From: Petr Oros <poros@redhat.com>
Currently, the DPLL subsystem reports events (creation, deletion, changes)
to userspace via Netlink. However, there is no mechanism for other kernel
components to be notified of these events directly.
Add a raw notifier chain to the DPLL core protected by dpll_lock. This
allows other kernel subsystems or drivers to register callbacks and
receive notifications when DPLL devices or pins are created, deleted,
or modified.
Define the following:
- Registration helpers: {,un}register_dpll_notifier()
- Event types: DPLL_DEVICE_CREATED, DPLL_PIN_CREATED, etc.
- Context structures: dpll_{device,pin}_notifier_info to pass relevant
data to the listeners.
The notification chain is invoked alongside the existing Netlink event
generation to ensure in-kernel listeners are kept in sync with the
subsystem state.
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Co-developed-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: Petr Oros <poros@redhat.com>
---
drivers/dpll/dpll_core.c | 57 +++++++++++++++++++++++++++++++++++++
drivers/dpll/dpll_core.h | 4 +++
drivers/dpll/dpll_netlink.c | 6 ++++
include/linux/dpll.h | 29 +++++++++++++++++++
4 files changed, 96 insertions(+)
diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c
index f04ed7195cadd..b05fe2ba46d91 100644
--- a/drivers/dpll/dpll_core.c
+++ b/drivers/dpll/dpll_core.c
@@ -23,6 +23,8 @@ DEFINE_MUTEX(dpll_lock);
DEFINE_XARRAY_FLAGS(dpll_device_xa, XA_FLAGS_ALLOC);
DEFINE_XARRAY_FLAGS(dpll_pin_xa, XA_FLAGS_ALLOC);
+static RAW_NOTIFIER_HEAD(dpll_notifier_chain);
+
static u32 dpll_device_xa_id;
static u32 dpll_pin_xa_id;
@@ -46,6 +48,39 @@ struct dpll_pin_registration {
void *cookie;
};
+static int call_dpll_notifiers(unsigned long action, void *info)
+{
+ lockdep_assert_held(&dpll_lock);
+ return raw_notifier_call_chain(&dpll_notifier_chain, action, info);
+}
+
+void dpll_device_notify(struct dpll_device *dpll, unsigned long action)
+{
+ struct dpll_device_notifier_info info = {
+ .dpll = dpll,
+ .id = dpll->id,
+ .idx = dpll->device_idx,
+ .clock_id = dpll->clock_id,
+ .type = dpll->type,
+ };
+
+ call_dpll_notifiers(action, &info);
+}
+
+void dpll_pin_notify(struct dpll_pin *pin, unsigned long action)
+{
+ struct dpll_pin_notifier_info info = {
+ .pin = pin,
+ .id = pin->id,
+ .idx = pin->pin_idx,
+ .clock_id = pin->clock_id,
+ .fwnode = pin->fwnode,
+ .prop = &pin->prop,
+ };
+
+ call_dpll_notifiers(action, &info);
+}
+
struct dpll_device *dpll_device_get_by_id(int id)
{
if (xa_get_mark(&dpll_device_xa, id, DPLL_REGISTERED))
@@ -539,6 +574,28 @@ void dpll_netdev_pin_clear(struct net_device *dev)
}
EXPORT_SYMBOL(dpll_netdev_pin_clear);
+int register_dpll_notifier(struct notifier_block *nb)
+{
+ int ret;
+
+ mutex_lock(&dpll_lock);
+ ret = raw_notifier_chain_register(&dpll_notifier_chain, nb);
+ mutex_unlock(&dpll_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(register_dpll_notifier);
+
+int unregister_dpll_notifier(struct notifier_block *nb)
+{
+ int ret;
+
+ mutex_lock(&dpll_lock);
+ ret = raw_notifier_chain_unregister(&dpll_notifier_chain, nb);
+ mutex_unlock(&dpll_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(unregister_dpll_notifier);
+
/**
* dpll_pin_get - find existing or create new dpll pin
* @clock_id: clock_id of creator
