This is in fact more symmetrical to snd_ctl_remove() than snd_ctl_add() is - the former could be named snd_ctl_remove_locked() just as well.
This will be used to dynamically change the available controls from another control's put() callback, which is already locked.
One might want to add snd_ctl_replace_locked() for completeness, but I have no use for it now.
Signed-off-by: Oswald Buddenhagen oswald.buddenhagen@gmx.de --- include/sound/control.h | 1 + sound/core/control.c | 31 +++++++++++++++++++++++++++++++ 2 files changed, 32 insertions(+)
diff --git a/include/sound/control.h b/include/sound/control.h index cc3dcc6cfb0f..d4e210831a38 100644 --- a/include/sound/control.h +++ b/include/sound/control.h @@ -134,6 +134,7 @@ void snd_ctl_notify_one(struct snd_card * card, unsigned int mask, struct snd_kc struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new * kcontrolnew, void * private_data); void snd_ctl_free_one(struct snd_kcontrol * kcontrol); int snd_ctl_add(struct snd_card * card, struct snd_kcontrol * kcontrol); +int snd_ctl_add_locked(struct snd_card * card, struct snd_kcontrol * kcontrol); int snd_ctl_remove(struct snd_card * card, struct snd_kcontrol * kcontrol); int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol, bool add_on_replace); int snd_ctl_remove_id(struct snd_card * card, struct snd_ctl_elem_id *id); diff --git a/sound/core/control.c b/sound/core/control.c index 82aa1af1d1d8..ede5ab911add 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -527,6 +527,27 @@ static int snd_ctl_add_replace(struct snd_card *card, return err; }
+static int snd_ctl_add_replace_locked(struct snd_card *card, + struct snd_kcontrol *kcontrol, + enum snd_ctl_add_mode mode) +{ + int err = -EINVAL; + + if (! kcontrol) + return err; + if (snd_BUG_ON(!card || !kcontrol->info)) + goto error; + + err = __snd_ctl_add_replace(card, kcontrol, mode); + if (err < 0) + goto error; + return 0; + + error: + snd_ctl_free_one(kcontrol); + return err; +} + /** * snd_ctl_add - add the control instance to the card * @card: the card instance @@ -547,6 +568,16 @@ int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol) } EXPORT_SYMBOL(snd_ctl_add);
+/** + * snd_ctl_add_locked - same as snd_ctl_add(), but card->controls_rwsem + * is expected to be already locked if necessary. + */ +int snd_ctl_add_locked(struct snd_card *card, struct snd_kcontrol *kcontrol) +{ + return snd_ctl_add_replace_locked(card, kcontrol, CTL_ADD_EXCLUSIVE); +} +EXPORT_SYMBOL(snd_ctl_add_locked); + /** * snd_ctl_replace - replace the control instance of the card * @card: the card instance