[alsa-devel] calling snd_ctl_notify from mixer ctl_put
Hello, I want to enable/disable some mixer controls based on state of another control (switching between limiter and AGC mode). So I (re)set the SNDRV_CTL_ELEM_ACCESS_INACTIVE flag in kctl->vd[0].access and then call snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO, &kctl->id); Everyting from ctl_put() mixer callback.
When changing the control value in alsamixer, it crashes with: alsamixer: simple.c:948: snd_mixer_selem_get_enum_item: Assertion `(elem)->type == SND_MIXER_ELEM_SIMPLE' failed.
When the snd_ctl_notify() call is commented-out, it does not crash.
There is snd_ctl_activate_id() function in sound/core/control.c (not used by any driver, btw.) which does the same, protected by card->controls_rwsem. However, it locks up on that semaphore when called from the mixer callback.
Oxygen/Xonar WM8776 driver is doing the same thing - I wonder if I'm doing something wrong or if that driver crashes alsamixer too?
Is there any way to do this properly?
Ondrej Zary wrote:
I want to enable/disable some mixer controls based on state of another control (switching between limiter and AGC mode). So I (re)set the SNDRV_CTL_ELEM_ACCESS_INACTIVE flag in kctl->vd[0].access and then call snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO, &kctl->id); Everyting from ctl_put() mixer callback.
When changing the control value in alsamixer, it crashes with: alsamixer: simple.c:948: snd_mixer_selem_get_enum_item: Assertion `(elem)->type == SND_MIXER_ELEM_SIMPLE' failed.
Looks like a bug in alsamixer.
Regards, Clemens
On Friday 12 October 2012 08:03:13 Clemens Ladisch wrote:
Ondrej Zary wrote:
I want to enable/disable some mixer controls based on state of another control (switching between limiter and AGC mode). So I (re)set the SNDRV_CTL_ELEM_ACCESS_INACTIVE flag in kctl->vd[0].access and then call snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO, &kctl->id); Everyting from ctl_put() mixer callback.
When changing the control value in alsamixer, it crashes with: alsamixer: simple.c:948: snd_mixer_selem_get_enum_item: Assertion `(elem)->type == SND_MIXER_ELEM_SIMPLE' failed.
Looks like a bug in alsamixer.
Thanks. I've now tried some other mixers that are present in Debian and most of them are unusable: alsamixergui: does not understand ENUM controls gnome-alsamixer: does not understand ENUM controls gnome-volume-control: crashes like alsamixer xfce4-mixer: crashes like alsamixer kmix (TDE 3.5.13): does not update controls when switching limiter/AGC kmix (KDE 4): crashes like alsamixer (other mixers won't even run as they seem to be OSS-only)
But there's one that works fine: QasMixer.
2012-10-14 上午5:24 於 "Ondrej Zary" linux@rainbow-software.org 寫道：
On Friday 12 October 2012 08:03:13 Clemens Ladisch wrote:
Ondrej Zary wrote:
I want to enable/disable some mixer controls based on state of another control (switching between limiter and AGC mode). So I (re)set the SNDRV_CTL_ELEM_ACCESS_INACTIVE flag in kctl->vd[0].access and then call snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_INFO,
&kctl->id);
Everyting from ctl_put() mixer callback.
When changing the control value in alsamixer, it crashes with: alsamixer: simple.c:948: snd_mixer_selem_get_enum_item: Assertion `(elem)->type == SND_MIXER_ELEM_SIMPLE' failed.
Looks like a bug in alsamixer.
Thanks. I've now tried some other mixers that are present in Debian and
most
of them are unusable: alsamixergui: does not understand ENUM controls gnome-alsamixer: does not understand ENUM controls gnome-volume-control: crashes like alsamixer xfce4-mixer: crashes like alsamixer kmix (TDE 3.5.13): does not update controls when switching limiter/AGC kmix (KDE 4): crashes like alsamixer (other mixers won't even run as they seem to be OSS-only)
But there's one that works fine: QasMixer.
the alsamixer also crash only when "independent headphone" enum of ad1988 is visible in alsamixer when the analog or headphone playback stream close/open in ubuntu 12.4
participants (3)
-
Clemens Ladisch -
Ondrej Zary -
Raymond Yau