code:
What:		/sys/bus/pci/drivers/.../bind
What:		/sys/devices/pciX/.../bind
Date:		December 2003
Contact:	linux-pci@vger.kernel.org
Description:
		Writing a device location to this file will cause
		the driver to attempt to bind to the device found at
		this location.	This is useful for overriding default
		bindings.  The format for the location is: DDDD:BB:DD.F.
		That is Domain:Bus:Device.Function and is the same as
		found in /sys/bus/pci/devices/.  For example::

		  # echo 0000:00:19.0 > /sys/bus/pci/drivers/foo/bind

		(Note: kernels before 2.6.28 may require echo -n).

What:		/sys/bus/pci/drivers/.../unbind
What:		/sys/devices/pciX/.../unbind
Date:		December 2003
Contact:	linux-pci@vger.kernel.org
Description:
		Writing a device location to this file will cause the
		driver to attempt to unbind from the device found at
		this location.	This may be useful when overriding default
		bindings.  The format for the location is: DDDD:BB:DD.F.
		That is Domain:Bus:Device.Function and is the same as
		found in /sys/bus/pci/devices/. For example::

		  # echo 0000:00:19.0 > /sys/bus/pci/drivers/foo/unbind

		(Note: kernels before 2.6.28 may require echo -n).

What:		/sys/bus/pci/drivers/.../new_id
What:		/sys/devices/pciX/.../new_id
Date:		December 2003
Contact:	linux-pci@vger.kernel.org
Description:
		Writing a device ID to this file will attempt to
		dynamically add a new device ID to a PCI device driver.
		This may allow the driver to support more hardware than
		was included in the driver's static device ID support
		table at compile time.  The format for the device ID is:
		VVVV DDDD SVVV SDDD CCCC MMMM PPPP.  That is Vendor ID,
		Device ID, Subsystem Vendor ID, Subsystem Device ID,
		Class, Class Mask, and Private Driver Data.  The Vendor ID
		and Device ID fields are required, the rest are optional.
		Upon successfully adding an ID, the driver will probe
		for the device and attempt to bind to it.  For example::

		  # echo "8086 10f5" > /sys/bus/pci/drivers/foo/new_id

What:		/sys/bus/pci/drivers/.../remove_id
What:		/sys/devices/pciX/.../remove_id
Date:		February 2009
Contact:	Chris Wright <chrisw@sous-sol.org>
Description:
		Writing a device ID to this file will remove an ID
		that was dynamically added via the new_id sysfs entry.
		The format for the device ID is:
		VVVV DDDD SVVV SDDD CCCC MMMM.	That is Vendor ID, Device
		ID, Subsystem Vendor ID, Subsystem Device ID, Class,
		and Class Mask.  The Vendor ID and Device ID fields are
		required, the rest are optional.  After successfully
		removing an ID, the driver will no longer support the
		device.  This is useful to ensure auto probing won't
		match the driver to the device.  For example::

		  # echo "8086 10f5" > /sys/bus/pci/drivers/foo/remove_id

What:		/sys/bus/pci/rescan
Date:		January 2009
Contact:	Linux PCI developers <linux-pci@vger.kernel.org>
Description:
		Writing a non-zero value to this attribute will
		force a rescan of all PCI buses in the system, and
		re-discover previously removed devices.

What:		/sys/bus/pci/devices/.../msi_bus
Date:		September 2014
Contact:	Linux PCI developers <linux-pci@vger.kernel.org>
Description:
		Writing a zero value to this attribute disallows MSI and
		MSI-X for any future drivers of the device.  If the device
		is a bridge, MSI and MSI-X will be disallowed for future
		drivers of all child devices under the bridge.  Drivers
		must be reloaded for the new setting to take effect.

What:		/sys/bus/pci/devices/.../msi_irqs/
Date:		September, 2011
Contact:	Neil Horman <nhorman@tuxdriver.com>
Description:
		The /sys/devices/.../msi_irqs directory contains a variable set
		of files, with each file being named after a corresponding msi
		irq vector allocated to that device.

What:		/sys/bus/pci/devices/.../msi_irqs/<N>
Date:		September 2011
Contact:	Neil Horman <nhorman@tuxdriver.com>
Description:
		This attribute indicates the mode that the irq vector named by
		the file is in (msi vs. msix)

What:		/sys/bus/pci/devices/.../irq
Date:		August 2021
Contact:	Linux PCI developers <linux-pci@vger.kernel.org>
Description:
		If a driver has enabled MSI (not MSI-X), "irq" contains the
		IRQ of the first MSI vector. Otherwise "irq" contains the
		IRQ of the legacy INTx interrupt.

		"irq" being set to 0 indicates that the device isn't
		capable of generating legacy INTx interrupts.

What:		/sys/bus/pci/devices/.../remove
Date:		January 2009
Contact:	Linux PCI developers <linux-pci@vger.kernel.org>
Description:
		Writing a non-zero value to this attribute will
		hot-remove the PCI device and any of its children.

What:		/sys/bus/pci/devices/.../pci_bus/.../rescan
Date:		May 2011
Contact:	Linux PCI developers <linux-pci@vger.kernel.org>
Description:
		Writing a non-zero value to this attribute will
		force a rescan of the bus and all child buses,
		and re-discover devices removed earlier from this
		part of the device tree.

What:		/sys/bus/pci/devices/.../rescan
Date:		January 2009
Contact:	Linux PCI developers <linux-pci@vger.kernel.org>
Description:
		Writing a non-zero value to this attribute will
		force a rescan of the device's parent bus and all
		child buses, and re-discover devices removed earlier
		from this part of the device tree.

What:		/sys/bus/pci/devices/.../reset_method
Date:		August 2021
Contact:	Amey Narkhede <ameynarkhede03@gmail.com>
Description:
		Some devices allow an individual function to be reset
		without affecting other functions in the same slot.

		For devices that have this support, a file named
		reset_method is present in sysfs.  Reading this file
		gives names of the supported and enabled reset methods and
		their ordering.  Writing a space-separated list of names of
		reset methods sets the reset methods and ordering to be
		used when resetting the device.  Writing an empty string
		disables the ability to reset the device.  Writing
		"default" enables all supported reset methods in the
		default ordering.

What:		/sys/bus/pci/devices/.../reset
Date:		July 2009
Contact:	Michael S. Tsirkin <mst@redhat.com>
Description:
		Some devices allow an individual function to be reset
		without affecting other functions in the same device.
		For devices that have this support, a file named reset
		will be present in sysfs.  Writing 1 to this file
		will perform reset.

What:		/sys/bus/pci/devices/.../vpd
Date:		February 2008
Contact:	Ben Hutchings <bwh@kernel.org>
Description:
		A file named vpd in a device directory will be a
		binary file containing the Vital Product Data for the
		device.  It should follow the VPD format defined in
		PCI Specification 2.1 or 2.2, but users should consider
		that some devices may have incorrectly formatted data.
		If the underlying VPD has a writable section then the
		corresponding section of this file will be writable.

What:		/sys/bus/pci/devices/.../virtfn<N>
Date:		March 2009
Contact:	Yu Zhao <yu.zhao@intel.com>
Description:
		This symbolic link appears when hardware supports the SR-IOV
		capability and the Physical Function driver has enabled it.
		The symbolic link points to the PCI device sysfs entry of the
		Virtual Function whose index is N (0...MaxVFs-1).

What:		/sys/bus/pci/devices/.../dep_link
Date:		March 2009
Contact:	Yu Zhao <yu.zhao@intel.com>
Description:
		This symbolic link appears when hardware supports the SR-IOV
		capability and the Physical Function driver has enabled it,
		and this device has vendor specific dependencies with others.
		The symbolic link points to the PCI device sysfs entry of
		Physical Function this device depends on.

What:		/sys/bus/pci/devices/.../physfn
Date:		March 2009
Contact:	Yu Zhao <yu.zhao@intel.com>
Description:
		This symbolic link appears when a device is a Virtual Function.
		The symbolic link points to the PCI device sysfs entry of the
		Physical Function this device associates with.

What:		/sys/bus/pci/devices/.../modalias
Date:		May 2005
Contact:	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Description:
		This attribute indicates the PCI ID of the device object.

		That is in the format:
		pci:vXXXXXXXXdXXXXXXXXsvXXXXXXXXsdXXXXXXXXbcXXscXXiXX,
		where:

		    - vXXXXXXXX contains the vendor ID;
		    - dXXXXXXXX contains the device ID;
		    - svXXXXXXXX contains the sub-vendor ID;
		    - sdXXXXXXXX contains the subsystem device ID;
		    - bcXX contains the device class;
		    - scXX contains the device subclass;
		    - iXX contains the device class programming interface.

What:		/sys/bus/pci/slots/.../module
Date:		June 2009
Contact:	linux-pci@vger.kernel.org
Description:
		This symbolic link points to the PCI hotplug controller driver
		module that manages the hotplug slot.

What:		/sys/bus/pci/devices/.../label
Date:		July 2010
Contact:	Narendra K <narendra_k@dell.com>, linux-bugs@dell.com
Description:
		Reading this attribute will provide the firmware
		given name (SMBIOS type 41 string or ACPI _DSM string) of
		the PCI device.	The attribute will be created only
		if the firmware	has given a name to the PCI device.
		ACPI _DSM string name will be given priority if the
		system firmware provides SMBIOS type 41 string also.
Users:
		Userspace applications interested in knowing the
		firmware assigned name of the PCI device.

What:		/sys/bus/pci/devices/.../index
Date:		July 2010
Contact:	Narendra K <narendra_k@dell.com>, linux-bugs@dell.com
Description:
		Reading this attribute will provide the firmware given instance
		number of the PCI device.  Depending on the platform this can
		be for example the SMBIOS type 41 device type instance or the
		user-defined ID (UID) on s390. The attribute will be created
		only if the firmware has given an instance number to the PCI
		device and that number is guaranteed to uniquely identify the
		device in the system.
Users:
		Userspace applications interested in knowing the
		firmware assigned device type instance of the PCI
		device that can help in understanding the firmware
		intended order of the PCI device.

