pds_core: publish events to the clients

When the Core device gets an event from the device, or notices
the device FW to be up or down, it needs to send those events
on to the clients that have an event handler. Add the code to
pass along the events to the clients.

The entry points pdsc_register_notify() and pdsc_unregister_notify()
are EXPORTed for other drivers that want to listen for these events.

Signed-off-by: Shannon Nelson <[e-mail]>
Acked-by: Jakub Kicinski <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/ethernet/amd/pds_core/adminq.c

···
 		case PDS_EVENT_LINK_CHANGE:
 			dev_info(pdsc->dev, "NotifyQ LINK_CHANGE ecode %d eid %lld\n",
 				 ecode, eid);
+			pdsc_notify(PDS_EVENT_LINK_CHANGE, comp);
 			break;
 
 		case PDS_EVENT_RESET:
 			dev_info(pdsc->dev, "NotifyQ RESET ecode %d eid %lld\n",
 				 ecode, eid);
+			pdsc_notify(PDS_EVENT_RESET, comp);
 			break;
 
 		case PDS_EVENT_XCVR:

drivers/net/ethernet/amd/pds_core/core.c

···
 
 #include "core.h"
 
+static BLOCKING_NOTIFIER_HEAD(pds_notify_chain);
+
+int pdsc_register_notify(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&pds_notify_chain, nb);
+}
+EXPORT_SYMBOL_GPL(pdsc_register_notify);
+
+void pdsc_unregister_notify(struct notifier_block *nb)
+{
+	blocking_notifier_chain_unregister(&pds_notify_chain, nb);
+}
+EXPORT_SYMBOL_GPL(pdsc_unregister_notify);
+
+void pdsc_notify(unsigned long event, void *data)
+{
+	blocking_notifier_call_chain(&pds_notify_chain, event, data);
+}
+
 void pdsc_intr_free(struct pdsc *pdsc, int index)
 {
 	struct pdsc_intr_info *intr_info;
···
 
 static void pdsc_fw_down(struct pdsc *pdsc)
 {
+	union pds_core_notifyq_comp reset_event = {
+		.reset.ecode = cpu_to_le16(PDS_EVENT_RESET),
+		.reset.state = 0,
+	};
+
 	if (test_and_set_bit(PDSC_S_FW_DEAD, &pdsc->state)) {
 		dev_err(pdsc->dev, "%s: already happening\n", __func__);
 		return;
 	}
 
+	/* Notify clients of fw_down */
 	devlink_health_report(pdsc->fw_reporter, "FW down reported", pdsc);
+	pdsc_notify(PDS_EVENT_RESET, &reset_event);
 
 	pdsc_stop(pdsc);
 	pdsc_teardown(pdsc, PDSC_TEARDOWN_RECOVERY);
···
 
 static void pdsc_fw_up(struct pdsc *pdsc)
 {
+	union pds_core_notifyq_comp reset_event = {
+		.reset.ecode = cpu_to_le16(PDS_EVENT_RESET),
+		.reset.state = 1,
+	};
 	int err;
 
 	if (!test_bit(PDSC_S_FW_DEAD, &pdsc->state)) {
···
 	if (err)
 		goto err_out;
 
+	/* Notify clients of fw_up */
 	pdsc->fw_recoveries++;
 	devlink_health_reporter_state_update(pdsc->fw_reporter,
 					     DEVLINK_HEALTH_REPORTER_STATE_HEALTHY);
+	pdsc_notify(PDS_EVENT_RESET, &reset_event);
 
 	return;
 

drivers/net/ethernet/amd/pds_core/core.h

···
 void pdsc_stop(struct pdsc *pdsc);
 void pdsc_health_thread(struct work_struct *work);
 
+int pdsc_register_notify(struct notifier_block *nb);
+void pdsc_unregister_notify(struct notifier_block *nb);
+void pdsc_notify(unsigned long event, void *data);
 int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf);
 int pdsc_auxbus_dev_del(struct pdsc *cf, struct pdsc *pf);
 

include/linux/pds/pds_common.h

···
 	PDS_CORE_QTYPE_MAX     = 16   /* don't change - used in struct size */
 };
 
+int pdsc_register_notify(struct notifier_block *nb);
+void pdsc_unregister_notify(struct notifier_block *nb);
 void *pdsc_get_pf_struct(struct pci_dev *vf_pdev);
 int pds_client_register(struct pci_dev *pf_pdev, char *devname);
 int pds_client_unregister(struct pci_dev *pf_pdev, u16 client_id);