lib: devres: Add error information printing for __devm_ioremap_resource()

Ensure that all error handling branches print error information. In this
way, when this function fails, the upper-layer functions can directly
return an error code without missing debugging information. Otherwise,
the error message will be printed redundantly or missing.

Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Link: https://lore.kernel.org/r/20210428063203.691-1-thunder.leizhen@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/lib/devres.c b/lib/devres.c
index 4679dbb..bdb0689 100644
--- a/lib/devres.c
+++ b/lib/devres.c
@@ -157,8 +157,10 @@ __devm_ioremap_resource(struct device *dev, const struct resource *res,
 					     dev_name(dev), res->name);
 	else
 		pretty_name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
-	if (!pretty_name)
+	if (!pretty_name) {
+		dev_err(dev, "can't generate pretty name for resource %pR\n", res);
 		return IOMEM_ERR_PTR(-ENOMEM);
+	}
 
 	if (!devm_request_mem_region(dev, res->start, size, pretty_name)) {
 		dev_err(dev, "can't request region for resource %pR\n", res);