What:		/sys/bus/pci/devices/.../acpi_index
Date:		July 2010
Contact:	Narendra K <narendra_k@dell.com>, linux-bugs@dell.com
Description:
		Reading this attribute will provide the firmware
		given instance (ACPI _DSM instance number) of the PCI device.
		The attribute will be created only if the firmware has given
		an instance number to the PCI device. ACPI _DSM instance number
		will be given priority if the system firmware provides SMBIOS
		type 41 device type instance also.
Users:
		Userspace applications interested in knowing the
		firmware assigned instance number of the PCI
		device that can help in understanding the firmware
		intended order of the PCI device.

What:		/sys/bus/pci/devices/.../d3cold_allowed
Date:		July 2012
Contact:	Huang Ying <ying.huang@intel.com>
Description:
		d3cold_allowed is bit to control whether the corresponding PCI
		device can be put into D3Cold state.  If it is cleared, the
		device will never be put into D3Cold state.  If it is set, the
		device may be put into D3Cold state if other requirements are
		satisfied too.  Reading this attribute will show the current
		value of d3cold_allowed bit.  Writing this attribute will set
		the value of d3cold_allowed bit.

What:		/sys/bus/pci/devices/.../sriov_totalvfs
Date:		November 2012
Contact:	Donald Dutile <ddutile@redhat.com>
Description:
		This file appears when a physical PCIe device supports SR-IOV.
		Userspace applications can read this file to determine the
		maximum number of Virtual Functions (VFs) a PCIe physical
		function (PF) can support. Typically, this is the value reported
		in the PF's SR-IOV extended capability structure's TotalVFs
		element.  Drivers have the ability at probe time to reduce the
		value read from this file via the pci_sriov_set_totalvfs()
		function.

What:		/sys/bus/pci/devices/.../sriov_numvfs
Date:		November 2012
Contact:	Donald Dutile <ddutile@redhat.com>
Description:
		This file appears when a physical PCIe device supports SR-IOV.
		Userspace applications can read and write to this file to
		determine and control the enablement or disablement of Virtual
		Functions (VFs) on the physical function (PF). A read of this
		file will return the number of VFs that are enabled on this PF.
		A number written to this file will enable the specified
		number of VFs. A userspace application would typically read the
		file and check that the value is zero, and then write the number
		of VFs that should be enabled on the PF; the value written
		should be less than or equal to the value in the sriov_totalvfs
		file. A userspace application wanting to disable the VFs would
		write a zero to this file. The core ensures that valid values
		are written to this file, and returns errors when values are not
		valid.  For example, writing a 2 to this file when sriov_numvfs
		is not 0 and not 2 already will return an error. Writing a 10
		when the value of sriov_totalvfs is 8 will return an error.

What:		/sys/bus/pci/devices/.../driver_override
Date:		April 2014
Contact:	Alex Williamson <alex.williamson@redhat.com>
Description:
		This file allows the driver for a device to be specified which
		will override standard static and dynamic ID matching.  When
		specified, only a driver with a name matching the value written
		to driver_override will have an opportunity to bind to the
		device.  The override is specified by writing a string to the
		driver_override file (echo pci-stub > driver_override) and
		may be cleared with an empty string (echo > driver_override).
		This returns the device to standard matching rules binding.
		Writing to driver_override does not automatically unbind the
		device from its current driver or make any attempt to
		automatically load the specified driver.  If no driver with a
		matching name is currently loaded in the kernel, the device
		will not bind to any driver.  This also allows devices to
		opt-out of driver binding using a driver_override name such as
		"none".  Only a single driver may be specified in the override,
		there is no support for parsing delimiters.

What:		/sys/bus/pci/devices/.../numa_node
Date:		Oct 2014
Contact:	Prarit Bhargava <prarit@redhat.com>
Description:
		This file contains the NUMA node to which the PCI device is
		attached, or -1 if the node is unknown.  The initial value
		comes from an ACPI _PXM method or a similar firmware
		source.  If that is missing or incorrect, this file can be
		written to override the node.  In that case, please report
		a firmware bug to the system vendor.  Writing to this file
		taints the kernel with TAINT_FIRMWARE_WORKAROUND, which
		reduces the supportability of your system.

What:		/sys/bus/pci/devices/.../revision
Date:		November 2016
Contact:	Emil Velikov <emil.l.velikov@gmail.com>
Description:
		This file contains the revision field of the PCI device.
		The value comes from device config space. The file is read only.

What:		/sys/bus/pci/devices/.../sriov_drivers_autoprobe
Date:		April 2017
Contact:	Bodong Wang<bodong@mellanox.com>
Description:
		This file is associated with the PF of a device that
		supports SR-IOV.  It determines whether newly-enabled VFs
		are immediately bound to a driver.  It initially contains
		1, which means the kernel automatically binds VFs to a
		compatible driver immediately after they are enabled.  If
		an application writes 0 to the file before enabling VFs,
		the kernel will not bind VFs to a driver.

		A typical use case is to write 0 to this file, then enable
		VFs, then assign the newly-created VFs to virtual machines.
		Note that changing this file does not affect already-
		enabled VFs.  In this scenario, the user must first disable
		the VFs, write 0 to sriov_drivers_autoprobe, then re-enable
		the VFs.

		This is similar to /sys/bus/pci/drivers_autoprobe, but
		affects only the VFs associated with a specific PF.

What:		/sys/bus/pci/devices/.../p2pmem/size
Date:		November 2017
Contact:	Logan Gunthorpe <logang@deltatee.com>
Description:
		If the device has any Peer-to-Peer memory registered, this
	        file contains the total amount of memory that the device
		provides (in decimal).

What:		/sys/bus/pci/devices/.../p2pmem/available
Date:		November 2017
Contact:	Logan Gunthorpe <logang@deltatee.com>
Description:
		If the device has any Peer-to-Peer memory registered, this
	        file contains the amount of memory that has not been
		allocated (in decimal).

What:		/sys/bus/pci/devices/.../p2pmem/published
Date:		November 2017
Contact:	Logan Gunthorpe <logang@deltatee.com>
Description:
		If the device has any Peer-to-Peer memory registered, this
	        file contains a '1' if the memory has been published for
		use outside the driver that owns the device.

What:		/sys/bus/pci/devices/.../p2pmem/allocate
Date:		August 2022
Contact:	Logan Gunthorpe <logang@deltatee.com>
Description:
		This file allows mapping p2pmem into userspace. For each
		mmap() call on this file, the kernel will allocate a chunk
		of Peer-to-Peer memory for use in Peer-to-Peer transactions.
		This memory can be used in O_DIRECT calls to NVMe backed
		files for Peer-to-Peer copies.

What:		/sys/bus/pci/devices/.../link/clkpm
		/sys/bus/pci/devices/.../link/l0s_aspm
		/sys/bus/pci/devices/.../link/l1_aspm
		/sys/bus/pci/devices/.../link/l1_1_aspm
		/sys/bus/pci/devices/.../link/l1_2_aspm
		/sys/bus/pci/devices/.../link/l1_1_pcipm
		/sys/bus/pci/devices/.../link/l1_2_pcipm
Date:		October 2019
Contact:	Heiner Kallweit <hkallweit1@gmail.com>
Description:	If ASPM is supported for an endpoint, these files can be
		used to disable or enable the individual power management
		states. Write y/1/on to enable, n/0/off to disable.

What:		/sys/bus/pci/devices/.../power_state
Date:		November 2020
Contact:	Linux PCI developers <linux-pci@vger.kernel.org>
Description:
		This file contains the current PCI power state of the device.
		The value comes from the PCI kernel device state and can be one
		of: "unknown", "error", "D0", D1", "D2", "D3hot", "D3cold".
		The file is read only.

What:		/sys/bus/pci/devices/.../sriov_vf_total_msix
Date:		January 2021
Contact:	Leon Romanovsky <leonro@nvidia.com>
Description:
		This file is associated with a SR-IOV physical function (PF).
		It contains the total number of MSI-X vectors available for
		assignment to all virtual functions (VFs) associated with PF.
		The value will be zero if the device doesn't support this
		functionality. For supported devices, the value will be
		constant and won't be changed after MSI-X vectors assignment.

What:		/sys/bus/pci/devices/.../sriov_vf_msix_count
Date:		January 2021
Contact:	Leon Romanovsky <leonro@nvidia.com>
Description:
		This file is associated with a SR-IOV virtual function (VF).
		It allows configuration of the number of MSI-X vectors for
		the VF. This allows devices that have a global pool of MSI-X
		vectors to optimally divide them between VFs based on VF usage.

		The values accepted are:
		 * > 0 - this number will be reported as the Table Size in the
			 VF's MSI-X capability
		 * < 0 - not valid
		 * = 0 - will reset to the device default value

		The file is writable if the PF is bound to a driver that
		implements ->sriov_set_msix_vec_count().

What:		/sys/bus/pci/devices/.../resourceN_resize
Date:		September 2022
Contact:	Alex Williamson <alex.williamson@redhat.com>
Description:
		These files provide an interface to PCIe Resizable BAR support.
		A file is created for each BAR resource (N) supported by the
		PCIe Resizable BAR extended capability of the device.  Reading
		each file exposes the bitmap of available resource sizes:

		# cat resource1_resize
		00000000000001c0

		The bitmap represents supported resource sizes for the BAR,
		where bit0 = 1MB, bit1 = 2MB, bit2 = 4MB, etc.  In the above
		example the device supports 64MB, 128MB, and 256MB BAR sizes.

		When writing the file, the user provides the bit position of
		the desired resource size, for example:

		# echo 7 > resource1_resize

		This indicates to set the size value corresponding to bit 7,
		128MB.  The resulting size is 2 ^ (bit# + 20).  This definition
		matches the PCIe specification of this capability.

		In order to make use of resource resizing, all PCI drivers must
		be unbound from the device and peer devices under the same
		parent bridge may need to be soft removed.  In the case of
		VGA devices, writing a resize value will remove low level
		console drivers from the device.  Raw users of pci-sysfs
		resourceN attributes must be terminated prior to resizing.
		Success of the resizing operation is not guaranteed.

path: Documentation/ABI/testing/sysfs-bus-pci


code:
PCIe Device AER statistics
--------------------------

These attributes show up under all the devices that are AER capable. These
statistical counters indicate the errors "as seen/reported by the device".
Note that this may mean that if an endpoint is causing problems, the AER
counters may increment at its link partner (e.g. root port) because the
errors may be "seen" / reported by the link partner and not the
problematic endpoint itself (which may report all counters as 0 as it never
saw any problems).

