>From: Jiri Pirko <jiri@xxxxxxxxxxx>
>Sent: Saturday, June 10, 2023 7:38 PM
>
>Fri, Jun 09, 2023 at 02:18:46PM CEST, arkadiusz.kubalewski@xxxxxxxxx wrote:
>>From: Vadim Fedorenko <vadim.fedorenko@xxxxxxxxx>
>>
>>DPLL framework is used to represent and configure DPLL devices
>>in systems. Each device that has DPLL and can configure inputs
>>and outputs can use this framework.
>>
>>Implement core framework functions for further interactions
>>with device drivers implementing dpll subsystem, as well as for
>>interactions of DPLL netlink framework part with the subsystem
>>itself.
>>
>>Co-developed-by: Milena Olech <milena.olech@xxxxxxxxx>
>>Signed-off-by: Milena Olech <milena.olech@xxxxxxxxx>
>>Co-developed-by: Michal Michalik <michal.michalik@xxxxxxxxx>
>>Signed-off-by: Michal Michalik <michal.michalik@xxxxxxxxx>
>>Signed-off-by: Vadim Fedorenko <vadim.fedorenko@xxxxxxxxx>
>>Co-developed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@xxxxxxxxx>
>>Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@xxxxxxxxx>
>>---
>> drivers/dpll/dpll_core.c | 953 +++++++++++++++++++++++++++++++++++++++
>> drivers/dpll/dpll_core.h | 104 +++++
>
>Overall, looks very good! I pinpointed couple of nits below, nothing big.
>General question: Why do you put documentation comment to every static
>function? Does not make any sense to me. Even for non-exported functions
>I think it is overkill. Most of them (if not all) give the reader no
>additional information and only make the code a bit harder to read.
>Care to drop them?
>
>
>> 2 files changed, 1057 insertions(+)
>> create mode 100644 drivers/dpll/dpll_core.c
>> create mode 100644 drivers/dpll/dpll_core.h
>>
>>diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c
>>new file mode 100644
>>index 000000000000..ee515b7c18be
>>--- /dev/null
>>+++ b/drivers/dpll/dpll_core.c
>>@@ -0,0 +1,953 @@
>>+// SPDX-License-Identifier: GPL-2.0
>>+/*
>>+ * dpll_core.c - Generic DPLL Management class support.
>
>What's "management class support"? Does not sound recognizable.
>
Fixed.
>
>>+ *
>>+ * 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))
>>+
>>+/**
>>+ * 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)
>>+ kfree(ref);
>>+ return -ENOMEM;
>>+ }
>>+ reg->ops = ops;
>>+ reg->priv = priv;
>>+ if (ref_exists)
>
>If you set refcount to 0 couple of lines above, you can drop the check
>here.
>
Fixed.
>
>>+ 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)
>>+ kfree(ref);
>>+ return -ENOMEM;
>>+ }
>>+ reg->ops = ops;
>>+ reg->priv = priv;
>>+ if (ref_exists)
>
>If you set refcount to 0 couple of lines above, you can drop the check
>here.
>
Fixed.
>
>>+ 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)
>>+{
>>+ if (!dpll)
>
>Drop this check and rely on a basic driver sanity. I'm pretty sure I
>asked you to drop checks like this during the last version review.
>
Fixed.
>
>>+ return;
>>+ 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
>>+ */
>>+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(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 -EEXIST;
>
>-ENOMEM;
>
Fixed.
>
>>+ }
>>+ 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 (!pin)
>
>Drop this check.
>
Fixed.
>
>>+ return;
>>+ 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;
>>+
>>+ if (WARN_ON(!ops))
>>+ return -EINVAL;
>>+
>>+ 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;
>>+ else
>>+ 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
>>+ * * -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;
>>+
>>+ mutex_lock(&dpll_lock);
>>+ if (WARN_ON(!(dpll->module == pin->module &&
>>+ dpll->clock_id == pin->clock_id)))
>>+ ret = -EFAULT;
>
>In other cases like this you return -EINVAL. I think it is better. One
>way or another, be consistent please.
>
Fixed.
>
>>+ 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);
>>+}
>>+
>>+/**
>>+ * 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;
>>+ 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);
>>+ }
>
>Drop "{}"s for one line statement. Didn't checkpack warn you?
>
Fixed.
>
>>+ 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);
>>diff --git a/drivers/dpll/dpll_core.h b/drivers/dpll/dpll_core.h
>>new file mode 100644
>>index 000000000000..ef95e272937c
>>--- /dev/null
>>+++ b/drivers/dpll/dpll_core.h
>>@@ -0,0 +1,104 @@
>>+/* 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_registration {
>>+ struct list_head list;
>>+ const struct dpll_device_ops *ops;
>>+ void *priv;
>
>You don't need this struct in the header. Move to .c
>
Fixed.
>
>>+};
>>+
>>+/**
>>+ * struct dpll_device - stores DPLL device internal data
>>+ * @id: unique id number for each device given by kernel
>
>Who's kernel? Say "dpll subsystem" instead.
>
Fixed.
>
>>+ * @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 kernel
>
>Who's kernel? Say "dpll subsystem" instead.
>
Fixed.
>
>>+ * @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_registration {
>>+ struct list_head list;
>>+ const struct dpll_pin_ops *ops;
>>+ void *priv;
>>+};
>
>You don't need this struct in the header. Move to .c
>
Fixed.
Thank you,
Arkadiusz
>
>>+
>>+/**
>>+ * 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
>>--
>>2.37.3
>>
