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-rw-r--r--Documentation/ABI/testing/sysfs-bus-usb32
1 files changed, 19 insertions, 13 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb
index 614d216dff1d..bf2c1968525f 100644
--- a/Documentation/ABI/testing/sysfs-bus-usb
+++ b/Documentation/ABI/testing/sysfs-bus-usb
@@ -9,6 +9,7 @@ Description:
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
@@ -72,24 +73,27 @@ Description:
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
+ 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
+ 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
+ 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
+ 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.
@@ -209,9 +213,11 @@ Description:
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
@@ -233,10 +239,10 @@ Description:
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:
+ udev event with the following attributes::
- OVER_CURRENT_PORT=/sys/bus/usb/devices/.../(hub interface)/portX
- OVER_CURRENT_COUNT=[current value of this sysfs attribute]
+ OVER_CURRENT_PORT=/sys/bus/usb/devices/.../(hub interface)/portX
+ OVER_CURRENT_COUNT=[current value of this sysfs attribute]
What: /sys/bus/usb/devices/.../(hub interface)/portX/usb3_lpm_permit
Date: November 2015