What:		/sys/bus/pci/devices/<dev>/aer_dev_correctable
Date:		July 2018
KernelVersion: 4.19.0
Contact:	linux-pci@vger.kernel.org, rajatja@google.com
Description:	List of correctable errors seen and reported by this
		PCI device using ERR_COR. Note that since multiple errors may
		be reported using a single ERR_COR message, thus
		TOTAL_ERR_COR at the end of the file may not match the actual
		total of all the errors in the file. Sample output::

		    localhost /sys/devices/pci0000:00/0000:00:1c.0 # cat aer_dev_correctable
		    Receiver Error 2
		    Bad TLP 0
		    Bad DLLP 0
		    RELAY_NUM Rollover 0
		    Replay Timer Timeout 0
		    Advisory Non-Fatal 0
		    Corrected Internal Error 0
		    Header Log Overflow 0
		    TOTAL_ERR_COR 2

What:		/sys/bus/pci/devices/<dev>/aer_dev_fatal
Date:		July 2018
KernelVersion: 4.19.0
Contact:	linux-pci@vger.kernel.org, rajatja@google.com
Description:	List of uncorrectable fatal errors seen and reported by this
		PCI device using ERR_FATAL. Note that since multiple errors may
		be reported using a single ERR_FATAL message, thus
		TOTAL_ERR_FATAL at the end of the file may not match the actual
		total of all the errors in the file. Sample output::

		    localhost /sys/devices/pci0000:00/0000:00:1c.0 # cat aer_dev_fatal
		    Undefined 0
		    Data Link Protocol 0
		    Surprise Down Error 0
		    Poisoned TLP 0
		    Flow Control Protocol 0
		    Completion Timeout 0
		    Completer Abort 0
		    Unexpected Completion 0
		    Receiver Overflow 0
		    Malformed TLP 0
		    ECRC 0
		    Unsupported Request 0
		    ACS Violation 0
		    Uncorrectable Internal Error 0
		    MC Blocked TLP 0
		    AtomicOp Egress Blocked 0
		    TLP Prefix Blocked Error 0
		    TOTAL_ERR_FATAL 0

What:		/sys/bus/pci/devices/<dev>/aer_dev_nonfatal
Date:		July 2018
KernelVersion: 4.19.0
Contact:	linux-pci@vger.kernel.org, rajatja@google.com
Description:	List of uncorrectable nonfatal errors seen and reported by this
		PCI device using ERR_NONFATAL. Note that since multiple errors
		may be reported using a single ERR_FATAL message, thus
		TOTAL_ERR_NONFATAL at the end of the file may not match the
		actual total of all the errors in the file. Sample output::

		    localhost /sys/devices/pci0000:00/0000:00:1c.0 # cat aer_dev_nonfatal
		    Undefined 0
		    Data Link Protocol 0
		    Surprise Down Error 0
		    Poisoned TLP 0
		    Flow Control Protocol 0
		    Completion Timeout 0
		    Completer Abort 0
		    Unexpected Completion 0
		    Receiver Overflow 0
		    Malformed TLP 0
		    ECRC 0
		    Unsupported Request 0
		    ACS Violation 0
		    Uncorrectable Internal Error 0
		    MC Blocked TLP 0
		    AtomicOp Egress Blocked 0
		    TLP Prefix Blocked Error 0
		    TOTAL_ERR_NONFATAL 0

PCIe Rootport AER statistics
----------------------------

These attributes show up under only the rootports (or root complex event
collectors) that are AER capable. These indicate the number of error messages as
"reported to" the rootport. Please note that the rootports also transmit
(internally) the ERR_* messages for errors seen by the internal rootport PCI
device, so these counters include them and are thus cumulative of all the error
messages on the PCI hierarchy originating at that root port.

What:		/sys/bus/pci/devices/<dev>/aer_stats/aer_rootport_total_err_cor
Date:		July 2018
KernelVersion: 4.19.0
Contact:	linux-pci@vger.kernel.org, rajatja@google.com
Description:	Total number of ERR_COR messages reported to rootport.

What:	    /sys/bus/pci/devices/<dev>/aer_stats/aer_rootport_total_err_fatal
Date:		July 2018
KernelVersion: 4.19.0
Contact:	linux-pci@vger.kernel.org, rajatja@google.com
Description:	Total number of ERR_FATAL messages reported to rootport.

What:	    /sys/bus/pci/devices/<dev>/aer_stats/aer_rootport_total_err_nonfatal
Date:		July 2018
KernelVersion: 4.19.0
Contact:	linux-pci@vger.kernel.org, rajatja@google.com
Description:	Total number of ERR_NONFATAL messages reported to rootport.

repo_name: angery/linux


code:
What:		/sys/devices/pci0000:00/<dev>/fw_version
Date:		September 2020
Contact:	Cezary Rojewski <cezary.rojewski@intel.com>
Description:
		Version of AudioDSP firmware ASoC catpt driver is
		communicating with.

		Format: %d.%d.%d.%d, type:major:minor:build.

What:		/sys/devices/pci0000:00/<dev>/fw_info
Date:		September 2020
Contact:	Cezary Rojewski <cezary.rojewski@intel.com>
Description:
		Detailed AudioDSP firmware build information including
		build hash and log-providers hash. This information is
		obtained during initial handshake with firmware.
		Format: %s.


code:
What:		/sys/bus/pci/devices/<dev>/ccissX/cXdY/model
Date:		March 2009
KernelVersion: 2.6.30
Contact:	iss_storagedev@hp.com
Description:	Displays the SCSI INQUIRY page 0 model for logical drive
		Y of controller X.

What:		/sys/bus/pci/devices/<dev>/ccissX/cXdY/rev
Date:		March 2009
KernelVersion: 2.6.30
Contact:	iss_storagedev@hp.com
Description:	Displays the SCSI INQUIRY page 0 revision for logical
		drive Y of controller X.

What:		/sys/bus/pci/devices/<dev>/ccissX/cXdY/unique_id
Date:		March 2009
KernelVersion: 2.6.30
Contact:	iss_storagedev@hp.com
Description:	Displays the SCSI INQUIRY page 83 serial number for logical
		drive Y of controller X.

What:		/sys/bus/pci/devices/<dev>/ccissX/cXdY/vendor
Date:		March 2009
KernelVersion: 2.6.30
Contact:	iss_storagedev@hp.com
Description:	Displays the SCSI INQUIRY page 0 vendor for logical drive
		Y of controller X.

What:		/sys/bus/pci/devices/<dev>/ccissX/cXdY/block:cciss!cXdY
Date:		March 2009
KernelVersion: 2.6.30
Contact:	iss_storagedev@hp.com
Description:	A symbolic link to /sys/block/cciss!cXdY

What:		/sys/bus/pci/devices/<dev>/ccissX/rescan
Date:		August 2009
KernelVersion:	2.6.31
Contact:	iss_storagedev@hp.com
Description:	Kicks of a rescan of the controller to discover logical
		drive topology changes.

What:		/sys/bus/pci/devices/<dev>/ccissX/cXdY/lunid
Date:		August 2009
KernelVersion: 2.6.31
Contact:	iss_storagedev@hp.com
Description:	Displays the 8-byte LUN ID used to address logical
		drive Y of controller X.

What:		/sys/bus/pci/devices/<dev>/ccissX/cXdY/raid_level
Date:		August 2009
KernelVersion: 2.6.31
Contact:	iss_storagedev@hp.com
Description:	Displays the RAID level of logical drive Y of
		controller X.

What:		/sys/bus/pci/devices/<dev>/ccissX/cXdY/usage_count
Date:		August 2009
KernelVersion: 2.6.31
Contact:	iss_storagedev@hp.com
Description:	Displays the usage count (number of opens) of logical drive Y
		of controller X.

What:		/sys/bus/pci/devices/<dev>/ccissX/resettable
Date:		February 2011
KernelVersion:	2.6.38
Contact:	iss_storagedev@hp.com
Description:	Value of 1 indicates the controller can honor the reset_devices
		kernel parameter.  Value of 0 indicates reset_devices cannot be
		honored.  This is to allow, for example, kexec tools to be able
		to warn the user if they designate an unresettable device as
		a dump device, as kdump requires resetting the device in order
		to work reliably.

What:		/sys/bus/pci/devices/<dev>/ccissX/transport_mode
Date:		July 2011
KernelVersion:	3.0
Contact:	iss_storagedev@hp.com
Description:	Value of "simple" indicates that the controller has been placed
		in "simple mode". Value of "performant" indicates that the
		controller has been placed in "performant mode".


code:
What:		/sys/devices/pci0000:00/*/QEMU0001:00/capability for MMIO
		/sys/bus/pci/drivers/pvpanic-pci/0000:00:0*.0/capability for PCI
Date:		Jan 2021
Contact:	zhenwei pi <pizhenwei@bytedance.com>
Description:
		Read-only attribute. Capabilities of pvpanic device which
		are supported by QEMU.

		Format: %x.

		Detailed bit definition refers to section <Bit Definition>
		from pvpanic device specification:
		https://git.qemu.org/?p=qemu.git;a=blob_plain;f=docs/specs/pvpanic.txt

What:		/sys/devices/pci0000:00/*/QEMU0001:00/events
		/sys/bus/pci/drivers/pvpanic-pci/0000:00:0*.0/events for PCI
Date:		Jan 2021
Contact:	zhenwei pi <pizhenwei@bytedance.com>
Description:
		RW attribute. Set/get which features in-use. This attribute
		is used to enable/disable feature(s) of pvpanic device.
		Notice that this value should be a subset of capability.

		Format: %x.

