Add support for Telemetry operations needed to request platform to
reset telemetry current configuration and data events values.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
v2 --> v3
 - split from monolithic Telemetry patch
 - use scmi_telemetry_de_unlink
---
 drivers/firmware/arm_scmi/telemetry.c | 44 +++++++++++++++++++++++++++
 include/linux/scmi_protocol.h         |  2 ++
 2 files changed, 46 insertions(+)

diff --git a/drivers/firmware/arm_scmi/telemetry.c b/drivers/firmware/arm_scmi/telemetry.c
index 61eaad817db4..ff0a5a8f6f57 100644
--- a/drivers/firmware/arm_scmi/telemetry.c
+++ b/drivers/firmware/arm_scmi/telemetry.c
@@ -2456,6 +2456,49 @@ static int scmi_telemetry_des_sample_get(const struct scmi_protocol_handle *ph,
 	return ret;
 }
 
+static void scmi_telemetry_local_resources_reset(struct telemetry_info *ti)
+{
+	struct scmi_telemetry_res_info *rinfo;
+
+	/* Get rinfo as it is...without triggering an enumeration */
+	rinfo = __scmi_telemetry_resources_get(ti);
+	/* Clear all local state...*/
+	for (int i = 0; i < rinfo->num_des; i++) {
+		rinfo->des[i]->enabled = false;
+		rinfo->des[i]->tstamp_enabled = false;
+
+		scmi_telemetry_de_unlink(rinfo->des[i]);
+	}
+	for (int i = 0; i < rinfo->num_groups; i++) {
+		rinfo->grps[i].enabled = false;
+		rinfo->grps[i].tstamp_enabled = false;
+		rinfo->grps[i].current_mode = SCMI_TLM_ONDEMAND;
+		rinfo->grps[i].active_update_interval = 0;
+	}
+}
+
+static int scmi_telemetry_reset(const struct scmi_protocol_handle *ph)
+{
+	struct scmi_xfer *t;
+	int ret;
+
+	ret = ph->xops->xfer_get_init(ph, TELEMETRY_RESET, sizeof(u32), 0, &t);
+	if (ret)
+		return ret;
+
+	put_unaligned_le32(0, t->tx.buf);
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret) {
+		struct telemetry_info *ti = ph->get_priv(ph);
+
+		scmi_telemetry_local_resources_reset(ti);
+	}
+
+	ph->xops->xfer_put(ph, t);
+
+	return ret;
+}
+
 static const struct scmi_telemetry_proto_ops tlm_proto_ops = {
 	.info_get = scmi_telemetry_info_get,
 	.de_lookup = scmi_telemetry_de_lookup,
@@ -2467,6 +2510,7 @@ static const struct scmi_telemetry_proto_ops tlm_proto_ops = {
 	.de_data_read = scmi_telemetry_de_data_read,
 	.des_bulk_read = scmi_telemetry_des_bulk_read,
 	.des_sample_get = scmi_telemetry_des_sample_get,
+	.reset = scmi_telemetry_reset,
 };
 
 /**
diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index 5f05df297064..fc3b5493dc1a 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -963,6 +963,7 @@ struct scmi_telemetry_de_sample {
  *		    the ones belonging to a specific group when provided.
  *		    This causes an immediate update platform-side of all the
  *		    enabled DEs.
+ * @reset: reset configuration and telemetry data.
  */
 struct scmi_telemetry_proto_ops {
 	const struct scmi_telemetry_info __must_check *(*info_get)
@@ -989,6 +990,7 @@ struct scmi_telemetry_proto_ops {
 	int __must_check (*des_sample_get)(const struct scmi_protocol_handle *ph,
 					   int grp_id, int *num_samples,
 					   struct scmi_telemetry_de_sample *samples);
+	int (*reset)(const struct scmi_protocol_handle *ph);
 };
 
 /**
-- 
2.53.0