diff --git a/drivers/dpll/dpll_core.h b/drivers/dpll/dpll_core.h
index d3e17ff0ecef0..b7b4bb251f739 100644
--- a/drivers/dpll/dpll_core.h
+++ b/drivers/dpll/dpll_core.h
@@ -91,4 +91,8 @@ 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;
+
+void dpll_device_notify(struct dpll_device *dpll, unsigned long action);
+void dpll_pin_notify(struct dpll_pin *pin, unsigned long action);
+
#endif
diff --git a/drivers/dpll/dpll_netlink.c b/drivers/dpll/dpll_netlink.c
index 904199ddd1781..83cbd64abf5a4 100644
--- a/drivers/dpll/dpll_netlink.c
+++ b/drivers/dpll/dpll_netlink.c
@@ -761,17 +761,20 @@ dpll_device_event_send(enum dpll_cmd event, struct dpll_device *dpll)
int dpll_device_create_ntf(struct dpll_device *dpll)
{
+ dpll_device_notify(dpll, DPLL_DEVICE_CREATED);
return dpll_device_event_send(DPLL_CMD_DEVICE_CREATE_NTF, dpll);
}
int dpll_device_delete_ntf(struct dpll_device *dpll)
{
+ dpll_device_notify(dpll, DPLL_DEVICE_DELETED);
return dpll_device_event_send(DPLL_CMD_DEVICE_DELETE_NTF, dpll);
}
static int
__dpll_device_change_ntf(struct dpll_device *dpll)
{
+ dpll_device_notify(dpll, DPLL_DEVICE_CHANGED);
return dpll_device_event_send(DPLL_CMD_DEVICE_CHANGE_NTF, dpll);
}
@@ -829,16 +832,19 @@ dpll_pin_event_send(enum dpll_cmd event, struct dpll_pin *pin)
int dpll_pin_create_ntf(struct dpll_pin *pin)
{
+ dpll_pin_notify(pin, DPLL_PIN_CREATED);
return dpll_pin_event_send(DPLL_CMD_PIN_CREATE_NTF, pin);
}
int dpll_pin_delete_ntf(struct dpll_pin *pin)
{
+ dpll_pin_notify(pin, DPLL_PIN_DELETED);
return dpll_pin_event_send(DPLL_CMD_PIN_DELETE_NTF, pin);
}
int __dpll_pin_change_ntf(struct dpll_pin *pin)
{
+ dpll_pin_notify(pin, DPLL_PIN_CHANGED);
return dpll_pin_event_send(DPLL_CMD_PIN_CHANGE_NTF, pin);
}
diff --git a/include/linux/dpll.h b/include/linux/dpll.h
index f2e8660e90cdf..8ed90dfc65f05 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/notifier.h>
#include <linux/rtnetlink.h>
struct dpll_device;
@@ -172,6 +173,30 @@ struct dpll_pin_properties {
u32 phase_gran;
};
+#define DPLL_DEVICE_CREATED 1
+#define DPLL_DEVICE_DELETED 2
+#define DPLL_DEVICE_CHANGED 3
+#define DPLL_PIN_CREATED 4
+#define DPLL_PIN_DELETED 5
+#define DPLL_PIN_CHANGED 6
+
+struct dpll_device_notifier_info {
+ struct dpll_device *dpll;
+ u32 id;
+ u32 idx;
+ u64 clock_id;
+ enum dpll_type type;
+};
+
+struct dpll_pin_notifier_info {
+ struct dpll_pin *pin;
+ u32 id;
+ u32 idx;
+ u64 clock_id;
+ const struct fwnode_handle *fwnode;
+ const struct dpll_pin_properties *prop;
+};
+
#if IS_ENABLED(CONFIG_DPLL)
void dpll_netdev_pin_set(struct net_device *dev, struct dpll_pin *dpll_pin);
void dpll_netdev_pin_clear(struct net_device *dev);
@@ -242,4 +267,8 @@ int dpll_device_change_ntf(struct dpll_device *dpll);
int dpll_pin_change_ntf(struct dpll_pin *pin);
+int register_dpll_notifier(struct notifier_block *nb);
+
+int unregister_dpll_notifier(struct notifier_block *nb);
+
#endif
--
2.52.0
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf
> Of Ivan Vecera
> Sent: Tuesday, February 3, 2026 6:40 PM
> To: netdev@vger.kernel.org
> Cc: Eric Dumazet <edumazet@google.com>; Nguyen, Anthony L
> <anthony.l.nguyen@intel.com>; Leon Romanovsky <leon@kernel.org>;
> Lobakin, Aleksander <aleksander.lobakin@intel.com>; linux-
> rdma@vger.kernel.org; Kitszel, Przemyslaw
