ASoC: CS4270: export de-emphasis filter as ALSA control

The CS4270 codec features an de-emphasis filter for compensation of
audio material filtered by an 50/15 uS algorithm. Not sure whether we
should always enable it for 44100Hz sampling frequency, but it should at
least be configurable by the user.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/sound/soc/codecs/cs4270.c b/sound/soc/codecs/cs4270.c
index 59bb16d033d6..565842dcfc65 100644
--- a/sound/soc/codecs/cs4270.c
+++ b/sound/soc/codecs/cs4270.c
@@ -520,6 +520,7 @@ static const struct snd_kcontrol_new cs4270_snd_controls[] = {
         SOC_SINGLE("Digital Sidetone Switch", CS4270_FORMAT, 5, 1, 0),
         SOC_SINGLE("Soft Ramp Switch", CS4270_TRANS, 6, 1, 0),
         SOC_SINGLE("Zero Cross Switch", CS4270_TRANS, 5, 1, 0),
+        SOC_SINGLE("De-emphasis filter", CS4270_TRANS, 0, 1, 0),
         SOC_SINGLE("Popguard Switch", CS4270_MODE, 0, 1, 1),
         SOC_SINGLE("Auto-Mute Switch", CS4270_MUTE, 5, 1, 0),
         SOC_DOUBLE("Master Capture Switch", CS4270_MUTE, 3, 4, 1, 1),