Add support for loading the SigmaDSP firmware using regmap. This allows us
to transparently use SPI or I2C as the transport protocol on devices which
support them.

For now we keep the old I2C support since we have one user of this which is not
straight forward to convert to regmap, due to variable length registers.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Move the structs and functions only used by SigmaDSP firmware loader itself
from the header to the C file.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

It has been pointed out previously, that the firmware subsystem is not the right
place for the SigmaDSP firmware loader. Furthermore the SigmaDSP is currently
only used in audio products and we are aiming for better integration into the
ASoC framework in the future, with support for ALSA controls for firmware
parameters and support dynamic power management as well. So the natural choice
for the SigmaDSP firmware loader is the ASoC subsystem.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Currently the SigmaDSP firmware loader only works correctly on little-endian
systems. Fix this by using the proper endianess conversion functions.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@kernel.org

The SigmaDSP firmware loader currently does not perform enough boundary size
checks when processing the firmware. As a result it is possible that a
malformed firmware can cause an out of bounds memory access.

This patch adds checks which ensure that both the action header and the payload
are completely inside the firmware data boundaries before processing them.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@kernel.org

Analog Devices' SigmaStudio can produce firmware blobs for devices with
these DSPs embedded (like some audio codecs).  Allow these device drivers
to easily parse and load them.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>