[PATCH v5 net-next 3/8] dpll: extend pin notifier and netlink events with notification source ID

[Grzegorz Nitka <grzegorz.nitka@intel.com>]

Extend the DPLL pin notification API to include a source identifier
indicating where the notification originates. This allows notifier
consumers and netlink listeners to distinguish between notifications
coming from an associated DPLL instance, a parent pin, or the pin
itself.

A new field, src_id, is added to struct dpll_pin_notifier_info and is
passed through all pin-related notification paths. Callers of
dpll_pin_notify() are updated to provide a meaningful source identifier
based on their context:
  - pin registration/unregistration uses the DPLL's clock_id,
  - pin-on-pin operations use the parent pin's clock_id,
  - pin changes use the pin's own clock_id.

As introduced in the commit ("dpll: allow registering FW-identified pin
with a different DPLL"), it is possible to share the same physical pin
via firmware description (fwnode) with DPLL objects from different
kernel modules. This means that a given pin can be registered multiple
times.

Driver such as ICE (E825 devices) rely on this mechanism when listening
for the event where a shared-fwnode pin appears, while avoiding reacting
to events triggered by their own registration logic.

This change only extends the notification metadata and does not alter
existing semantics for drivers that do not use the new field.

Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Grzegorz Nitka <grzegorz.nitka@intel.com>
---
 drivers/dpll/dpll_core.c    | 14 ++++++++------
 drivers/dpll/dpll_core.h    |  3 ++-
 drivers/dpll/dpll_netlink.c | 10 +++++-----
 drivers/dpll/dpll_netlink.h |  4 ++--
 include/linux/dpll.h        |  1 +
 5 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c
index 55ad03977d6d..7d653a29c294 100644
--- a/drivers/dpll/dpll_core.c
+++ b/drivers/dpll/dpll_core.c
@@ -71,7 +71,8 @@ void dpll_device_notify(struct dpll_device *dpll, unsigned long action)
 	call_dpll_notifiers(action, &info);
 }
 
-void dpll_pin_notify(struct dpll_pin *pin, unsigned long action)
+void dpll_pin_notify(struct dpll_pin *pin, u64 src_clock_id,
+		     unsigned long action)
 {
 	struct dpll_pin_notifier_info info = {
 		.pin = pin,
@@ -80,6 +81,7 @@ void dpll_pin_notify(struct dpll_pin *pin, unsigned long action)
 		.clock_id = pin->clock_id,
 		.fwnode = pin->fwnode,
 		.prop = &pin->prop,
+		.src_clock_id = src_clock_id,
 	};
 
 	call_dpll_notifiers(action, &info);
@@ -847,7 +849,7 @@ __dpll_pin_register(struct dpll_device *dpll, struct dpll_pin *pin,
 	if (ret)
 		goto ref_pin_del;
 	xa_set_mark(&dpll_pin_xa, pin->id, DPLL_REGISTERED);
-	dpll_pin_create_ntf(pin);
+	dpll_pin_create_ntf(pin, dpll->clock_id);
 
 	return ret;
 
@@ -946,7 +948,7 @@ void dpll_pin_unregister(struct dpll_device *dpll, struct dpll_pin *pin,
 		return;
 
 	mutex_lock(&dpll_lock);
-	dpll_pin_delete_ntf(pin);
+	dpll_pin_delete_ntf(pin, dpll->clock_id);
 	__dpll_pin_unregister(dpll, pin, ops, priv, NULL);
 	mutex_unlock(&dpll_lock);
 }
@@ -992,7 +994,7 @@ int dpll_pin_on_pin_register(struct dpll_pin *parent, struct dpll_pin *pin,
 			stop = i;
 			goto dpll_unregister;
 		}
-		dpll_pin_create_ntf(pin);
+		dpll_pin_create_ntf(pin, parent->clock_id);
 	}
 	mutex_unlock(&dpll_lock);
 
