[PATCH] mtd: mpc5121_nfc: use platform for irq and ioremap

[Rosen Penev <rosenp@gmail.com>]

Replace the open-coded of_address_to_resource() plus devm_request_mem_region()
and devm_ioremap() sequence with a single devm_platform_ioremap_resource()
call, which folds the resource lookup, region reservation and mapping into
one step and returns an ERR_PTR on failure, checked with IS_ERR() and
propagated via PTR_ERR().

Switch IRQ acquisition from irq_of_parse_and_map() to platform_get_irq(),
which only retrieves the interrupt the OF/platform core has already set up
rather than transferring mapping ownership to the driver. Drop the now
unneeded of_irq.h include.

This is behaviorally equivalent: the driver already reserved the region
with devm_request_mem_region(), so the non-overlapping reg requirement of
devm_platform_ioremap_resource() was already satisfied.

Drop the now-unused regs_paddr / regs_size locals, which previously only
fed the open-coded request/ioremap calls. Keep the linux/of_address.h
include, as of_iomap() is still used elsewhere in the driver.

Built for PowerPC (mpc512x_defconfig + CONFIG_MTD_NAND_MPC5121_NFC) with
LLVM=1; drivers/mtd/nand/raw/mpc5121_nfc.o compiles cleanly.

Assisted-by: opencode:hy3-free
Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/mtd/nand/raw/mpc5121_nfc.c | 39 +++++++++---------------------
 1 file changed, 12 insertions(+), 27 deletions(-)

diff --git a/drivers/mtd/nand/raw/mpc5121_nfc.c b/drivers/mtd/nand/raw/mpc5121_nfc.c
index 97b4e7f3e1bb..e6594548b7e0 100644
--- a/drivers/mtd/nand/raw/mpc5121_nfc.c
+++ b/drivers/mtd/nand/raw/mpc5121_nfc.c
@@ -23,7 +23,6 @@
 #include <linux/mtd/partitions.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
-#include <linux/of_irq.h>
 #include <linux/platform_device.h>
 
 #include <asm/mpc5121.h>
@@ -618,14 +617,14 @@ static int mpc5121_nfc_probe(struct platform_device *op)
 	struct clk *clk;
 	struct device *dev = &op->dev;
 	struct mpc5121_nfc_prv *prv;
-	struct resource res;
 	struct mtd_info *mtd;
 	struct nand_chip *chip;
-	unsigned long regs_paddr, regs_size;
 	const __be32 *chips_no;
+	void __iomem *regs;
 	int resettime = 0;
 	int retval = 0;
 	int rev, len;
+	int irq;
 
 	/*
 	 * Check SoC revision. This driver supports only NFC
@@ -637,6 +636,14 @@ static int mpc5121_nfc_probe(struct platform_device *op)
 		return -ENXIO;
 	}
 
+	regs = devm_platform_ioremap_resource(op, 0);
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
+
+	irq = platform_get_irq(op, 0);
+	if (irq < 0)
+		return irq;
+
 	prv = devm_kzalloc(dev, sizeof(*prv), GFP_KERNEL);
 	if (!prv)
 		return -ENOMEM;
@@ -660,17 +667,7 @@ static int mpc5121_nfc_probe(struct platform_device *op)
 		return retval;
 	}
 
-	prv->irq = irq_of_parse_and_map(dn, 0);
-	if (!prv->irq) {
-		dev_err(dev, "Error mapping IRQ!\n");
-		return -EINVAL;
-	}
-
-	retval = of_address_to_resource(dn, 0, &res);
-	if (retval) {
-		dev_err(dev, "Error parsing memory region!\n");
-		return retval;
-	}
+	prv->irq = irq;
 
 	chips_no = of_get_property(dn, "chips", &len);
 	if (!chips_no || len != sizeof(*chips_no)) {
@@ -678,19 +675,7 @@ static int mpc5121_nfc_probe(struct platform_device *op)
 		return -EINVAL;
 	}
 
-	regs_paddr = res.start;
-	regs_size = resource_size(&res);
-
-	if (!devm_request_mem_region(dev, regs_paddr, regs_size, DRV_NAME)) {
-		dev_err(dev, "Error requesting memory region!\n");
-		return -EBUSY;
-	}
-
-	prv->regs = devm_ioremap(dev, regs_paddr, regs_size);
-	if (!prv->regs) {
-		dev_err(dev, "Error mapping memory region!\n");
-		return -ENOMEM;
-	}
+	prv->regs = regs;
 
 	mtd->name = "MPC5121 NAND";
 	chip->legacy.dev_ready = mpc5121_nfc_dev_ready;
-- 
2.55.0