[PATCH v7 18/23] firmware: arm_scmi: Expose per-instance identifier

When multiple SCMI instances are configured, the SCMI stack probes and
it is initialized multiple times: one core stack for each defined instance.

Each istance is simply identified internally with a number and such number
is already exposed to the user to name the root of the per-instance debugfs
subtree, if enabled.

Expose such unique identifier to the SCMI drivers so that they can use
that same identifier when in need to name their per-instance resources.

Signed-off-by: Cristian Marussi <[email protected]>
---
 drivers/firmware/arm_scmi/driver.c | 1 +
 include/linux/scmi_protocol.h      | 5 +++++
 2 files changed, 6 insertions(+)

diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index d209b3ca0174..87489bc075c2 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -3337,6 +3337,7 @@ static int scmi_probe(struct platform_device *pdev)
 	idr_init(&info->rx_idr);
 
 	handle = &info->handle;
+	handle->id = info->id;
 	handle->dev = info->dev;
 	handle->version = &info->version;
 	handle->devm_protocol_acquire = scmi_devm_protocol_acquire;
diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index 5ca8513385a3..198768752168 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -1127,6 +1127,10 @@ struct scmi_notify_ops {
 /**
  * struct scmi_handle - Handle returned to ARM SCMI clients for usage.
  *
+ * @id: A unique positive natural integer identifying the SCMI Instance
+ *	associated with this handle to be used across all drivers for
+ *	naming purposes: same identifier used internally as the root for
+ *	the debugfs per-instance tree.
  * @dev: pointer to the SCMI device
  * @version: pointer to the structure containing SCMI version information
  * @devm_protocol_acquire: devres managed method to get hold of a protocol,
@@ -1147,6 +1151,7 @@ struct scmi_notify_ops {
  * @notify_ops: pointer to set of notifications related operations
  */
 struct scmi_handle {
+	unsigned int id;
 	struct device *dev;
 	struct scmi_base_info *version;
 
-- 
2.54.0