kconfig

linux 内核源代码

#
# 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.