		Also refer to pvpanic device specification.


code:
What:		/sys/bus/pci/drivers/ehci_hcd/.../companion
		/sys/bus/usb/devices/usbN/../companion
Date:		January 2007
KernelVersion:	2.6.21
Contact:	Alan Stern <stern@rowland.harvard.edu>
Description:
		PCI-based EHCI USB controllers (i.e., high-speed USB-2.0
		controllers) are often implemented along with a set of
		"companion" full/low-speed USB-1.1 controllers.  When a
		high-speed device is plugged in, the connection is routed
		to the EHCI controller; when a full- or low-speed device
		is plugged in, the connection is routed to the companion
		controller.

		Sometimes you want to force a high-speed device to connect
		at full speed, which can be accomplished by forcing the
		connection to be routed to the companion controller.
		That's what this file does.  Writing a port number to the
		file causes connections on that port to be routed to the
		companion controller, and writing the negative of a port
		number returns the port to normal operation.

		For example: To force the high-speed device attached to
		port 4 on bus 2 to run at full speed::

			echo 4 >/sys/bus/usb/devices/usb2/../companion

		To return the port to high-speed operation::

			echo -4 >/sys/bus/usb/devices/usb2/../companion

		Reading the file gives the list of ports currently forced
		to the companion controller.

		Note: Some EHCI controllers do not have companions; they
		may contain an internal "transaction translator" or they
		may be attached directly to a "rate-matching hub".  This
		mechanism will not work with such controllers.  Also, it
		cannot be used to force a port on a high-speed hub to
		connect at full speed.

		Note: When this file was first added, it appeared in a
		different sysfs directory.  The location given above is
		correct for 2.6.35 (and probably several earlier kernel
		versions as well).


code:
What:		/sys/bus/pci/drivers/janz-cmodio/.../modulbus_number
Date:		May 2010
KernelVersion:	2.6.35
Contact:	Ira W. Snyder <ira.snyder@gmail.com>
Description:
		Value representing the HEX switch S2 of the janz carrier board CMOD-IO or CAN-PCI2

		Read-only: value of the configuration switch (0..15)


code:
What:		/sys/bus/pci/drivers/xhci_hcd/.../dbc
Date:		June 2017
Contact:	Lu Baolu <baolu.lu@linux.intel.com>
Description:
		xHCI compatible USB host controllers (i.e. super-speed
		USB3 controllers) are often implemented with the Debug
		Capability (DbC). It can present a debug device which
		is fully compliant with the USB framework and provides
		the equivalent of a very high performance full-duplex
		serial link for debug purpose.

		The DbC debug device shares a root port with xHCI host.
		When the DbC is enabled, the root port will be assigned
		to the Debug Capability. Otherwise, it will be assigned
		to xHCI.

		Writing "enable" to this attribute will enable the DbC
		functionality and the shared root port will be assigned
		to the DbC device. Writing "disable" to this attribute
		will disable the DbC functionality and the shared root
		port will roll back to the xHCI.

		Reading this attribute gives the state of the DbC. It
		can be one of the following states: disabled, enabled,
		initialized, connected, configured and stalled.


code:
What:		/sys/bus/peci/rescan
Date:		July 2021
KernelVersion:	5.18
Contact:	Iwona Winiarska <iwona.winiarska@intel.com>
Description:
		Writing a non-zero value to this attribute will
		initiate scan for PECI devices on all PECI controllers
		in the system.

What:		/sys/bus/peci/devices/<controller_id>-<device_addr>/remove
Date:		July 2021
KernelVersion:	5.18
Contact:	Iwona Winiarska <iwona.winiarska@intel.com>
Description:
		Writing a non-zero value to this attribute will
		remove the PECI device and any of its children.


code:
What:		/sys/bus/platform/devices/.../driver_override
Date:		April 2014
Contact:	Kim Phillips <kim.phillips@freescale.com>
Description:
		This file allows the driver for a device to be specified which
		will override standard OF, ACPI, ID table, and name matching.
		When specified, only a driver with a name matching the value
		written to driver_override will have an opportunity to bind
		to the device.  The override is specified by writing a string
		to the driver_override file (echo vfio-platform > \
		driver_override) and may be cleared with an empty string
		(echo > driver_override).  This returns the device to standard
		matching rules binding.  Writing to driver_override does not
		automatically unbind the device from its current driver or make
		any attempt to automatically load the specified driver.  If no
		driver with a matching name is currently loaded in the kernel,
		the device will not bind to any driver.  This also allows
		devices to opt-out of driver binding using a driver_override
		name such as "none".  Only a single driver may be specified in
		the override, there is no support for parsing delimiters.

What:		/sys/bus/platform/devices/.../numa_node
Date:		June 2020
Contact:	Barry Song <song.bao.hua@hisilicon.com>
Description:
		This file contains the NUMA node to which the platform device
		is attached. It won't be visible if the node is unknown. The
		value comes from an ACPI _PXM method or a similar firmware
		source. Initial users for this file would be devices like
		arm smmu which are populated by arm64 acpi_iort.

What:		/sys/bus/platform/devices/.../msi_irqs/
Date:		August 2021
Contact:	Barry Song <song.bao.hua@hisilicon.com>
Description:
		The /sys/devices/.../msi_irqs directory contains a variable set
		of files, with each file being named after a corresponding msi
		irq vector allocated to that device.

What:		/sys/bus/platform/devices/.../msi_irqs/<N>
Date:		August 2021
Contact:	Barry Song <song.bao.hua@hisilicon.com>
Description:
		This attribute will show "msi" if <N> is a valid msi irq

What:		/sys/bus/platform/devices/.../modalias
Description:
		Same as MODALIAS in the uevent at device creation.

		A platform device that it is exposed via devicetree uses:

			- of:N`of node name`T`type`

		Other platform devices use, instead:

			- platform:`driver name`


code:
What:		/sys/bus/platform/devices/occ-hwmon.X/ffdc
KernelVersion:	5.15
Contact:	eajames@linux.ibm.com
Description:
		Contains the First Failure Data Capture from the SBEFIFO
		hardware, if there is any from a previous transfer. Otherwise,
		the file is empty. The data is cleared when it's been
		completely read by a user. As the name suggests, only the data
		from the first error is saved, until it's cleared upon read. The OCC hwmon driver, running on
		a Baseboard Management Controller (BMC), communicates with
		POWER9 and up processors over the Self-Boot Engine (SBE) FIFO.
		In many error conditions, the SBEFIFO will return error data
		indicating the type of error and system state, etc.


code:
What:		/sys/bus/platform/devices/<dev>/always_powered_in_suspend
Date:		June 2022
KernelVersion:	5.20
Contact:	Matthias Kaehlcke <matthias@kaehlcke.net>
		linux-usb@vger.kernel.org
Description:
		(RW) Controls whether the USB hub remains always powered
		during system suspend or not.


code:
What:		/sys/bus/rapidio/devices/<nn>:<d>:<iiii>
Description:
		For each RapidIO device, the RapidIO subsystem creates files in
		an individual subdirectory with the following name format of
		device_name "nn:d:iiii", where:

		====   ========================================================
		nn     two-digit hexadecimal ID of RapidIO network where the
		       device resides
		d      device type: 'e' - for endpoint or 's' - for switch
		iiii   four-digit device destID for endpoints, or switchID for
		       switches
		====   ========================================================

		For example, below is a list of device directories that
		represents a typical RapidIO network with one switch, one host,
		and two agent endpoints, as it is seen by the enumerating host
		(with destID = 1)::

		  /sys/bus/rapidio/devices/00:e:0000
		  /sys/bus/rapidio/devices/00:e:0002
		  /sys/bus/rapidio/devices/00:s:0001

		NOTE:
		  An enumerating or discovering endpoint does not create a
		  sysfs entry for itself, this is why an endpoint with destID=1
		  is not shown in the list.

Attributes Common for All RapidIO Devices
-----------------------------------------

What:		/sys/bus/rapidio/devices/<nn>:<d>:<iiii>/did
Date:		Nov, 2005
KernelVersion:	v2.6.15
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) returns the device identifier

What:		/sys/bus/rapidio/devices/<nn>:<d>:<iiii>/vid
Date:		Nov, 2005
KernelVersion:	v2.6.15
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) returns the device vendor identifier

What:		/sys/bus/rapidio/devices/<nn>:<d>:<iiii>/device_rev
Date:		Nov, 2005
KernelVersion:	v2.6.15
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) returns the device revision level

What:		/sys/bus/rapidio/devices/<nn>:<d>:<iiii>/asm_did
Date:		Nov, 2005
KernelVersion:	v2.6.15
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) returns identifier for the assembly containing the device

What:		/sys/bus/rapidio/devices/<nn>:<d>:<iiii>/asm_rev
Date:		Nov, 2005
KernelVersion:	v2.6.15
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) returns revision level of the assembly containing the
		device

What:		/sys/bus/rapidio/devices/<nn>:<d>:<iiii>/asm_vid
Date:		Nov, 2005
KernelVersion:	v2.6.15
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) returns vendor identifier of the assembly containing the
		device

What:		/sys/bus/rapidio/devices/<nn>:<d>:<iiii>/destid
Date:		Mar, 2011
KernelVersion:	v2.6.3
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) returns device destination ID assigned by the enumeration
		routine

What:		/sys/bus/rapidio/devices/<nn>:<d>:<iiii>/lprev
Date:		Mar, 2011
KernelVersion:	v2.6.39
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) returns name of previous device (switch) on the path to the
		device that that owns this attribute

What:		/sys/bus/rapidio/devices/<nn>:<d>:<iiii>/modalias
Date:		Jul, 2013
KernelVersion:	v3.11
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) returns the device modalias

What:		/sys/bus/rapidio/devices/<nn>:<d>:<iiii>/config
Date:		Nov, 2005
KernelVersion:	v2.6.15
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RW) Binary attribute to read from and write to the device
		configuration registers using the RapidIO maintenance
		transactions. This attribute is similar in behaviour to the
		"config" attribute of PCI devices and provides an access to the
		RapidIO device registers using standard file read and write
		operations.

RapidIO Switch Device Attributes
--------------------------------

RapidIO switches have additional attributes in sysfs. RapidIO subsystem supports
common and device-specific sysfs attributes for switches. Because switches are
integrated into the RapidIO subsystem, it offers a method to create
device-specific sysfs attributes by specifying a callback function that may be
set by the switch initialization routine during enumeration or discovery
process.

