USB: EHCI: improve use of per-port status-change bits

This patch (as1634) simplifies some of the code associated with the
per-port change bits added in EHCI-1.1, and in particular it fixes a
bug in the logic of ehci_hub_status_data().  Even if the change bit
doesn't indicate anything happened on a particular port, we still have
to notify the core about changes to the suspend or reset status.

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

1 files changed, 5 insertions, 4 deletions

diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 4d3b294f203e..576b735f49b6 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -590,7 +590,7 @@ ehci_hub_status_data (struct usb_hcd *hcd, char *buf)
         u32             mask;
         int             ports, i, retval = 1;
         unsigned long   flags;
-        u32             ppcd = 0;
+        u32             ppcd = ~0;
 
         /* init status to no-changes */
         buf [0] = 0;
@@ -628,9 +628,10 @@ ehci_hub_status_data (struct usb_hcd *hcd, char *buf)
 
         for (i = 0; i < ports; i++) {
                 /* leverage per-port change bits feature */
-                if (ehci->has_ppcd && !(ppcd & (1 << i)))
-                        continue;
-                temp = ehci_readl(ehci, &ehci->regs->port_status [i]);
+                if (ppcd & (1 << i))
+                        temp = ehci_readl(ehci, &ehci->regs->port_status[i]);
+                else
+                        temp = 0;
 
                 /*
                  * Return status information even for ports with OWNER set.