| Message ID | 20230606094035.14808-1-tiwai@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ALSA: control: Keep the previous numid at snd_ctl_rename_id() | expand |
On 06. 06. 23 11:40, Takashi Iwai wrote: > We don't need to change the numid at each time snd_ctl_rename_id() is > called, as the control element size itself doesn't change. Let's keep > the previous numid value. I would also highlight in the comment that snd_ctl_rename_id() should be used only in the card initialization phase. It may cause issues with the user space (persistent numid) for the dynamic controls. Reviewed-by: Jaroslav Kysela <perex@perex.cz>
On Tue, 06 Jun 2023 13:15:20 +0200, Jaroslav Kysela wrote: > > On 06. 06. 23 11:40, Takashi Iwai wrote: > > We don't need to change the numid at each time snd_ctl_rename_id() is > > called, as the control element size itself doesn't change. Let's keep > > the previous numid value. > > I would also highlight in the comment that snd_ctl_rename_id() should > be used only in the card initialization phase. It may cause issues > with the user space (persistent numid) for the dynamic controls. Sounds good. I'll add the note in the commit. > Reviewed-by: Jaroslav Kysela <perex@perex.cz> Thanks! Takashi
diff --git a/sound/core/control.c b/sound/core/control.c index 82aa1af1d1d8..f4a90a687ae5 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -730,12 +730,16 @@ 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. + * * 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 +747,10 @@ 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;
We don't need to change the numid at each time snd_ctl_rename_id() is called, as the control element size itself doesn't change. Let's keep the previous numid value. Signed-off-by: Takashi Iwai <tiwai@suse.de> --- sound/core/control.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)