);
+ if (!ref)
+ return -ENOMEM;
+ ref->pin = pin;
+ INIT_LIST_HEAD(&ref->registration_list);
+ ret = xa_insert(xa_pins, pin->pin_idx, ref, GFP_KERNEL);
+ if (ret) {
+ kfree(ref);
+ return ret;
+ }
+ refcount_set(&ref->refcount, 1);
+ }
+
+ reg = kzalloc(sizeof(*reg), GFP_KERNEL);
+ if (!reg) {
+ if (!ref_exists) {
+ xa_erase(xa_pins, pin->pin_idx);
+ kfree(ref);
+ }
+ return -ENOMEM;
+ }
+ reg->ops = ops;
+ reg->priv = priv;
+ refcount_inc(&ref->refcount);
+ list_add_tail(®->list, &ref->registration_list);
+
+ return 0;
+}
+
+/**
+ * dpll_xa_ref_pin_del - remove reference of a pin from xarray
+ * @xa_pins: dpll_pin_ref xarray holding pins
+ * @pin: pointer to a pin being removed
+ * @ops: pointer to ops of pin being removed
+ * @priv: pointer to private data of registerer who invoked pin removal
+ *
+ * Decrement refcount of existing pin reference on given xarray.
+ * If all registrations are lifted delete the reference and free its memory.
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return:
+ * * 0 on success
+ * * -EINVAL if reference to a pin was not found
+ */
+static int dpll_xa_ref_pin_del(struct xarray *xa_pins, struct dpll_pin *pin,
+ const struct dpll_pin_ops *ops, void *priv)
+{
+ struct dpll_pin_registration *reg;
+ struct dpll_pin_ref *ref;
+ unsigned long i;
+
+ xa_for_each(xa_pins, i, ref) {
+ if (ref->pin != pin)
+ continue;
+ reg = dpll_pin_registration_find(ref, ops, priv);
+ if (WARN_ON(!reg))
+ return -EINVAL;
+ if (refcount_dec_and_test(&ref->refcount)) {
+ list_del(®->list);
+ kfree(reg);
+ xa_erase(xa_pins, i);
+ WARN_ON(!list_empty(&ref->registration_list));
+ kfree(ref);
+ }
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+/**
+ * dpll_xa_ref_dpll_add - add dpll reference to a given xarray
+ * @xa_dplls: dpll_pin_ref xarray holding dplls
+ * @dpll: dpll being added
+ * @ops: pin-reference ops for a dpll
+ * @priv: pointer to private data of owner
+ *
+ * Allocate and create reference of a dpll-pin ops or increase refcount
+ * on existing dpll reference on given xarray.
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return:
+ * * 0 on success
+ * * -ENOMEM on failed allocation
+ */
+static int
+dpll_xa_ref_dpll_add(struct xarray *xa_dplls, struct dpll_device *dpll,
+ const struct dpll_pin_ops *ops, void *priv)
+{
+ struct dpll_pin_registration *reg;
+ struct dpll_pin_ref *ref;
+ bool ref_exists = false;
+ unsigned long i;
+ int ret;
+
+ xa_for_each(xa_dplls, i, ref) {
+ if (ref->dpll != dpll)
+ continue;
+ reg = dpll_pin_registration_find(ref, ops, priv);
+ if (reg) {
+ refcount_inc(&ref->refcount);
+ return 0;
+ }
+ ref_exists = true;
+ break;
+ }
+
+ if (!ref_exists) {
+ ref = kzalloc(sizeof(*ref), GFP_KERNEL);
+ if (!ref)
+ return -ENOMEM;
+ ref->dpll = dpll;
+ INIT_LIST_HEAD(&ref->registration_list);
+ ret = xa_insert(xa_dplls, dpll->device_idx, ref, GFP_KERNEL);
+ if (ret) {
+ kfree(ref);
+ return ret;
+ }
+ refcount_set(&ref->refcount, 1);
+ }
+
+ reg = kzalloc(sizeof(*reg), GFP_KERNEL);
+ if (!reg) {
+ if (!ref_exists) {
+ xa_erase(xa_dplls, dpll->device_idx);
+ kfree(ref);
+ }
+ return -ENOMEM;
+ }
+ reg->ops = ops;
+ reg->priv = priv;
+ refcount_inc(&ref->refcount);
+ list_add_tail(®->list, &ref->registration_list);
+
+ return 0;
+}
+
+/**
+ * dpll_xa_ref_dpll_del - remove reference of a dpll from xarray
+ * @xa_dplls: dpll_pin_ref xarray holding dplls
+ * @dpll: pointer to a dpll to remove
+ * @ops: pointer to ops of dpll being removed
+ * @priv: pointer to private data of registerer who invoked dpll removal
+ *
+ * Decrement refcount of existing dpll reference on given xarray.
