Index: linux/drivers/mmc/mmc.c
===================================================================
--- linux/drivers/mmc/mmc.c	(revision 151)
+++ linux/drivers/mmc/mmc.c	(working copy)
@@ -457,6 +457,11 @@
 {
 	struct mmc_command cmd;
 
+	host->ios.chip_select = MMC_CS_HIGH;
+	host->ops->set_ios(host, &host->ios);
+
+	mmc_delay(1);
+
 	cmd.opcode = MMC_GO_IDLE_STATE;
 	cmd.arg = 0;
 	cmd.flags = MMC_RSP_NONE;
@@ -464,6 +469,11 @@
 	mmc_wait_for_cmd(host, &cmd, 0);
 
 	mmc_delay(1);
+
+	host->ios.chip_select = MMC_CS_DONTCARE;
+	host->ops->set_ios(host, &host->ios);
+
+	mmc_delay(1);
 }
 
 /*
@@ -475,6 +485,7 @@
 
 	host->ios.vdd = bit;
 	host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
+	host->ios.chip_select = MMC_CS_DONTCARE;
 	host->ios.power_mode = MMC_POWER_UP;
 	host->ops->set_ios(host, &host->ios);
 
@@ -492,6 +503,7 @@
 	host->ios.clock = 0;
 	host->ios.vdd = 0;
 	host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
+	host->ios.chip_select = MMC_CS_DONTCARE;
 	host->ios.power_mode = MMC_POWER_OFF;
 	host->ops->set_ios(host, &host->ios);
 }
Index: linux/include/linux/mmc/host.h
===================================================================
--- linux/include/linux/mmc/host.h	(revision 151)
+++ linux/include/linux/mmc/host.h	(working copy)
@@ -46,6 +46,12 @@
 #define MMC_BUSMODE_OPENDRAIN	1
 #define MMC_BUSMODE_PUSHPULL	2
 
+	unsigned char	chip_select;		/* SPI chip select */
+
+#define MMC_CS_DONTCARE		0
+#define MMC_CS_HIGH		1
+#define MMC_CS_LOW		2
+
 	unsigned char	power_mode;		/* power supply mode */
 
 #define MMC_POWER_OFF		0