Documentation/ABI/testing/sysfs-bus-usb
Source file repositories/reference/linux-study-clean/Documentation/ABI/testing/sysfs-bus-usb
File Facts
- System
- Linux kernel
- Corpus path
Documentation/ABI/testing/sysfs-bus-usb- Extension
[no extension]- Size
- 21365 bytes
- Lines
- 608
- Domain
- Support Tooling And Documentation
- Bucket
- Documentation
- Inferred role
- Support Tooling And Documentation: Documentation
- Status
- atlas-only
Why This File Exists
Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
Dependency Surface
- No C-style include directives detected by the generator.
Detected Declarations
- No top-level syscall, struct, function, initcall, or export declaration detected by the generator.
Annotated Snippet
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:
Annotation
- Atlas domain: Support Tooling And Documentation / Documentation.
- Implementation status: atlas-only.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.