+ * If all references are dropped, delete the reference and free its memory.
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ */
+static void
+dpll_xa_ref_dpll_del(struct xarray *xa_dplls, struct dpll_device *dpll,
+ const struct dpll_pin_ops *ops, void *priv)
+{
+ struct dpll_pin_registration *reg;
+ struct dpll_pin_ref *ref;
+ unsigned long i;
+
+ xa_for_each(xa_dplls, i, ref) {
+ if (ref->dpll != dpll)
+ continue;
+ reg = dpll_pin_registration_find(ref, ops, priv);
+ if (WARN_ON(!reg))
+ return;
+ if (refcount_dec_and_test(&ref->refcount)) {
+ list_del(®->list);
+ kfree(reg);
+ xa_erase(xa_dplls, i);
+ WARN_ON(!list_empty(&ref->registration_list));
+ kfree(ref);
+ }
+ return;
+ }
+}
+
+/**
+ * dpll_xa_ref_dpll_find - find dpll reference on xarray
+ * @xa_refs: dpll_pin_ref xarray holding dpll references
+ * @dpll: pointer to a dpll being searched
+ *
+ * Search for dpll-pin ops reference struct of a given dpll on given xarray.
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return:
+ * * pin reference struct pointer on success
+ * * NULL - reference to a pin was not found
+ */
+struct dpll_pin_ref *
+dpll_xa_ref_dpll_find(struct xarray *xa_refs, const struct dpll_device *dpll)
+{
+ struct dpll_pin_ref *ref;
+ unsigned long i;
+
+ xa_for_each(xa_refs, i, ref)
+ if (ref->dpll == dpll)
+ return ref;
+
+ return NULL;
+}
+
+/**
+ * dpll_xa_ref_dpll_first - find first record of given xarray
+ * @xa_refs: xarray
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return: first element on given xaaray
+ */
+struct dpll_pin_ref *dpll_xa_ref_dpll_first(struct xarray *xa_refs)
+{
+ struct dpll_pin_ref *ref;
+ unsigned long i = 0;
+
+ ref = xa_find(xa_refs, &i, ULONG_MAX, XA_PRESENT);
+ WARN_ON(!ref);
+ return ref;
+}
+
+/**
+ * dpll_device_alloc - allocate the memory for dpll device
+ * @clock_id: clock_id of creator
+ * @device_idx: id given by dev driver
+ * @module: reference to registering module
+ *
+ * Allocates memory and initialize dpll device, hold its reference on global
+ * xarray.
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return:
+ * * valid dpll_device struct pointer if succeeded
+ * * ERR_PTR(-ENOMEM) - failed memory allocation
+ * * ERR_PTR(X) - failed allocation on dpll's xa
+ */
+static struct dpll_device *
+dpll_device_alloc(const u64 clock_id, u32 device_idx, struct module *module)
+{
+ struct dpll_device *dpll;
+ int ret;
+
+ dpll = kzalloc(sizeof(*dpll), GFP_KERNEL);
+ if (!dpll)
+ return ERR_PTR(-ENOMEM);
+ refcount_set(&dpll->refcount, 1);
+ INIT_LIST_HEAD(&dpll->registration_list);
+ dpll->device_idx = device_idx;
+ dpll->clock_id = clock_id;
+ dpll->module = module;
+ ret = xa_alloc(&dpll_device_xa, &dpll->id, dpll, xa_limit_16b,
+ GFP_KERNEL);
+ if (ret) {
+ kfree(dpll);
+ return ERR_PTR(ret);
+ }
+ xa_init_flags(&dpll->pin_refs, XA_FLAGS_ALLOC);
+
+ return dpll;
+}
+
+/**
+ * dpll_device_get - find existing or create new dpll device
+ * @clock_id: clock_id of creator
+ * @device_idx: idx given by device driver
+ * @module: reference to registering module
+ *
+ * Get existing object of a dpll device, unique for given arguments.
