mmc: sdhci-pci: add quirks for broken MSI on O2Micro controllers

MSI on my O2Micro OZ600 SD card reader is broken.  This patch adds a quirk
to disable MSI on these controllers.

Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

2 files changed, 5 insertions, 1 deletions

diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
index fbbebe251e01..9303f7fc1e68 100644
--- a/drivers/mmc/host/sdhci-pci.c
+++ b/drivers/mmc/host/sdhci-pci.c
@@ -561,6 +561,7 @@ static int jmicron_resume(struct sdhci_pci_chip *chip)
 
 static const struct sdhci_pci_fixes sdhci_o2 = {
         .probe          = o2_probe,
+        .quirks2        = SDHCI_QUIRK2_BROKEN_MSI,
 };
 
 static const struct sdhci_pci_fixes sdhci_jmicron = {
@@ -1418,7 +1419,8 @@ static int __devinit sdhci_pci_probe(struct pci_dev *pdev,
 
         slots = chip->num_slots;        /* Quirk may have changed this */
 
-        pci_enable_msi(pdev);
+        if (!(chip->quirks2 & SDHCI_QUIRK2_BROKEN_MSI))
+                pci_enable_msi(pdev);
 
         for (i = 0; i < slots; i++) {
                 slot = sdhci_pci_probe_slot(pdev, chip, first_bar, i);
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index e9051e1cb1ce..9752fe434ae9 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -91,6 +91,8 @@ struct sdhci_host {
         unsigned int quirks2;   /* More deviations from spec. */
 
 #define SDHCI_QUIRK2_HOST_OFF_CARD_ON                   (1<<0)
+/* broken MSI Interrupts */
+#define SDHCI_QUIRK2_BROKEN_MSI                         (1<<1)
 
         int irq;                /* Device IRQ */
         void __iomem *ioaddr;   /* Mapped address */