PCI: Add pci_irq_type() to query the allocated interrupt typegrafted

Add a helper that returns PCI_IRQ_MSIX, PCI_IRQ_MSI, or PCI_IRQ_INTX
based on the interrupt type the PCI core selected after
pci_alloc_irq_vectors().

Several drivers already open-code this check against pdev->msix_enabled
and pdev->msi_enabled, or even open code this helper [1].

A common helper avoids the duplication and keeps drivers from accessing
the bitfield directly (see also [2]).

Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: John Hubbard <jhubbard@nvidia.com>
Link: https://elixir.bootlin.com/linux/v7.1/source/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c#L196 [1]
Inspired-by: John Hubbard <jhubbard@nvidia.com>
Link: https://lore.kernel.org/all/DKKG2QM3YJYB.Z2H2B2UXJ75N@kernel.org/ [2]
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260813165234.620555-5-dakr@kernel.org
[ Add missing pci_irq_type() stub for CONFIG_PCI=n. ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>

1 files changed, 68 insertions, 0 deletions

diff --git a/include/asm-generic/Kbuild b/include/asm-generic/Kbuild
new file mode 100644
index 000000000..15df9dcb4
--- /dev/null
+++ b/include/asm-generic/Kbuild
@@ -0,0 +1,68 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# asm headers that all architectures except um should have
+# (This file is not included when SRCARCH=um since UML borrows several
+# asm headers from the host architecture.)
+
+mandatory-y += atomic.h
+mandatory-y += archrandom.h
+mandatory-y += barrier.h
+mandatory-y += bitops.h
+mandatory-y += bug.h
+mandatory-y += cacheflush.h
+mandatory-y += cfi.h
+mandatory-y += checksum.h
+mandatory-y += compat.h
+mandatory-y += current.h
+mandatory-y += delay.h
+mandatory-y += device.h
+mandatory-y += div64.h
+mandatory-y += dma-mapping.h
+mandatory-y += dma.h
+mandatory-y += emergency-restart.h
+mandatory-y += exec.h
+mandatory-y += ftrace.h
+mandatory-y += futex.h
+mandatory-y += hardirq.h
+mandatory-y += hw_irq.h
+mandatory-y += io.h
+mandatory-y += irq.h
+mandatory-y += irq_regs.h
+mandatory-y += irq_work.h
+mandatory-y += kdebug.h
+mandatory-y += kmap_size.h
+mandatory-y += kprobes.h
+mandatory-y += kvm_types.h
+mandatory-y += linkage.h
+mandatory-y += local.h
+mandatory-y += local64.h
+mandatory-y += mmiowb.h
+mandatory-y += mmu.h
+mandatory-y += mmu_context.h
+mandatory-y += module.h
+mandatory-y += module.lds.h
+mandatory-y += msi.h
+mandatory-y += pci.h
+mandatory-y += percpu.h
+mandatory-y += percpu_types.h
+mandatory-y += pgalloc.h
+mandatory-y += preempt.h
+mandatory-y += rqspinlock.h
+mandatory-y += runtime-const.h
+mandatory-y += rwonce.h
+mandatory-y += sections.h
+mandatory-y += serial.h
+mandatory-y += shmparam.h
+mandatory-y += simd.h
+mandatory-y += softirq_stack.h
+mandatory-y += switch_to.h
+mandatory-y += timex.h
+mandatory-y += tlbflush.h
+mandatory-y += topology.h
+mandatory-y += trace_clock.h
+mandatory-y += uaccess.h
+mandatory-y += unwind_user.h
+mandatory-y += vermagic.h
+mandatory-y += vga.h
+mandatory-y += video.h
+mandatory-y += word-at-a-time.h