+ * Create new if doesn't exist yet.
+ *
+ * Context: Acquires a lock (dpll_lock)
+ * Return:
+ * * valid dpll_device struct pointer if succeeded
+ * * ERR_PTR(-ENOMEM) - failed memory allocation
+ * * ERR_PTR(X) - failed allocation on dpll's xa
+ */
+struct dpll_device *
+dpll_device_get(u64 clock_id, u32 device_idx, struct module *module)
+{
+ struct dpll_device *dpll, *ret = NULL;
+ unsigned long index;
+
+ mutex_lock(&dpll_lock);
+ xa_for_each(&dpll_device_xa, index, dpll) {
+ if (dpll->clock_id == clock_id &&
+ dpll->device_idx == device_idx &&
+ dpll->module == module) {
+ ret = dpll;
+ refcount_inc(&ret->refcount);
+ break;
+ }
+ }
+ if (!ret)
+ ret = dpll_device_alloc(clock_id, device_idx, module);
+ mutex_unlock(&dpll_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dpll_device_get);
+
+/**
+ * dpll_device_put - decrease the refcount and free memory if possible
+ * @dpll: dpll_device struct pointer
+ *
+ * Context: Acquires a lock (dpll_lock)
+ * Drop reference for a dpll device, if all references are gone, delete
+ * dpll device object.
+ */
+void dpll_device_put(struct dpll_device *dpll)
+{
+ mutex_lock(&dpll_lock);
+ if (refcount_dec_and_test(&dpll->refcount)) {
+ ASSERT_DPLL_NOT_REGISTERED(dpll);
+ WARN_ON_ONCE(!xa_empty(&dpll->pin_refs));
+ xa_destroy(&dpll->pin_refs);
+ xa_erase(&dpll_device_xa, dpll->id);
+ WARN_ON(!list_empty(&dpll->registration_list));
+ kfree(dpll);
+ }
+ mutex_unlock(&dpll_lock);
+}
+EXPORT_SYMBOL_GPL(dpll_device_put);
+
+static struct dpll_device_registration *
+dpll_device_registration_find(struct dpll_device *dpll,
+ const struct dpll_device_ops *ops, void *priv)
+{
+ struct dpll_device_registration *reg;
+
+ list_for_each_entry(reg, &dpll->registration_list, list) {
+ if (reg->ops == ops && reg->priv == priv)
+ return reg;
+ }
+ return NULL;
+}
+
+/**
+ * dpll_device_register - register the dpll device in the subsystem
+ * @dpll: pointer to a dpll
+ * @type: type of a dpll
+ * @ops: ops for a dpll device
+ * @priv: pointer to private information of owner
+ *
+ * Make dpll device available for user space.
