From 6d48a5684a2a05176b5dc0107e557edffb7d0673 Mon Sep 17 00:00:00 2001
From: Stefano Miccoli <stefano.miccoli@polimi.it>
Date: Sun, 4 Nov 2018 22:09:21 +0100
Subject: [PATCH] clamp 'set_normalized_volume' to valid values also for ALSA
softvol
ensure that valid mixer values are set also when the ALSA driver
does not report a valid dB range ('set_raw' fallback)
correct a bug in which volume is assumed to lie in [0..100]
instead of [0..1]
---
src/mixer/plugins/volume_mapping.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/src/mixer/plugins/volume_mapping.c b/src/mixer/plugins/volume_mapping.c
index 2078d346d..61a7138af 100644
--- a/src/mixer/plugins/volume_mapping.c
+++ b/src/mixer/plugins/volume_mapping.c
@@ -135,6 +135,13 @@ static int set_normalized_volume(snd_mixer_elem_t *elem,
if (err < 0)
return err;
+ /* two special cases to avoid rounding errors at 0% and
+ 100% */
+ if (volume <= 0)
+ return set_raw[ctl_dir](elem, min);
+ else if (volume >= 1)
+ return set_raw[ctl_dir](elem, max);
+
value = lrint_dir(volume * (max - min), dir) + min;
return set_raw[ctl_dir](elem, value);
}
@@ -143,7 +150,7 @@ static int set_normalized_volume(snd_mixer_elem_t *elem,
100% */
if (volume <= 0)
return set_dB[ctl_dir](elem, min, dir);
- else if (volume >= 100)
+ else if (volume >= 1)
return set_dB[ctl_dir](elem, max, dir);
if (use_linear_dB_scale(min, max)) {