static int xhci_pci_resume(struct usb_hcd *hcd, bool hibernated)
{
struct xhci_hcd *xhci = hcd_to_xhci(hcd);
struct pci_dev *pdev = to_pci_dev(hcd->self.controller);
int retval = 0;
/* The BIOS on systems with the Intel Panther Point chipset may or may
* not support xHCI natively. That means that during system resume, it
* may switch the ports back to EHCI so that users can use their
* keyboard to select a kernel from GRUB after resume from hibernate.
*
* The BIOS is supposed to remember whether the OS had xHCI ports
* enabled before resume, and switch the ports back to xHCI when the
* BIOS/OS semaphore is written, but we all know we can't trust BIOS
* writers.
*
* Unconditionally switch the ports back to xHCI after a system resume.
* We can't tell whether the EHCI or xHCI controller will be resumed
* first, so we have to do the port switchover in both drivers. Writing
* a '1' to the port switchover registers should have no effect if the
* port was already switched over.
*/
if (usb_is_intel_switchable_xhci(pdev))
usb_enable_xhci_ports(pdev);
retval = xhci_resume(xhci, hibernated);
return retval;
}
static void ehci_enable_xhci_companion(void)
{
struct pci_dev *companion = NULL;
/* The xHCI and EHCI controllers are not on the same PCI slot */
for_each_pci_dev(companion) {
if (!usb_is_intel_switchable_xhci(companion))
continue;
usb_enable_xhci_ports(companion);
return;
}
}
static void ehci_enable_xhci_companion(void)
{
struct pci_dev *companion = NULL;
for_each_pci_dev(companion) {
if (!usb_is_intel_switchable_xhci(companion))
continue;
usb_enable_xhci_ports(companion);
return;
}
}