What:		/sys/bus/rapidio/devices/<nn>:<s>:<iiii>/routes
Date:		Nov, 2005
KernelVersion:	v2.6.15
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) reports switch routing information in "destID port" format.
		This attribute reports only valid routing table entries, one
		line for each entry.

What:		/sys/bus/rapidio/devices/<nn>:<s>:<iiii>/destid
Date:		Mar, 2011
KernelVersion:	v2.6.3
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) device destination ID of the associated device that defines
		a route to the switch

What:		/sys/bus/rapidio/devices/<nn>:<s>:<iiii>/hopcount
Date:		Mar, 2011
KernelVersion:	v2.6.39
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) number of hops on the path to the switch

What:		/sys/bus/rapidio/devices/<nn>:<s>:<iiii>/lnext
Date:		Mar, 2011
KernelVersion:	v2.6.39
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) returns names of devices linked to the switch except one of
		a device linked to the ingress port (reported as "lprev"). This
		is an array names with number of lines equal to number of ports
		in switch. If a switch port has no attached device, returns
		"null" instead of a device name.

Device-specific Switch Attributes
---------------------------------

IDT_GEN2-

What:		/sys/bus/rapidio/devices/<nn>:<s>:<iiii>/errlog
Date:		Oct, 2010
KernelVersion:	v2.6.37
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(RO) reads contents of device error log until it is empty.

RapidIO Bus Attributes
----------------------

What:		/sys/bus/rapidio/scan
Date:		May, 2013
KernelVersion:	v3.11
Contact:	Matt Porter <mporter@kernel.crashing.org>,
		Alexandre Bounine <alexandre.bounine@idt.com>
Description:
		(WO) Allows to trigger enumeration discovery process from user
		space. To initiate an enumeration or discovery process on
		specific mport device, a user needs to write mport_ID (not
		RapidIO destination ID) into this file. The mport_ID is a
		sequential number (0 ...  RIO_MAX_MPORTS) assigned to the mport
		device. For example, for a machine with a single RapidIO
		controller, mport_ID for that controller always will be 0. To
		initiate RapidIO enumeration/discovery on all available mports a
		user must write '-1' (or RIO_MPORT_ANY) into this attribute
		file.


code:
What:		/sys/bus/rbd/add
Date:		Oct, 2010
KernelVersion:	v2.6.37
Contact:	Sage Weil <sage@newdream.net>
Description:
		(WO) Add rbd block device.

		Usage: <mon ip addr> <options> <pool name> <rbd image name> [<snap name>]

		Example::

		 $ echo "192.168.0.1 name=admin rbd foo" > /sys/bus/rbd/add

		The snapshot name can be "-" or omitted to map the image
		read/write. A <dev-id> will be assigned for any registered block
		device. If snapshot is used, it will be mapped read-only.

What:		/sys/bus/rbd/remove
Date:		Oct, 2010
KernelVersion:	v2.6.37
Contact:	Sage Weil <sage@newdream.net>
Description:
		(WO) Remove rbd block device.

		Usage: <dev-id> [force]

		Example::

		 $ echo 2 > /sys/bus/rbd/remove

		Optional "force" argument which when passed will wait for
		running requests and then unmap the image. Requests sent to the
		driver after initiating the removal will be failed. (August
		2016, since 4.9.)

What:		/sys/bus/rbd/add_single_major
Date:		Dec, 2013
KernelVersion:	v3.14
Contact:	Sage Weil <sage@newdream.net>
Description:
		(WO) Available only if rbd module is inserted with single_major
		parameter set to true.

		Usage is the same as for /sys/bus/rbd/add. If present, this
		should be used instead of the latter: any attempts to use
		/sys/bus/rbd/add if /sys/bus/rbd/add_single_major is available
		will fail for backwards compatibility reasons.

What:		/sys/bus/rbd/remove_single_major
Date:		Dec, 2013
KernelVersion:	v3.14
Contact:	Sage Weil <sage@newdream.net>
Description:
		(WO) Available only if rbd module is inserted with single_major
		parameter set to true.

		Usage is the same as for /sys/bus/rbd/remove. If present, this
		should be used instead of the latter: any attempts to use
		/sys/bus/rbd/remove if /sys/bus/rbd/remove_single_major is
		available will fail for backwards compatibility reasons.

What:		/sys/bus/rbd/supported_features
Date:		Mar, 2017
KernelVersion:	v4.11
Contact:	Sage Weil <sage@newdream.net>
Description:
		(RO) Displays the features supported by the rbd module so that
		userspace can generate meaningful error messages and spell out
		unsupported features that need to be disabled.

What:		/sys/bus/rbd/devices/<dev-id>/size
What:		/sys/bus/rbd/devices/<dev-id>/major
What:		/sys/bus/rbd/devices/<dev-id>/client_id
What:		/sys/bus/rbd/devices/<dev-id>/pool
What:		/sys/bus/rbd/devices/<dev-id>/name
What:		/sys/bus/rbd/devices/<dev-id>/refresh
What:		/sys/bus/rbd/devices/<dev-id>/current_snap
Date:		Oct, 2010
KernelVersion:	v2.6.37
Contact:	Sage Weil <sage@newdream.net>
Description:

		==============	================================================
		size		(RO) The size (in bytes) of the mapped block
				device.

		major		(RO) The block device major number.

		client_id	(RO) The ceph unique client id that was assigned
				for this specific session.

		pool		(RO) The name of the storage pool where this rbd
				image resides. An rbd image name is unique
				within its pool.

		name		(RO) The name of the rbd image.

		refresh		(WO) Writing to this file will reread the image
				header data and set all relevant data structures
				accordingly.

		current_snap	(RO) The current snapshot for which the device
				is mapped.
		==============	================================================

What:		/sys/bus/rbd/devices/<dev-id>/pool_id
Date:		Jul, 2012
KernelVersion:	v3.6
Contact:	Sage Weil <sage@newdream.net>
Description:
		(RO) The unique identifier for the rbd image's pool. This is a
		permanent attribute of the pool. A pool's id will never change.

What:		/sys/bus/rbd/devices/<dev-id>/image_id
What:		/sys/bus/rbd/devices/<dev-id>/features
Date:		Oct, 2012
KernelVersion:	v3.7
Contact:	Sage Weil <sage@newdream.net>
Description:
		=========	===============================================
		image_id	(RO) The unique id for the rbd image. (For rbd
				image format 1 this is empty.)

		features	(RO) A hexadecimal encoding of the feature bits
				for this image.
		=========	===============================================

What:		/sys/bus/rbd/devices/<dev-id>/parent
Date:		Nov, 2012
KernelVersion:	v3.8
Contact:	Sage Weil <sage@newdream.net>
Description:
		(RO) Information identifying the chain of parent images in a
		layered rbd image. Entries are separated by empty lines.

What:		/sys/bus/rbd/devices/<dev-id>/minor
Date:		Dec, 2013
KernelVersion:	v3.14
Contact:	Sage Weil <sage@newdream.net>
Description:
		(RO) The block device minor number.

What:		/sys/bus/rbd/devices/<dev-id>/snap_id
What:		/sys/bus/rbd/devices/<dev-id>/config_info
What:		/sys/bus/rbd/devices/<dev-id>/cluster_fsid
What:		/sys/bus/rbd/devices/<dev-id>/client_addr
Date:		Aug, 2016
KernelVersion:	v4.9
Contact:	Sage Weil <sage@newdream.net>
Description:
		============	================================================
		snap_id		(RO) The current snapshot's id.

		config_info	(RO) The string written into
				/sys/bus/rbd/add{,_single_major}.

		cluster_fsid	(RO) The ceph cluster UUID.

		client_addr	(RO) The ceph unique client
				entity_addr_t (address + nonce). The format is
				<address>:<port>/<nonce>: '1.2.3.4:1234/5678' or
				'[1:2:3:4:5:6:7:8]:1234/5678'.
		============	================================================

path: Documentation/ABI/testing/sysfs-bus-rbd


code:
What:		/sys/bus/rpmsg/devices/.../name
Date:		June 2011
KernelVersion:	3.3
Contact:	Ohad Ben-Cohen <ohad@wizery.com>
Description:
		Every rpmsg device is a communication channel with a remote
		processor. Channels are identified with a (textual) name,
		which is maximum 32 bytes long (defined as RPMSG_NAME_SIZE in
		rpmsg.h).

		This sysfs entry contains the name of this channel.

What:		/sys/bus/rpmsg/devices/.../src
Date:		June 2011
KernelVersion:	3.3
Contact:	Ohad Ben-Cohen <ohad@wizery.com>
Description:
		Every rpmsg device is a communication channel with a remote
		processor. Channels have a local ("source") rpmsg address,
		and remote ("destination") rpmsg address. When an entity
		starts listening on one end of a channel, it assigns it with
		a unique rpmsg address (a 32 bits integer). This way when
		inbound messages arrive to this address, the rpmsg core
		dispatches them to the listening entity (a kernel driver).

		This sysfs entry contains the src (local) rpmsg address
		of this channel. If it contains 0xffffffff, then an address
		wasn't assigned (can happen if no driver exists for this
		channel).

What:		/sys/bus/rpmsg/devices/.../dst
Date:		June 2011
KernelVersion:	3.3
Contact:	Ohad Ben-Cohen <ohad@wizery.com>
Description:
		Every rpmsg device is a communication channel with a remote
		processor. Channels have a local ("source") rpmsg address,
		and remote ("destination") rpmsg address. When an entity
		starts listening on one end of a channel, it assigns it with
		a unique rpmsg address (a 32 bits integer). This way when
		inbound messages arrive to this address, the rpmsg core
		dispatches them to the listening entity.

		This sysfs entry contains the dst (remote) rpmsg address
		of this channel. If it contains 0xffffffff, then an address
		wasn't assigned (can happen if the kernel driver that
		is attached to this channel is exposing a service to the
		remote processor. This make it a local rpmsg server,
		and it is listening for inbound messages that may be sent
		from any remote rpmsg client; it is not bound to a single
		remote entity).

