usb: ehci: tegra: Correctly handle GetPortStatus during Resume

Multiple GetPortStatus requests can be made while the
USB bus is resuming.  All requests must be handled
properly to prevent incorrect disconnect detection
during Resume and improper indentification of
Resume signaling as a remote wakeup event.

Change-Id: Ib07f83a2bab5699b2d95533d26d0a6bf541c697d
Signed-off-by: Nathan Connell <w14185@motorola.com>

diff --git a/drivers/usb/host/ehci-tegra.c b/drivers/usb/host/ehci-tegra.c
index d487cdaab3529b86541bcf2744c3dcd1d7be8fcd..9738b994f391a4fa3dfd1c37932ac2710724d143 100644 (file)
--- a/drivers/usb/host/ehci-tegra.c
+++ b/drivers/usb/host/ehci-tegra.c
@@ -94,9 +94,12 @@ static int tegra_ehci_hub_control(
 
        else if (typeReq == GetPortStatus) {
                temp = ehci_readl(ehci, status_reg);
-               if (tegra->port_resuming && !(temp & PORT_SUSPEND)) {
+               if (tegra->port_resuming && !(temp & PORT_SUSPEND) &&
+                   time_after_eq(jiffies, ehci->reset_done[wIndex-1])) {
                        /* Resume completed, re-enable disconnect detection */
                        tegra->port_resuming = 0;
+                       clear_bit((wIndex & 0xff) - 1, &ehci->suspended_ports);
+                       ehci->reset_done[wIndex-1] = 0;
                        tegra_usb_phy_postresume(tegra->phy);
                }
        }
@@ -142,11 +145,11 @@ static int tegra_ehci_hub_control(
                if (!(temp & PORT_SUSPEND))
                        goto done;
 
+               tegra->port_resuming = 1;
+
                /* Disable disconnect detection during port resume */
                tegra_usb_phy_preresume(tegra->phy);
 
-               ehci->reset_done[wIndex-1] = jiffies + msecs_to_jiffies(25);
-
                ehci_dbg(ehci, "%s:USBSTS = 0x%x", __func__,
                        ehci_readl(ehci, &ehci->regs->status));
                usbsts_reg = ehci_readl(ehci, &ehci->regs->status);
@@ -168,22 +171,11 @@ static int tegra_ehci_hub_control(
 
                udelay(20);
                temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
-               /* start resume signalling */
+               /* start resume signaling */
                ehci_writel(ehci, temp | PORT_RESUME, status_reg);
 
-               spin_unlock_irqrestore(&ehci->lock, flags);
-               msleep(20);
-               spin_lock_irqsave(&ehci->lock, flags);
-
-               /* Poll until the controller clears RESUME and SUSPEND */
-               if (handshake(ehci, status_reg, PORT_RESUME, 0, 2000))
-                       pr_err("%s: timeout waiting for RESUME\n", __func__);
-               if (handshake(ehci, status_reg, PORT_SUSPEND, 0, 2000))
-                       pr_err("%s: timeout waiting for SUSPEND\n", __func__);
-
-               ehci->reset_done[wIndex-1] = 0;
-
-               tegra->port_resuming = 1;
+               ehci->reset_done[wIndex-1] = jiffies + msecs_to_jiffies(25);
+               /* whoever resumes must GetPortStatus to complete it!! */
                goto done;
        }
 
@@ -402,8 +394,6 @@ static int tegra_ehci_bus_resume(struct usb_hcd *hcd)
                tegra->bus_suspended = 0;
        }
 
-       tegra_usb_phy_preresume(tegra->phy);
-       tegra->port_resuming = 1;
        return ehci_bus_resume(hcd);
 }
 #endif