soc: aspeed: Use of_reserved_mem_region_to_resource() for "memory-region"

Use the newly added of_reserved_mem_region_to_resource() function to
handle "memory-region" properties.

The error handling is a bit different. "memory-region" is optional, so
failed lookup is not an error. But then an error in
of_address_to_resource() is treated as an error. However, that
distinction is not really important. Either the region is available
and usable or it is not. So now, it is just
of_reserved_mem_region_to_resource() which is checked for an error.

Signed-off-by: Rob Herring (Arm) <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Andrew Jeffery <[e-mail]>

drivers/soc/aspeed/aspeed-lpc-ctrl.c

···
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/of_address.h>
+#include <linux/of_reserved_mem.h>
 #include <linux/platform_device.h>
 #include <linux/poll.h>
 #include <linux/regmap.h>
···
 	dev_set_drvdata(&pdev->dev, lpc_ctrl);
 
 	/* If memory-region is described in device tree then store */
-	node = of_parse_phandle(dev->of_node, "memory-region", 0);
-	if (!node) {
-		dev_dbg(dev, "Didn't find reserved memory\n");
-	} else {
-		rc = of_address_to_resource(node, 0, &resm);
-		of_node_put(node);
-		if (rc) {
-			dev_err(dev, "Couldn't address to resource for reserved memory\n");
-			return -ENXIO;
-		}
-
+	rc = of_reserved_mem_region_to_resource(dev->of_node, 0, &resm);
+	if (!rc) {
 		lpc_ctrl->mem_size = resource_size(&resm);
 		lpc_ctrl->mem_base = resm.start;
 

drivers/soc/aspeed/aspeed-p2a-ctrl.c

···
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/of.h>
-#include <linux/of_address.h>
+#include <linux/of_reserved_mem.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
 #include <linux/slab.h>
···
 	struct aspeed_p2a_ctrl *misc_ctrl;
 	struct device *dev;
 	struct resource resm;
-	struct device_node *node;
 	int rc = 0;
 
 	dev = &pdev->dev;
···
 	mutex_init(&misc_ctrl->tracking);
 
 	/* optional. */
-	node = of_parse_phandle(dev->of_node, "memory-region", 0);
-	if (node) {
-		rc = of_address_to_resource(node, 0, &resm);
-		of_node_put(node);
-		if (rc) {
-			dev_err(dev, "Couldn't address to resource for reserved memory\n");
-			return -ENODEV;
-		}
-
+	rc = of_reserved_mem_region_to_resource(dev->of_node, 0, &resm);
+	if (!rc) {
 		misc_ctrl->mem_size = resource_size(&resm);
 		misc_ctrl->mem_base = resm.start;
 	}