[PATCH] misc: aspeed-lpc-ctrl: make memory-region optional

[Vijay Khemka]

Makiing memory-region as optional parameter in device tree if
user needs to use memory-region then define in devicetree.

Signed-off-by: Vijay Khemka <vijaykhemka at fb.com>
---
 drivers/misc/aspeed-lpc-ctrl.c | 30 ++++++++++++++++++------------
 1 file changed, 18 insertions(+), 12 deletions(-)

diff --git a/drivers/misc/aspeed-lpc-ctrl.c b/drivers/misc/aspeed-lpc-ctrl.c
index a024f8042259..20507f0764fb 100644
--- a/drivers/misc/aspeed-lpc-ctrl.c
+++ b/drivers/misc/aspeed-lpc-ctrl.c
@@ -90,6 +90,10 @@ static long aspeed_lpc_ctrl_ioctl(struct file *file, unsigned int cmd,
 		if (map.window_id != 0)
 			return -EINVAL;
 
+		/* If memory-region is not described in device tree */
+		if (!lpc_ctrl->mem_size)
+			return -EINVAL;
+
 		map.size = lpc_ctrl->mem_size;
 
 		return copy_to_user(p, &map, sizeof(map)) ? -EFAULT : 0;
@@ -129,6 +133,10 @@ static long aspeed_lpc_ctrl_ioctl(struct file *file, unsigned int cmd,
 			addr = lpc_ctrl->pnor_base;
 			size = lpc_ctrl->pnor_size;
 		} else if (map.window_type == ASPEED_LPC_CTRL_WINDOW_MEMORY) {
+			/* If memory-region is not described in device tree */
+			if (!lpc_ctrl->mem_size)
+				return -EINVAL;
+
 			addr = lpc_ctrl->mem_base;
 			size = lpc_ctrl->mem_size;
 		} else {
@@ -214,22 +222,20 @@ static int aspeed_lpc_ctrl_probe(struct platform_device *pdev)
 
 	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_err(dev, "Didn't find reserved memory\n");
-		return -EINVAL;
-	}
+	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 -ENOMEM;
+		}
 
-	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 -ENOMEM;
+		lpc_ctrl->mem_size = resource_size(&resm);
+		lpc_ctrl->mem_base = resm.start;
 	}
 
-	lpc_ctrl->mem_size = resource_size(&resm);
-	lpc_ctrl->mem_base = resm.start;
-
 	lpc_ctrl->regmap = syscon_node_to_regmap(
 			pdev->dev.parent->of_node);
 	if (IS_ERR(lpc_ctrl->regmap)) {
-- 
2.17.1