[PATCH] PCI: xilinx: use fwnode_irq_get() for INTx IRQ lookup

[Rosen Penev <rosenp@gmail.com>]

Replace irq_of_parse_and_map() with fwnode_irq_get(dev_fwnode(dev), 0)
in xilinx_pcie_parse_dt(). For an OF-backed device this is equivalent to
the previous call, but uses the generic firmware-node API.

Unlike irq_of_parse_and_map(), fwnode_irq_get() returns a positive IRQ or
a negative errno and never 0 (it rewrites 0 to -EINVAL). Store the result
in an int and check for irq < 0, returning the error (including
-EPROBE_DEFER). This also adds the error handling the previous code
lacked, where irq_of_parse_and_map() failures were passed straight into
devm_request_irq().

Built for ARM (multi_v7_defconfig + CONFIG_PCIE_XILINX) with LLVM=1;
drivers/pci/controller/pcie-xilinx.o compiles cleanly.

Assisted-by: opencode:hy3-free
Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/pci/controller/pcie-xilinx.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/controller/pcie-xilinx.c b/drivers/pci/controller/pcie-xilinx.c
index 4aa139abac16..a7b069f7673a 100644
--- a/drivers/pci/controller/pcie-xilinx.c
+++ b/drivers/pci/controller/pcie-xilinx.c
@@ -20,10 +20,10 @@
 #include <linux/of_address.h>
 #include <linux/of_pci.h>
 #include <linux/of_platform.h>
-#include <linux/of_irq.h>
 #include <linux/pci.h>
 #include <linux/pci-ecam.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 
 #include "../pci.h"
 
@@ -535,7 +535,7 @@ static int xilinx_pcie_parse_dt(struct xilinx_pcie *pcie)
 	struct device *dev = pcie->dev;
 	struct device_node *node = dev->of_node;
 	struct resource regs;
-	unsigned int irq;
+	int irq;
 	int err;
 
 	err = of_address_to_resource(node, 0, &regs);
@@ -548,7 +548,10 @@ static int xilinx_pcie_parse_dt(struct xilinx_pcie *pcie)
 	if (IS_ERR(pcie->reg_base))
 		return PTR_ERR(pcie->reg_base);
 
-	irq = irq_of_parse_and_map(node, 0);
+	irq = fwnode_irq_get(dev_fwnode(dev), 0);
+	if (irq < 0)
+		return irq;
+
 	err = devm_request_irq(dev, irq, xilinx_pcie_intr_handler,
 			       IRQF_SHARED | IRQF_NO_THREAD,
 			       "xilinx-pcie", pcie);
-- 
2.55.0