SPI drivers relationship ? - Raspberry Pi Forums

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hi,

trying catch great work done martin , others.

missing knowledge relationship between drivers :
* https://github.com/raspberrypi/linux/bl ... /spi/spi.c
* https://github.com/raspberrypi/linux/bl ... i/spidev.c
* https://github.com/raspberrypi/linux/bl ... -bcm2708.c

have several spi slave specific drivers. fit in?

thanks. regards, arjan

  • spi.c: generic spi abstraction layer of linux acts middleware between low level driver , device driver(=device connected system on spi bus)
  • spi-bcm2708.c: low level driver talks rpi spi hardware sending-receiving bytes spi bus (you need 1 of per physical board
  • spidev.c: 1 of many device drivers (other examples: mmc.c, mcp251x.c, enc28j60.c,...) specific driver allows userspace send arbitrary data device on spi exposing interface in /sys (similar gpio driver). allows custom user-space device driver maintained outside of kernel. not highest performance interface, can helpfull rapid prototyping. see: http://www.kernel.org/doc/documentation/spi/spidev how use it...
hope answers question...

martin


raspberrypi



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