Re: [PATCHv2] PCI: xilinx: use fwnode_irq_get() for INTx IRQ lookup

[Rosen Penev]

On Wed, Jul 29, 2026 at 9:00 AM Manivannan Sadhasivam <mani@xxxxxxxxxx> wrote:
>
> On Thu, Jul 16, 2026 at 01:58:11PM -0700, Rosen Penev wrote:
> > 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.
> >
>
> What is the benefit of using fwnode API for OF only driver?
I get conflicting information. Apparently of_irq_get needs a call to
irq_dispose_mapping but fwnode_irq_get does not. irq_of_parse_and_map
definitely does.
>
> - Mani
>
> > 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@xxxxxxxxx>
> > ---
> >  v2: use dev_err_probe to handle EPROBE_DEFER.
> >  drivers/pci/controller/pcie-xilinx.c | 15 ++++++++-------
> >  1 file changed, 8 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/pci/controller/pcie-xilinx.c b/drivers/pci/controller/pcie-xilinx.c
> > index 4aa139abac16..58532296182f 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);
> > @@ -585,10 +588,8 @@ static int xilinx_pcie_probe(struct platform_device *pdev)
> >       pcie->dev = dev;
> >
> >       err = xilinx_pcie_parse_dt(pcie);
> > -     if (err) {
> > -             dev_err(dev, "Parsing DT failed\n");
> > -             return err;
> > -     }
> > +     if (err)
> > +             return dev_err_probe(dev, err, "Parsing DT failed\n");
> >
> >       xilinx_pcie_init_port(pcie);
> >
> > --
> > 2.55.0
> >
>
> --
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