i: do not use temporary buffer if no transmit data provided
   spi: davinci: always start receive DMA
   spi: davinci: use edma_write_slot() to setup EDMA PaRAM slot
   spi: davinci: fix DMA event generation stoppage
   spi: davinci: fix EDMA CC errors at end of transfers
   spi: davinci: handle DMA completion errors correctly
   spi: davinci: remove usage of additional completion variables for DMA
   spi: davinci: let DMA operation be specified on per-device basis
   spi: davinci: remove non-useful "clk_internal" platform data
   spi: davinci: enable and power-up SPI only when required
   spi: davinci: setup the driver owner
   spi: davinci: add additional comments
   spi: davinci: add EF Johnson Technologies copyright
   spi: davinci: removed unused #defines
   spi: davinci: remove unnecessary typecast
   spi: davinci: do not treat Tx interrupt being set as error
   spi: davinci: do not allocate DMA channels during SPI device setup
   spi: davinci: remove unnecessary private data member 'region_size'
   spi: davinci: shorten variable names
   spi: davinci: kconfig: add manufacturer name to prompt string