This issue acts as a place to collect and track leftovers and TODOs from the SPI rework done in #4780.

• Adapt pn532 (-> drivers/pn532: adapted to SPI interface changes #6478)
• Fix sensor driver lis3dh (-> drivers/lis3dh: fixed bug and simplified init() #6479, mulle: Use hardware CS for on-board LIS3DH #6572, periph/spi: Switching between CPOL=0,1 problems on Kinetis with software CS #6567)
• Fix nvram-spi
• Test peripheral driver on lpc11u34
• Test sensor driver adt7310
• Fix mrf24j40 connected to stm32fx boards (-> discussion in driver/mrf24j40: broken on stm32f4discovery #6519, fixed by stm32_common/spi: fix receive after transmit-only error #6764)
• Test ethernet driver encx24j600
• Test radio driver cc110x once debugged
• Adapt u8g2 package patch
• Check unrelated build errors emb6/lwip for msp430 platforms (->Make: buildtest: match exact board name #6483, tests/emb6: msb-430 insufficient memory #6482)

EDIT: Do the prformance analysis one SPI hardware testing is around

• Performance analysis/optimization for all SPI drivers
  • atmega_common
  • cc2538
  • kinetis_common
  • lpc11u34
  • lpc2387
  • msp430fxyz
  • nrf5x_common
  • sam21_common
  • sam3
  • stm32_common
• Problems when moving between polarity settings and using software CS on Kinetis (periph/spi: Switching between CPOL=0,1 problems on Kinetis with software CS #6567)
• Problems with hardware CS on Kinetis (@ 100kHz and 400kHz) (kinetis: Clean up SPI module power handling #9438)