sdhci: remove DMA capability check from controller's PCI Class reg

Many host controllers don't fully follow the PCI spec to claim
whether they support DMA in PCI class register. Leave the driver
to judge it from the Capability register, quirks and module parameter

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 317578d..866528c 100644 (file)
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1299,13 +1299,18 @@ static int __devinit sdhci_probe_slot(struct pci_dev *pdev, int slot)
                host->flags |= SDHCI_USE_DMA;
        } else if (chip->quirks & SDHCI_QUIRK_FORCE_DMA)
                host->flags |= SDHCI_USE_DMA;
-       else if ((pdev->class & 0x0000FF) != PCI_SDHCI_IFDMA)
-               DBG("Controller doesn't have DMA interface\n");
        else if (!(caps & SDHCI_CAN_DO_DMA))
                DBG("Controller doesn't have DMA capability\n");
        else
                host->flags |= SDHCI_USE_DMA;
 
+       if (((pdev->class & 0x0000FF) != PCI_SDHCI_IFDMA) &&
+               (host->flags & SDHCI_USE_DMA)) {
+               printk(KERN_WARNING "%s: Will use DMA "
+                       "mode even though HW doesn't fully "
+                       "claim to support it.\n", host->slot_descr);
+       }
+
        if (host->flags & SDHCI_USE_DMA) {
                if (pci_set_dma_mask(pdev, DMA_32BIT_MASK)) {
                        printk(KERN_WARNING "%s: No suitable DMA available. "