dpll: export __dpll_pin_change_ntf() for use under dpll_lock

Export __dpll_pin_change_ntf() so that drivers can send pin change
notifications from within pin callbacks, which are already called
under dpll_lock. Using dpll_pin_change_ntf() in that context would
deadlock.

Add lockdep_assert_held() to catch misuse without the lock held.

Acked-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: Petr Oros <poros@redhat.com>
Tested-by: Alexander Nowlin <alexander.nowlin@intel.com>
Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20260427-jk-iwl-net-petr-oros-fixes-v1-9-cdcb48303fd8@intel.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: ivecera

drivers/dpll/dpll_netlink.c

@@ -900,11 +900,21 @@ int dpll_pin_delete_ntf(struct dpll_pin *pin)
 	return dpll_pin_event_send(DPLL_CMD_PIN_DELETE_NTF, pin);
 }
 
+/**
+ * __dpll_pin_change_ntf - notify that the pin has been changed
+ * @pin: registered pin pointer
+ *
+ * Context: caller must hold dpll_lock. Suitable for use inside pin
+ *          callbacks which are already invoked under dpll_lock.
+ * Return: 0 if succeeds, error code otherwise.
+ */
 int __dpll_pin_change_ntf(struct dpll_pin *pin)
 {
+	lockdep_assert_held(&dpll_lock);
 	dpll_pin_notify(pin, DPLL_PIN_CHANGED);
 	return dpll_pin_event_send(DPLL_CMD_PIN_CHANGE_NTF, pin);
 }
+EXPORT_SYMBOL_GPL(__dpll_pin_change_ntf);
 
 /**
  * dpll_pin_change_ntf - notify that the pin has been changed

drivers/dpll/dpll_netlink.h

@@ -11,5 +11,3 @@ int dpll_device_delete_ntf(struct dpll_device *dpll);
 int dpll_pin_create_ntf(struct dpll_pin *pin);
 
 int dpll_pin_delete_ntf(struct dpll_pin *pin);
-
-int __dpll_pin_change_ntf(struct dpll_pin *pin);

include/linux/dpll.h

@@ -286,6 +286,7 @@ int dpll_pin_ref_sync_pair_add(struct dpll_pin *pin,
 
 int dpll_device_change_ntf(struct dpll_device *dpll);
 
+int __dpll_pin_change_ntf(struct dpll_pin *pin);
 int dpll_pin_change_ntf(struct dpll_pin *pin);
 
 int register_dpll_notifier(struct notifier_block *nb);