+ *
+ * Context: Acquires a lock (dpll_lock)
+ * Return:
+ * * 0 on success
+ * * -EINVAL on failure due to wrong arguments provided
+ * * -EEXIST if device was already registered
+ * * -ENOMEM failed to allocate memory
+ */
+int dpll_device_register(struct dpll_device *dpll, enum dpll_type type,
+ const struct dpll_device_ops *ops, void *priv)
+{
+ struct dpll_device_registration *reg;
+ bool first_registration = false;
+
+ if (WARN_ON(!ops))
+ return -EINVAL;
+ if (WARN_ON(!ops->mode_get))
+ return -EINVAL;
+ if (WARN_ON(!ops->lock_status_get))
+ return -EINVAL;
+ if (WARN_ON(type < DPLL_TYPE_PPS || type > DPLL_TYPE_MAX))
+ return -EINVAL;
+
+ mutex_lock(&dpll_lock);
+ reg = dpll_device_registration_find(dpll, ops, priv);
+ if (reg) {
+ mutex_unlock(&dpll_lock);
+ return -EEXIST;
+ }
+
+ reg = kzalloc(sizeof(*reg), GFP_KERNEL);
+ if (!reg) {
+ mutex_unlock(&dpll_lock);
+ return -ENOMEM;
+ }
+ reg->ops = ops;
+ reg->priv = priv;
+ dpll->type = type;
+ first_registration = list_empty(&dpll->registration_list);
+ list_add_tail(®->list, &dpll->registration_list);
+ if (!first_registration) {
+ mutex_unlock(&dpll_lock);
+ return 0;
+ }
+
+ xa_set_mark(&dpll_device_xa, dpll->id, DPLL_REGISTERED);
+ mutex_unlock(&dpll_lock);
+ dpll_device_create_ntf(dpll);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dpll_device_register);
+
+/**
+ * dpll_device_unregister - unregister dpll device
+ * @dpll: registered dpll pointer
+ * @ops: ops for a dpll device
+ * @priv: pointer to private information of owner
+ *
+ * Unregister device, make it unavailable for userspace.
+ * Note: It does not free the memory
+ * Context: Acquires a lock (dpll_lock)
+ */
+void dpll_device_unregister(struct dpll_device *dpll,
+ const struct dpll_device_ops *ops, void *priv)
+{
+ struct dpll_device_registration *reg;
+
+ mutex_lock(&dpll_lock);
+ ASSERT_DPLL_REGISTERED(dpll);
+ dpll_device_delete_ntf(dpll);
+ reg = dpll_device_registration_find(dpll, ops, priv);
+ if (WARN_ON(!reg)) {
+ mutex_unlock(&dpll_lock);
+ return;
+ }
+ list_del(®->list);
+ kfree(reg);
+
+ if (!list_empty(&dpll->registration_list)) {
+ mutex_unlock(&dpll_lock);
+ return;
+ }
+ xa_clear_mark(&dpll_device_xa, dpll->id, DPLL_REGISTERED);
+ mutex_unlock(&dpll_lock);
+}
+EXPORT_SYMBOL_GPL(dpll_device_unregister);
+
+/**
+ * dpll_pin_alloc - allocate the memory for dpll pin
+ * @clock_id: clock_id of creator
+ * @pin_idx: idx given by dev driver
+ * @module: reference to registering module
+ * @prop: dpll pin properties
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return:
+ * * valid allocated dpll_pin struct pointer if succeeded
+ * * ERR_PTR(-ENOMEM) - failed memory allocation
+ * * ERR_PTR(-EINVAL) - wrong pin type property value
+ */
+static struct dpll_pin *
+dpll_pin_alloc(u64 clock_id, u32 pin_idx, struct module *module,
+ const struct dpll_pin_properties *prop)
+{
+ struct dpll_pin *pin;
+ int ret;
+
+ pin = kzalloc(sizeof(*pin), GFP_KERNEL);
+ if (!pin)
+ return ERR_PTR(-ENOMEM);
+ pin->pin_idx = pin_idx;
+ pin->clock_id = clock_id;
+ pin->module = module;
+ if (WARN_ON(prop->type < DPLL_PIN_TYPE_MUX ||
+ prop->type > DPLL_PIN_TYPE_MAX)) {
+ ret = -EINVAL;
+ goto err;
+ }
+ pin->prop = prop;
+ refcount_set(&pin->refcount, 1);
+ xa_init_flags(&pin->dpll_refs, XA_FLAGS_ALLOC);
+ xa_init_flags(&pin->parent_refs, XA_FLAGS_ALLOC);
+ ret = xa_alloc(&dpll_pin_xa, &pin->id, pin, xa_limit_16b, GFP_KERNEL);
+ if (ret)
+ goto err;
+ return pin;
+err:
+ xa_destroy(&pin->dpll_refs);
+ xa_destroy(&pin->parent_refs);
+ kfree(pin);
+ return ERR_PTR(ret);
+}
+
+/**
+ * dpll_pin_get - find existing or create new dpll pin
+ * @clock_id: clock_id of creator
+ * @pin_idx: idx given by dev driver
+ * @module: reference to registering module
+ * @prop: dpll pin properties
+ *
+ * Get existing object of a pin (unique for given arguments) or create new
+ * if doesn't exist yet.
