OHCI: work around for nVidia shutdown problem

[ upstream commit 5f528de0ef9b3e092e276d95930830b847b33dc4 ]
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commit 3df7169e73fc1d71a39cffeacc969f6840cdf52b upstream.

This patch (as1417) fixes a problem affecting some (or all) nVidia
chipsets.  When the computer is shut down, the OHCI controllers
continue to power the USB buses and evidently they drive a Reset
signal out all their ports.  This prevents attached devices from going
to low power.  Mouse LEDs stay on, for example, which is disconcerting
for users and a drain on laptop batteries.

The fix involves leaving each OHCI controller in the OPERATIONAL state
during system shutdown rather than putting it in the RESET state.
Although this nominally means the controller is running, in fact it's
not doing very much since all the schedules are all disabled.  However
there is ongoing DMA to the Host Controller Communications Area, so
the patch also disables the bus-master capability of all PCI USB
controllers after the shutdown routine runs.

The fix is applied only to nVidia-based PCI OHCI controllers, so it
shouldn't cause problems on systems using other hardware.  As an added
safety measure, in case the kernel encounters one of these running
controllers during boot, the patch changes quirk_usb_handoff_ohci()
(which runs early on during PCI discovery) to reset the controller
before anything bad can happen.

Reported-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
CC: David Brownell <david-b@pacbell.net>
Tested-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c
index 1cf2d1e79a5c2a12ff64f6a6ba8329c8008aff04..3667660aee986a6bcd6cd8083d5aff58b8b17f05 100644 (file)
--- a/drivers/usb/core/hcd-pci.c
+++ b/drivers/usb/core/hcd-pci.c
@@ -317,8 +317,10 @@ void usb_hcd_pci_shutdown(struct pci_dev *dev)
        if (!hcd)
                return;
 
-       if (hcd->driver->shutdown)
+       if (hcd->driver->shutdown) {
                hcd->driver->shutdown(hcd);
+               pci_disable_device(dev);
+       }
 }
 EXPORT_SYMBOL_GPL(usb_hcd_pci_shutdown);
 

diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
index fc576557d8a5d2520aee7e6edcbafb17e4701de8..cc5a8e6db8cbec824018112690c950bb3ac479d7 100644 (file)
--- a/drivers/usb/host/ohci-hcd.c
+++ b/drivers/usb/host/ohci-hcd.c
@@ -398,7 +398,14 @@ ohci_shutdown (struct usb_hcd *hcd)
 
        ohci = hcd_to_ohci (hcd);
        ohci_writel (ohci, OHCI_INTR_MIE, &ohci->regs->intrdisable);
-       ohci_usb_reset (ohci);
+       ohci->hc_control = ohci_readl(ohci, &ohci->regs->control);
+
+       /* If the SHUTDOWN quirk is set, don't put the controller in RESET */
+       ohci->hc_control &= (ohci->flags & OHCI_QUIRK_SHUTDOWN ?
+                       OHCI_CTRL_RWC | OHCI_CTRL_HCFS :
+                       OHCI_CTRL_RWC);
+       ohci_writel(ohci, ohci->hc_control, &ohci->regs->control);
+
        /* flush the writes */
        (void) ohci_readl (ohci, &ohci->regs->control);
 }

diff --git a/drivers/usb/host/ohci-pci.c b/drivers/usb/host/ohci-pci.c
index b8a1148f248e4faeb404fbcedf76e6c36d0e6ea2..948a353351503f82d551992112b0555a7e6b27ec 100644 (file)
--- a/drivers/usb/host/ohci-pci.c
+++ b/drivers/usb/host/ohci-pci.c
@@ -201,6 +201,20 @@ static int ohci_quirk_amd700(struct usb_hcd *hcd)
        return 0;
 }
 
