diff options
Diffstat (limited to 'sound/core/control.c')
| -rw-r--r-- | sound/core/control.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/sound/core/control.c b/sound/core/control.c index 82aa1af1d1d8..8386b53acdcd 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -730,12 +730,20 @@ EXPORT_SYMBOL_GPL(snd_ctl_activate_id); * Finds the control with the old id from the card, and replaces the * id with the new one. * + * The function tries to keep the already assigned numid while replacing + * the rest. + * + * Note that this function should be used only in the card initialization + * phase. Calling after the card instantiation may cause issues with + * user-space expecting persistent numids. + * * Return: Zero if successful, or a negative error code on failure. */ int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id, struct snd_ctl_elem_id *dst_id) { struct snd_kcontrol *kctl; + int saved_numid; down_write(&card->controls_rwsem); kctl = snd_ctl_find_id(card, src_id); @@ -743,10 +751,10 @@ int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id, up_write(&card->controls_rwsem); return -ENOENT; } + saved_numid = kctl->id.numid; remove_hash_entries(card, kctl); kctl->id = *dst_id; - kctl->id.numid = card->last_numid + 1; - card->last_numid += kctl->count; + kctl->id.numid = saved_numid; add_hash_entries(card, kctl); up_write(&card->controls_rwsem); return 0; |