# # SPI driver configuration # # NOTE: the reason this doesn't show SPI slave support is mostly that # nobody's needed a slave side API yet. The master-role API is not # fully appropriate there, so it'd need some thought to do well. # menu "SPI support" config SPI bool "SPI support" help The "Serial Peripheral Interface" is a low level synchronous protocol. Chips that support SPI can have data transfer rates up to several tens of Mbit/sec. Chips are addressed with a controller and a chipselect. Most SPI slaves don't support dynamic device discovery; some are even write-only or read-only. SPI is widely used by microcontollers to talk with sensors, eeprom and flash memory, codecs and various other controller chips, analog to digital (and d-to-a) converters, and more. MMC and SD cards can be accessed using SPI protocol; and for DataFlash cards used in MMC sockets, SPI must always be used. SPI is one of a family of similar protocols using a four wire interface (select, clock, data in, data out) including Microwire (half duplex), SSP, SSI, and PSP. This driver framework should work with most such devices and controllers. config SPI_DEBUG boolean "Debug support for SPI drivers" depends on SPI && DEBUG_KERNEL help Say "yes" to enable debug messaging (like dev_dbg and pr_debug), sysfs, and debugfs support in SPI controller and protocol drivers. # # MASTER side ... talking to discrete SPI slave chips including microcontrollers # config SPI_MASTER # boolean "SPI Master Support" boolean default SPI help If your system has an master-capable SPI controller (which provides the clock and chipselect), you can enable that controller and the protocol drivers for the SPI slave chips that are connected. comment "SPI Master Controller Drivers" depends on SPI_MASTER config SPI_BITBANG tristate "Bitbanging SPI master" depends on SPI_MASTER && EXPERIMENTAL help With a few GPIO pins, your system can bitbang the SPI protocol. Select this to get SPI support through I/O pins (GPIO, parallel port, etc). Or, some systems' SPI master controller drivers use this code to manage the per-word or per-transfer accesses to the hardware shift registers. This is library code, and is automatically selected by drivers that need it. You only need to select this explicitly to support driver modules that aren't part of this kernel tree. config SPI_BUTTERFLY tristate "Parallel port adapter for AVR Butterfly (DEVELOPMENT)" depends on SPI_MASTER && PARPORT && EXPERIMENTAL select SPI_BITBANG help This uses a custom parallel port cable to connect to an AVR Butterfly , an inexpensive battery powered microcontroller evaluation board. This same cable can be used to flash new firmware. # # Add new SPI master controllers in alphabetical order above this line # # # There are lots of SPI device types, with sensors and memory # being probably the most widely used ones. # comment "SPI Protocol Masters" depends on SPI_MASTER # # Add new SPI protocol masters in alphabetical order above this line # # (slave support would go here) endmenu # "SPI support"