ALSA: Add new TLV types for dBwith min/max
Add new types for TLV dB scale specified with min/max values instead
of min/step since the resolution can't match always with the one
a device provides. For example, usb audio devices give 1/256 dB
resolution while ALSA TLV is based on 1/100 dB resolution.
The new min/max types have less problems because the possible
rounding error happens only at min/max.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/include/sound/tlv.h b/include/sound/tlv.h
index d136ea2..9fd5b19 100644
--- a/include/sound/tlv.h
+++ b/include/sound/tlv.h
@@ -35,6 +35,8 @@
#define SNDRV_CTL_TLVT_DB_SCALE 1 /* dB scale */
#define SNDRV_CTL_TLVT_DB_LINEAR 2 /* linear volume */
#define SNDRV_CTL_TLVT_DB_RANGE 3 /* dB range container */
+#define SNDRV_CTL_TLVT_DB_MINMAX 4 /* dB scale with min/max */
+#define SNDRV_CTL_TLVT_DB_MINMAX_MUTE 5 /* dB scale with min/max with mute */
#define TLV_DB_SCALE_ITEM(min, step, mute) \
SNDRV_CTL_TLVT_DB_SCALE, 2 * sizeof(unsigned int), \
@@ -42,6 +44,18 @@
#define DECLARE_TLV_DB_SCALE(name, min, step, mute) \
unsigned int name[] = { TLV_DB_SCALE_ITEM(min, step, mute) }
+/* dB scale specified with min/max values instead of step */
+#define TLV_DB_MINMAX_ITEM(min_dB, max_dB) \
+ SNDRV_CTL_TLVT_DB_MINMAX, 2 * sizeof(unsigned int), \
+ (min_dB), (max_dB)
+#define TLV_DB_MINMAX_MUTE_ITEM(min_dB, max_dB) \
+ SNDRV_CTL_TLVT_DB_MINMAX_MUTE, 2 * sizeof(unsigned int), \
+ (min_dB), (max_dB)
+#define DECLARE_TLV_DB_MINMAX(name, min_dB, max_dB) \
+ unsigned int name[] = { TLV_DB_MINMAX_ITEM(min_dB, max_dB) }
+#define DECLARE_TLV_DB_MINMAX_MUTE(name, min_dB, max_dB) \
+ unsigned int name[] = { TLV_DB_MINMAX_MUTE_ITEM(min_dB, max_dB) }
+
/* linear volume between min_dB and max_dB (.01dB unit) */
#define TLV_DB_LINEAR_ITEM(min_dB, max_dB) \
SNDRV_CTL_TLVT_DB_LINEAR, 2 * sizeof(unsigned int), \