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return:
+ * * valid allocated dpll_pin struct pointer if succeeded
+ * * ERR_PTR of an error
+ */
+struct dpll_pin *
+dpll_pin_get(u64 clock_id, u32 pin_idx, struct module *module,
+ const struct dpll_pin_properties *prop)
+{
+ struct dpll_pin *pos, *ret = NULL;
+ unsigned long i;
+
+ xa_for_each(&dpll_pin_xa, i, pos) {
+ if (pos->clock_id == clock_id &&
+ pos->pin_idx == pin_idx &&
+ pos->module == module) {
+ ret = pos;
+ refcount_inc(&ret->refcount);
+ break;
+ }
+ }
+ if (!ret)
+ ret = dpll_pin_alloc(clock_id, pin_idx, module, prop);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dpll_pin_get);
+
+/**
+ * dpll_pin_put - decrease the refcount and free memory if possible
+ * @pin: pointer to a pin to be put
+ *
+ * Drop reference for a pin, if all references are gone, delete pin object.
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ */
+void dpll_pin_put(struct dpll_pin *pin)
+{
+ if (refcount_dec_and_test(&pin->refcount)) {
+ xa_destroy(&pin->dpll_refs);
+ xa_destroy(&pin->parent_refs);
+ xa_erase(&dpll_pin_xa, pin->id);
+ kfree(pin);
+ }
+}
+EXPORT_SYMBOL_GPL(dpll_pin_put);
+
+static int
+__dpll_pin_register(struct dpll_device *dpll, struct dpll_pin *pin,
+ const struct dpll_pin_ops *ops, void *priv)
+{
+ int ret;
+
+ ret = dpll_xa_ref_pin_add(&dpll->pin_refs, pin, ops, priv);
+ if (ret)
+ return ret;
+ ret = dpll_xa_ref_dpll_add(&pin->dpll_refs, dpll, ops, priv);
+ if (ret)
+ goto ref_pin_del;
+ xa_set_mark(&dpll_pin_xa, pin->id, DPLL_REGISTERED);
+ dpll_pin_create_ntf(pin);
+
+ return ret;
+
+ref_pin_del:
+ dpll_xa_ref_pin_del(&dpll->pin_refs, pin, ops, priv);
+ return ret;
+}
+
+/**
+ * dpll_pin_register - register the dpll pin in the subsystem
+ * @dpll: pointer to a dpll
+ * @pin: pointer to a dpll pin
+ * @ops: ops for a dpll pin ops
+ * @priv: pointer to private information of owner
+ *
+ * Context: Acquires a lock (dpll_lock)
+ * Return:
+ * * 0 on success
+ * * -EINVAL - missing pin ops or module/clock_id mismatch
+ * * -ENOMEM - failed to allocate memory
+ */
+int
+dpll_pin_register(struct dpll_device *dpll, struct dpll_pin *pin,
+ const struct dpll_pin_ops *ops, void *priv)
+{
+ int ret;
+
+ if (WARN_ON(!ops) ||
+ WARN_ON(!ops->state_on_dpll_get) ||
+ WARN_ON(!ops->direction_get))
+ return -EINVAL;
+
+ mutex_lock(&dpll_lock);
+ if (WARN_ON(!(dpll->module == pin->module &&
+ dpll->clock_id == pin->clock_id)))
+ ret = -EINVAL;
+ else
+ ret = __dpll_pin_register(dpll, pin, ops, priv);
+ mutex_unlock(&dpll_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dpll_pin_register);
+
+static void
+__dpll_pin_unregister(struct dpll_device *dpll, struct dpll_pin *pin,
+ const struct dpll_pin_ops *ops, void *priv)
+{
+ dpll_xa_ref_pin_del(&dpll->pin_refs, pin, ops, priv);
+ dpll_xa_ref_dpll_del(&pin->dpll_refs, dpll, ops, priv);
+ if (xa_empty(&pin->dpll_refs))
+ xa_clear_mark(&dpll_pin_xa, pin->id, DPLL_REGISTERED);
+}
+
+/**
+ * dpll_pin_unregister - unregister dpll pin from dpll device
+ * @dpll: registered dpll pointer
+ * @pin: pointer to a pin
+ * @ops: ops for a dpll pin
