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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /Documentation/ABI/testing/sysfs-bus-usb
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb
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+What: /sys/bus/usb/devices/<INTERFACE>/authorized
+Date: August 2015
+Description:
+ This allows to authorize (1) or deauthorize (0)
+ individual interfaces instead a whole device
+ in contrast to the device authorization.
+ If a deauthorized interface will be authorized
+ so the driver probing must be triggered manually
+ by writing INTERFACE to /sys/bus/usb/drivers_probe
+ This allows to avoid side-effects with drivers
+ that need multiple interfaces.
+
+ A deauthorized interface cannot be probed or claimed.
+
+What: /sys/bus/usb/devices/usbX/interface_authorized_default
+Date: August 2015
+Description:
+ This is used as value that determines if interfaces
+ would be authorized by default.
+ The value can be 1 or 0. It's by default 1.
+
+What: /sys/bus/usb/device/.../authorized
+Date: July 2008
+KernelVersion: 2.6.26
+Contact: David Vrabel <david.vrabel@csr.com>
+Description:
+ Authorized devices are available for use by device
+ drivers, non-authorized one are not. By default, wired
+ USB devices are authorized.
+
+What: /sys/bus/usb/drivers/.../new_id
+Date: October 2011
+Contact: linux-usb@vger.kernel.org
+Description:
+ Writing a device ID to this file will attempt to
+ dynamically add a new device ID to a USB 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:
+ idVendor idProduct bInterfaceClass RefIdVendor RefIdProduct
+ The vendor ID and device ID fields are required, the
+ rest is optional. The `Ref*` tuple can be used to tell the
+ driver to use the same driver_data for the new device as
+ it is used for the reference device.
+ 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/usb/drivers/foo/new_id
+
+ Here add a new device (0458:7045) using driver_data from
+ an already supported device (0458:704c)::
+
+ # echo "0458 7045 0 0458 704c" > /sys/bus/usb/drivers/foo/new_id
+
+ Reading from this file will list all dynamically added
+ device IDs in the same format, with one entry per
+ line. For example::
+
+ # cat /sys/bus/usb/drivers/foo/new_id
+ 8086 10f5
+ dead beef 06
+ f00d cafe
+
+ The list will be truncated at PAGE_SIZE bytes due to
+ sysfs restrictions.
+
+What: /sys/bus/usb-serial/drivers/.../new_id
+Date: October 2011
+Contact: linux-usb@vger.kernel.org
+Description:
+ For serial USB drivers, this attribute appears under the
+ extra bus folder "usb-serial" in sysfs; apart from that
+ difference, all descriptions from the entry
+ "/sys/bus/usb/drivers/.../new_id" apply.
+
+What: /sys/bus/usb/drivers/.../remove_id
+Date: November 2009
+Contact: CHENG Renquan <rqcheng@smu.edu.sg>
+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:
+ idVendor idProduct. 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 "046d c315" > /sys/bus/usb/drivers/foo/remove_id
+
+ Reading from this file will list the dynamically added
+ device IDs, exactly like reading from the entry
+ "/sys/bus/usb/drivers/.../new_id"
+
+What: /sys/bus/usb/devices/.../power/usb2_hardware_lpm
+Date: September 2011
+Contact: Andiry Xu <andiry.xu@amd.com>
+Description:
+ If CONFIG_PM is set and a USB 2.0 lpm-capable device is plugged
+ in to a xHCI host which support link PM, it will perform a LPM
+ test; if the test is passed and host supports USB2 hardware LPM
+ (xHCI 1.0 feature), USB2 hardware LPM will be enabled for the
+ device and the USB device directory will contain a file named
+ power/usb2_hardware_lpm. The file holds a string value (enable
+ or disable) indicating whether or not USB2 hardware LPM is
+ enabled for the device. Developer can write y/Y/1 or n/N/0 to
+ the file to enable/disable the feature.