@@ -1003,7 +1005,7 @@ int dpll_pin_on_pin_register(struct dpll_pin *parent, struct dpll_pin *pin,
 		if (i < stop) {
 			__dpll_pin_unregister(ref->dpll, pin, ops, priv,
 					      parent);
-			dpll_pin_delete_ntf(pin);
+			dpll_pin_delete_ntf(pin, parent->clock_id);
 		}
 	dpll_xa_ref_pin_del(&pin->parent_refs, parent, ops, priv, pin);
 unlock:
@@ -1029,7 +1031,7 @@ void dpll_pin_on_pin_unregister(struct dpll_pin *parent, struct dpll_pin *pin,
 	unsigned long i;
 
 	mutex_lock(&dpll_lock);
-	dpll_pin_delete_ntf(pin);
+	dpll_pin_delete_ntf(pin, parent->clock_id);
 	dpll_xa_ref_pin_del(&pin->parent_refs, parent, ops, priv, pin);
 	xa_for_each(&pin->dpll_refs, i, ref)
 		__dpll_pin_unregister(ref->dpll, pin, ops, priv, parent);
diff --git a/drivers/dpll/dpll_core.h b/drivers/dpll/dpll_core.h
index 71ac88ef2017..92cb919317eb 100644
--- a/drivers/dpll/dpll_core.h
+++ b/drivers/dpll/dpll_core.h
@@ -98,6 +98,7 @@ 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);
+void dpll_pin_notify(struct dpll_pin *pin, u64 src_clock_id,
+		     unsigned long action);
 
 #endif
diff --git a/drivers/dpll/dpll_netlink.c b/drivers/dpll/dpll_netlink.c
index 83cbd64abf5a..5fe6635dd672 100644
--- a/drivers/dpll/dpll_netlink.c
+++ b/drivers/dpll/dpll_netlink.c
@@ -830,21 +830,21 @@ dpll_pin_event_send(enum dpll_cmd event, struct dpll_pin *pin)
 	return ret;
 }
 
-int dpll_pin_create_ntf(struct dpll_pin *pin)
+int dpll_pin_create_ntf(struct dpll_pin *pin, u64 src_clock_id)
 {
-	dpll_pin_notify(pin, DPLL_PIN_CREATED);
+	dpll_pin_notify(pin, src_clock_id, DPLL_PIN_CREATED);
 	return dpll_pin_event_send(DPLL_CMD_PIN_CREATE_NTF, pin);
 }
 
-int dpll_pin_delete_ntf(struct dpll_pin *pin)
+int dpll_pin_delete_ntf(struct dpll_pin *pin,  u64 src_clock_id)
 {
-	dpll_pin_notify(pin, DPLL_PIN_DELETED);
+	dpll_pin_notify(pin, src_clock_id, 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);
+	dpll_pin_notify(pin, pin->clock_id, DPLL_PIN_CHANGED);
 	return dpll_pin_event_send(DPLL_CMD_PIN_CHANGE_NTF, pin);
 }
 
diff --git a/drivers/dpll/dpll_netlink.h b/drivers/dpll/dpll_netlink.h
index dd28b56d27c5..89fef266392f 100644
--- a/drivers/dpll/dpll_netlink.h
+++ b/drivers/dpll/dpll_netlink.h
@@ -8,8 +8,8 @@ int dpll_device_create_ntf(struct dpll_device *dpll);
 
 int dpll_device_delete_ntf(struct dpll_device *dpll);
 
-int dpll_pin_create_ntf(struct dpll_pin *pin);
+int dpll_pin_create_ntf(struct dpll_pin *pin, u64 src_clock_id);
 
-int dpll_pin_delete_ntf(struct dpll_pin *pin);
+int dpll_pin_delete_ntf(struct dpll_pin *pin, u64 src_clock_id);
 
 int __dpll_pin_change_ntf(struct dpll_pin *pin);
diff --git a/include/linux/dpll.h b/include/linux/dpll.h
index 2ce295b46b8c..efa8ef8b6fae 100644
--- a/include/linux/dpll.h
+++ b/include/linux/dpll.h
@@ -202,6 +202,7 @@ struct dpll_pin_notifier_info {
 	u64 clock_id;
 	const struct fwnode_handle *fwnode;
 	const struct dpll_pin_properties *prop;
+	u64 src_clock_id;
 };
 
 #if IS_ENABLED(CONFIG_DPLL)
-- 
2.39.3