1 files changed, 59 insertions, 0 deletions
diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index 93383154d2c1..e90ab458b08e 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -149,6 +149,65 @@ int scmi_xfer_get_init(const struct scmi_handle *h, u8 msg_id, u8 prot_id,
 		       size_t tx_size, size_t rx_size, struct scmi_xfer **p);
 void scmi_reset_rx_to_maxsz(const struct scmi_handle *handle,
 			    struct scmi_xfer *xfer);
+
+struct scmi_xfer_ops;
+
+/**
+ * struct scmi_protocol_handle  - Reference to an initialized protocol instance
+ *
+ * @dev: A reference to the associated SCMI instance device (handle->dev).
+ * @xops: A reference to a struct holding refs to the core xfer operations that
+ *	  can be used by the protocol implementation to generate SCMI messages.
+ * @set_priv: A method to set protocol private data for this instance.
+ * @get_priv: A method to get protocol private data previously set.
+ *
+ * This structure represents a protocol initialized against specific SCMI
+ * instance and it will be used as follows:
+ * - as a parameter fed from the core to the protocol initialization code so
+ *   that it can access the core xfer operations to build and generate SCMI
+ *   messages exclusively for the specific underlying protocol instance.
+ * - as an opaque handle fed by an SCMI driver user when it tries to access
+ *   this protocol through its own protocol operations.
+ *   In this case this handle will be returned as an opaque object together
+ *   with the related protocol operations when the SCMI driver tries to access
+ *   the protocol.
+ */
+struct scmi_protocol_handle {
+	struct device *dev;
+	const struct scmi_xfer_ops *xops;
+	int (*set_priv)(const struct scmi_protocol_handle *ph, void *priv);
+	void *(*get_priv)(const struct scmi_protocol_handle *ph);
+};
+
+/**
+ * struct scmi_xfer_ops  - References to the core SCMI xfer operations.
+ * @version_get: Get this version protocol.
+ * @xfer_get_init: Initialize one struct xfer if any xfer slot is free.
+ * @reset_rx_to_maxsz: Reset rx size to max transport size.
+ * @do_xfer: Do the SCMI transfer.
+ * @do_xfer_with_response: Do the SCMI transfer waiting for a response.
+ * @xfer_put: Free the xfer slot.
+ *
+ * Note that all this operations expect a protocol handle as first parameter;
+ * they then internally use it to infer the underlying protocol number: this
+ * way is not possible for a protocol implementation to forge messages for
+ * another protocol.
+ */
+struct scmi_xfer_ops {
+	int (*version_get)(const struct scmi_protocol_handle *ph, u32 *version);
+	int (*xfer_get_init)(const struct scmi_protocol_handle *ph, u8 msg_id,
+			     size_t tx_size, size_t rx_size,
+			     struct scmi_xfer **p);
+	void (*reset_rx_to_maxsz)(const struct scmi_protocol_handle *ph,
+				  struct scmi_xfer *xfer);
+	int (*do_xfer)(const struct scmi_protocol_handle *ph,
+		       struct scmi_xfer *xfer);
+	int (*do_xfer_with_response)(const struct scmi_protocol_handle *ph,
+				     struct scmi_xfer *xfer);
+	void (*xfer_put)(const struct scmi_protocol_handle *ph,
+			 struct scmi_xfer *xfer);
+};
+
 int scmi_handle_put(const struct scmi_handle *handle);
 struct scmi_handle *scmi_handle_get(struct device *dev);
 void scmi_set_handle(struct scmi_device *scmi_dev);