3.19.8-ckt18 -stable review patch. If anyone has any objections, please let me know.
---8<------------------------------------------------------------ From: Oliver Neukum <oneu...@suse.com> commit 264904ccc33c604d4b3141bbd33808152dfac45b upstream. Some devices I got show an inability to operate right after power on if they are already connected. They are beyond recovery if the descriptors are requested multiple times. So in case of a timeout we rather bail early and reset again. But it must be done only on the first loop lest we get into a reset/time out spiral that can be overcome with a retry. This patch is a rework of a patch that fell through the cracks. http://www.spinics.net/lists/linux-usb/msg103263.html Signed-off-by: Oliver Neukum <oneu...@suse.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> Signed-off-by: Kamal Mostafa <ka...@canonical.com> --- drivers/usb/core/hub.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 5630198..61d8b51 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -4389,7 +4389,13 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1, r = -EPROTO; break; } - if (r == 0) + /* + * Some devices time out if they are powered on + * when already connected. They need a second + * reset. But only on the first attempt, + * lest we get into a time out/reset loop + */ + if (r == 0 || (r == -ETIMEDOUT && j == 0)) break; } udev->descriptor.bMaxPacketSize0 = -- 2.7.4
