diff options
| -rw-r--r-- | drivers/usb/core/hub.c | 24 | ||||
| -rw-r--r-- | drivers/usb/host/xhci-hub.c | 8 | ||||
| -rw-r--r-- | drivers/usb/host/xhci-pci.c | 6 |
3 files changed, 21 insertions, 17 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index f6c6b6f7cc9c..763c3134dd78 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -141,19 +141,27 @@ static int usb_device_supports_lpm(struct usb_device *udev) return 0; } - /* All USB 3.0 must support LPM, but we need their max exit latency - * information from the SuperSpeed Extended Capabilities BOS descriptor. + /* + * According to the USB 3.0 spec, all USB 3.0 devices must support LPM. + * However, there are some that don't, and they set the U1/U2 exit + * latencies to zero. */ if (!udev->bos->ss_cap) { - dev_warn(&udev->dev, "No LPM exit latency info found. " - "Power management will be impacted.\n"); + dev_info(&udev->dev, "No LPM exit latency info found, disabling LPM.\n"); return 0; } - if (udev->parent->lpm_capable) - return 1; - dev_warn(&udev->dev, "Parent hub missing LPM exit latency info. " - "Power management will be impacted.\n"); + if (udev->bos->ss_cap->bU1devExitLat == 0 && + udev->bos->ss_cap->bU2DevExitLat == 0) { + if (udev->parent) + dev_info(&udev->dev, "LPM exit latency is zeroed, disabling LPM.\n"); + else + dev_info(&udev->dev, "We don't know the algorithms for LPM for this host, disabling LPM.\n"); + return 0; + } + + if (!udev->parent || udev->parent->lpm_capable) + return 1; return 0; } diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index 9992fbfec85f..1ad6bc1951c7 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -732,9 +732,11 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, /* Set the U1 and U2 exit latencies. */ memcpy(buf, &usb_bos_descriptor, USB_DT_BOS_SIZE + USB_DT_USB_SS_CAP_SIZE); - temp = readl(&xhci->cap_regs->hcs_params3); - buf[12] = HCS_U1_LATENCY(temp); - put_unaligned_le16(HCS_U2_LATENCY(temp), &buf[13]); + if ((xhci->quirks & XHCI_LPM_SUPPORT)) { + temp = readl(&xhci->cap_regs->hcs_params3); + buf[12] = HCS_U1_LATENCY(temp); + put_unaligned_le16(HCS_U2_LATENCY(temp), &buf[13]); + } /* Indicate whether the host has LTM support. */ temp = readl(&xhci->cap_regs->hcc_params); diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c index 04f986d9234f..6c03584ac15f 100644 --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -222,12 +222,6 @@ static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) goto put_usb3_hcd; /* Roothub already marked as USB 3.0 speed */ - /* We know the LPM timeout algorithms for this host, let the USB core - * enable and disable LPM for devices under the USB 3.0 roothub. - */ - if (xhci->quirks & XHCI_LPM_SUPPORT) - hcd_to_bus(xhci->shared_hcd)->root_hub->lpm_capable = 1; - return 0; put_usb3_hcd: |