From: Alan Cox <alan@lxorguk.ukuu.org.uk>
Date: Thu, 24 Jul 2008 16:18:38 +0000 (+0100)
Subject: PCI: add D3 power state avoidance quirk
X-Git-Tag: v2.6.27-rc1~3^2~2
X-Git-Url: http://www.pilppa.org/gitweb/gitweb.cgi?a=commitdiff_plain;h=979b1791e5b8f8b556faeec4c48339e7ed63af9f;p=linux-2.6-omap-h63xx.git

PCI: add D3 power state avoidance quirk

Libata has some hacks to deal with certain controllers going silly in D3
state. The right way to handle this is to keep a PCI device flag for
such devices. That can then be generalised for no ATA devices with power
problems.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index c95f77d6571..0a3d856833f 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -572,6 +572,10 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
 		if (!ret)
 			pci_update_current_state(dev);
 	}
+	/* This device is quirked not to be put into D3, so
+	   don't put it in D3 */
+	if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
+		return 0;
 
 	error = pci_raw_set_power_state(dev, state);
 
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 12d489395fa..0fb36507428 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -923,6 +923,19 @@ static void __init quirk_ide_samemode(struct pci_dev *pdev)
 }
 DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_10, quirk_ide_samemode);
 
+/*
+ * Some ATA devices break if put into D3
+ */
+
+static void __devinit quirk_no_ata_d3(struct pci_dev *pdev)
+{
+	/* Quirk the legacy ATA devices only. The AHCI ones are ok */
+	if ((pdev->class >> 8) == PCI_CLASS_STORAGE_IDE)
+		pdev->dev_flags |= PCI_DEV_FLAGS_NO_D3;
+}
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, PCI_ANY_ID, quirk_no_ata_d3);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_ATI, PCI_ANY_ID, quirk_no_ata_d3);
+
 /* This was originally an Alpha specific thing, but it really fits here.
  * The i82375 PCI/EISA bridge appears as non-classified. Fix that.
  */
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 1d296d31abe..825be3878f6 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -124,6 +124,8 @@ enum pci_dev_flags {
 	 * generation too.
 	 */
 	PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG = (__force pci_dev_flags_t) 1,
+	/* Device configuration is irrevocably lost if disabled into D3 */
+	PCI_DEV_FLAGS_NO_D3 = (__force pci_dev_flags_t) 2,
 };
 
 typedef unsigned short __bitwise pci_bus_flags_t;