diff options
Diffstat (limited to 'drivers/usb/core')
| -rw-r--r-- | drivers/usb/core/hub.c | 28 |
1 files changed, 16 insertions, 12 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 026b652d4f38..572e8c26a129 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3999,6 +3999,9 @@ static int usb_set_lpm_timeout(struct usb_device *udev, * control transfers to set the hub timeout or enable device-initiated U1/U2 * will be successful. * + * If the control transfer to enable device-initiated U1/U2 entry fails, then + * hub-initiated U1/U2 will be disabled. + * * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI * driver know about it. If that call fails, it should be harmless, and just * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency. @@ -4053,23 +4056,24 @@ static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev, * host know that this link state won't be enabled. */ hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state); - } else { - /* Only a configured device will accept the Set Feature - * U1/U2_ENABLE - */ - if (udev->actconfig) - usb_set_device_initiated_lpm(udev, state, true); + return; + } - /* As soon as usb_set_lpm_timeout(timeout) returns 0, the - * hub-initiated LPM is enabled. Thus, LPM is enabled no - * matter the result of usb_set_device_initiated_lpm(). - * The only difference is whether device is able to initiate - * LPM. - */ + /* Only a configured device will accept the Set Feature + * U1/U2_ENABLE + */ + if (udev->actconfig && + usb_set_device_initiated_lpm(udev, state, true) == 0) { if (state == USB3_LPM_U1) udev->usb3_lpm_u1_enabled = 1; else if (state == USB3_LPM_U2) udev->usb3_lpm_u2_enabled = 1; + } else { + /* Don't request U1/U2 entry if the device + * cannot transition to U1/U2. + */ + usb_set_lpm_timeout(udev, state, 0); + hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state); } } |