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Welcome to the spi-bcm2835 wiki!

Observations on the situation with the current drivers (as of rpi-linux-690878e2)

• spi-bcm2708
• spi-bcm2835

Things to do

• import drivers from rpi-linux-690878e2
• instrument drivers with debugpins for analysis via a logic-analyzer
• implement loesi/9-bit mode in spi-bcm2835
  • note: needs a tester with a device!!!
• improvement of CS down to TX-delay due to interrupt latencies
• improvement of TX/RX to the max amount that the device says it can handle (deviate from the documentation for interrupt-driven)
• span the transfer of bytes in different spi_xfers in interrupt without any wakeup of a thread and the corresponding delays
• fix inverse polarity issues - this may mean also arbitrary CS support and not only CS0/CS1/CS2!
• support arbitrary Clock dividers - not only power of 2 as stated in the official documentation
• implement DMA transfers for longer chunks (maybe >64 bytes)
• full blown pipelined DMA implementation using dma-fragments
  • note to make this work efficiently we may need the "spi_optimize" in the core...
• upstream all of those
• get the official RPI kernel to support/use the spi-bcm2835 as their default SPI driver