*         - SCMI_XFER_SENT_OK -> SCMI_XFER_DRESP_OK
  *           (Missing synchronous response is assumed OK and ignored)
  * @lock: A spinlock to protect state and busy fields.
+ * @priv: A pointer for transport private usage.
  */
 struct scmi_xfer {
        int transfer_id;
        int state;
        /* A lock to protect state and busy fields */
        spinlock_t lock;
+       void *priv;
 };
 
 /*
 extern const struct scmi_desc scmi_smc_desc;
 #endif
 
-void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr);
+void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv);
 void scmi_free_channel(struct scmi_chan_info *cinfo, struct idr *idr, int id);
 
 /* shmem related declarations */
 
                info->desc->ops->clear_channel(cinfo);
 }
 
-static void scmi_handle_notification(struct scmi_chan_info *cinfo, u32 msg_hdr)
+static void scmi_handle_notification(struct scmi_chan_info *cinfo,
+                                    u32 msg_hdr, void *priv)
 {
        struct scmi_xfer *xfer;
        struct device *dev = cinfo->dev;
        }
 
        unpack_scmi_header(msg_hdr, &xfer->hdr);
+       if (priv)
+               xfer->priv = priv;
        info->desc->ops->fetch_notification(cinfo, info->desc->max_msg_size,
                                            xfer);
        scmi_notify(cinfo->handle, xfer->hdr.protocol_id,
        scmi_clear_channel(info, cinfo);
 }
 
-static void scmi_handle_response(struct scmi_chan_info *cinfo, u32 msg_hdr)
+static void scmi_handle_response(struct scmi_chan_info *cinfo,
+                                u32 msg_hdr, void *priv)
 {
        struct scmi_xfer *xfer;
        struct scmi_info *info = handle_to_scmi_info(cinfo->handle);
        if (xfer->hdr.type == MSG_TYPE_DELAYED_RESP)
                xfer->rx.len = info->desc->max_msg_size;
 
+       if (priv)
+               xfer->priv = priv;
        info->desc->ops->fetch_response(cinfo, xfer);
 
        trace_scmi_rx_done(xfer->transfer_id, xfer->hdr.id,
  *
  * @cinfo: SCMI channel info
  * @msg_hdr: Message header
+ * @priv: Transport specific private data.
  *
  * Processes one received message to appropriate transfer information and
  * signals completion of the transfer.
  * NOTE: This function will be invoked in IRQ context, hence should be
  * as optimal as possible.
  */
-void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr)
+void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv)
 {
        u8 msg_type = MSG_XTRACT_TYPE(msg_hdr);
 
        switch (msg_type) {
        case MSG_TYPE_NOTIFICATION:
-               scmi_handle_notification(cinfo, msg_hdr);
+               scmi_handle_notification(cinfo, msg_hdr, priv);
                break;
        case MSG_TYPE_COMMAND:
        case MSG_TYPE_DELAYED_RESP:
-               scmi_handle_response(cinfo, msg_hdr);
+               scmi_handle_response(cinfo, msg_hdr, priv);
                break;
        default:
                WARN_ONCE(1, "received unknown msg_type:%d\n", msg_type);