DMA + PIO

configname: CONFIG_B43LEGACY_DMA_AND_PIO_MODE

Broadcom 43xx-legacy data transfer mode
└─>DMA + PIO
In linux kernel since version 2.6.24 (release Date: 2008-01-24)  
Include both, Direct Memory Access (DMA) and Programmed I/O (PIO)
data transfer modes. The mode actually used is selectable through
the module parameter "pio". With pio=0 as a module parameter, the
default DMA is used, otherwise PIO is used.

If unsure, choose this option.