mmc: mxs-mmc: add mmc host driver for i.MX23/28

This adds the mmc host driver for Freescale MXS-based SoC i.MX23/28.
The driver calls into mxs-dma via generic dmaengine api for both pio
and data transfer.

Thanks Chris Ball for the indentation patch.

Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 54b7bd5..398d7d5 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -319,6 +319,15 @@
 
 	  If unsure, say N.
 
+config MMC_MXS
+	tristate "Freescale MXS Multimedia Card Interface support"
+	depends on ARCH_MXS && MXS_DMA
+	help
+	  This selects the Freescale SSP MMC controller found on MXS based
+	  platforms like mx23/28.
+
+	  If unsure, say N.
+
 config MMC_TIFM_SD
 	tristate "TI Flash Media MMC/SD Interface support  (EXPERIMENTAL)"
 	depends on EXPERIMENTAL && PCI