USB: add NO_D3_DURING_SLEEP flag and revert 151b61284776be2

commit c2fb8a3fa25513de8fedb38509b1f15a5bbee47b upstream.

This patch (as1558) fixes a problem affecting several ASUS computers:
The machine crashes or corrupts memory when going into suspend if the
ehci-hcd driver is bound to any controllers.  Users have been forced
to unbind or unload ehci-hcd before putting their systems to sleep.

After extensive testing, it was determined that the machines don't
like going into suspend when any EHCI controllers are in the PCI D3
power state.  Presumably this is a firmware bug, but there's nothing
we can do about it except to avoid putting the controllers in D3
during system sleep.

The patch adds a new flag to indicate whether the problem is present,
and avoids changing the controller's power state if the flag is set.
Runtime suspend is unaffected; this matters only for system suspend.
However as a side effect, the controller will not respond to remote
wakeup requests while the system is asleep.  Hence USB wakeup is not
functional -- but of course, this is already true in the current state
of affairs.

A similar patch has already been applied as commit
151b61284776be2d6f02d48c23c3625678960b97 (USB: EHCI: fix crash during
suspend on ASUS computers).  The patch supersedes that one and reverts
it.  There are two differences:

	The old patch added the flag at the USB level; this patch
	adds it at the PCI level.

	The old patch applied to all chipsets with the same vendor,
	subsystem vendor, and product IDs; this patch makes an
	exception for a known-good system (based on DMI information).

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Dâniel Fraga <fragabr@gmail.com>
Tested-by: Andrey Rahmatullin <wrar@wrar.name>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 31 insertions, 0 deletions

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index d549bbc93cdd..bf401aead873 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1682,6 +1682,11 @@ int pci_prepare_to_sleep(struct pci_dev *dev)
 	if (target_state == PCI_POWER_ERROR)
 		return -EIO;
 
+	/* Some devices mustn't be in D3 during system sleep */
+	if (target_state == PCI_D3hot &&
+			(dev->dev_flags & PCI_DEV_FLAGS_NO_D3_DURING_SLEEP))
+		return 0;
+
 	pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev));
 
 	error = pci_set_power_state(dev, target_state);
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index a6b07ddad715..975af4353e73 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -2856,6 +2856,32 @@ static void __devinit disable_igfx_irq(struct pci_dev *dev)
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x0102, disable_igfx_irq);
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x010a, disable_igfx_irq);
 
+/*
+ * The Intel 6 Series/C200 Series chipset's EHCI controllers on many
+ * ASUS motherboards will cause memory corruption or a system crash
+ * if they are in D3 while the system is put into S3 sleep.
+ */
+static void __devinit asus_ehci_no_d3(struct pci_dev *dev)
+{
+	const char *sys_info;
+	static const char good_Asus_board[] = "P8Z68-V";
+
+	if (dev->dev_flags & PCI_DEV_FLAGS_NO_D3_DURING_SLEEP)
+		return;
+	if (dev->subsystem_vendor != PCI_VENDOR_ID_ASUSTEK)
+		return;
+	sys_info = dmi_get_system_info(DMI_BOARD_NAME);
+	if (sys_info && memcmp(sys_info, good_Asus_board,
+			sizeof(good_Asus_board) - 1) == 0)
+		return;
+
+	dev_info(&dev->dev, "broken D3 during system sleep on ASUS\n");
+	dev->dev_flags |= PCI_DEV_FLAGS_NO_D3_DURING_SLEEP;
+	device_set_wakeup_capable(&dev->dev, false);
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x1c26, asus_ehci_no_d3);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x1c2d, asus_ehci_no_d3);
+
 static void pci_do_fixups(struct pci_dev *dev, struct pci_fixup *f,
 			  struct pci_fixup *end)
 {