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Diffstat (limited to 'Documentation/ABI/testing/sysfs-bus-usb')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-usb | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb index c6e9b30f05b13..a31a66d62cbba 100644 --- a/Documentation/ABI/testing/sysfs-bus-usb +++ b/Documentation/ABI/testing/sysfs-bus-usb @@ -189,6 +189,24 @@ Description: The file will read "hotplug", "wired" and "not used" if the information is available, and "unknown" otherwise. +What: /sys/bus/usb/devices/.../(hub interface)/portX/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. + What: /sys/bus/usb/devices/.../(hub interface)/portX/over_current_count Date: February 2018 Contact: Richard Leitner <richard.leitner@skidata.com> |