+
+What: /sys/bus/usb/devices/.../power/usb3_hardware_lpm_u1
+ /sys/bus/usb/devices/.../power/usb3_hardware_lpm_u2
+Date: November 2015
+Contact: Kevin Strasser <kevin.strasser@linux.intel.com>
+ Lu Baolu <baolu.lu@linux.intel.com>
+Description:
+ If CONFIG_PM is set and a USB 3.0 lpm-capable device is plugged
+ in to a xHCI host which supports link PM, it will check if U1
+ and U2 exit latencies have been set in the BOS descriptor; if
+ the check is passed and the host supports USB3 hardware LPM,
+ USB3 hardware LPM will be enabled for the device and the USB
+ device directory will contain two files named
+ power/usb3_hardware_lpm_u1 and power/usb3_hardware_lpm_u2. These
+ files hold a string value (enable or disable) indicating whether
+ or not USB3 hardware LPM U1 or U2 is enabled for the device.
+
+What: /sys/bus/usb/devices/.../ltm_capable
+Date: July 2012
+Contact: Sarah Sharp <sarah.a.sharp@linux.intel.com>
+Description:
+ USB 3.0 devices may optionally support Latency Tolerance
+ Messaging (LTM). They indicate their support by setting a bit
+ in the bmAttributes field of their SuperSpeed BOS descriptors.
+ If that bit is set for the device, ltm_capable will read "yes".
+ If the device doesn't support LTM, the file will read "no".
+ The file will be present for all speeds of USB devices, and will
+ always read "no" for USB 1.1 and USB 2.0 devices.
+
+What: /sys/bus/usb/devices/<INTERFACE>/wireless_status
+Date: February 2023
+Contact: Bastien Nocera <hadess@hadess.net>
+Description:
+ Some USB devices use a USB receiver dongle to communicate
+ wirelessly with their device using proprietary protocols. This
+ attribute allows user-space to know whether the device is
+ connected to its receiver dongle, and, for example, consider
+ the device to be absent when choosing whether to show the
+ device's battery, show a headset in a list of outputs, or show
+ an on-screen keyboard if the only wireless keyboard is
+ turned off.
+ This attribute is not to be used to replace protocol specific
+ statuses available in WWAN, WLAN/Wi-Fi, Bluetooth, etc.
+ If the device does not use a receiver dongle with a wireless
+ device, then this attribute will not exist.
+
+What: /sys/bus/usb/devices/.../<hub_interface>/port<X>
+Date: August 2012
+Contact: Lan Tianyu <tianyu.lan@intel.com>
+Description:
+ The /sys/bus/usb/devices/.../<hub_interface>/port<X>
+ is usb port device's sysfs directory.
+
+What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/connect_type
+Date: January 2013
+Contact: Lan Tianyu <tianyu.lan@intel.com>
+Description:
+ Some platforms provide usb port connect types through ACPI.
+ This attribute is to expose these information to user space.
+ The file will read "hotplug", "hardwired" and "not used" if the
+ information is available, and "unknown" otherwise.
+
+What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/location
+Date: October 2018
+Contact: Bjørn Mork <bjorn@mork.no>
+Description:
+ Some platforms provide usb port physical location through
+ firmware. This is used by the kernel to pair up logical ports
+ mapping to the same physical connector. The attribute exposes the
+ raw location value as a hex integer.
+
+
+What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/quirks
+Date: May 2018
+Contact: Nicolas Boichat <drinkcat@chromium.org>
+Description:
+ In some cases, we care about time-to-active for devices
+ connected on a specific port (e.g. non-standard USB port like
+ pogo pins), where the device to be connected is known in
+ advance, and behaves well according to the specification.
+ This attribute is a bit-field that controls the behavior of
+ a specific port:
+
+ - Bit 0 of this field selects the "old" enumeration scheme,
+ as it is considerably faster (it only causes one USB reset
+ instead of 2).
+
+ The old enumeration scheme can also be selected globally
+ using /sys/module/usbcore/parameters/old_scheme_first, but
+ it is often not desirable as the new scheme was introduced to
+ increase compatibility with more devices.
+ - Bit 1 reduces TRSTRCY to the 10 ms that are required by the
+ USB 2.0 specification, instead of the 50 ms that are normally
+ used to help make enumeration work better on some high speed
+ devices.