+ * @priv: pointer to private information of owner
+ *
+ * Note: It does not free the memory
+ * Context: Acquires a lock (dpll_lock)
+ */
+void dpll_pin_unregister(struct dpll_device *dpll, struct dpll_pin *pin,
+ const struct dpll_pin_ops *ops, void *priv)
+{
+ if (WARN_ON(xa_empty(&dpll->pin_refs)))
+ return;
+
+ mutex_lock(&dpll_lock);
+ __dpll_pin_unregister(dpll, pin, ops, priv);
+ mutex_unlock(&dpll_lock);
+}
+EXPORT_SYMBOL_GPL(dpll_pin_unregister);
+
+/**
+ * dpll_pin_on_pin_register - register a pin with a parent pin
+ * @parent: pointer to a parent pin
+ * @pin: pointer to a pin
+ * @ops: ops for a dpll pin
+ * @priv: pointer to private information of owner
+ *
+ * Register a pin with a parent pin, create references between them and
+ * between newly registered pin and dplls connected with a parent pin.
+ *
+ * Context: Acquires a lock (dpll_lock)
+ * Return:
+ * * 0 on success
+ * * -EINVAL missing pin or parent
+ * * -ENOMEM failed allocation
+ * * -EPERM if parent is not allowed
+ */
+int dpll_pin_on_pin_register(struct dpll_pin *parent, struct dpll_pin *pin,
+ const struct dpll_pin_ops *ops, void *priv)
+{
+ struct dpll_pin_ref *ref;
+ unsigned long i, stop;
+ int ret;
+
+ if (WARN_ON(parent->prop->type != DPLL_PIN_TYPE_MUX))
+ return -EINVAL;
+
+ if (WARN_ON(!ops) ||
+ WARN_ON(!ops->state_on_pin_get) ||
+ WARN_ON(!ops->direction_get))
+ return -EINVAL;
+
+ ret = dpll_xa_ref_pin_add(&pin->parent_refs, parent, ops, priv);
+ if (ret)
+ goto unlock;
+ refcount_inc(&pin->refcount);
+ xa_for_each(&parent->dpll_refs, i, ref) {
+ mutex_lock(&dpll_lock);
+ ret = __dpll_pin_register(ref->dpll, pin, ops, priv);
+ mutex_unlock(&dpll_lock);
+ if (ret) {
+ stop = i;
+ goto dpll_unregister;
+ }
+ dpll_pin_create_ntf(pin);
+ }
+
+ return ret;
+
+dpll_unregister:
+ xa_for_each(&parent->dpll_refs, i, ref) {
+ if (i < stop) {
+ mutex_lock(&dpll_lock);
+ __dpll_pin_unregister(ref->dpll, pin, ops, priv);
+ mutex_unlock(&dpll_lock);
+ }
+ }
+ refcount_dec(&pin->refcount);
+ dpll_xa_ref_pin_del(&pin->parent_refs, parent, ops, priv);
+unlock:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dpll_pin_on_pin_register);
+
+/**
+ * dpll_pin_on_pin_unregister - unregister dpll pin from a parent pin
+ * @parent: pointer to a parent pin
+ * @pin: pointer to a pin
+ * @ops: ops for a dpll pin
+ * @priv: pointer to private information of owner
+ *
+ * Context: Acquires a lock (dpll_lock)
+ * Note: It does not free the memory
+ */
+void dpll_pin_on_pin_unregister(struct dpll_pin *parent, struct dpll_pin *pin,
+ const struct dpll_pin_ops *ops, void *priv)
+{
+ struct dpll_pin_ref *ref;
+ unsigned long i;
+
+ mutex_lock(&dpll_lock);
+ dpll_pin_delete_ntf(pin);
+ dpll_xa_ref_pin_del(&pin->parent_refs, parent, ops, priv);
+ refcount_dec(&pin->refcount);
+ xa_for_each(&pin->dpll_refs, i, ref)
+ __dpll_pin_unregister(ref->dpll, pin, ops, priv);
+ mutex_unlock(&dpll_lock);
+}
+EXPORT_SYMBOL_GPL(dpll_pin_on_pin_unregister);
+
+
+/**
+ * dpll_device_registration_first - get first registration of dpll device
+ * @dpll: pointer to a dpll