+/* nVidia controllers continue to drive Reset signalling on the bus
+ * even after system shutdown, wasting power.  This flag tells the
+ * shutdown routine to leave the controller OPERATIONAL instead of RESET.
+ */
+static int ohci_quirk_nvidia_shutdown(struct usb_hcd *hcd)
+{
+       struct ohci_hcd *ohci = hcd_to_ohci(hcd);
+
+       ohci->flags |= OHCI_QUIRK_SHUTDOWN;
+       ohci_dbg(ohci, "enabled nVidia shutdown quirk\n");
+
+       return 0;
+}
+
 /*
  * The hardware normally enables the A-link power management feature, which
  * lets the system lower the power consumption in idle states.
@@ -332,6 +346,10 @@ static const struct pci_device_id ohci_pci_quirks[] = {
                PCI_DEVICE(PCI_VENDOR_ID_ATI, 0x4399),
                .driver_data = (unsigned long)ohci_quirk_amd700,
        },
+       {
+               PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID),
+               .driver_data = (unsigned long) ohci_quirk_nvidia_shutdown,
+       },
 
        /* FIXME for some of the early AMD 760 southbridges, OHCI
         * won't work at all.  blacklist them.

diff --git a/drivers/usb/host/ohci.h b/drivers/usb/host/ohci.h
index 5bf15fed0d9fcd4f4654bb51c7ae38ea82cf905c..51facb985c847801ca3af267aac4887293e18ad3 100644 (file)
--- a/drivers/usb/host/ohci.h
+++ b/drivers/usb/host/ohci.h
@@ -403,6 +403,7 @@ struct ohci_hcd {
 #define        OHCI_QUIRK_HUB_POWER    0x100                   /* distrust firmware power/oc setup */
 #define        OHCI_QUIRK_AMD_ISO      0x200                   /* ISO transfers*/
 #define        OHCI_QUIRK_AMD_PREFETCH 0x400                   /* pre-fetch for ISO transfer */
+#define        OHCI_QUIRK_SHUTDOWN     0x800                   /* nVidia power bug */
        // there are also chip quirks/bugs in init logic
 
        struct work_struct      nec_work;       /* Worker for NEC quirk */

diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index 83b5f9cea85ac9f43af8d3b1eb87a259517cc05c..464ed977b45d9d0388af38e565fb0fe07966c712 100644 (file)
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -169,6 +169,7 @@ static int __devinit mmio_resource_enabled(struct pci_dev *pdev, int idx)
 static void __devinit quirk_usb_handoff_ohci(struct pci_dev *pdev)
 {
        void __iomem *base;
+       u32 control;
 
        if (!mmio_resource_enabled(pdev, 0))
                return;
@@ -177,10 +178,14 @@ static void __devinit quirk_usb_handoff_ohci(struct pci_dev *pdev)
        if (base == NULL)
                return;
 
+       control = readl(base + OHCI_CONTROL);
+
 /* On PA-RISC, PDC can leave IR set incorrectly; ignore it there. */
-#ifndef __hppa__
-{
-       u32 control = readl(base + OHCI_CONTROL);
+#ifdef __hppa__
+#define        OHCI_CTRL_MASK          (OHCI_CTRL_RWC | OHCI_CTRL_IR)
+#else
+#define        OHCI_CTRL_MASK          OHCI_CTRL_RWC
+
        if (control & OHCI_CTRL_IR) {
                int wait_time = 500; /* arbitrary; 5 seconds */
                writel(OHCI_INTR_OC, base + OHCI_INTRENABLE);
@@ -194,13 +199,12 @@ static void __devinit quirk_usb_handoff_ohci(struct pci_dev *pdev)
                        dev_warn(&pdev->dev, "OHCI: BIOS handoff failed"
                                        " (BIOS bug?) %08x\n",
                                        readl(base + OHCI_CONTROL));
-
-               /* reset controller, preserving RWC */
-               writel(control & OHCI_CTRL_RWC, base + OHCI_CONTROL);
        }
-}
 #endif
 
+       /* reset controller, preserving RWC (and possibly IR) */
+       writel(control & OHCI_CTRL_MASK, base + OHCI_CONTROL);
+
        /*
         * disable interrupts
         */