Commit graph

2 commits

Author SHA1 Message Date
Michael Sevakis
2dd1f37a10 Fix f5a5b94 errors. Employ SW volume for select targets on SIM.
Onda VX747 sim was missing a limits #define; #include limits.h in
pcm_sw_volume.h.

Simply use the software volume control for the SIM volume control
rather than the SDL volume control when the target would have it
natively.

Change-Id: I8e924a2ff1b410f602452d2ea9b691efb82c931e
2013-04-11 19:00:23 -04:00
Michael Sevakis
f5a5b94686 Implement universal in-PCM-driver software volume control.
Implements double-buffered volume, balance and prescaling control in
the main PCM driver when HAVE_SW_VOLUME_CONTROL is defined ensuring
that all PCM is volume controlled and level changes are low in latency.

Supports -73 to +6 dB using a 15-bit factor so that no large-integer
math is needed.

Low-level hardware drivers do not have to implement it themselves but
parameters can be changed (currently defined in pcm-internal.h) to work
best with a particular SoC or to provide different volume ranges.

Volume and prescale calls should be made in the codec driver. It should
appear as a normal hardware interface. PCM volume calls expect .1 dB
units.

Change-Id: Idf6316a64ef4fb8abcede10707e1e6c6d01d57db
Reviewed-on: http://gerrit.rockbox.org/423
Reviewed-by: Michael Sevakis <jethead71@rockbox.org>
Tested-by: Michael Sevakis <jethead71@rockbox.org>
2013-04-11 22:55:16 +02:00