[PATCH v1] ASoC: ops: Fix integer detection for when max possible values > 1

From: Stefan Binding
Date: Fri Jun 17 2022 - 11:36:37 EST


The standard snd_soc_info_volsw() allows a two value control to be
defined as an integer control only if the control name ends in
"Volume". It achieves this by creating a substring if it contains
" Volume", and ensuring this exists at the end of the name. The
volume substring is then used to decide whether the type is a
SNDRV_CTL_ELEM_TYPE_INTEGER or SNDRV_CTL_ELEM_TYPE_BOOLEAN.
However this volume substring is only computed for a two value
control.
This means for controls where there are more than two possible
values, the substring is never created, so in this case the
substring remains NULL, and the condition yields
SNDRV_CTL_ELEM_TYPE_BOOLEAN, even though there are more than 2
possible values.
If there are more than 2 possible values for the control,
then it should always be an integer control.

Fixes: aa2a4b897132 ("ASoC: ops: Fix boolean/integer detection for simple controls")

Signed-off-by: Stefan Binding <sbinding@xxxxxxxxxxxxxxxxxxxxx>
---
sound/soc/soc-ops.c | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/sound/soc/soc-ops.c b/sound/soc/soc-ops.c
index 0267e39de2a8..1970bda074d8 100644
--- a/sound/soc/soc-ops.c
+++ b/sound/soc/soc-ops.c
@@ -183,17 +183,16 @@ int snd_soc_info_volsw(struct snd_kcontrol *kcontrol,
if (mc->platform_max && mc->platform_max < max)
max = mc->platform_max;

- /* Even two value controls ending in Volume should always be integer */
if (max == 1) {
+ /* Even two value controls ending in Volume should always be integer */
vol_string = strstr(kcontrol->id.name, " Volume");
- if (vol_string && strcmp(vol_string, " Volume"))
- vol_string = NULL;
- }
-
- if (!vol_string)
- uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
- else
+ if (vol_string && !strcmp(vol_string, " Volume"))
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+ else
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
+ } else {
uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+ }

uinfo->count = snd_soc_volsw_is_stereo(mc) ? 2 : 1;
uinfo->value.integer.min = 0;
--
2.25.1