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, 25 insertions, 0 deletions

diff --git a/net/packet/Kconfig b/net/packet/Kconfig
new file mode 100644
index 000000000..2997382d5
--- /dev/null
+++ b/net/packet/Kconfig
@@ -0,0 +1,25 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Packet configuration
+#
+
+config PACKET
+	tristate "Packet socket"
+	help
+	  The Packet protocol is used by applications which communicate
+	  directly with network devices without an intermediate network
+	  protocol implemented in the kernel, e.g. tcpdump.  If you want them
+	  to work, choose Y.
+
+	  To compile this driver as a module, choose M here: the module will
+	  be called af_packet.
+
+	  If unsure, say Y.
+
+config PACKET_DIAG
+	tristate "Packet: sockets monitoring interface"
+	depends on PACKET
+	default n
+	help
+	  Support for PF_PACKET sockets monitoring interface used by the ss tool.
+	  If unsure, say Y.