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>

13 files changed, 65 insertions, 0 deletions

diff --git a/usr/dummy-include/endian.h b/usr/dummy-include/endian.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/endian.h
diff --git a/usr/dummy-include/limits.h b/usr/dummy-include/limits.h
new file mode 100644
index 000000000..49b17c10c
--- /dev/null
+++ b/usr/dummy-include/limits.h
@@ -0,0 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _DUMMY_LIMITS_H
+#define _DUMMY_LIMITS_H
+
+#define INT_MAX ((int)(~0U >> 1))
+#define INT_MIN (-INT_MAX - 1)
+
+#endif /* _DUMMY_LIMITS_H */
diff --git a/usr/dummy-include/netinet/if_ether.h b/usr/dummy-include/netinet/if_ether.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/netinet/if_ether.h
diff --git a/usr/dummy-include/netinet/in.h b/usr/dummy-include/netinet/in.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/netinet/in.h
diff --git a/usr/dummy-include/stddef.h b/usr/dummy-include/stddef.h
new file mode 100644
index 000000000..525489daf
--- /dev/null
+++ b/usr/dummy-include/stddef.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _DUMMY_STDDEF_H
+#define _DUMMY_STDDEF_H
+
+#define offsetof(TYPE, MEMBER)	__builtin_offsetof(TYPE, MEMBER)
+
+#ifdef __cplusplus
+#define NULL 0
+#else
+#define NULL ((void *)0)
+#endif
+
+#endif /* _DUMMY_STDDEF_H */
diff --git a/usr/dummy-include/stdint.h b/usr/dummy-include/stdint.h
new file mode 100644
index 000000000..93b1962fd
--- /dev/null
+++ b/usr/dummy-include/stdint.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _DUMMY_STDINT_H
+#define _DUMMY_STDINT_H
+
+#include <linux/types.h>
+
+typedef	__u64	uint64_t;
+typedef	__u32	uint32_t;
+typedef	__u16	uint16_t;
+typedef	__u8	uint8_t;
+
+typedef	__s64	int64_t;
+typedef	__s32	int32_t;
+typedef	__s16	int16_t;
+typedef	__s8	int8_t;
+
+#endif /* _DUMMY_STDINT_H */
diff --git a/usr/dummy-include/string.h b/usr/dummy-include/string.h
new file mode 100644
index 000000000..e059808d3
--- /dev/null
+++ b/usr/dummy-include/string.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _DUMMY_STRING_H
+#define _DUMMY_STRING_H
+
+#include <stddef.h>
+
+#define memset(_s, _c, _n) __builtin_memset(_s, _c, _n)
+#define memcpy(_dest, _src, _n) __builtin_memcpy(_dest, _src, _n)
+
+#define strlen(_s) __builtin_strlen(_s)
+
+#endif /* _DUMMY_STRING_H */
diff --git a/usr/dummy-include/sys/ioctl.h b/usr/dummy-include/sys/ioctl.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/sys/ioctl.h
diff --git a/usr/dummy-include/sys/socket.h b/usr/dummy-include/sys/socket.h
new file mode 100644
index 000000000..748751f9e
--- /dev/null
+++ b/usr/dummy-include/sys/socket.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _DUMMY_SYS_SOCKET_H
+#define _DUMMY_SYS_SOCKET_H
+
+#include <linux/socket.h>
+
+struct sockaddr {
+	__kernel_sa_family_t	sa_family;	/* address family, AF_xxx	*/
+	char			sa_data[14];	/* 14 bytes of protocol address	*/
+};
+
+#endif /* _DUMMY_SYS_SOCKET_H */
diff --git a/usr/dummy-include/sys/time.h b/usr/dummy-include/sys/time.h
new file mode 100644
index 000000000..9817b8afb
--- /dev/null
+++ b/usr/dummy-include/sys/time.h
@@ -0,0 +1,3 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <linux/time.h>
diff --git a/usr/dummy-include/sys/types.h b/usr/dummy-include/sys/types.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/sys/types.h
diff --git a/usr/dummy-include/time.h b/usr/dummy-include/time.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/time.h
diff --git a/usr/dummy-include/unistd.h b/usr/dummy-include/unistd.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/unistd.h