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5e71b7a64c
The old limit of number of minor numbers per mmcblk device was hardcoded at 8. This isn't enough for some of the more elaborate partitioning schemes, for example those used by Chrome OS. Since there might be a bunch of systems out there with static /dev contents that relies on the old numbering scheme, let's make it a build-time option with the default set to the previous 8. Also provide a boot/modprobe-time parameter to override the config default: mmcblk.perdev_minors. Signed-off-by: Olof Johansson <olof@lixom.net> Cc: Mandeep Baines <msb@chromium.org> Cc: <linux-mmc@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Chris Ball <cjb@laptop.org>
70 lines
2.1 KiB
Plaintext
70 lines
2.1 KiB
Plaintext
#
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# MMC/SD card drivers
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#
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comment "MMC/SD/SDIO Card Drivers"
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config MMC_BLOCK
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tristate "MMC block device driver"
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depends on BLOCK
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default y
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help
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Say Y here to enable the MMC block device driver support.
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This provides a block device driver, which you can use to
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mount the filesystem. Almost everyone wishing MMC support
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should say Y or M here.
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config MMC_BLOCK_MINORS
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int "Number of minors per block device"
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range 4 256
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default 8
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help
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Number of minors per block device. One is needed for every
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partition on the disk (plus one for the whole disk).
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Number of total MMC minors available is 256, so your number
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of supported block devices will be limited to 256 divided
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by this number.
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Default is 8 to be backwards compatible with previous
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hardwired device numbering.
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If unsure, say 8 here.
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config MMC_BLOCK_BOUNCE
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bool "Use bounce buffer for simple hosts"
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depends on MMC_BLOCK
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default y
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help
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SD/MMC is a high latency protocol where it is crucial to
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send large requests in order to get high performance. Many
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controllers, however, are restricted to continuous memory
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(i.e. they can't do scatter-gather), something the kernel
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rarely can provide.
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Say Y here to help these restricted hosts by bouncing
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requests back and forth from a large buffer. You will get
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a big performance gain at the cost of up to 64 KiB of
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physical memory.
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If unsure, say Y here.
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config SDIO_UART
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tristate "SDIO UART/GPS class support"
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help
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SDIO function driver for SDIO cards that implements the UART
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class, as well as the GPS class which appears like a UART.
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config MMC_TEST
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tristate "MMC host test driver"
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default n
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help
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Development driver that performs a series of reads and writes
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to a memory card in order to expose certain well known bugs
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in host controllers. The tests are executed by writing to the
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"test" file in sysfs under each card. Note that whatever is
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on your card will be overwritten by these tests.
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This driver is only of interest to those developing or
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testing a host driver. Most people should say N here.
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