An empty port can transition to either Inactive or Compliance Mode if a newly connected USB 3.0 device fails to link train. In that case, we issue a warm reset. Some devices, such as John's Roseweil eusb3 enclosure, slip back into Compliance Mode after the warm reset. The current warm reset code does not check for device connect status on warm reset completion, and it incorrectly reports the warm reset succeeded. This causes the USB core to attempt to send a Set Address control transfer to a port in Compliance Mode, which will always fail. Make hub_port_wait_reset check the current connect status and link state after the warm reset completes. Return a failure status if the device is disconnected or the link state is Compliance Mode or SS.Inactive. Make hub_events disable the port if warm reset fails. This will disable the port, and then bring it back into the RxDetect state. Make the USB core ignore the connect change until the device reconnects. Note that this patch does NOT handle connected devices slipping into the Inactive state very well. This is a concern, because devices can go into the Inactive state on U1/U2 exit failure. However, the fix for that case is too large for stable, so it will be submitted in a separate patch. This patch should be backported to kernels as old as 3.2, contain the commit ID 75d7cf72ab9fa01dc70877aa5c68e8ef477229dc "usbcore: refine warm reset logic" Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Reported-by: John Covici <covici@xxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx --- drivers/usb/core/hub.c | 12 +++++++++++- 1 files changed, 11 insertions(+), 1 deletions(-) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 42566d7..9641e9c 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2597,6 +2597,11 @@ static int hub_port_wait_reset(struct usb_hub *hub, int port1, return 0; } } else { + if (!(portstatus & USB_PORT_STAT_CONNECTION) || + hub_port_warm_reset_required(hub, + portstatus)) + return -ENOTCONN; + return 0; } @@ -4694,9 +4699,14 @@ static void hub_events(void) * SS.Inactive state. */ if (hub_port_warm_reset_required(hub, portstatus)) { + int status; + dev_dbg(hub_dev, "warm reset port %d\n", i); - hub_port_reset(hub, i, NULL, + status = hub_port_reset(hub, i, NULL, HUB_BH_RESET_TIME, true); + if (status < 0) + hub_port_disable(hub, i, 1); + connect_change = 0; } if (connect_change) -- 1.7.9 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html