mmc: core: Add cache control for eMMC4.5 device

This patch adds cache feature of eMMC4.5 Spec.
If device supports cache capability, host can utilize some specific
operations.

Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index 8a05a21..160e4c5 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -270,6 +270,8 @@
  * EXT_CSD fields
  */
 
+#define EXT_CSD_FLUSH_CACHE		32      /* W */
+#define EXT_CSD_CACHE_CTRL		33      /* R/W */
 #define EXT_CSD_POWER_OFF_NOTIFICATION	34	/* R/W */
 #define EXT_CSD_GP_SIZE_MULT		143	/* R/W */
 #define EXT_CSD_PARTITION_ATTRIBUTE	156	/* R/W */
@@ -308,6 +310,7 @@
 #define EXT_CSD_PWR_CL_DDR_52_360	239	/* RO */
 #define EXT_CSD_POWER_OFF_LONG_TIME	247	/* RO */
 #define EXT_CSD_GENERIC_CMD6_TIME	248	/* RO */
+#define EXT_CSD_CACHE_SIZE		249	/* RO, 4 bytes */
 
 /*
  * EXT_CSD field definitions