[alsa-devel] [PATCH] [SOUND] Fixes recording gain control

Viral Mehta viral.mehta at einfochips.com
Tue Mar 10 14:01:56 CET 2009

Have tested two usb audio mic devices.
At the time of initialization, SNDRV_MIXER_OSS_PRESENT_PVOLUME bit is not
set for MIC (slot 7).
So, the same should not be checked when an application tries to do gain 
for audio recording devices. Just check
slot->present for SNDRV_MIXER_OSS_PRESENT_CVOLUME independently.
Verified with a simple application which opens /dev/dsp for recording and
/dev/mixer for volume control.

Signed-off-by: Viral Mehta <viral.mehta at einfochips.com>
 sound/core/oss/mixer_oss.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/sound/core/oss/mixer_oss.c b/sound/core/oss/mixer_oss.c
index 4690b8b..919c7eb 100644
--- a/sound/core/oss/mixer_oss.c
+++ b/sound/core/oss/mixer_oss.c
@@ -690,7 +690,7 @@ static int snd_mixer_oss_put_volume1(struct 
snd_mixer_oss_file *fmixer,

        if (slot->present & SNDRV_MIXER_OSS_PRESENT_PVOLUME) {
                snd_mixer_oss_put_volume1_vol(fmixer, pslot, 
slot->numid[SNDRV_MIXER_OSS_ITEM_PVOLUME], left, right);
-               if (slot->present & SNDRV_MIXER_OSS_PRESENT_CVOLUME)
+       } else if (slot->present & SNDRV_MIXER_OSS_PRESENT_CVOLUME) {
                        snd_mixer_oss_put_volume1_vol(fmixer, pslot, 
slot->numid[SNDRV_MIXER_OSS_ITEM_CVOLUME], left, right);
        } else if (slot->present & SNDRV_MIXER_OSS_PRESENT_GVOLUME) {
                snd_mixer_oss_put_volume1_vol(fmixer, pslot, 
slot->numid[SNDRV_MIXER_OSS_ITEM_GVOLUME], left, right);

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