USB: EHCI: add delay during suspend to prevent erroneous wakeups

[karo-tx-linux.git] / drivers / usb / host / ehci-hub.c

diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 47b858fc50b2ee484c035cef8fe8b27c669009b5..7ae0c4d517417d46dbc2dd8f51993728fa839c3a 100644 (file)
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -238,6 +238,7 @@ static int ehci_bus_suspend (struct usb_hcd *hcd)
        int                     port;
        int                     mask;
        int                     changed;
+       bool                    fs_idle_delay;
 
        ehci_dbg(ehci, "suspend root hub\n");
 
@@ -272,6 +273,7 @@ static int ehci_bus_suspend (struct usb_hcd *hcd)
        ehci->bus_suspended = 0;
        ehci->owned_ports = 0;
        changed = 0;
+       fs_idle_delay = false;
        port = HCS_N_PORTS(ehci->hcs_params);
        while (port--) {
                u32 __iomem     *reg = &ehci->regs->port_status [port];
@@ -300,16 +302,32 @@ static int ehci_bus_suspend (struct usb_hcd *hcd)
                }
 
                if (t1 != t2) {
+                       /*
+                        * On some controllers, Wake-On-Disconnect will
+                        * generate false wakeup signals until the bus
+                        * switches over to full-speed idle.  For their
+                        * sake, add a delay if we need one.
+                        */
+                       if ((t2 & PORT_WKDISC_E) &&
+                                       ehci_port_speed(ehci, t2) ==
+                                               USB_PORT_STAT_HIGH_SPEED)
+                               fs_idle_delay = true;
                        ehci_writel(ehci, t2, reg);
                        changed = 1;
                }
        }
+       spin_unlock_irq(&ehci->lock);
+
+       if ((changed && ehci->has_tdi_phy_lpm) || fs_idle_delay) {
+               /*
+                * Wait for HCD to enter low-power mode or for the bus
+                * to switch to full-speed idle.
+                */
+               usleep_range(5000, 5500);
+       }
 
        if (changed && ehci->has_tdi_phy_lpm) {
-               spin_unlock_irq(&ehci->lock);
-               msleep(5);      /* 5 ms for HCD to enter low-power mode */
                spin_lock_irq(&ehci->lock);
-
                port = HCS_N_PORTS(ehci->hcs_params);
                while (port--) {
                        u32 __iomem     *hostpc_reg = &ehci->regs->hostpc[port];
@@ -322,8 +340,8 @@ static int ehci_bus_suspend (struct usb_hcd *hcd)
                                        port, (t3 & HOSTPC_PHCD) ?
                                        "succeeded" : "failed");
                }
+               spin_unlock_irq(&ehci->lock);
        }
-       spin_unlock_irq(&ehci->lock);
 
        /* Apparently some devices need a >= 1-uframe delay here */
        if (ehci->bus_suspended)