firmware: arm_scmi: Implement is_notify_supported callback in sensor protocol

Add a preliminary check to verify if the sensor protocol related notify
enable commands are supported at all by the SCMI platform, and then
provide the callback needed to allow the core SCMI notification
subsytem to do a fine-grain check if a specific resource domain
supports notifications.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20240212123233.1230090-8-cristian.marussi@arm.comSigned-off-by: Sudeep Holla <sudeep.holla@arm.com>

drivers/firmware/arm_scmi/sensors.c

@@ -215,6 +215,8 @@ struct scmi_sensor_update_notify_payld {
 
 struct sensors_info {
 	u32 version;
+	bool notify_trip_point_cmd;
+	bool notify_continuos_update_cmd;
 	int num_sensors;
 	int max_requests;
 	u64 reg_addr;
@@ -246,6 +248,18 @@ static int scmi_sensor_attributes_get(const struct scmi_protocol_handle *ph,
 	}
 
 	ph->xops->xfer_put(ph, t);
+
+	if (!ret) {
+		if (!ph->hops->protocol_msg_check(ph,
+						  SENSOR_TRIP_POINT_NOTIFY, NULL))
+			si->notify_trip_point_cmd = true;
+
+		if (!ph->hops->protocol_msg_check(ph,
+						  SENSOR_CONTINUOUS_UPDATE_NOTIFY,
+						  NULL))
+			si->notify_continuos_update_cmd = true;
+	}
+
 	return ret;
 }
 
@@ -594,7 +608,8 @@ iter_sens_descr_process_response(const struct scmi_protocol_handle *ph,
 	 * Such bitfields are assumed to be zeroed on non
 	 * relevant fw versions...assuming fw not buggy !
 	 */
-	s->update = SUPPORTS_UPDATE_NOTIFY(attrl);
+	if (si->notify_continuos_update_cmd)
+		s->update = SUPPORTS_UPDATE_NOTIFY(attrl);
 	s->timestamped = SUPPORTS_TIMESTAMP(attrl);
 	if (s->timestamped)
 		s->tstamp_scale = S32_EXT(SENSOR_TSTAMP_EXP(attrl));
@@ -988,6 +1003,25 @@ static const struct scmi_sensor_proto_ops sensor_proto_ops = {
 	.config_set = scmi_sensor_config_set,
 };
 
+static bool scmi_sensor_notify_supported(const struct scmi_protocol_handle *ph,
+					 u8 evt_id, u32 src_id)
+{
+	bool supported = false;
+	const struct scmi_sensor_info *s;
+	struct sensors_info *sinfo = ph->get_priv(ph);
+
+	s = scmi_sensor_info_get(ph, src_id);
+	if (!s)
+		return false;
+
+	if (evt_id == SCMI_EVENT_SENSOR_TRIP_POINT_EVENT)
+		supported = sinfo->notify_trip_point_cmd;
+	else if (evt_id == SCMI_EVENT_SENSOR_UPDATE)
+		supported = s->update;
+
+	return supported;
+}
+
 static int scmi_sensor_set_notify_enabled(const struct scmi_protocol_handle *ph,
 					  u8 evt_id, u32 src_id, bool enable)
 {
@@ -1099,6 +1133,7 @@ static const struct scmi_event sensor_events[] = {
 };
 
 static const struct scmi_event_ops sensor_event_ops = {
+	.is_notify_supported = scmi_sensor_notify_supported,
 	.get_num_sources = scmi_sensor_get_num_sources,
 	.set_notify_enabled = scmi_sensor_set_notify_enabled,
 	.fill_custom_report = scmi_sensor_fill_custom_report,