Martin Fuzzey d0cc3d4100 USB: imx21-hcd accept arbitary transfer buffer alignement. ...

The hardware can only do DMA to 4 byte aligned addresses.
When this requirement is not met use PIO or a bounce buffer.

PIO is used when the buffer is small enough to directly
use the hardware data memory (2*maxpacket).

A bounce buffer is used for larger transfers.

Signed-off-by: Martin Fuzzey <mfuzzey@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2010-10-22 10:22:03 -07:00

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