> <przemyslaw.kitszel@intel.com>; Kubalewski, Arkadiusz
> <arkadiusz.kubalewski@intel.com>; intel-wired-lan@lists.osuosl.org;
> Jakub Kicinski <kuba@kernel.org>; Paolo Abeni <pabeni@redhat.com>;
> Jiri Pirko <jiri@resnulli.us>; Richard Cochran
> <richardcochran@gmail.com>; Prathosh Satish
> <Prathosh.Satish@microchip.com>; Vadim Fedorenko
> <vadim.fedorenko@linux.dev>; Mark Bloch <mbloch@nvidia.com>; linux-
> kernel@vger.kernel.org; Tariq Toukan <tariqt@nvidia.com>; Andrew Lunn
> <andrew+netdev@lunn.ch>; Jonathan Lemon <jonathan.lemon@gmail.com>;
> Saeed Mahameed <saeedm@nvidia.com>; David S. Miller
> <davem@davemloft.net>
> Subject: [Intel-wired-lan] [PATCH net-next v5 3/9] dpll: Add notifier
> chain for dpll events
>
> From: Petr Oros <poros@redhat.com>
>
> Currently, the DPLL subsystem reports events (creation, deletion,
> changes) to userspace via Netlink. However, there is no mechanism for
> other kernel components to be notified of these events directly.
>
> Add a raw notifier chain to the DPLL core protected by dpll_lock. This
> allows other kernel subsystems or drivers to register callbacks and
> receive notifications when DPLL devices or pins are created, deleted,
> or modified.
>
> Define the following:
> - Registration helpers: {,un}register_dpll_notifier()
> - Event types: DPLL_DEVICE_CREATED, DPLL_PIN_CREATED, etc.
> - Context structures: dpll_{device,pin}_notifier_info to pass
> relevant
> data to the listeners.
>
> The notification chain is invoked alongside the existing Netlink event
> generation to ensure in-kernel listeners are kept in sync with the
> subsystem state.
>
> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
> Co-developed-by: Ivan Vecera <ivecera@redhat.com>
> Signed-off-by: Ivan Vecera <ivecera@redhat.com>
> Signed-off-by: Petr Oros <poros@redhat.com>
> ---
> drivers/dpll/dpll_core.c | 57
> +++++++++++++++++++++++++++++++++++++
> drivers/dpll/dpll_core.h | 4 +++
> drivers/dpll/dpll_netlink.c | 6 ++++
> include/linux/dpll.h | 29 +++++++++++++++++++
> 4 files changed, 96 insertions(+)
>
> diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c index
> f04ed7195cadd..b05fe2ba46d91 100644
> --- a/drivers/dpll/dpll_core.c
> +++ b/drivers/dpll/dpll_core.c
> @@ -23,6 +23,8 @@ DEFINE_MUTEX(dpll_lock);
> DEFINE_XARRAY_FLAGS(dpll_device_xa, XA_FLAGS_ALLOC);
> DEFINE_XARRAY_FLAGS(dpll_pin_xa, XA_FLAGS_ALLOC);
>
> +static RAW_NOTIFIER_HEAD(dpll_notifier_chain);
> +
...
> --
> 2.52.0
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
>From: Ivan Vecera <ivecera@redhat.com>
>Sent: Tuesday, February 3, 2026 6:40 PM
>
>From: Petr Oros <poros@redhat.com>
>
>Currently, the DPLL subsystem reports events (creation, deletion, changes)
>to userspace via Netlink. However, there is no mechanism for other kernel
>components to be notified of these events directly.
>
>Add a raw notifier chain to the DPLL core protected by dpll_lock. This
>allows other kernel subsystems or drivers to register callbacks and
>receive notifications when DPLL devices or pins are created, deleted,
>or modified.
>
>Define the following:
>- Registration helpers: {,un}register_dpll_notifier()
>- Event types: DPLL_DEVICE_CREATED, DPLL_PIN_CREATED, etc.
>- Context structures: dpll_{device,pin}_notifier_info to pass relevant
> data to the listeners.
