mmc: require explicit support for high-speed

The new high-speed timings are similar to each other and the old
system, but not identical. And although things "just work" most of
the time, sometimes it does not. So we need to start marking which
hosts are known to fully comply with the new timings.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

include/linux/mmc/host.h

@@ -62,6 +62,12 @@ struct mmc_ios {
 
 #define MMC_BUS_WIDTH_1		0
 #define MMC_BUS_WIDTH_4		2
+
+	unsigned char	timing;			/* timing specification used */
+
+#define MMC_TIMING_LEGACY	0
+#define MMC_TIMING_MMC_HS	1
+#define MMC_TIMING_SD_HS	2
 };
 
 struct mmc_host_ops {
@@ -87,6 +93,8 @@ struct mmc_host {
 #define MMC_CAP_4_BIT_DATA	(1 << 0)	/* Can the host do 4 bit transfers */
 #define MMC_CAP_MULTIWRITE	(1 << 1)	/* Can accurately report bytes sent to card on error */
 #define MMC_CAP_BYTEBLOCK	(1 << 2)	/* Can do non-log2 block sizes */
+#define MMC_CAP_MMC_HIGHSPEED	(1 << 3)	/* Can do MMC high-speed timing */
+#define MMC_CAP_SD_HIGHSPEED	(1 << 4)	/* Can do SD high-speed timing */
 
 	/* host specific block data */
 	unsigned int		max_seg_size;	/* see blk_queue_max_segment_size */