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| author | Alan Stern <stern@rowland.harvard.edu> | 2017-06-05 10:28:01 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-06-13 10:48:24 +0200 |
| commit | c01b244ad848ac7f0faa141182db80650a8a761a (patch) | |
| tree | 5e6fbad5316fc3915609e013fc1875ff36af0d64 /tools/perf/scripts/python/stackcollapse.py | |
| parent | 81606aea2303aa11867e97030299b1057091c2fd (diff) | |
USB: add usbfs ioctl to retrieve the connection speed
The usbfs interface does not provide any way for the user to learn the
speed at which a device is connected. The current API includes a
USBDEVFS_CONNECTINFO ioctl, but all it provides is the device's
address and a one-bit value indicating whether the connection is low
speed. That may have sufficed in the era of USB-1.1, but it isn't
good enough today.
This patch introduces a new ioctl, USBDEVFS_GET_SPEED, which returns a
numeric value indicating the speed of the connection: unknown, low,
full, high, wireless, super, or super-plus.
Similar information (not exactly the same) is available through sysfs,
but it seems reasonable to provide the actual value in usbfs.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Reinhard Huck <reinhard.huck@thesycon.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'tools/perf/scripts/python/stackcollapse.py')
0 files changed, 0 insertions, 0 deletions