EHCI: fix interrupt-driven remote wakeup

Now that port status change notifications are interrupt-driven,
ehci-hcd needs to tell usbcore when a remote-wakeup resume operation
is finished -- we can no longer rely on the core to poll and find
out.  This patch (as843) uses the root-hub status timer to force a
poll after the resume is complete.

The patch also changes the test for detecting when the TDRSMDN resume
period has expired.  It's necessary to use time_after_eq() instead of
time_after(), since the polling is triggered precisely by a timer.
The same change is made for TDRSTR reset expiration, for consistency.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 32 insertions, 18 deletions

diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 3cfba69e0767..0d83c6df1a3b 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -379,8 +379,8 @@ ehci_hub_status_data (struct usb_hcd *hcd, char *buf)
                         ehci->reset_done [i] = 0;
                 if ((temp & mask) != 0
                                 || ((temp & PORT_RESUME) != 0
-                                        && time_after (jiffies,
-                                                ehci->reset_done [i]))) {
+                                        && time_after_eq(jiffies,
+                                                ehci->reset_done[i]))) {
                         if (i < 7)
                             buf [0] |= 1 << (i + 1);
                         else
@@ -554,31 +554,45 @@ static int ehci_hub_control (
                         status |= 1 << USB_PORT_FEAT_C_OVER_CURRENT;
 
                 /* whoever resumes must GetPortStatus to complete it!! */
-                if ((temp & PORT_RESUME)
-                                && time_after (jiffies,
-                                        ehci->reset_done [wIndex])) {
-                        status |= 1 << USB_PORT_FEAT_C_SUSPEND;
-                        ehci->reset_done [wIndex] = 0;
+                if (temp & PORT_RESUME) {
 
-                        /* stop resume signaling */
-                        temp = ehci_readl(ehci, status_reg);
-                        ehci_writel(ehci,
+                        /* Remote Wakeup received? */
+                        if (!ehci->reset_done[wIndex]) {
+                                /* resume signaling for 20 msec */
+                                ehci->reset_done[wIndex] = jiffies
+                                                + msecs_to_jiffies(20);
+                                /* check the port again */
+                                mod_timer(&ehci_to_hcd(ehci)->rh_timer,
+                                                ehci->reset_done[wIndex]);
+                        }
+
+                        /* resume completed? */
+                        else if (time_after_eq(jiffies,
+                                        ehci->reset_done[wIndex])) {
+                                status |= 1 << USB_PORT_FEAT_C_SUSPEND;
+                                ehci->reset_done[wIndex] = 0;
+
+                                /* stop resume signaling */
+                                temp = ehci_readl(ehci, status_reg);
+                                ehci_writel(ehci,
                                         temp & ~(PORT_RWC_BITS | PORT_RESUME),
                                         status_reg);
-                        retval = handshake(ehci, status_reg,
+                                retval = handshake(ehci, status_reg,
                                            PORT_RESUME, 0, 2000 /* 2msec */);
-                        if (retval != 0) {
-                                ehci_err (ehci, "port %d resume error %d\n",
-                                        wIndex + 1, retval);
-                                goto error;
+                                if (retval != 0) {
+                                        ehci_err(ehci,
+                                                "port %d resume error %d\n",
+                                                wIndex + 1, retval);
+                                        goto error;
+                                }
+                                temp &= ~(PORT_SUSPEND|PORT_RESUME|(3<<10));
                         }
-                        temp &= ~(PORT_SUSPEND|PORT_RESUME|(3<<10));
                 }
 
                 /* whoever resets must GetPortStatus to complete it!! */
                 if ((temp & PORT_RESET)
-                                && time_after (jiffies,
-                                        ehci->reset_done [wIndex])) {
+                                && time_after_eq(jiffies,
+                                        ehci->reset_done[wIndex])) {
                         status |= 1 << USB_PORT_FEAT_C_RESET;
                         ehci->reset_done [wIndex] = 0;