[PATCH] sd: SD 4-bit bus

Infrastructure for 4-bit bus transfers with SD cards.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 8c5f713..6014160 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -57,6 +57,11 @@
 #define MMC_POWER_OFF		0
 #define MMC_POWER_UP		1
 #define MMC_POWER_ON		2
+
+	unsigned char	bus_width;		/* data bus width */
+
+#define MMC_BUS_WIDTH_1		0
+#define MMC_BUS_WIDTH_4		2
 };
 
 struct mmc_host_ops {
@@ -77,6 +82,10 @@
 	unsigned int		f_max;
 	u32			ocr_avail;
 
+	unsigned long		caps;		/* Host capabilities */
+
+#define MMC_CAP_4_BIT_DATA	(1 << 0)	/* Can the host do 4 bit transfers */
+
 	/* host specific block data */
 	unsigned int		max_seg_size;	/* see blk_queue_max_segment_size */
 	unsigned short		max_hw_segs;	/* see blk_queue_max_hw_segments */
diff --git a/include/linux/mmc/protocol.h b/include/linux/mmc/protocol.h
index 8963428..f819cae 100644
--- a/include/linux/mmc/protocol.h
+++ b/include/linux/mmc/protocol.h
@@ -236,5 +236,12 @@
 #define CSD_SPEC_VER_2      2           /* Implements system specification 2.0 - 2.2 */
 #define CSD_SPEC_VER_3      3           /* Implements system specification 3.1 */
 
+
+/*
+ * SD bus widths
+ */
+#define SD_BUS_WIDTH_1      0
+#define SD_BUS_WIDTH_4      2
+
 #endif  /* MMC_MMC_PROTOCOL_H */