USB: xHCI: PCI power management implementation

This patch implements the PCI suspend/resume.

Please refer to xHCI spec for doing the suspend/resume operation.

For S3, CSS/SRS in USBCMD is used to save/restore the internal state.
However, an error maybe occurs while restoring the internal state.
In this case, it means that HC internal state is wrong and HC will be
re-initialized.

Signed-off-by: Libin Yang <libin.yang@amd.com>
Signed-off-by: Dong Nguyen <dong.nguyen@amd.com>
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 15 insertions, 1 deletions

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 196e21fb36ff..c08928adc524 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -191,7 +191,7 @@ struct xhci_op_regs {
 /* bits 4:6 are reserved (and should be preserved on writes). */
 /* light reset (port status stays unchanged) - reset completed when this is 0 */
 #define CMD_LRESET      (1 << 7)
-/* FIXME: ignoring host controller save/restore state for now. */
+/* host controller save/restore state. */
 #define CMD_CSS         (1 << 8)
 #define CMD_CRS         (1 << 9)
 /* Enable Wrap Event - '1' means xHC generates an event when MFINDEX wraps. */
@@ -1130,6 +1130,17 @@ struct urb_priv {
 #define XHCI_STOP_EP_CMD_TIMEOUT        5
 /* XXX: Make these module parameters */
 
+struct s3_save {
+        u32     command;
+        u32     dev_nt;
+        u64     dcbaa_ptr;
+        u32     config_reg;
+        u32     irq_pending;
+        u32     irq_control;
+        u32     erst_size;
+        u64     erst_base;
+        u64     erst_dequeue;
+};
 
 /* There is one ehci_hci structure per controller */
 struct xhci_hcd {
@@ -1198,6 +1209,7 @@ struct xhci_hcd {
         unsigned long           next_statechange;
 
         u32                     command;
+        struct s3_save          s3;
 /* Host controller is dying - not responding to commands. "I'm not dead yet!"
  *
  * xHC interrupts have been disabled and a watchdog timer will (or has already)
@@ -1393,6 +1405,8 @@ int xhci_init(struct usb_hcd *hcd);
 int xhci_run(struct usb_hcd *hcd);
 void xhci_stop(struct usb_hcd *hcd);
 void xhci_shutdown(struct usb_hcd *hcd);
+int xhci_suspend(struct xhci_hcd *xhci);
+int xhci_resume(struct xhci_hcd *xhci, bool hibernated);
 int xhci_get_frame(struct usb_hcd *hcd);
 irqreturn_t xhci_irq(struct usb_hcd *hcd);
 irqreturn_t xhci_msi_irq(int irq, struct usb_hcd *hcd);