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return: pointer to the first registration of a dpll
+ */
+static struct dpll_device_registration *
+dpll_device_registration_first(struct dpll_device *dpll)
+{
+ struct dpll_device_registration *reg;
+
+ reg = list_first_entry_or_null((struct list_head *) &dpll->registration_list,
+ struct dpll_device_registration, list);
+ WARN_ON(!reg);
+ return reg;
+}
+
+/**
+ * dpll_priv - get the dpll device private owner data
+ * @dpll: registered dpll pointer
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return: pointer to the first registration priv data
+ */
+void *dpll_priv(struct dpll_device *dpll)
+{
+ struct dpll_device_registration *reg;
+
+ reg = dpll_device_registration_first(dpll);
+ return reg->priv;
+}
+
+/**
+ * dpll_device_ops - get the dpll device ops pointer
+ * @dpll: registered dpll pointer
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return: pointer to the first registration ops of the dpll
+ */
+const struct dpll_device_ops *dpll_device_ops(struct dpll_device *dpll)
+{
+ struct dpll_device_registration *reg;
+
+ reg = dpll_device_registration_first(dpll);
+ return reg->ops;
+}
+
+/**
+ * dpll_pin_registration_first - get first registration of dpll pin ref
+ * @ref: pointer to a pin ref struct
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return: pointer to the first registration of a dpll_pin_ref
+ */
+static struct dpll_pin_registration *
+dpll_pin_registration_first(struct dpll_pin_ref *ref)
+{
+ struct dpll_pin_registration *reg;
+
+ reg = list_first_entry_or_null(&ref->registration_list,
+ struct dpll_pin_registration, list);
+ WARN_ON(!reg);
+ return reg;
+}
+
+/**
+ * dpll_pin_on_dpll_priv - get the dpll device private owner data
+ * @dpll: registered dpll pointer
+ * @pin: pointer to a pin
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return: pointer to the data
+ */
+void *dpll_pin_on_dpll_priv(struct dpll_device *dpll,
+ struct dpll_pin *pin)
+{
+ struct dpll_pin_registration *reg;
+ struct dpll_pin_ref *ref;
+
+ ref = xa_load(&dpll->pin_refs, pin->pin_idx);
+ if (!ref)
+ return NULL;
+ reg = dpll_pin_registration_first(ref);
+ return reg->priv;
+}
+
+/**
+ * dpll_pin_on_pin_priv - get the dpll pin private owner data
+ * @parent: pointer to a parent pin
+ * @pin: pointer to a pin
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return: pointer to the data
+ */
+void *dpll_pin_on_pin_priv(struct dpll_pin *parent,
+ struct dpll_pin *pin)
+{
+ struct dpll_pin_registration *reg;
+ struct dpll_pin_ref *ref;
+
+ ref = xa_load(&pin->parent_refs, parent->pin_idx);
+ if (!ref)
+ return NULL;
+ reg = dpll_pin_registration_first(ref);
+ return reg->priv;
+}
+
+/**
+ * dpll_pin_ops - get the pin ops pointer
+ * @ref: dpll pin ref
+ *
+ * Context: shall be called under a lock (dpll_lock)
+ * Return: pointer to the first ops registered with the pin
+ */
+const struct dpll_pin_ops *dpll_pin_ops(struct dpll_pin_ref *ref)
+{
+ struct dpll_pin_registration *reg;
+
+ reg = dpll_pin_registration_first(ref);
+ return reg->ops;
+}
+
+/**
+ * dpll_init - initialize dpll subsystem
+ *
+ * Return:
