rpmsg: qcom_smd: Improve error handling for qcom_smd_parse_edge

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.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Luca Weiss <luca@lucaweiss.eu>
Link: https://lore.kernel.org/r/20250326-apcs-mboxes-v3-1-e20f39e125f2@lucaweiss.eu
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

diff --git a/drivers/rpmsg/qcom_smd.c b/drivers/rpmsg/qcom_smd.c
index 40d3868..9b5fa9d 100644 (file)
--- 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) {