diff options
Diffstat (limited to 'drivers/usb/host/xhci.c')
| -rw-r--r-- | drivers/usb/host/xhci.c | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 4a05555bf6e3..df5e881e3bc5 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -4033,15 +4033,40 @@ int xhci_set_usb2_hardware_lpm(struct usb_hcd *hcd, return 0; } +/* check if a usb2 port supports a given extened capability protocol + * only USB2 ports extended protocol capability values are cached. + * Return 1 if capability is supported + */ +static int xhci_check_usb2_port_capability(struct xhci_hcd *xhci, int port, + unsigned capability) +{ + u32 port_offset, port_count; + int i; + + for (i = 0; i < xhci->num_ext_caps; i++) { + if (xhci->ext_caps[i] & capability) { + /* port offsets starts at 1 */ + port_offset = XHCI_EXT_PORT_OFF(xhci->ext_caps[i]) - 1; + port_count = XHCI_EXT_PORT_COUNT(xhci->ext_caps[i]); + if (port >= port_offset && + port < port_offset + port_count) + return 1; + } + } + return 0; +} + int xhci_update_device(struct usb_hcd *hcd, struct usb_device *udev) { struct xhci_hcd *xhci = hcd_to_xhci(hcd); int ret; + int portnum = udev->portnum - 1; ret = xhci_usb2_software_lpm_test(hcd, udev); if (!ret) { xhci_dbg(xhci, "software LPM test succeed\n"); - if (xhci->hw_lpm_support == 1) { + if (xhci->hw_lpm_support == 1 && + xhci_check_usb2_port_capability(xhci, portnum, XHCI_HLC)) { udev->usb2_hw_lpm_capable = 1; ret = xhci_set_usb2_hardware_lpm(hcd, udev, 1); if (!ret) |