+
+What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/over_current_count
+Date: February 2018
+Contact: Richard Leitner <richard.leitner@skidata.com>
+Description:
+ Most hubs are able to detect over-current situations on their
+ ports and report them to the kernel. This attribute is to expose
+ the number of over-current situation occurred on a specific port
+ to user space. This file will contain an unsigned 32 bit value
+ which wraps to 0 after its maximum is reached. This file supports
+ poll() for monitoring changes to this value in user space.
+
+ Any time this value changes the corresponding hub device will send a
+ udev event with the following attributes::
+
+ OVER_CURRENT_PORT=/sys/bus/usb/devices/.../<hub_interface>/port<X>
+ OVER_CURRENT_COUNT=[current value of this sysfs attribute]
+
+What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/usb3_lpm_permit
+Date: November 2015
+Contact: Lu Baolu <baolu.lu@linux.intel.com>
+Description:
+ Some USB3.0 devices are not friendly to USB3 LPM. usb3_lpm_permit
+ attribute allows enabling/disabling usb3 lpm of a port. It takes
+ effect both before and after a usb device is enumerated. Supported
+ values are "0" if both u1 and u2 are NOT permitted, "u1" if only u1
+ is permitted, "u2" if only u2 is permitted, "u1_u2" if both u1 and
+ u2 are permitted.
+
+What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/connector
+Date: December 2021
+Contact: Heikki Krogerus <heikki.krogerus@linux.intel.com>
+Description:
+ Link to the USB Type-C connector when available. 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/usb/devices/.../<hub_interface>/port<X>/disable
+Date: June 2022
+Contact: Michael Grzeschik <m.grzeschik@pengutronix.de>
+Description:
+ This file controls the state of a USB port, including
+ Vbus power output (but only on hubs that support
+ power switching -- most hubs don't support it). If
+ a port is disabled, the port is unusable: Devices
+ attached to the port will not be detected, initialized,
+ or enumerated.
+
+What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/early_stop
+Date: Sep 2022
+Contact: Ray Chi <raychi@google.com>
+Description:
+ Some USB hosts have some watchdog mechanisms so that the device
+ may enter ramdump if it takes a long time during port initialization.
+ This attribute allows each port just has two attempts so that the
+ port initialization will be failed quickly. In addition, if a port
+ which is marked with early_stop has failed to initialize, it will ignore
+ all future connections until this attribute is clear.
+
+What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/state
+Date: June 2023
+Contact: Roy Luo <royluo@google.com>
+Description:
+ Indicates current state of the USB device attached to the port.
+ Valid states are: 'not-attached', 'attached', 'powered',
+ 'reconnecting', 'unauthenticated', 'default', 'addressed',
+ 'configured', and 'suspended'. This file supports poll() to
+ monitor the state change from user space.
+
+What: /sys/bus/usb/devices/.../power/usb2_lpm_l1_timeout
+Date: May 2013
+Contact: Mathias Nyman <mathias.nyman@linux.intel.com>
+Description:
+ USB 2.0 devices may support hardware link power management (LPM)
+ L1 sleep state. The usb2_lpm_l1_timeout attribute allows
+ tuning the timeout for L1 inactivity timer (LPM timer), e.g.
+ needed inactivity time before host requests the device to go to L1 sleep.
+ Useful for power management tuning.
+ Supported values are 0 - 65535 microseconds.
+
+What: /sys/bus/usb/devices/.../power/usb2_lpm_besl
+Date: May 2013
+Contact: Mathias Nyman <mathias.nyman@linux.intel.com>
+Description:
+ USB 2.0 devices that support hardware link power management (LPM)
+ L1 sleep state now use a best effort service latency value (BESL) to
+ indicate the best effort to resumption of service to the device after the
+ initiation of the resume event.
+ If the device does not have a preferred besl value then the host can select
+ one instead. This usb2_lpm_besl attribute allows to tune the host selected besl
+ value in order to tune power saving and service latency.
+
+ Supported values are 0 - 15.
