[PATCH] mailbox: test: really ignore optional memory resources

From: Wolfram Sang

Date: Tue Feb 17 2026 - 09:06:39 EST


Memory resources are optional but if the resource is empty
devm_platform_get_and_ioremap_resource() prints an error nonetheless.
Refactor the code to check the resources locally first and process them
only if they are present.

Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
---
drivers/mailbox/mailbox-test.c | 32 +++++++++++++++++++-------------
1 file changed, 19 insertions(+), 13 deletions(-)

diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c
index 3a28ab5c42e5..98c2a2ed6dfc 100644
--- a/drivers/mailbox/mailbox-test.c
+++ b/drivers/mailbox/mailbox-test.c
@@ -367,22 +367,28 @@ static int mbox_test_probe(struct platform_device *pdev)
return -ENOMEM;

/* It's okay for MMIO to be NULL */
- tdev->tx_mmio = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
- if (PTR_ERR(tdev->tx_mmio) == -EBUSY) {
- /* if reserved area in SRAM, try just ioremap */
- size = resource_size(res);
- tdev->tx_mmio = devm_ioremap(&pdev->dev, res->start, size);
- } else if (IS_ERR(tdev->tx_mmio)) {
- tdev->tx_mmio = NULL;
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (res) {
+ tdev->tx_mmio = devm_ioremap_resource(&pdev->dev, res);
+ if (PTR_ERR(tdev->tx_mmio) == -EBUSY) {
+ /* if reserved area in SRAM, try just ioremap */
+ size = resource_size(res);
+ tdev->tx_mmio = devm_ioremap(&pdev->dev, res->start, size);
+ } else if (IS_ERR(tdev->tx_mmio)) {
+ tdev->tx_mmio = NULL;
+ }
}

/* If specified, second reg entry is Rx MMIO */
- tdev->rx_mmio = devm_platform_get_and_ioremap_resource(pdev, 1, &res);
- if (PTR_ERR(tdev->rx_mmio) == -EBUSY) {
- size = resource_size(res);
- tdev->rx_mmio = devm_ioremap(&pdev->dev, res->start, size);
- } else if (IS_ERR(tdev->rx_mmio)) {
- tdev->rx_mmio = tdev->tx_mmio;
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (res) {
+ tdev->rx_mmio = devm_ioremap_resource(&pdev->dev, res);
+ if (PTR_ERR(tdev->rx_mmio) == -EBUSY) {
+ size = resource_size(res);
+ tdev->rx_mmio = devm_ioremap(&pdev->dev, res->start, size);
+ } else if (IS_ERR(tdev->rx_mmio)) {
+ tdev->rx_mmio = tdev->tx_mmio;
+ }
}

tdev->tx_channel = mbox_test_request_channel(pdev, "tx");
--
2.47.3