usb: xhci: check usb2 port capabilities before adding hw link PM support
Hardware link powermanagement in usb2 is a per-port capability.
Previously support for hw lpm was enabled for all ports if any usb2 port supported it.
Now instead cache the capability values and check them for each port individually
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 4a05555b..df5e881 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -4033,15 +4033,40 @@
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)