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Commit 6e16edfe authored by Anand Gadiyar's avatar Anand Gadiyar Committed by Felipe Balbi
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usb: musb: fail unaligned DMA transfers on v1.8 and above



The Inventra DMA engine in version 1.8 and later of the MUSB
controller cannot handle DMA addresses that are not aligned
to a 4 byte boundary. It ends up ignoring the last two bits
programmed in the DMA_ADDR register. This is a deliberate
design change in the controller and is documented in the
programming guide.

Earlier versions of the controller could handle these
accesses just fine.

Fail dma_channel_program if we see an unaligned address when
using the newer controllers, so that the caller can carry out
the transfer using PIO mode.
(Current callers already have this backup path in place).

Signed-off-by: default avatarAnand Gadiyar <gadiyar@ti.com>
Tested-by: default avatarMing Lei <tom.leiming@gmail.com>
Cc: Ajay Kumar Gupta <ajay.gupta@ti.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: default avatarFelipe Balbi <balbi@ti.com>
parent 07397021
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