What:		/sys/bus/rpmsg/devices/.../announce
Date:		June 2011
KernelVersion:	3.3
Contact:	Ohad Ben-Cohen <ohad@wizery.com>
Description:
		Every rpmsg device is a communication channel with a remote
		processor. Channels are identified by a textual name (see
		/sys/bus/rpmsg/devices/.../name above) and have a local
		("source") rpmsg address, and remote ("destination") rpmsg
		address.

		A channel is first created when an entity, whether local
		or remote, starts listening on it for messages (and is thus
		called an rpmsg server).

		When that happens, a "name service" announcement is sent
		to the other processor, in order to let it know about the
		creation of the channel (this way remote clients know they
		can start sending messages).

		This sysfs entry tells us whether the channel is a local
		server channel that is announced (values are either
		true or false).

What:		/sys/bus/rpmsg/devices/.../driver_override
Date:		April 2018
KernelVersion:	4.18
Contact:	Bjorn Andersson <bjorn.andersson@linaro.org>
Description:
		Every rpmsg device is a communication channel with a remote
		processor. Channels are identified by a textual name (see
		/sys/bus/rpmsg/devices/.../name above) and have a local
		("source") rpmsg address, and remote ("destination") rpmsg
		address.

		The listening entity (or client) which communicates with a
		remote processor is referred as rpmsg driver. The rpmsg device
		and rpmsg driver are matched based on rpmsg device name and
		rpmsg driver ID table.

		This sysfs entry allows the rpmsg driver for a rpmsg device
		to be specified which will override standard OF, ID table
		and name matching.


code:
What:		/sys/bus/siox/devices/siox-X/active
KernelVersion:	4.16
Contact:	Thorsten Scherer <t.scherer@eckelmann.de>, Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Description:
		On reading represents the current state of the bus. If it
		contains a "0" the bus is stopped and connected devices are
		expected to not do anything because their watchdog triggered.
		When the file contains a "1" the bus is operated and periodically
		does a push-pull cycle to write and read data from the
		connected devices.

		When writing a "0" or "1" the bus moves to the described state.

What:		/sys/bus/siox/devices/siox-X/device_add
KernelVersion:	4.16
Contact:	Thorsten Scherer <t.scherer@eckelmann.de>, Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Description:
		Write-only file. Write

			<type> <inbytes> <outbytes> <statustype>

		to add a new device dynamically. <type> is the name that is used to match
		to a driver (similar to the platform bus). <inbytes> and <outbytes> define
		the length of the input and output shift register in bytes respectively.

		<statustype> defines the 4 bit device type that is check to identify connection
		problems.

		The new device is added to the end of the existing chain.

What:		/sys/bus/siox/devices/siox-X/device_remove
KernelVersion:	4.16
Contact:	Thorsten Scherer <t.scherer@eckelmann.de>, Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Description:
		Write-only file. A single write removes the last device in the siox chain.

What:		/sys/bus/siox/devices/siox-X/poll_interval_ns
KernelVersion:	4.16
Contact:	Thorsten Scherer <t.scherer@eckelmann.de>, Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Description:
		Defines the interval between two poll cycles in nano seconds.
		Note this is rounded to jiffies on writing. On reading the current value
		is returned.

What:		/sys/bus/siox/devices/siox-X-Y/connected
KernelVersion:	4.16
Contact:	Thorsten Scherer <t.scherer@eckelmann.de>, Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Description:
		Read-only value. "0" means the Yth device on siox bus X isn't "connected" i.e.
		communication with it is not ensured. "1" signals a working connection.

What:		/sys/bus/siox/devices/siox-X-Y/inbytes
KernelVersion:	4.16
Contact:	Thorsten Scherer <t.scherer@eckelmann.de>, Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Description:
		Read-only value reporting the inbytes value provided to siox-X/device_add

What:		/sys/bus/siox/devices/siox-X-Y/status_errors
KernelVersion:	4.16
Contact:	Thorsten Scherer <t.scherer@eckelmann.de>, Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Description:
		Counts the number of time intervals when the read status byte doesn't yield the
		expected value.

What:		/sys/bus/siox/devices/siox-X-Y/type
KernelVersion:	4.16
Contact:	Thorsten Scherer <t.scherer@eckelmann.de>, Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Description:
		Read-only value reporting the type value provided to siox-X/device_add.

What:		/sys/bus/siox/devices/siox-X-Y/watchdog
KernelVersion:	4.16
Contact:	Thorsten Scherer <t.scherer@eckelmann.de>, Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Description:
		Read-only value reporting if the watchdog of the siox device is
		active. "0" means the watchdog is not active and the device is expected to
		be operational. "1" means the watchdog keeps the device in reset.

What:		/sys/bus/siox/devices/siox-X-Y/watchdog_errors
KernelVersion:	4.16
Contact:	Thorsten Scherer <t.scherer@eckelmann.de>, Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Description:
		Read-only value reporting the number to time intervals when the
		watchdog was active.

What:		/sys/bus/siox/devices/siox-X-Y/outbytes
KernelVersion:	4.16
Contact:	Thorsten Scherer <t.scherer@eckelmann.de>, Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Description:
		Read-only value reporting the outbytes value provided to siox-X/device_add.


code:
What:		/sys/bus/soundwire/devices/sdw-master-<N>/revision
		/sys/bus/soundwire/devices/sdw-master-<N>/clk_stop_modes
		/sys/bus/soundwire/devices/sdw-master-<N>/clk_freq
		/sys/bus/soundwire/devices/sdw-master-<N>/clk_gears
		/sys/bus/soundwire/devices/sdw-master-<N>/default_col
		/sys/bus/soundwire/devices/sdw-master-<N>/default_frame_rate
		/sys/bus/soundwire/devices/sdw-master-<N>/default_row
		/sys/bus/soundwire/devices/sdw-master-<N>/dynamic_shape
		/sys/bus/soundwire/devices/sdw-master-<N>/err_threshold
		/sys/bus/soundwire/devices/sdw-master-<N>/max_clk_freq

Date:		April 2020

Contact:	Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
		Bard Liao <yung-chuan.liao@linux.intel.com>
		Vinod Koul <vkoul@kernel.org>

Description:	SoundWire Master-N DisCo properties.
		These properties are defined by MIPI DisCo Specification
		for SoundWire. They define various properties of the Master
		and are used by the bus to configure the Master. clk_stop_modes
		is a bitmask for simplifications and combines the
		clock-stop-mode0 and clock-stop-mode1 properties.


code:
What:		/sys/bus/soundwire/devices/sdw:.../status
		/sys/bus/soundwire/devices/sdw:.../device_number

Date:		September 2020

Contact:	Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
		Bard Liao <yung-chuan.liao@linux.intel.com>
		Vinod Koul <vkoul@kernel.org>

Description:	SoundWire Slave status

		These properties report the Slave status, e.g. if it
		is UNATTACHED or not, and in the latter case show the
		device_number. This status information is useful to
		detect devices exposed by platform firmware but not
		physically present on the bus, and conversely devices
		not exposed in platform firmware but enumerated.

What:		/sys/bus/soundwire/devices/sdw:.../dev-properties/mipi_revision
		/sys/bus/soundwire/devices/sdw:.../dev-properties/wake_capable
		/sys/bus/soundwire/devices/sdw:.../dev-properties/test_mode_capable
		/sys/bus/soundwire/devices/sdw:.../dev-properties/clk_stop_mode1
		/sys/bus/soundwire/devices/sdw:.../dev-properties/simple_clk_stop_capable
		/sys/bus/soundwire/devices/sdw:.../dev-properties/clk_stop_timeout
		/sys/bus/soundwire/devices/sdw:.../dev-properties/ch_prep_timeout
		/sys/bus/soundwire/devices/sdw:.../dev-properties/reset_behave
		/sys/bus/soundwire/devices/sdw:.../dev-properties/high_PHY_capable
		/sys/bus/soundwire/devices/sdw:.../dev-properties/paging_support
		/sys/bus/soundwire/devices/sdw:.../dev-properties/bank_delay_support
		/sys/bus/soundwire/devices/sdw:.../dev-properties/p15_behave
		/sys/bus/soundwire/devices/sdw:.../dev-properties/master_count
		/sys/bus/soundwire/devices/sdw:.../dev-properties/source_ports
		/sys/bus/soundwire/devices/sdw:.../dev-properties/sink_ports

Date:		May 2020

Contact:	Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
		Bard Liao <yung-chuan.liao@linux.intel.com>
		Vinod Koul <vkoul@kernel.org>

Description:	SoundWire Slave DisCo properties.
		These properties are defined by MIPI DisCo Specification
		for SoundWire. They define various properties of the
		SoundWire Slave and are used by the bus to configure
		the Slave

What:		/sys/bus/soundwire/devices/sdw:.../dp0/max_word
		/sys/bus/soundwire/devices/sdw:.../dp0/min_word
		/sys/bus/soundwire/devices/sdw:.../dp0/words
		/sys/bus/soundwire/devices/sdw:.../dp0/BRA_flow_controlled
		/sys/bus/soundwire/devices/sdw:.../dp0/simple_ch_prep_sm
		/sys/bus/soundwire/devices/sdw:.../dp0/imp_def_interrupts

Date:		May 2020

Contact:	Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
		Bard Liao <yung-chuan.liao@linux.intel.com>
		Vinod Koul <vkoul@kernel.org>

Description:	SoundWire Slave Data Port-0 DisCo properties.
		These properties are defined by MIPI DisCo Specification
		for the SoundWire. They define various properties of the
		Data port 0 are used by the bus to configure the Data Port 0.