>
>The notification chain is invoked alongside the existing Netlink event
>generation to ensure in-kernel listeners are kept in sync with the
>subsystem state.
>
>Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
LGTM,
Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
>Co-developed-by: Ivan Vecera <ivecera@redhat.com>
>Signed-off-by: Ivan Vecera <ivecera@redhat.com>
>Signed-off-by: Petr Oros <poros@redhat.com>
>---
> drivers/dpll/dpll_core.c | 57 +++++++++++++++++++++++++++++++++++++
> drivers/dpll/dpll_core.h | 4 +++
> drivers/dpll/dpll_netlink.c | 6 ++++
> include/linux/dpll.h | 29 +++++++++++++++++++
> 4 files changed, 96 insertions(+)
>
>diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c
>index f04ed7195cadd..b05fe2ba46d91 100644
>--- a/drivers/dpll/dpll_core.c
>+++ b/drivers/dpll/dpll_core.c
>@@ -23,6 +23,8 @@ DEFINE_MUTEX(dpll_lock);
> DEFINE_XARRAY_FLAGS(dpll_device_xa, XA_FLAGS_ALLOC);
> DEFINE_XARRAY_FLAGS(dpll_pin_xa, XA_FLAGS_ALLOC);
>
>+static RAW_NOTIFIER_HEAD(dpll_notifier_chain);
>+
> static u32 dpll_device_xa_id;
> static u32 dpll_pin_xa_id;
>
>@@ -46,6 +48,39 @@ struct dpll_pin_registration {
> void *cookie;
> };
>
>+static int call_dpll_notifiers(unsigned long action, void *info)
>+{
>+ lockdep_assert_held(&dpll_lock);
>+ return raw_notifier_call_chain(&dpll_notifier_chain, action, info);
>+}
>+
>+void dpll_device_notify(struct dpll_device *dpll, unsigned long action)
>+{
>+ struct dpll_device_notifier_info info = {
>+ .dpll = dpll,
>+ .id = dpll->id,
>+ .idx = dpll->device_idx,
>+ .clock_id = dpll->clock_id,
>+ .type = dpll->type,
>+ };
>+
>+ call_dpll_notifiers(action, &info);
>+}
>+
>+void dpll_pin_notify(struct dpll_pin *pin, unsigned long action)
>+{
>+ struct dpll_pin_notifier_info info = {
>+ .pin = pin,
>+ .id = pin->id,
>+ .idx = pin->pin_idx,
>+ .clock_id = pin->clock_id,
>+ .fwnode = pin->fwnode,
>+ .prop = &pin->prop,
>+ };
>+
>+ call_dpll_notifiers(action, &info);
>+}
>+
> struct dpll_device *dpll_device_get_by_id(int id)
> {
> if (xa_get_mark(&dpll_device_xa, id, DPLL_REGISTERED))
>@@ -539,6 +574,28 @@ void dpll_netdev_pin_clear(struct net_device *dev)
> }
> EXPORT_SYMBOL(dpll_netdev_pin_clear);
>
>+int register_dpll_notifier(struct notifier_block *nb)
>+{
>+ int ret;
>+
>+ mutex_lock(&dpll_lock);
>+ ret = raw_notifier_chain_register(&dpll_notifier_chain, nb);
>+ mutex_unlock(&dpll_lock);
>+ return ret;
>+}
>+EXPORT_SYMBOL_GPL(register_dpll_notifier);
>+
>+int unregister_dpll_notifier(struct notifier_block *nb)
>+{
>+ int ret;
>+
>+ mutex_lock(&dpll_lock);
>+ ret = raw_notifier_chain_unregister(&dpll_notifier_chain, nb);
>+ mutex_unlock(&dpll_lock);
>+ return ret;
>+}
>+EXPORT_SYMBOL_GPL(unregister_dpll_notifier);
>+
> /**
> * dpll_pin_get - find existing or create new dpll pin
> * @clock_id: clock_id of creator
>diff --git a/drivers/dpll/dpll_core.h b/drivers/dpll/dpll_core.h
>index d3e17ff0ecef0..b7b4bb251f739 100644
>--- a/drivers/dpll/dpll_core.h
