[PATCH v2] rpmsg: qcom_smd: Improve error handling for qcom_smd_parse_edge

[Luca Weiss]

When the mailbox driver has not probed yet, the error message "failed to
parse smd edge" is just going to confuse users, so improve the error
prints a bit.

Cover the last remaining exits from qcom_smd_parse_edge with proper
error prints, especially the one for the mbox_chan deserved
dev_err_probe to handle EPROBE_DEFER nicely. And add one for ipc_regmap
also to be complete.

With this done, we can remove the outer print completely.

Signed-off-by: Luca Weiss <luca@xxxxxxxxx>
---
Changes in v2:
- Rebase on qcom for-next, drop dts patches which have been applied
- Improve error printing situation (Bjorn)
- Link to v1: https://lore.kernel.org/r/20240424-apcs-mboxes-v1-0-6556c47cb501@xxxxxxxxx
---
 drivers/rpmsg/qcom_smd.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/rpmsg/qcom_smd.c b/drivers/rpmsg/qcom_smd.c
index 43f601c84b4f..06e6ba653ea1 100644
--- a/drivers/rpmsg/qcom_smd.c
+++ b/drivers/rpmsg/qcom_smd.c
@@ -1369,7 +1369,8 @@ static int qcom_smd_parse_edge(struct device *dev,
 	edge->mbox_chan = mbox_request_channel(&edge->mbox_client, 0);
 	if (IS_ERR(edge->mbox_chan)) {
 		if (PTR_ERR(edge->mbox_chan) != -ENODEV) {
-			ret = PTR_ERR(edge->mbox_chan);
+			ret = dev_err_probe(dev, PTR_ERR(edge->mbox_chan),
+					    "failed to acquire IPC mailbox\n");
 			goto put_node;
 		}
 
@@ -1386,6 +1387,7 @@ static int qcom_smd_parse_edge(struct device *dev,
 		of_node_put(syscon_np);
 		if (IS_ERR(edge->ipc_regmap)) {
 			ret = PTR_ERR(edge->ipc_regmap);
+			dev_err(dev, "failed to get regmap from syscon: %d\n", ret);
 			goto put_node;
 		}
 
@@ -1501,10 +1503,8 @@ struct qcom_smd_edge *qcom_smd_register_edge(struct device *parent,
 	}
 
 	ret = qcom_smd_parse_edge(&edge->dev, node, edge);
-	if (ret) {
-		dev_err(&edge->dev, "failed to parse smd edge\n");
+	if (ret)
 		goto unregister_dev;
-	}
 
 	ret = qcom_smd_create_chrdev(edge);
 	if (ret) {

---
base-commit: 2c79712cc83b172ce26c3086ced1c1fae087d8fb
change-id: 20240423-apcs-mboxes-12ee6c01a5b3

Best regards,
-- 
Luca Weiss <luca@xxxxxxxxx>