What:		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/max_word
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/min_word
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/words
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/type
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/max_grouping
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/simple_ch_prep_sm
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/ch_prep_timeout
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/imp_def_interrupts
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/min_ch
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/max_ch
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/channels
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/ch_combinations
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/max_async_buffer
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/block_pack_mode
		/sys/bus/soundwire/devices/sdw:.../dp<N>_src/port_encoding

		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/max_word
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/min_word
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/words
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/type
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/max_grouping
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/simple_ch_prep_sm
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/ch_prep_timeout
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/imp_def_interrupts
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/min_ch
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/max_ch
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/channels
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/ch_combinations
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/max_async_buffer
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/block_pack_mode
		/sys/bus/soundwire/devices/sdw:.../dp<N>_sink/port_encoding

Date:		May 2020

Contact:	Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
		Bard Liao <yung-chuan.liao@linux.intel.com>
		Vinod Koul <vkoul@kernel.org>

Description:	SoundWire Slave Data Source/Sink Port-N DisCo properties.
		These properties are defined by MIPI DisCo Specification
		for SoundWire. They define various properties of the
		Source/Sink Data port N and are used by the bus to configure
		the Data Port N.


code:
What:		/sys/bus/spi/devices/.../spi-nor/jedec_id
Date:		April 2021
KernelVersion:	5.14
Contact:	linux-mtd@lists.infradead.org
Description:	(RO) The JEDEC ID of the SPI NOR flash as reported by the
		flash device.

		The attribute is not present if the flash doesn't support
		the "Read JEDEC ID" command (9Fh). This is the case for
		non-JEDEC compliant flashes.

What:		/sys/bus/spi/devices/.../spi-nor/manufacturer
Date:		April 2021
KernelVersion:	5.14
Contact:	linux-mtd@lists.infradead.org
Description:	(RO) Manufacturer of the SPI NOR flash.

		The attribute is not present if the flash device isn't
		known to the kernel and is only probed by its SFDP
		tables.

What:		/sys/bus/spi/devices/.../spi-nor/partname
Date:		April 2021
KernelVersion:	5.14
Contact:	linux-mtd@lists.infradead.org
Description:	(RO) Part name of the SPI NOR flash.

What:		/sys/bus/spi/devices/.../spi-nor/sfdp
Date:		April 2021
KernelVersion:	5.14
Contact:	linux-mtd@lists.infradead.org
Description:	(RO) This attribute is only present if the SPI NOR flash
		device supports the "Read SFDP" command (5Ah).

		If present, it contains the complete SFDP (serial flash
		discoverable parameters) binary data of the flash.


code:
What:		/sys/bus/surface_aggregator/devices/01:0e:01:00:01/state
Date:		July 2022
KernelVersion:	5.20
Contact:	Maximilian Luz <luzmaximilian@gmail.com>
Description:
		This attribute returns a string with the current type-cover
		or device posture, as indicated by the embedded controller.
		Currently returned posture states are:

		- "disconnected": The type-cover has been disconnected.

		- "closed": The type-cover has been folded closed and lies on
		  top of the display.

		- "laptop": The type-cover is open and in laptop-mode, i.e.,
		  ready for normal use.

		- "folded-canvas": The type-cover has been folded back
		  part-ways, but does not lie flush with the back side of the
		  device. In general, this means that the kick-stand is used
		  and extended atop of the cover.

		- "folded-back": The type cover has been fully folded back and
		  lies flush with the back side of the device.

		- "<unknown>": The current state is unknown to the driver, for
		  example due to newer as-of-yet unsupported hardware.

		New states may be introduced with new hardware. Users therefore
		must not rely on this list of states being exhaustive and
		gracefully handle unknown states.

What:		/sys/bus/surface_aggregator/devices/01:26:01:00:01/state
Date:		July 2022
KernelVersion:	5.20
Contact:	Maximilian Luz <luzmaximilian@gmail.com>
Description:
		This attribute returns a string with the current device posture, as indicated by the embedded controller. Currently
		returned posture states are:

		- "closed": The lid of the device is closed.

		- "laptop": The lid of the device is opened and the device
		  operates as a normal laptop.

		- "slate": The screen covers the keyboard or has been flipped
		  back and the device operates mainly based on touch input.

		- "tablet": The device operates as tablet and exclusively
		  relies on touch input (or external peripherals).

		- "<unknown>": The current state is unknown to the driver, for
		  example due to newer as-of-yet unsupported hardware.

		New states may be introduced with new hardware. Users therefore
		must not rely on this list of states being exhaustive and
		gracefully handle unknown states.


code:
What:		/sys/bus/thunderbolt/devices/.../domainX/boot_acl
Date:		Jun 2018
KernelVersion:	4.17
Contact:	thunderbolt-software@lists.01.org
Description:	Holds a comma separated list of device unique_ids that
		are allowed to be connected automatically during system
		startup (e.g boot devices). The list always contains
		maximum supported number of unique_ids where unused
		entries are empty. This allows the userspace software
		to determine how many entries the controller supports.
		If there are multiple controllers, each controller has
		its own ACL list and size may be different between the
		controllers.

		System BIOS may have an option "Preboot ACL" or similar
		that needs to be selected before this list is taken into
		consideration.

		Software always updates a full list in each write.

		If a device is authorized automatically during boot its
		boot attribute is set to 1.

What:		/sys/bus/thunderbolt/devices/.../domainX/deauthorization
Date:		May 2021
KernelVersion:	5.12
Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
Description:	This attribute tells whether the system supports
		de-authorization of devices. Value of 1 means user can
		de-authorize PCIe tunnel by writing 0 to authorized
		attribute under each device.

What:		/sys/bus/thunderbolt/devices/.../domainX/iommu_dma_protection
Date:		Mar 2019
KernelVersion:	4.21
Contact:	thunderbolt-software@lists.01.org
Description:	This attribute tells whether the system uses IOMMU
		for DMA protection. Value of 1 means IOMMU is used 0 means
		it is not (DMA protection is solely based on Thunderbolt
		security levels).

What:		/sys/bus/thunderbolt/devices/.../domainX/security
Date:		Sep 2017
KernelVersion:	4.13
Contact:	thunderbolt-software@lists.01.org
Description:	This attribute holds current Thunderbolt security level
		set by the system BIOS. Possible values are:

		=======  ==================================================
		none     All devices are automatically authorized
		user     Devices are only authorized based on writing
		         appropriate value to the authorized attribute
		secure   Require devices that support secure connect at
			 minimum. User needs to authorize each device.
		dponly   Automatically tunnel Display port (and USB). No
			 PCIe tunnels are created.
		usbonly  Automatically tunnel USB controller of the
			 connected Thunderbolt dock (and Display Port). All
			 PCIe links downstream of the dock are removed.
		nopcie   USB4 system where PCIe tunneling is disabled from
			 the BIOS.
		=======  ==================================================

What:		/sys/bus/thunderbolt/devices/.../authorized
Date:		Sep 2017
KernelVersion:	4.13
Contact:	thunderbolt-software@lists.01.org
Description:	This attribute is used to authorize Thunderbolt devices
		after they have been connected. If the device is not
		authorized, no PCIe devices are available to the system.

		Contents of this attribute will be 0 when the device is not
		yet authorized.

		Possible values are supported:

		==  ===================================================
		0   The device will be de-authorized (only supported if
		    deauthorization attribute under domain contains 1)
		1   The device will be authorized and connected
		==  ===================================================

		When key attribute contains 32 byte hex string the possible
		values are:

		==  ========================================================
		0   The device will be de-authorized (only supported if
		    deauthorization attribute under domain contains 1)
		1   The 32 byte hex string is added to the device NVM and
		    the device is authorized.
		2   Send a challenge based on the 32 byte hex string. If the
		    challenge response from device is valid, the device is
		    authorized. In case of failure errno will be ENOKEY if
		    the device did not contain a key at all, and
		    EKEYREJECTED if the challenge response did not match.
		==  ========================================================

What:		/sys/bus/thunderbolt/devices/.../boot
Date:		Jun 2018
KernelVersion:	4.17
Contact:	thunderbolt-software@lists.01.org
Description:	This attribute contains 1 if Thunderbolt device was already
		authorized on boot and 0 otherwise.

What:		/sys/bus/thunderbolt/devices/.../generation
Date:		Jan 2020
KernelVersion:	5.5
Contact:	Christian Kellner <christian@kellner.me>
Description:	This attribute contains the generation of the Thunderbolt
		controller associated with the device. It will contain 4
		for USB4.

What:		/sys/bus/thunderbolt/devices/.../key
Date:		Sep 2017
KernelVersion:	4.13
Contact:	thunderbolt-software@lists.01.org
Description:	When a devices supports Thunderbolt secure connect it will
		have this attribute. Writing 32 byte hex string changes
		authorization to use the secure connection method instead.
		Writing an empty string clears the key and regular connection
		method can be used again.

What:		/sys/bus/thunderbolt/devices/.../device
Date:		Sep 2017
KernelVersion:	4.13
Contact:	thunderbolt-software@lists.01.org
Description:	This attribute contains id of this device extracted from
		the device DROM.

What:		/sys/bus/thunderbolt/devices/.../device_name
Date:		Sep 2017
KernelVersion:	4.13
Contact:	thunderbolt-software@lists.01.org
Description:	This attribute contains name of this device extracted from
		the device DROM.

What:		/sys/bus/thunderbolt/devices/.../maxhopid
Date:		Jul 2021
KernelVersion:	5.13
Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
Description:	Only set for XDomains. The maximum HopID the other host
		supports as its input HopID.

What:		/sys/bus/thunderbolt/devices/.../rx_speed
Date:		Jan 2020
KernelVersion:	5.5
Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
Description:	This attribute reports the device RX speed per lane.
		All RX lanes run at the same speed.

What:		/sys/bus/thunderbolt/devices/.../rx_lanes
Date:		Jan 2020
KernelVersion:	5.5
Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
Description:	This attribute reports number of RX lanes the device is
		using simultaneously through its upstream port.

What:		/sys/bus/thunderbolt/devices/.../tx_speed
Date:		Jan 2020
KernelVersion:	5.5
Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
Description:	This attribute reports the TX speed per lane.
		All TX lanes run at the same speed.

What:		/sys/bus/thunderbolt/devices/.../tx_lanes
Date:		Jan 2020
KernelVersion:	5.5
Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
Description:	This attribute reports number of TX lanes the device is
		using simultaneously through its upstream port.

What:		/sys/bus/thunderbolt/devices/.../vendor
Date:		Sep 2017
KernelVersion:	4.13
Contact:	thunderbolt-software@lists.01.org
Description:	This attribute contains vendor id of this device extracted
		from the device DROM.

