Re: [linux-pm] [PATCH v2] [RFC] ehci: Disable wake on overcurrent (WKOC_E) and disconnect (WKDISC_E)

["Du, Alek" <alek.du@intel.com>]

On Sat, 8 May 2010 10:00:59 +0800
"Du, Alek" <alek.du@intel.com> wrote:

> >On Fri, 7 May 2010, Du, Alek wrote:
> >
> >> Alan,
> >>
> >> As I tested, with the second patch, after entering phy low power mode, the
> >port cannot detect any USB devices that plugged in.
> >
> >Ooh, that's not good.  It almost violates the EHCI spec (see the last
> >line on p.60 in table 4.4).
> 

Alan,

The following patch (based on your previous two patches) works for me, could you
help to review and test on your machine? Basically, this will only affect those
"has_hostpc" HCDs.

Thanks,
Alek


diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 004379b..a2d2fbe 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -116,6 +116,17 @@ static void ehci_set_wakeup_flags(struct ehci_hcd *ehci)
                u32 __iomem     *reg = &ehci->regs->port_status[port];
                u32             t1 = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;
                u32             t2 = t1 & ~PORT_WAKE_BITS;
+               u32 __iomem     *hostpc_reg;
+               u32             temp;
+
+               /* clear phy low power mode first*/
+               if (ehci->has_hostpc) {
+                       hostpc_reg = (u32 __iomem *)((u8 *)ehci->regs
+                                       + HOSTPC0 + 4 * (port & 0xff));
+                       temp = ehci_readl(ehci, hostpc_reg);
+                       ehci_writel(ehci, temp & ~HOSTPC_PHCD, hostpc_reg);
+                       mdelay(5);
+               }
 
                /* only enable appropriate wake bits, otherwise the
                 * hardware can not go phy low power mode. If a race
@@ -131,6 +142,16 @@ static void ehci_set_wakeup_flags(struct ehci_hcd *ehci)
                                        port + 1, t1, t2);
                }
                ehci_writel(ehci, t2, reg);
+
+               /* enable phy low power mode again */
+               if (ehci->has_hostpc) {
+                       temp = ehci_readl(ehci, hostpc_reg);
+                       ehci_writel(ehci, temp | HOSTPC_PHCD, hostpc_reg);
+                       temp = ehci_readl(ehci, hostpc_reg);
+                       ehci_dbg(ehci, "Port%d phy low pwr mode %s\n",
+                                       port, (temp & HOSTPC_PHCD) ?
+                                       "succeeded" : "failed");
+               }
        }
 }
 
@@ -217,6 +238,14 @@ static int ehci_bus_suspend (struct usb_hcd *hcd)
                                u32 __iomem     *hostpc_reg;
                                u32             t3;
 
+                               if (t1 & PORT_CONNECT) {
+                                       t2 |= PORT_WKOC_E | PORT_WKDISC_E;
+                                       t2 &= ~PORT_WKCONN_E;
+                               } else {
+                                       t2 |= PORT_WKOC_E | PORT_WKCONN_E;
+                                       t2 &= ~PORT_WKDISC_E;
+                               }
+                               ehci_writel(ehci, t2, reg);
                                hostpc_reg = (u32 __iomem *)((u8 *)ehci->regs
                                        + HOSTPC0 + 4 * (port & 0xff));
                                spin_unlock_irq(&ehci->lock);