4.9-stable review patch. If anyone has any objections, please let me know.
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From: Mathias Nyman mathias.nyman@linux.intel.com
commit 1208d8a84fdcae6b395c57911cdf907450d30e70 upstream.
When disabling a USB3 port the hub driver will set the port link state to U3 to prevent "ejected" or "safely removed" devices that are still physically connected from immediately re-enumerating.
If the device was really unplugged, then error messages were printed as the hub tries to set the U3 link state for a port that is no longer enabled.
xhci-hcd ee000000.usb: Cannot set link state. usb usb8-port1: cannot disable (err = -32)
Don't print error message in xhci-hub if hub tries to set port link state for a disabled port. Return -ENODEV instead which also silences hub driver.
Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Tested-by: Yoshihiro Shimoda yoshihiro.shimoda.uh@renesas.com Signed-off-by: Ross Zwisler zwisler@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/usb/host/xhci-hub.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-)
--- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -1072,17 +1072,17 @@ int xhci_hub_control(struct usb_hcd *hcd temp = readl(port_array[wIndex]); break; } - - /* Software should not attempt to set - * port link state above '3' (U3) and the port - * must be enabled. - */ - if ((temp & PORT_PE) == 0 || - (link_state > USB_SS_PORT_LS_U3)) { - xhci_warn(xhci, "Cannot set link state.\n"); + /* Port must be enabled */ + if (!(temp & PORT_PE)) { + retval = -ENODEV; + break; + } + /* Can't set port link state above '3' (U3) */ + if (link_state > USB_SS_PORT_LS_U3) { + xhci_warn(xhci, "Cannot set port %d link state %d\n", + wIndex, link_state); goto error; } - if (link_state == USB_SS_PORT_LS_U3) { slot_id = xhci_find_slot_id_by_port(hcd, xhci, wIndex + 1);