|  | # | 
|  | # MMC/SD card drivers | 
|  | # | 
|  |  | 
|  | comment "MMC/SD Card Drivers" | 
|  |  | 
|  | config MMC_BLOCK | 
|  | tristate "MMC block device driver" | 
|  | depends on BLOCK | 
|  | default y | 
|  | help | 
|  | Say Y here to enable the MMC block device driver support. | 
|  | This provides a block device driver, which you can use to | 
|  | mount the filesystem. Almost everyone wishing MMC support | 
|  | should say Y or M here. | 
|  |  | 
|  | config MMC_BLOCK_BOUNCE | 
|  | bool "Use bounce buffer for simple hosts" | 
|  | depends on MMC_BLOCK | 
|  | default y | 
|  | help | 
|  | SD/MMC is a high latency protocol where it is crucial to | 
|  | send large requests in order to get high performance. Many | 
|  | controllers, however, are restricted to continuous memory | 
|  | (i.e. they can't do scatter-gather), something the kernel | 
|  | rarely can provide. | 
|  |  | 
|  | Say Y here to help these restricted hosts by bouncing | 
|  | requests back and forth from a large buffer. You will get | 
|  | a big performance gain at the cost of up to 64 KiB of | 
|  | physical memory. | 
|  |  | 
|  | If unsure, say Y here. | 
|  |  | 
|  | config SDIO_UART | 
|  | tristate "SDIO UART/GPS class support" | 
|  | depends on MMC | 
|  | help | 
|  | SDIO function driver for SDIO cards that implements the UART | 
|  | class, as well as the GPS class which appears like a UART. | 
|  |  |