[PATCH] USB UHCI: Add root-hub suspend/resume support

This patch implements (finally!) separate suspend and resume routines
for the root hub and the controller in the UHCI driver.  It also
changes the sequence used to reset the controller during initial
probing, so as to preserve the existing state during a Resume-From-Disk.
(This new sequence is what should be used in the PCI Quirks code for
early USB handoffs, incidentally.)  Lastly it adds a notion of the
controller being "inaccessible" while in a PCI low-power state, when
normal I/O operations shouldn't be allowed.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 8 insertions, 2 deletions

diff --git a/drivers/usb/host/uhci-hcd.h b/drivers/usb/host/uhci-hcd.h
index 4bac57c74ec2..827df5e06800 100644
--- a/drivers/usb/host/uhci-hcd.h
+++ b/drivers/usb/host/uhci-hcd.h
@@ -41,6 +41,7 @@
 #define USBFRNUM        6
 #define USBFLBASEADD    8
 #define USBSOF          12
+#define   USBSOF_DEFAULT        64      /* Frame length is exactly 1 ms */
 
 /* USB port status and control registers */
 #define USBPORTSC1      16
@@ -66,6 +67,8 @@
 /* Legacy support register */
 #define USBLEGSUP               0xc0
 #define   USBLEGSUP_DEFAULT     0x2000  /* only PIRQ enable set */
+#define   USBLEGSUP_RWC         0x8f00  /* the R/WC bits */
+#define   USBLEGSUP_RO          0x5040  /* R/O and reserved bits */
 
 #define UHCI_NULL_DATA_SIZE     0x7FF   /* for UHCI controller TD */
 
@@ -325,8 +328,9 @@ static inline int __interval_to_skel(int interval)
  */
 enum uhci_rh_state {
         /* In the next 4 states the HC must be halted */
-        UHCI_RH_RESET,
+        UHCI_RH_RESET,                  /* These two must come first */
         UHCI_RH_SUSPENDED,
+
         UHCI_RH_AUTO_STOPPED,
         UHCI_RH_RESUMING,
 
@@ -334,7 +338,8 @@ enum uhci_rh_state {
          * can legally appear either way */
         UHCI_RH_SUSPENDING,
 
-        /* In the next two states it's an error if the HC is halted */
+        /* In the next two states it's an error if the HC is halted.
+         * These two must come last */
         UHCI_RH_RUNNING,                /* The normal state */
         UHCI_RH_RUNNING_NODEVS,         /* Running with no devices attached */
 };
@@ -376,6 +381,7 @@ struct uhci_hcd {
         unsigned int scan_in_progress:1;        /* Schedule scan is running */
         unsigned int need_rescan:1;             /* Redo the schedule scan */
         unsigned int resume_detect:1;           /* Need a Global Resume */
+        unsigned int hc_inaccessible:1;         /* HC is suspended or dead */
 
         /* Support for port suspend/resume/reset */
         unsigned long port_c_suspend;           /* Bit-arrays of ports */