[MMC] sdhci: more DMA capabilities tests

Properly test for controller interface to see if it's DMA capable.  As many
controllers are misconfigured in this regard, also add debug parameters to
force DMA support either way.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/mmc/sdhci.h b/drivers/mmc/sdhci.h
index 758cf1c..8111fa3 100644
--- a/drivers/mmc/sdhci.h
+++ b/drivers/mmc/sdhci.h
@@ -12,6 +12,10 @@
  * PCI registers
  */
 
+#define PCI_SDHCI_IFPIO			0x00
+#define PCI_SDHCI_IFDMA			0x01
+#define PCI_SDHCI_IFVENDOR		0x02
+
 #define PCI_SLOT_INFO			0x40	/* 8 bits */
 #define  PCI_SLOT_INFO_SLOTS(x)		((x >> 4) & 7)
 #define  PCI_SLOT_INFO_FIRST_BAR_MASK	0x07