+ More information on how besl values map to microseconds can be found in
+ USB 2.0 ECN Errata for Link Power Management, section 4.10)
+
+What: /sys/bus/usb/devices/.../rx_lanes
+Date: March 2018
+Contact: Mathias Nyman <mathias.nyman@linux.intel.com>
+Description:
+ Number of rx lanes the device is using.
+ USB 3.2 adds Dual-lane support, 2 rx and 2 tx lanes over Type-C.
+ Inter-Chip SSIC devices support asymmetric lanes up to 4 lanes per
+ direction. Devices before USB 3.2 are single lane (rx_lanes = 1)
+
+What: /sys/bus/usb/devices/.../tx_lanes
+Date: March 2018
+Contact: Mathias Nyman <mathias.nyman@linux.intel.com>
+Description:
+ Number of tx lanes the device is using.
+ USB 3.2 adds Dual-lane support, 2 rx and 2 tx -lanes over Type-C.
+ Inter-Chip SSIC devices support asymmetric lanes up to 4 lanes per
+ direction. Devices before USB 3.2 are single lane (tx_lanes = 1)
+
+What: /sys/bus/usb/devices/usbX/bAlternateSetting
+Description:
+ The current interface alternate setting number, in decimal.
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bcdDevice
+Description:
+ The device's release number, in hexadecimal.
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bConfigurationValue
+Description:
+ While a USB device typically have just one configuration
+ setting, some devices support multiple configurations.
+
+ This value shows the current configuration, in decimal.
+
+ Changing its value will change the device's configuration
+ to another setting.
+
+ The number of configurations supported by a device is at:
+
+ /sys/bus/usb/devices/usbX/bNumConfigurations
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bDeviceClass
+Description:
+ Class code of the device, in hexadecimal.
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bDeviceProtocol
+Description:
+ Protocol code of the device, in hexadecimal.
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bDeviceSubClass
+Description:
+ Subclass code of the device, in hexadecimal.
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bInterfaceClass
+Description:
+ Class code of the interface, in hexadecimal.
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bInterfaceNumber
+Description:
+ Interface number, in hexadecimal.
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bInterfaceProtocol
+Description:
+ Protocol code of the interface, in hexadecimal.
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bInterfaceSubClass
+Description:
+ Subclass code of the interface, in hexadecimal.
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bmAttributes
+Description:
+ Attributes of the current configuration, in hexadecimal.
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bMaxPacketSize0
+Description:
+ Maximum endpoint 0 packet size, in decimal.
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bMaxPower
+Description:
+ Maximum power consumption of the active configuration of
+ the device, in miliamperes.
+
+What: /sys/bus/usb/devices/usbX/bNumConfigurations
+Description:
+ Number of the possible configurations of the device, in
+ decimal. The current configuration is controlled via:
+
+ /sys/bus/usb/devices/usbX/bConfigurationValue
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bNumEndpoints
+Description:
+ Number of endpoints used on this interface, in hexadecimal.
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/bNumInterfaces
+Description:
+ Number of interfaces on this device, in decimal.
+
+What: /sys/bus/usb/devices/usbX/busnum
+Description:
+ Number of the bus.
+
+What: /sys/bus/usb/devices/usbX/configuration
+Description:
+ Contents of the string descriptor associated with the
+ current configuration. It may include the firmware version
+ of a device and/or its serial number.
+
+What: /sys/bus/usb/devices/usbX/descriptors
+Description:
+ Contains the interface descriptors, in binary.
+
+What: /sys/bus/usb/devices/usbX/idProduct
+Description:
+ Product ID, in hexadecimal.
+
+What: /sys/bus/usb/devices/usbX/idVendor
+Description:
+ Vendor ID, in hexadecimal.
+
+What: /sys/bus/usb/devices/usbX/devspec
+Description:
+ Displays the Device Tree Open Firmware node of the interface.
+
+What: /sys/bus/usb/devices/usbX/avoid_reset_quirk
+Description:
+ Most devices have this set to zero.
+
+ If the value is 1, enable a USB quirk that prevents this
+ device to use reset.
+
+ (read/write)
+
+What: /sys/bus/usb/devices/usbX/devnum
+Description:
+ USB interface device number, in decimal.
