[ALSA] Control API - TLV implementation for additional information like dB scale

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>

1 files changed, 4 insertions, 0 deletions

diff --git a/sound/pci/ca0106/ca0106_mixer.c b/sound/pci/ca0106/ca0106_mixer.c
index 146eed70dce6..35309b3ed8c0 100644
--- a/sound/pci/ca0106/ca0106_mixer.c
+++ b/sound/pci/ca0106/ca0106_mixer.c
@@ -70,9 +70,12 @@
 #include <sound/pcm.h>
 #include <sound/ac97_codec.h>
 #include <sound/info.h>
+#include <sound/tlv.h>
 
 #include "ca0106.h"
 
+static DECLARE_TLV_DB_SCALE(snd_ca0106_db_scale, -5150, 75, 1);
+
 static int snd_ca0106_shared_spdif_info(struct snd_kcontrol *kcontrol,
                                         struct snd_ctl_elem_info *uinfo)
 {
@@ -472,6 +475,7 @@ static int snd_ca0106_i2c_volume_put(struct snd_kcontrol *kcontrol,
         .info =  snd_ca0106_volume_info,                        \
         .get =   snd_ca0106_volume_get,                         \
         .put =   snd_ca0106_volume_put,                         \
+        .tlv =   snd_ca0106_db_scale,                           \
         .private_value = ((chid) << 8) | (reg)                  \
 }