[RFC PATCH v2 06/10] firmware: arm_scmi: Add optional link_supplier() transport op

[Peter Hilber]

For the scmi-virtio transport, it might not be possible to refer to the
proper virtio device at device tree build time. Therefore, add an op
which will allow scmi-virtio to dynamically link to the proper virtio
device during probe.

Signed-off-by: Peter Hilber <peter.hilber@xxxxxxxxxxxxxxx>
---
 drivers/firmware/arm_scmi/common.h | 2 ++
 drivers/firmware/arm_scmi/driver.c | 6 ++++++
 2 files changed, 8 insertions(+)

diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index ae5db602e45d..2f55ac71555a 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -202,6 +202,7 @@ struct scmi_chan_info {
 /**
  * struct scmi_transport_ops - Structure representing a SCMI transport ops
  *
+ * @link_supplier: Optional callback to add link to a supplier device
  * @chan_available: Callback to check if channel is available or not
  * @chan_setup: Callback to allocate and setup a channel
  * @chan_free: Callback to free a channel
@@ -217,6 +218,7 @@ struct scmi_chan_info {
  * @poll_done: Callback to poll transfer status
  */
 struct scmi_transport_ops {
+	int (*link_supplier)(struct device *dev);
 	bool (*chan_available)(struct device *dev, int idx);
 	int (*chan_setup)(struct scmi_chan_info *cinfo, struct device *dev,
 			  bool tx);
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index d7ad5a77b9dc..dedc9b3f3e97 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -826,6 +826,12 @@ static int scmi_probe(struct platform_device *pdev)
 	handle->dev = info->dev;
 	handle->version = &info->version;
 
+	if (desc->ops->link_supplier) {
+		ret = desc->ops->link_supplier(dev);
+		if (ret)
+			return ret;
+	}
+
 	ret = scmi_txrx_setup(info, dev, SCMI_PROTOCOL_BASE);
 	if (ret)
 		return ret;
-- 
2.25.1