From: Alan Stern Date: Tue, 14 Aug 2007 14:56:10 +0000 (-0400) Subject: USB: accept 1-byte Device Status replies, fixing some b0rken devices X-Git-Tag: firefly_0821_release~26670^2~17 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=46dede4690bbb23a2c9d60561e2e4fdc3e6bee61;p=firefly-linux-kernel-4.4.55.git 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 disconnected. 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: Alan Stern Acked-by: David Brownell Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index e341a1da517f..f7b337feb3ea 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -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) {