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, 78 insertions, 0 deletions

diff --git a/drivers/thunderbolt/Kconfig b/drivers/thunderbolt/Kconfig
new file mode 100644
index 000000000..294b3227a
--- /dev/null
+++ b/drivers/thunderbolt/Kconfig
@@ -0,0 +1,78 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menuconfig USB4
+	tristate "Unified support for USB4 and Thunderbolt"
+	depends on PCI
+	select APPLE_PROPERTIES if EFI_STUB && X86
+	select CRC32
+	select CRYPTO_LIB_SHA256
+	select CRYPTO_LIB_UTILS
+	select NVMEM
+	help
+	  USB4 and Thunderbolt driver. USB4 is the public specification
+	  based on the Thunderbolt 3 protocol. This driver is required if
+	  you want to hotplug Thunderbolt and USB4 compliant devices on
+	  Apple hardware or on PCs with Intel Falcon Ridge or newer.
+
+	  To compile this driver a module, choose M here. The module will be
+	  called thunderbolt.
+
+if USB4
+
+config USB4_CONFIGFS
+	def_tristate USB4
+	depends on CONFIGFS_FS && !(USB4=y && CONFIGFS_FS=m)
+
+config USB4_DEBUGFS_WRITE
+	bool "Enable write by debugfs to configuration spaces (DANGEROUS)"
+	help
+	  Enables writing to device configuration registers through
+	  debugfs interface. You can use tools such as Thunderbolt/USB4
+	  debugging tools to access these registers. For more
+	  information see:
+
+	    https://github.com/intel/tbtools
+
+	  Only enable this if you know what you are doing! Never enable
+	  this for production systems or distro kernels.
+
+config USB4_DEBUGFS_MARGINING
+	bool "Expose receiver lane margining operations under USB4 ports and retimers (DANGEROUS)"
+	depends on DEBUG_FS
+	depends on USB4_DEBUGFS_WRITE
+	help
+	  Enables hardware and software based receiver lane margining
+	  support under each USB4 port and retimer, including retimers
+	  on the other side of the cable. Used for electrical quality
+	  and robustness validation during manufacturing. Should not be
+	  enabled by distro kernels.
+
+config USB4_KUNIT_TEST
+	bool "KUnit tests" if !KUNIT_ALL_TESTS
+	depends on USB4 && KUNIT=y
+	default KUNIT_ALL_TESTS
+
+config USB4_DMA_TEST
+	tristate "DMA traffic test driver"
+	depends on DEBUG_FS
+	help
+	  This allows sending and receiving DMA traffic through loopback
+	  connection. Loopback connection can be done by either special
+	  dongle that has TX/RX lines crossed, or by simply connecting a
+	  cable back to the host. Only enable this if you know what you
+	  are doing. Normal users and distro kernels should say N here.
+
+	  To compile this driver a module, choose M here. The module will be
+	  called thunderbolt_dma_test.
+
+config USB4_STREAM
+	tristate "Stream data over Thunderbolt/USB4 cable"
+	depends on USB4_CONFIGFS
+	help
+	  This adds support for USB4STREAM protocol that allows two
+	  hosts to stream data directly over Thunderbolt/USB4 cable
+	  through /dev/tbstreamX devices.
+
+	  To compile this driver a module, choose M here. The module will be
+	  called thunderbolt_stream.
+
+endif # USB4