[MMC] ios for mmc chip select

Adds a new ios for setting the chip select pin on MMC cards. Needed on
SD controllers which use this pin for other things and therefore cannot
have it pulled high at all times.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 3c59048..0a81659 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -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);
 }
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 9a0893f..30f68c0 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -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