>+++ b/drivers/dpll/dpll_core.h
>@@ -91,4 +91,8 @@ 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;
>+
>+void dpll_device_notify(struct dpll_device *dpll, unsigned long action);
>+void dpll_pin_notify(struct dpll_pin *pin, unsigned long action);
>+
> #endif
>diff --git a/drivers/dpll/dpll_netlink.c b/drivers/dpll/dpll_netlink.c
>index 904199ddd1781..83cbd64abf5a4 100644
>--- a/drivers/dpll/dpll_netlink.c
>+++ b/drivers/dpll/dpll_netlink.c
>@@ -761,17 +761,20 @@ dpll_device_event_send(enum dpll_cmd event, struct
>dpll_device *dpll)
>
> int dpll_device_create_ntf(struct dpll_device *dpll)
> {
>+ dpll_device_notify(dpll, DPLL_DEVICE_CREATED);
> return dpll_device_event_send(DPLL_CMD_DEVICE_CREATE_NTF, dpll);
> }
>
> int dpll_device_delete_ntf(struct dpll_device *dpll)
> {
>+ dpll_device_notify(dpll, DPLL_DEVICE_DELETED);
> return dpll_device_event_send(DPLL_CMD_DEVICE_DELETE_NTF, dpll);
> }
>
> static int
> __dpll_device_change_ntf(struct dpll_device *dpll)
> {
>+ dpll_device_notify(dpll, DPLL_DEVICE_CHANGED);
> return dpll_device_event_send(DPLL_CMD_DEVICE_CHANGE_NTF, dpll);
> }
>
>@@ -829,16 +832,19 @@ dpll_pin_event_send(enum dpll_cmd event, struct
>dpll_pin *pin)
>
> int dpll_pin_create_ntf(struct dpll_pin *pin)
> {
>+ dpll_pin_notify(pin, DPLL_PIN_CREATED);
> return dpll_pin_event_send(DPLL_CMD_PIN_CREATE_NTF, pin);
> }
>
> int dpll_pin_delete_ntf(struct dpll_pin *pin)
> {
>+ dpll_pin_notify(pin, DPLL_PIN_DELETED);
> return dpll_pin_event_send(DPLL_CMD_PIN_DELETE_NTF, pin);
> }
>
> int __dpll_pin_change_ntf(struct dpll_pin *pin)
> {
>+ dpll_pin_notify(pin, DPLL_PIN_CHANGED);
> return dpll_pin_event_send(DPLL_CMD_PIN_CHANGE_NTF, pin);
> }
>
>diff --git a/include/linux/dpll.h b/include/linux/dpll.h
>index f2e8660e90cdf..8ed90dfc65f05 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/notifier.h>
> #include <linux/rtnetlink.h>
>
> struct dpll_device;
>@@ -172,6 +173,30 @@ struct dpll_pin_properties {
> u32 phase_gran;
> };
>
>+#define DPLL_DEVICE_CREATED 1
>+#define DPLL_DEVICE_DELETED 2
>+#define DPLL_DEVICE_CHANGED 3
>+#define DPLL_PIN_CREATED 4
>+#define DPLL_PIN_DELETED 5
>+#define DPLL_PIN_CHANGED 6
>+
>+struct dpll_device_notifier_info {
>+ struct dpll_device *dpll;
>+ u32 id;
>+ u32 idx;
>+ u64 clock_id;
>+ enum dpll_type type;
>+};
>+
>+struct dpll_pin_notifier_info {
>+ struct dpll_pin *pin;
>+ u32 id;
>+ u32 idx;
>+ u64 clock_id;
>+ const struct fwnode_handle *fwnode;
>+ const struct dpll_pin_properties *prop;
>+};
>+
> #if IS_ENABLED(CONFIG_DPLL)
> void dpll_netdev_pin_set(struct net_device *dev, struct dpll_pin
>*dpll_pin);
> void dpll_netdev_pin_clear(struct net_device *dev);
>@@ -242,4 +267,8 @@ int dpll_device_change_ntf(struct dpll_device *dpll);
>
> int dpll_pin_change_ntf(struct dpll_pin *pin);
>
>+int register_dpll_notifier(struct notifier_block *nb);
>+
>+int unregister_dpll_notifier(struct notifier_block *nb);
>+
> #endif
>--
>2.52.0
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