diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 0fffa5c..bde5a0b 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -56,6 +56,11 @@
 #define MMC_SDR_MODE		0
 #define MMC_1_2V_DDR_MODE	1
 #define MMC_1_8V_DDR_MODE	2
+
+	unsigned char	signal_voltage;		/* signalling voltage (1.8V or 3.3V) */
+
+#define MMC_SIGNAL_VOLTAGE_330	0
+#define MMC_SIGNAL_VOLTAGE_180	1
 };
 
 struct mmc_host_ops {
@@ -117,6 +122,8 @@
 
 	/* optional callback for HC quirks */
 	void	(*init_card)(struct mmc_host *host, struct mmc_card *card);
+
+	int	(*start_signal_voltage_switch)(struct mmc_host *host, struct mmc_ios *ios);
 };
 
 struct mmc_card;
@@ -173,6 +180,14 @@
 						/* DDR mode at 1.2V */
 #define MMC_CAP_POWER_OFF_CARD	(1 << 13)	/* Can power off after boot */
 #define MMC_CAP_BUS_WIDTH_TEST	(1 << 14)	/* CMD14/CMD19 bus width ok */
+#define MMC_CAP_UHS_SDR12	(1 << 15)	/* Host supports UHS SDR12 mode */
+#define MMC_CAP_UHS_SDR25	(1 << 16)	/* Host supports UHS SDR25 mode */
+#define MMC_CAP_UHS_SDR50	(1 << 17)	/* Host supports UHS SDR50 mode */
+#define MMC_CAP_UHS_SDR104	(1 << 18)	/* Host supports UHS SDR104 mode */
+#define MMC_CAP_UHS_DDR50	(1 << 19)	/* Host supports UHS DDR50 mode */
+#define MMC_CAP_SET_XPC_330	(1 << 20)	/* Host supports >150mA current at 3.3V */
+#define MMC_CAP_SET_XPC_300	(1 << 21)	/* Host supports >150mA current at 3.0V */
+#define MMC_CAP_SET_XPC_180	(1 << 22)	/* Host supports >150mA current at 1.8V */
 
 	mmc_pm_flag_t		pm_caps;	/* supported pm features */