From: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Date: Wed, 19 May 2010 06:19:26 +0000 (+0200)
Subject: control: tlv: Check dB range only within the control's volume range
X-Git-Tag: v1.0.24~41
X-Git-Url: https://git.alsa-project.org/?a=commitdiff_plain;h=30ad5ed04017f7e77b25cf40f18c26396903cd23;p=alsa-lib.git

control: tlv: Check dB range only within the control's volume range

The DB_RANGE need to be used on some HW, since the gain on
volume control is not continuous, and has to be divided into
several sub DB_SCALE ranges.
ASoC has a feature to override the HW default volume range,
and in this case when the volume range is less than the
HW maximum we do not need to go through the whole DB_RANGE,
but we need to stop where the kcontrol's maximum tell us.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
---

diff --git a/src/control/tlv.c b/src/control/tlv.c
index cfd9b973..0ff052ee 100644
--- a/src/control/tlv.c
+++ b/src/control/tlv.c
@@ -140,10 +140,13 @@ int snd_tlv_get_dB_range(unsigned int *tlv, long rangemin, long rangemax,
 		pos = 2;
 		while (pos + 4 <= len) {
 			long rmin, rmax;
-			rangemin = (int)tlv[pos];
-			rangemax = (int)tlv[pos + 1];
+			long submin, submax;
+			submin = (int)tlv[pos];
+			submax = (int)tlv[pos + 1];
+			if (rangemax < submax)
+				submax = rangemax;
 			err = snd_tlv_get_dB_range(tlv + pos + 2,
-						   rangemin, rangemax,
+						   submin, submax,
 						   &rmin, &rmax);
 			if (err < 0)
 				return err;
@@ -156,6 +159,8 @@ int snd_tlv_get_dB_range(unsigned int *tlv, long rangemin, long rangemax,
 				*min = rmin;
 				*max = rmax;
 			}
+			if (rangemax == submax)
+				return 0;
 			pos += int_index(tlv[pos + 3]) + 4;
 		}
 		return 0;