+ * 0 - success
+ * negative - netlink init error
+ */
+static int __init dpll_init(void)
+{
+ int ret;
+
+ ret = dpll_netlink_init();
+ if (ret)
+ goto error;
+
+ return 0;
+
+error:
+ mutex_destroy(&dpll_lock);
+ return ret;
+}
+subsys_initcall(dpll_init);
new file mode 100644
@@ -0,0 +1,92 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2023 Meta Platforms, Inc. and affiliates
+ * Copyright (c) 2023 Intel and affiliates
+ */
+
+#ifndef __DPLL_CORE_H__
+#define __DPLL_CORE_H__
+
+#include <linux/dpll.h>
+#include <linux/list.h>
+#include <linux/refcount.h>
+#include "dpll_netlink.h"
+
+#define DPLL_REGISTERED XA_MARK_1
+
+/**
+ * struct dpll_device - stores DPLL device internal data
+ * @id: unique id number for device given by dpll subsystem
+ * @device_idx: id given by dev driver
+ * @clock_id: unique identifier (clock_id) of a dpll
+ * @module: module of creator
+ * @type: type of a dpll
+ * @pin_refs: stores pins registered within a dpll
+ * @mode_supported_mask: mask of supported modes
+ * @refcount: refcount
+ * @registration_list: list of registered ops and priv data of dpll owners
+ **/
+struct dpll_device {
+ u32 id;
+ u32 device_idx;
+ u64 clock_id;
+ struct module *module;
+ enum dpll_type type;
+ struct xarray pin_refs;
+ unsigned long mode_supported_mask;
+ refcount_t refcount;
+ struct list_head registration_list;
+};
+
+/**
+ * struct dpll_pin - structure for a dpll pin
+ * @id: unique id number for pin given by dpll subsystem
+ * @pin_idx: index of a pin given by dev driver
+ * @clock_id: clock_id of creator
+ * @module: module of creator
+ * @dpll_refs: hold referencees to dplls pin was registered with
+ * @parent_refs: hold references to parent pins pin was registered with
+ * @prop: pointer to pin properties given by registerer
+ * @rclk_dev_name: holds name of device when pin can recover clock from it
+ * @refcount: refcount
+ **/
+struct dpll_pin {
+ u32 id;
+ u32 pin_idx;
+ u64 clock_id;
+ struct module *module;
+ struct xarray dpll_refs;
+ struct xarray parent_refs;
+ const struct dpll_pin_properties *prop;
+ char *rclk_dev_name;
+ refcount_t refcount;
+};
+
+/**
+ * struct dpll_pin_ref - structure for referencing either dpll or pins
+ * @dpll: pointer to a dpll
+ * @pin: pointer to a pin
+ * @registration_list: list of ops and priv data registered with the ref
+ * @refcount: refcount
+ **/
+struct dpll_pin_ref {
+ union {
+ struct dpll_device *dpll;
+ struct dpll_pin *pin;
+ };
+ struct list_head registration_list;
+ refcount_t refcount;
+};
+
+void *dpll_priv(struct dpll_device *dpll);
+void *dpll_pin_on_dpll_priv(struct dpll_device *dpll, struct dpll_pin *pin);
+void *dpll_pin_on_pin_priv(struct dpll_pin *parent, struct dpll_pin *pin);
+
+const struct dpll_device_ops *dpll_device_ops(struct dpll_device *dpll);
+struct dpll_device *dpll_device_get_by_id(int id);
+const struct dpll_pin_ops *dpll_pin_ops(struct dpll_pin_ref *ref);
+struct dpll_pin_ref *dpll_xa_ref_dpll_first(struct xarray *xa_refs);
+extern struct xarray dpll_device_xa;
+extern struct xarray dpll_pin_xa;
+extern struct mutex dpll_lock;
+#endif