[PATCH] dmaengine: mv_xor: use devm_platform_ioremap_resource()

[Rosen Penev]

Replace the two open-coded platform_get_resource() plus devm_ioremap()
sequences with devm_platform_ioremap_resource() for the low and high XOR
register windows. This folds the resource lookup and mapping into a
single call and returns an ERR_PTR on failure, checked with IS_ERR() and
propagated via PTR_ERR().

devm_platform_ioremap_resource() reserves the region via
devm_request_mem_region(), which requires non-overlapping reg ranges. All
XOR nodes in the Marvell DTS describe two distinct 0x100 register windows
that do not overlap each other, and sibling XOR nodes interleave without
overlapping, so the newly-reserving mapping introduces no region
conflict.

Built for ARM (defconfig + CONFIG_MV_XOR) with LLVM=1;
drivers/dma/mv_xor.o compiles cleanly.

Assisted-by: opencode:hy3-free
Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
---
 drivers/dma/mv_xor.c | 23 ++++++-----------------
 1 file changed, 6 insertions(+), 17 deletions(-)

diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
index 25ed61f1b089..fe2e6b9ec185 100644
--- a/drivers/dma/mv_xor.c
+++ b/drivers/dma/mv_xor.c
@@ -1309,7 +1309,6 @@ static int mv_xor_probe(struct platform_device *pdev)
 	const struct mbus_dram_target_info *dram;
 	struct mv_xor_device *xordev;
 	struct mv_xor_platform_data *pdata = dev_get_platdata(&pdev->dev);
-	struct resource *res;
 	unsigned int max_engines, max_channels;
 	int i, ret;
 
@@ -1319,23 +1318,13 @@ static int mv_xor_probe(struct platform_device *pdev)
 	if (!xordev)
 		return -ENOMEM;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res)
-		return -ENODEV;
+	xordev->xor_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(xordev->xor_base))
+		return PTR_ERR(xordev->xor_base);
 
-	xordev->xor_base = devm_ioremap(&pdev->dev, res->start,
-					resource_size(res));
-	if (!xordev->xor_base)
-		return -EBUSY;
-
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
-	if (!res)
-		return -ENODEV;
-
-	xordev->xor_high_base = devm_ioremap(&pdev->dev, res->start,
-					     resource_size(res));
-	if (!xordev->xor_high_base)
-		return -EBUSY;
+	xordev->xor_high_base = devm_platform_ioremap_resource(pdev, 1);
+	if (IS_ERR(xordev->xor_high_base))
+		return PTR_ERR(xordev->xor_high_base);
 
 	platform_set_drvdata(pdev, xordev);
 
-- 
2.55.0