Commit 46dede46 authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
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USB: accept 1-byte Device Status replies, fixing some b0rken devices

Some devices have a bug which causes them to send a 1-byte reply to
Get-Device-Status requests instead of 2 bytes as required by the
spec.  This doesn't play well with autosuspend, since we look for a
valid status reply to make sure the device is still present when it
resumes.  Without both bytes, we assume the device has been

Lack of the second byte shouldn't matter much, since the spec requires
it always to be equal to 0.  Hence this patch (as959) causes
finish_port_resume() to accept a 1-byte reply as valid.
Signed-off-by: default avatarAlan Stern <>
Acked-by: default avatarDavid Brownell <>
Signed-off-by: default avatarGreg Kroah-Hartman <>
parent f095137e
......@@ -1644,9 +1644,10 @@ static int finish_port_resume(struct usb_device *udev)
* and device drivers will know about any resume quirks.
if (status == 0) {
devstatus = 0;
status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
if (status >= 0)
status = (status == 2 ? 0 : -ENODEV);
status = (status > 0 ? 0 : -ENODEV);
if (status) {
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