EHCI: don't hide ports owned by the companion

This patch (as709) changes the way ehci-hcd presents port status
values for ports owned by the companion controller.  It no longer
hides the information; in particular, it allows the core to see the
disconnect event that occurs when a full- or low-speed device is
switched over to the companion.  This is required for the next patch
in this series.

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

1 files changed, 35 insertions, 29 deletions

diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 12f881ff4b23..076474d95dbf 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -270,16 +270,14 @@ ehci_hub_status_data (struct usb_hcd *hcd, char *buf)
         spin_lock_irqsave (&ehci->lock, flags);
         for (i = 0; i < ports; i++) {
                 temp = ehci_readl(ehci, &ehci->regs->port_status [i]);
-                if (temp & PORT_OWNER) {
-                        /* don't report this in GetPortStatus */
-                        if (temp & PORT_CSC) {
-                                temp &= ~PORT_RWC_BITS;
-                                temp |= PORT_CSC;
-                                ehci_writel(ehci, temp,
-                                            &ehci->regs->port_status [i]);
-                        }
-                        continue;
-                }
+
+                /*
+                 * Return status information even for ports with OWNER set.
+                 * Otherwise khubd wouldn't see the disconnect event when a
+                 * high-speed device is switched over to the companion
+                 * controller by the user.
+                 */
+
                 if (!(temp & PORT_CONNECT))
                         ehci->reset_done [i] = 0;
                 if ((temp & mask) != 0
@@ -377,8 +375,13 @@ static int ehci_hub_control (
                         goto error;
                 wIndex--;
                 temp = ehci_readl(ehci, status_reg);
-                if (temp & PORT_OWNER)
-                        break;
+
+                /*
+                 * Even if OWNER is set, so the port is owned by the
+                 * companion controller, khubd needs to be able to clear
+                 * the port-change status bits (especially
+                 * USB_PORT_FEAT_C_CONNECTION).
+                 */
 
                 switch (wValue) {
                 case USB_PORT_FEAT_ENABLE:
@@ -501,24 +504,27 @@ static int ehci_hub_control (
                                         ehci_readl(ehci, status_reg));
                 }
 
-                // don't show wPortStatus if it's owned by a companion hc
-                if (!(temp & PORT_OWNER)) {
-                        if (temp & PORT_CONNECT) {
-                                status |= 1 << USB_PORT_FEAT_CONNECTION;
-                                // status may be from integrated TT
-                                status |= ehci_port_speed(ehci, temp);
-                        }
-                        if (temp & PORT_PE)
-                                status |= 1 << USB_PORT_FEAT_ENABLE;
-                        if (temp & (PORT_SUSPEND|PORT_RESUME))
-                                status |= 1 << USB_PORT_FEAT_SUSPEND;
-                        if (temp & PORT_OC)
-                                status |= 1 << USB_PORT_FEAT_OVER_CURRENT;
-                        if (temp & PORT_RESET)
-                                status |= 1 << USB_PORT_FEAT_RESET;
-                        if (temp & PORT_POWER)
-                                status |= 1 << USB_PORT_FEAT_POWER;
+                /*
+                 * Even if OWNER is set, there's no harm letting khubd
+                 * see the wPortStatus values (they should all be 0 except
+                 * for PORT_POWER anyway).
+                 */
+
+                if (temp & PORT_CONNECT) {
+                        status |= 1 << USB_PORT_FEAT_CONNECTION;
+                        // status may be from integrated TT
+                        status |= ehci_port_speed(ehci, temp);
                 }
+                if (temp & PORT_PE)
+                        status |= 1 << USB_PORT_FEAT_ENABLE;
+                if (temp & (PORT_SUSPEND|PORT_RESUME))
+                        status |= 1 << USB_PORT_FEAT_SUSPEND;
+                if (temp & PORT_OC)
+                        status |= 1 << USB_PORT_FEAT_OVER_CURRENT;
+                if (temp & PORT_RESET)
+                        status |= 1 << USB_PORT_FEAT_RESET;
+                if (temp & PORT_POWER)
+                        status |= 1 << USB_PORT_FEAT_POWER;
 
 #ifndef EHCI_VERBOSE_DEBUG
         if (status & ~0xffff)   /* only if wPortChange is interesting */