xhci: Change hcd_priv into a pointer.

Instead of allocating space for the whole xhci_hcd structure at the end of
usb_hcd, make the USB core allocate enough space for a pointer to the
xhci_hcd structure.  This will make it easy to share the xhci_hcd
structure across the two roothubs (the USB 3.0 usb_hcd and the USB 2.0
usb_hcd).

Deallocate the xhci_hcd at PCI remove time, so the hcd_priv will be
deallocated after the usb_hcd is deallocated.  We do this by registering a
different PCI remove function that calls the usb_hcd_pci_remove()
function, and then frees the xhci_hcd.  usb_hcd_pci_remove() calls
kput() on the usb_hcd structure, which will deallocate the memory that
contains the hcd_priv pointer, but not the memory it points to.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index c4e70c6d809..daa88581ad6 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1163,6 +1163,7 @@ struct s3_save {
 
 /* There is one ehci_hci structure per controller */
 struct xhci_hcd {
+        struct usb_hcd *main_hcd;
         /* glue to PCI and HCD framework */
         struct xhci_cap_regs __iomem *cap_regs;
         struct xhci_op_regs __iomem *op_regs;
@@ -1266,12 +1267,12 @@ struct xhci_hcd {
 /* convert between an HCD pointer and the corresponding EHCI_HCD */
 static inline struct xhci_hcd *hcd_to_xhci(struct usb_hcd *hcd)
 {
-        return (struct xhci_hcd *) (hcd->hcd_priv);
+        return *((struct xhci_hcd **) (hcd->hcd_priv));
 }
 
 static inline struct usb_hcd *xhci_to_hcd(struct xhci_hcd *xhci)
 {
-        return container_of((void *) xhci, struct usb_hcd, hcd_priv);
+        return xhci->main_hcd;
 }
 
 #ifdef CONFIG_USB_XHCI_HCD_DEBUGGING