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, 49 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-driver-xdata b/Documentation/ABI/testing/sysfs-driver-xdata
new file mode 100644
index 000000000..f574e8e6d
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-xdata
@@ -0,0 +1,49 @@
+What:		/sys/class/misc/drivers/dw-xdata-pcie.<device>/write
+Date:		April 2021
+KernelVersion:	5.13
+Contact:	Gustavo Pimentel <gustavo.pimentel@synopsys.com>
+Description:	Allows the user to enable the PCIe traffic generator which
+		will create write TLPs frames - from the Root Complex to the
+		Endpoint direction or to disable the PCIe traffic generator
+		in all directions.
+
+		Write y/1/on to enable, n/0/off to disable
+
+		Usage e.g.
+		 echo 1 > /sys/class/misc/dw-xdata-pcie.<device>/write
+		or
+		 echo 0 > /sys/class/misc/dw-xdata-pcie.<device>/write
+
+		The user can read the current PCIe link throughput generated
+		through this generator in MB/s.
+
+		Usage e.g.
+		 cat /sys/class/misc/dw-xdata-pcie.<device>/write
+		 204
+
+		The file is read and write.
+
+What:		/sys/class/misc/dw-xdata-pcie.<device>/read
+Date:		April 2021
+KernelVersion:	5.13
+Contact:	Gustavo Pimentel <gustavo.pimentel@synopsys.com>
+Description:	Allows the user to enable the PCIe traffic generator which
+		will create read TLPs frames - from the Endpoint to the Root
+		Complex direction or to disable the PCIe traffic generator
+                in all directions.
+
+		Write y/1/on to enable, n/0/off to disable
+
+		Usage e.g.
+		 echo 1 > /sys/class/misc/dw-xdata-pcie.<device>/read
+		or
+		 echo 0 > /sys/class/misc/dw-xdata-pcie.<device>/read
+
+		The user can read the current PCIe link throughput generated
+		through this generator in MB/s.
+
+		Usage e.g.
+		 cat /sys/class/misc/dw-xdata-pcie.<device>/read
+		 199
+
+		The file is read and write.