Signed-off-by: Jaroslav Kysela <perex@perex.cz>

Added the definition of TLV dB range compound.  It contains one or
more dB-range or linear-volume TLV entries with min/max ranges.
Used for volume controls with non-linear curves.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

Added the definition of linear volume TLV type.
Some DSP chips and codecs (e.g. AK codec) use linear volume control.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

This patch implements a TLV mechanism to transfer an additional information
like dB scale to the user space. The types might be extended in future.
Acked-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>