+
+What: /sys/bus/usb/devices/usbX/devpath
+Description:
+ String containing the USB interface device path.
+
+What: /sys/bus/usb/devices/usbX/manufacturer
+Description:
+ Vendor specific string containing the name of the
+ manufacturer of the device.
+
+What: /sys/bus/usb/devices/usbX/maxchild
+Description:
+ Number of ports of an USB hub
+
+What: /sys/bus/usb/devices/usbX/persist
+Description:
+ Keeps the device even if it gets disconnected.
+
+What: /sys/bus/usb/devices/usbX/product
+Description:
+ Vendor specific string containing the name of the
+ device's product.
+
+What: /sys/bus/usb/devices/usbX/speed
+Description:
+ Shows the device's max speed, according to the USB version,
+ in Mbps.
+ Can be:
+
+ ======= ====================
+ Unknown speed unknown
+ 1.5 Low speed
+ 15 Full speed
+ 480 High Speed
+ 5000 Super Speed
+ 10000 Super Speed+
+ 20000 Super Speed+ Gen 2x2
+ ======= ====================
+
+What: /sys/bus/usb/devices/usbX/supports_autosuspend
+Description:
+ Returns 1 if the device doesn't support autosuspend.
+ Otherwise, returns 0.
+
+What: /sys/bus/usb/devices/usbX/urbnum
+Description:
+ Number of URBs submitted for the whole device.
+
+What: /sys/bus/usb/devices/usbX/version
+Description:
+ String containing the USB device version, as encoded
+ at the BCD descriptor.
+
+What: /sys/bus/usb/devices/usbX/power/autosuspend
+Description:
+ Time in milliseconds for the device to autosuspend. If the
+ value is negative, then autosuspend is prevented.
+
+ (read/write)
+
+What: /sys/bus/usb/devices/usbX/power/active_duration
+Description:
+ The total time the device has not been suspended.
+
+What: /sys/bus/usb/devices/usbX/power/connected_duration
+Description:
+ The total time (in msec) that the device has been connected.
+
+What: /sys/bus/usb/devices/usbX/power/level
+Description:
+
+What: /sys/bus/usb/devices/usbX/ep_<N>/bEndpointAddress
+Description:
+ The address of the endpoint described by this descriptor,
+ in hexadecimal. The endpoint direction on this bitmapped field
+ is also shown at:
+
+ /sys/bus/usb/devices/usbX/ep_<N>/direction
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/ep_<N>/bInterval
+Description:
+ The interval of the endpoint as described on its descriptor,
+ in hexadecimal. The actual interval depends on the version
+ of the USB. Also shown in time units at
+ /sys/bus/usb/devices/usbX/ep_<N>/interval.
+
+What: /sys/bus/usb/devices/usbX/ep_<N>/bLength
+Description:
+ Number of bytes of the endpoint descriptor, in hexadecimal.
+
+What: /sys/bus/usb/devices/usbX/ep_<N>/bmAttributes
+Description:
+ Attributes which apply to the endpoint as described on its
+ descriptor, in hexadecimal. The endpoint type on this
+ bitmapped field is also shown at:
+
+ /sys/bus/usb/devices/usbX/ep_<N>/type
+
+ See USB specs for its meaning.
+
+What: /sys/bus/usb/devices/usbX/ep_<N>/direction
+Description:
+ Direction of the endpoint. Can be:
+
+ - both (on control endpoints)
+ - in
+ - out
+
+What: /sys/bus/usb/devices/usbX/ep_<N>/interval
+Description:
+ Interval for polling endpoint for data transfers, in
+ milisseconds or microseconds.
+
+What: /sys/bus/usb/devices/usbX/ep_<N>/type
+Description:
+ Descriptor type. Can be:
+
+ - Control
+ - Isoc
+ - Bulk
+ - Interrupt
+ - unknown
+
+What: /sys/bus/usb/devices/usbX/ep_<N>/wMaxPacketSize
+Description:
+ Maximum packet size this endpoint is capable of
+ sending or receiving, in hexadecimal.