What:		/sys/bus/thunderbolt/devices/.../vendor_name
Date:		Sep 2017
KernelVersion:	4.13
Contact:	thunderbolt-software@lists.01.org
Description:	This attribute contains vendor name of this device extracted
		from the device DROM.

What:		/sys/bus/thunderbolt/devices/.../unique_id
Date:		Sep 2017
KernelVersion:	4.13
Contact:	thunderbolt-software@lists.01.org
Description:	This attribute contains unique_id string of this device.
		This is either read from hardware registers (UUID on
		newer hardware) or based on UID from the device DROM.
		Can be used to uniquely identify particular device.

What:		/sys/bus/thunderbolt/devices/.../nvm_version
Date:		Sep 2017
KernelVersion:	4.13
Contact:	thunderbolt-software@lists.01.org
Description:	If the device has upgradeable firmware the version
		number is available here. Format: %x.%x, major.minor.
		If the device is in safe mode reading the file returns
		-ENODATA instead as the NVM version is not available.

What:		/sys/bus/thunderbolt/devices/.../nvm_authenticate
Date:		Sep 2017
KernelVersion:	4.13
Contact:	thunderbolt-software@lists.01.org
Description:	When new NVM image is written to the non-active NVM
		area (through non_activeX NVMem device), the
		authentication procedure is started by writing to
		this file.
		If everything goes well, the device is
		restarted with the new NVM firmware. If the image
		verification fails an error code is returned instead.

		This file will accept writing values "1", "2" or "3".

		- Writing "1" will flush the image to the storage
		  area and authenticate the image in one action.
		- Writing "2" will run some basic validation on the image
		  and flush it to the storage area.
		- Writing "3" will authenticate the image that is
		  currently written in the storage area. This is only
		  supported with USB4 devices and retimers.

		When read holds status of the last authentication
		operation if an error occurred during the process. This
		is directly the status value from the DMA configuration
		based mailbox before the device is power cycled. Writing
		0 here clears the status.

What:		/sys/bus/thunderbolt/devices/.../nvm_authenticate_on_disconnect
Date:		Oct 2020
KernelVersion:	v5.9
Contact:	Mario Limonciello <mario.limonciello@outlook.com>
Description:	For supported devices, automatically authenticate the new Thunderbolt
		image when the device is disconnected from the host system.

		This file will accept writing values "1" or "2"

		- Writing "1" will flush the image to the storage
		  area and prepare the device for authentication on disconnect.
		- Writing "2" will run some basic validation on the image
		  and flush it to the storage area.

What:		/sys/bus/thunderbolt/devices/<xdomain>.<service>/key
Date:		Jan 2018
KernelVersion:	4.15
Contact:	thunderbolt-software@lists.01.org
Description:	This contains name of the property directory the XDomain
		service exposes. This entry describes the protocol in
		question. Following directories are already reserved by
		the Apple XDomain specification:

		========  ===============================================
		network   IP/ethernet over Thunderbolt
		targetdm  Target disk mode protocol over Thunderbolt
		extdisp   External display mode protocol over Thunderbolt
		========  ===============================================

What:		/sys/bus/thunderbolt/devices/<xdomain>.<service>/modalias
Date:		Jan 2018
KernelVersion:	4.15
Contact:	thunderbolt-software@lists.01.org
Description:	Stores the same MODALIAS value emitted by uevent for
		the XDomain service. Format: tbtsvc:kSpNvNrN

What:		/sys/bus/thunderbolt/devices/<xdomain>.<service>/prtcid
Date:		Jan 2018
KernelVersion:	4.15
Contact:	thunderbolt-software@lists.01.org
Description:	This contains XDomain protocol identifier the XDomain
		service supports.

What:		/sys/bus/thunderbolt/devices/<xdomain>.<service>/prtcvers
Date:		Jan 2018
KernelVersion:	4.15
Contact:	thunderbolt-software@lists.01.org
Description:	This contains XDomain protocol version the XDomain
		service supports.

What:		/sys/bus/thunderbolt/devices/<xdomain>.<service>/prtcrevs
Date:		Jan 2018
KernelVersion:	4.15
Contact:	thunderbolt-software@lists.01.org
Description:	This contains XDomain software version the XDomain
		service supports.

What:		/sys/bus/thunderbolt/devices/<xdomain>.<service>/prtcstns
Date:		Jan 2018
KernelVersion:	4.15
Contact:	thunderbolt-software@lists.01.org
Description:	This contains XDomain service specific settings as
		bitmask. Format: %x

What:		/sys/bus/thunderbolt/devices/usb4_portX/connector
Date:		April 2022
Contact:	Heikki Krogerus <heikki.krogerus@linux.intel.com>
Description:
		Symlink to the USB Type-C connector. This link is only
		created when USB Type-C Connector Class is enabled,
		and only if the system firmware is capable of
		describing the connection between a port and its
		connector.

What:		/sys/bus/thunderbolt/devices/usb4_portX/link
Date:		Sep 2021
KernelVersion:	v5.14
Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
Description:	Returns the current link mode. Possible values are
		"usb4", "tbt" and "none".

What:		/sys/bus/thunderbolt/devices/usb4_portX/offline
Date:		Sep 2021
KernelVersion:	v5.14
Contact:	Rajmohan Mani <rajmohan.mani@intel.com>
Description:	Writing 1 to this attribute puts the USB4 port into
		offline mode. Only allowed when there is nothing
		connected to the port (link attribute returns "none").
		Once the port is in offline mode it does not receive any
		hotplug events. This is used to update NVM firmware of
		on-board retimers. Writing 0 puts the port back to
		online mode.

		This attribute is only visible if the platform supports
		powering on retimers when there is no cable connected.

What:		/sys/bus/thunderbolt/devices/usb4_portX/rescan
Date:		Sep 2021
KernelVersion:	v5.14
Contact:	Rajmohan Mani <rajmohan.mani@intel.com>
Description:	When the USB4 port is in offline mode writing 1 to this
		attribute forces rescan of the sideband for on-board
		retimers. Each retimer appear under the USB4 port as if
		the USB4 link was up. These retimers act in the same way
		as if the cable was connected so upgrading their NVM
		firmware can be done the usual way.

What:		/sys/bus/thunderbolt/devices/<device>:<port>.<index>/device
Date:		Oct 2020
KernelVersion:	v5.9
Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
Description:	Retimer device identifier read from the hardware.

What:		/sys/bus/thunderbolt/devices/<device>:<port>.<index>/nvm_authenticate
Date:		Oct 2020
KernelVersion:	v5.9
Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
Description:	When new NVM image is written to the non-active NVM
		area (through non_activeX NVMem device), the
		authentication procedure is started by writing 1 to
		this file. If everything goes well, the device is
		restarted with the new NVM firmware. If the image
		verification fails an error code is returned instead.

		When read holds status of the last authentication
		operation if an error occurred during the process.
		Format: %x.

What:		/sys/bus/thunderbolt/devices/<device>:<port>.<index>/nvm_version
Date:		Oct 2020
KernelVersion:	v5.9
Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
Description:	Holds retimer NVM version number. Format: %x.%x, major.minor.

What:		/sys/bus/thunderbolt/devices/<device>:<port>.<index>/vendor
Date:		Oct 2020
KernelVersion:	v5.9
Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
Description:	Retimer vendor identifier read from the hardware.


code:
What:		/sys/bus/typec/devices/.../active
Date:		July 2018
Contact:	Heikki Krogerus <heikki.krogerus@linux.intel.com>
Description:
		Shows if the mode is active or not. The attribute can be used
		for entering/exiting the mode. Entering/exiting modes is
		supported as synchronous operation so write(2) to the attribute
		does not return until the enter/exit mode operation has
		finished. The attribute is notified when the mode is
		entered/exited so poll(2) on the attribute wakes up.
		Entering/exiting a mode will also generate uevent KOBJ_CHANGE.

		Valid values are boolean.

What:		/sys/bus/typec/devices/.../description
Date:		July 2018
Contact:	Heikki Krogerus <heikki.krogerus@linux.intel.com>
Description:
		Shows description of the mode. The description is optional for
		the drivers, just like with the Billboard Devices.

What:		/sys/bus/typec/devices/.../mode
Date:		July 2018
Contact:	Heikki Krogerus <heikki.krogerus@linux.intel.com>
Description:
		The index number of the mode returned by Discover Modes USB
		Power Delivery command. Depending on the alternate mode, the
		mode index may be significant.

		With some alternate modes (SVIDs), the mode index is assigned
		for specific functionality in the specification for that
		alternate mode.

		With other alternate modes, the mode index values are not
		assigned, and can not be therefore used for identification. When
		the mode index is not assigned, identifying the alternate mode
		must be done with either mode VDO or the description.

What:		/sys/bus/typec/devices/.../svid
Date:		July 2018
Contact:	Heikki Krogerus <heikki.krogerus@linux.intel.com>
Description:
		The Standard or Vendor ID (SVID) assigned by USB-IF for this
		alternate mode.

What:		/sys/bus/typec/devices/.../vdo
Date:		July 2018
Contact:	Heikki Krogerus <heikki.krogerus@linux.intel.com>
Description:
		Shows the VDO in hexadecimal returned by Discover Modes command
		for this mode.


code:
What:           /sys/bus/umc/
Date:           July 2008
KernelVersion:  2.6.27
Contact:        David Vrabel <david.vrabel@csr.com>
Description:
                The Wireless Host Controller Interface (WHCI)
                specification describes a PCI-based device with
                multiple capabilities; the UWB Multi-interface
                Controller (UMC).

                The umc bus presents each of the individual
                capabilties as a device.

What:           /sys/bus/umc/devices/.../capability_id
Date:           July 2008
KernelVersion:  2.6.27
Contact:        David Vrabel <david.vrabel@csr.com>
Description:
                The ID of this capability, with 0 being the radio
                controller capability.

What:           /sys/bus/umc/devices/.../version
Date:           July 2008
KernelVersion:  2.6.27
Contact:        David Vrabel <david.vrabel@csr.com>
Description:
                The specification version this capability's hardware
                interface complies with.

path: Documentation/ABI/testing/sysfs-bus-umc