ASoC: uniphier: add support for multichannel output

This patch adds multichannel PCM output support for LD11/LD20.
Currently driver tested and supported only 2ch, 6ch, and 8ch.

Signed-off-by: Katsuhiro Suzuki <suzuki.katsuhiro@socionext.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

ASoC: uniphier: add digital output volume for UniPhier sound system

This patch adds controllers for digital volume of PCM output. Volume
effects simply linear, not dB scale as follows:
Gained PCM = Original * 0x4000 / Volume

The value range of volume is from 0x0001 to 0xffff. 0x0000 works as
mute. Initial value is 0x4000 (+0dB).

Signed-off-by: Katsuhiro Suzuki <suzuki.katsuhiro@socionext.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

ASoC: uniphier: remove boilerplate from lisence comment

This patch removes boilerplate of GPLv2, use only SPDX identifier as
same as other recently ASoC DAI drivers.

Signed-off-by: Katsuhiro Suzuki <suzuki.katsuhiro@socionext.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

ASoC: uniphier: add syscon property for UniPhier sound system

This patch adds syscon property for specifying soc-glue core.

Currently, soc-glue core is used for changing the state of S/PDIF
signal output pin to signal output state or Hi-Z state. After
resetting of SoC Hi-Z state is selected. This driver set to signal
output state when syscon property is available.

Signed-off-by: Katsuhiro Suzuki <suzuki.katsuhiro@socionext.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

ASoC: uniphier: add support for UniPhier AIO common driver

This patch adds common functions for UniPhier AIO audio sound
system. This provides commonly used APIs for input/output control
registers for UniPhier AIO.

This module provides all sound devices for I2S, S/PDIF and so on.
Since the AIO has mixed register map for those I/Os, it is hard
to split register areas for each sound devices.

Signed-off-by: Katsuhiro Suzuki <suzuki.katsuhiro@socionext.com>
Signed-off-by: Mark Brown <broonie@kernel.org>