The WS2812 is very common in LED strips as it is an integrated
controller and LED. It is driven by a single data line, but
the timing requirements can be met by using most SPI controllers
and the use of DMA.
This driver has been validated on the nRF52 arch both with a
single LED and a strip of 144.
Signed-off-by: Brennan Ashton <bashton@brennanashton.com>
configs/stm32f4discovery/src: Add board support to MAX7219 as numeric display controller
drivers/leds/max7219.c: Add support to MAX7219 to control 7-segment displays
